Jump to content

MediaWiki:Gadget-PreloadEditor.js

From The Petit Planet Wiki
Revision as of 09:21, 21 September 2026 by ReisuDesign (talk | contribs)

Note: After publishing, you may have to bypass your browser's cache to see the changes.

  • Firefox / Safari: Hold Shift while clicking Reload, or press either Ctrl-F5 or Ctrl-R (⌘-R on a Mac)
  • Google Chrome: Press Ctrl-Shift-R (⌘-Shift-R on a Mac)
  • Edge: Hold Ctrl while clicking Refresh, or press Ctrl-F5.
(function (mw, $) {
    'use strict';

    const PreloadEditor = {
        version: '0.4.0',

        state: {
            preloadTitle: '',
            preloadSource: '',
            preloadContent: '',
            config: null,
            variables: [],
            conditions: [],
            selectedVariable: 'PAGE',
            mode: 'idle',
            dirty: false
        },

        editor: null,
        editorView: null,
        analysis: null,
        root: null,
        workspace: null,
        status: null,
        editorTools: null,

        defaults: {
            preload:
                '<includeonly>\n<!-- preload here -->\n</includeonly>\n<noinclude>{{Documentation|type=Preload|content={{Preload Template}}}}</noinclude>\n'
        },

        // API

        async getPage(title) {
            const response = await new mw.Api().get({
                action: 'query',
                prop: 'revisions',
                titles: title,
                rvprop: 'content',
                rvslots: 'main',
                formatversion: 2
            });

            const page =
                response &&
                response.query &&
                response.query.pages &&
                response.query.pages[0];

            if (!page || page.missing) return null;

            const content =
                page.revisions &&
                page.revisions[0] &&
                page.revisions[0].slots &&
                page.revisions[0].slots.main &&
                page.revisions[0].slots.main.content;

            return {
                title: page.title || title,
                content: typeof content === 'string' ? content : ''
            };
        },

        async pageExists(title) {
            return !!await this.getPage(title);
        },

        async searchPages(query) {
            const response = await new mw.Api().get({
                action: 'query',
                list: 'search',
                srsearch: query,
                srlimit: 10,
                srnamespace: 10,
                formatversion: 2
            });

            return (
                response &&
                response.query &&
                response.query.search
            ) || [];
        },

        async savePage(title, content, summary, createOnly) {
            const params = {
                action: 'edit',
                title,
                text: content,
                summary: summary || 'Updated with Preload Editor',
                formatversion: 2
            };

            if (createOnly) params.createonly = true;

            return new mw.Api().postWithToken('csrf', params);
        },

        // Preload parsing

        extractIncludeonly(source) {
            const match = String(source || '').match(
                /<includeonly>([\s\S]*?)<\/includeonly>/i
            );

            return match
                ? match[1].trim()
                : String(source || '').trim();
        },

        findVariables(content) {
            const variables = [];
            const pattern = /%%([A-Za-z0-9_-]+)%%/g;
            let match;

            while ((match = pattern.exec(content)) !== null) {
                const name = match[1].toUpperCase();

                if (!variables.includes(name)) {
                    variables.push(name);
                }
            }

            return variables;
        },

        findConditions(content) {
            const conditions = [];
            const pattern =
                /<!--\s*@(if|elseif|else|endif)\b([\s\S]*?)-->/gi;

            let match;

            while ((match = pattern.exec(content)) !== null) {
                conditions.push({
                    type: match[1].toLowerCase(),
                    expression: match[2].trim(),
                    index: match.index
                });
            }

            return conditions;
        },

        findConditionVariables(content) {
            const variables = [];

            this.findConditions(content).forEach(condition => {
                if (
                    condition.type !== 'if' &&
                    condition.type !== 'elseif'
                ) {
                    return;
                }

                const matches =
                    condition.expression.match(
                        /[A-Za-z0-9_-]+/g
                    ) || [];

                matches.forEach(name => {
                    name = name.toUpperCase();

                    if (!variables.includes(name)) {
                        variables.push(name);
                    }
                });
            });

            return variables;
        },

        analyzePreload(content) {
            return {
                variables: this.findVariables(content),
                conditions: this.findConditions(content),
                conditionVariables:
                    this.findConditionVariables(content)
            };
        },

        // Config

        getAutomaticPageField() {
            return {
                label: 'Page Name',
                description: 'Name of the page.',
                type: 'page',
                required: true,
                namespace: 'Main',
                'allow-new': true
            };
        },

        emptyConfig() {
            return {
                settings: {
                    incomplete: 'add-stub'
                },
                fields: {
                    PAGE: this.getAutomaticPageField()
                }
            };
        },

        normalizeConfig(config) {
            if (
                !config ||
                typeof config !== 'object' ||
                Array.isArray(config)
            ) {
                config = this.emptyConfig();
            }

            if (
                !config.settings ||
                typeof config.settings !== 'object' ||
                Array.isArray(config.settings)
            ) {
                config.settings = {};
            }

            if (
                !config.fields ||
                typeof config.fields !== 'object' ||
                Array.isArray(config.fields)
            ) {
                config.fields = {};
            }

            // PAGE is always a special, automatic field.
            // Its configuration is precompiled and only displayed
            // in the editor for reference.
            config.fields.PAGE =
                this.getAutomaticPageField();

            return config;
        },

        createDefaultField(name, analysis) {
            return {
                label: this.humanizeName(name),
                description: '',
                type:
                    analysis.conditionVariables.includes(name)
                        ? 'boolean'
                        : 'text'
            };
        },

        humanizeName(name) {
            return String(name || '')
                .replace(/[_-]+/g, ' ')
                .replace(/([a-z])([A-Z])/g, '$1 $2')
                .replace(/\s+/g, ' ')
                .trim()
                .replace(
                    /\b\w/g,
                    char => char.toUpperCase()
                );
        },

        prepareConfigForVariables(config, analysis) {
            config = this.normalizeConfig(config);

            const existing = config.fields || {};
            const fields = {};

            // PAGE is always automatic/precompiled.
            fields.PAGE = this.getAutomaticPageField();

            analysis.variables.forEach(name => {
                if (name === 'PAGE') return;

                fields[name] =
                    existing[name] ||
                    this.createDefaultField(
                        name,
                        analysis
                    );
            });

            Object.keys(existing).forEach(name => {
                const upper = name.toUpperCase();

                if (
                    upper !== 'PAGE' &&
                    !fields[upper]
                ) {
                    fields[upper] = existing[name];
                }
            });

            config.fields = fields;

            return config;
        },

        validateConfig(config, analysis) {
            const errors = [];
            const warnings = [];

            if (
                !config ||
                typeof config !== 'object' ||
                Array.isArray(config)
            ) {
                return {
                    valid: false,
                    errors: ['Config must be an object.'],
                    warnings: []
                };
            }

            if (
                !config.fields ||
                typeof config.fields !== 'object' ||
                Array.isArray(config.fields)
            ) {
                return {
                    valid: false,
                    errors: ['"fields" must be an object.'],
                    warnings
                };
            }

            const configured =
                Object.keys(config.fields).map(
                    name => name.toUpperCase()
                );

            analysis.variables.forEach(name => {
                if (!configured.includes(name)) {
                    errors.push(
                        'Variable "' +
                        name +
                        '" is not configured.'
                    );
                }
            });

            configured.forEach(name => {
                if (!analysis.variables.includes(name)) {
                    warnings.push(
                        'Field "' +
                        name +
                        '" is not used by the preload.'
                    );
                }
            });

            if (!configured.includes('PAGE')) {
                errors.push(
                    'PAGE must always be configured.'
                );
            }

            Object.entries(config.fields).forEach(
                ([name, field]) => {
                    if (
                        !field ||
                        typeof field !== 'object' ||
                        Array.isArray(field)
                    ) {
                        errors.push(
                            'Field "' +
                            name +
                            '" must be an object.'
                        );
                        return;
                    }

                    if (!field.type) {
                        warnings.push(
                            'Field "' +
                            name +
                            '" has no type.'
                        );
                    }

                    if (
                        (
                            field.type === 'select' ||
                            field.type === 'multiselect'
                        ) &&
                        !field.source &&
                        !Array.isArray(field.options)
                    ) {
                        warnings.push(
                            'Field "' +
                            name +
                            '" is a ' +
                            field.type +
                            ' without a source or manual options.'
                        );
                    }
                }
            );

            return {
                valid: !errors.length,
                errors,
                warnings
            };
        },

        // Transformation helpers

        transformationObject(
            transform,
            prefix,
            suffix,
            from,
            to
        ) {
            if (!transform) return null;

            switch (transform) {
                case 'remove-prefix':
                    return prefix
                        ? { transform, prefix }
                        : null;

                case 'remove-suffix':
                    return suffix
                        ? { transform, suffix }
                        : null;

                case 'replace':
                    return from === ''
                        ? null
                        : {
                            transform,
                            from,
                            to: to || ''
                        };

                default:
                    return null;
            }
        },

        // UI helpers

        createSection(title, className) {
            const section = $('<section>')
                .addClass('preload-editor-section');

            if (className) {
                section.addClass(className);
            }

            $('<h2>')
                .addClass(
                    'preload-editor-section-title'
                )
                .text(title)
                .appendTo(section);

            return section;
        },

        createButton(label, className, callback) {
            const button = $('<button>')
                .attr('type', 'button')
                .addClass('preload-editor-button')
                .text(label);

            if (className) {
                button.addClass(className);
            }

            if (callback) {
                button.on(
                    'click.preloadEditor',
                    callback
                );
            }

            return button;
        },

        fieldRow(label, input, description) {
            const row = $('<div>')
                .addClass('preload-editor-field');

            $('<label>')
                .addClass('preload-editor-label')
                .text(label)
                .appendTo(row);

            if (description) {
                $('<div>')
                    .addClass('preload-editor-help')
                    .text(description)
                    .appendTo(row);
            }

            row.append(input);

            return row;
        },

        textInput(value, placeholder) {
            return $('<input>')
                .attr({
                    type: 'text',
                    value:
                        value == null
                            ? ''
                            : value,
                    placeholder:
                        placeholder || ''
                })
                .addClass('preload-editor-input');
        },

        textarea(value) {
            return $('<textarea>')
                .val(
                    value == null
                        ? ''
                        : value
                )
                .addClass(
                    'preload-editor-textarea'
                );
        },

        checkbox(checked) {
            return $('<input>')
                .attr('type', 'checkbox')
                .prop('checked', !!checked)
                .addClass(
                    'preload-editor-checkbox'
                );
        },

        select(options, value) {
            const select = $('<select>')
                .addClass(
                    'preload-editor-select'
                );

            options.forEach(option => {
                $('<option>')
                    .attr(
                        'value',
                        option.value
                    )
                    .text(option.label)
                    .prop(
                        'selected',
                        String(option.value) ===
                        String(
                            value === undefined
                                ? ''
                                : value
                        )
                    )
                    .appendTo(select);
            });

            return select;
        },

        // CodeMirror

        destroyEditor() {
            if (!this.editor) {
                this.editorView = null;
                this.editorTools = null;
                return;
            }

            const {
                view,
                inputHandler
            } = this.editor;

            if (view && inputHandler) {
                view.dom.removeEventListener(
                    'input',
                    inputHandler
                );
            }

            if (view) {
                view.destroy();
            }

            this.editor = null;
            this.editorView = null;
            this.editorTools = null;
        },

        getEditorView() {
            return this.editorView;
        },

        getEditorContent() {
            if (
                this.editorView &&
                this.editorView.state
            ) {
                return this.editorView.state.doc.toString();
            }

            return this.state.preloadContent || '';
        },

        setEditorContent(content) {
            content = String(content || '');

            if (!this.editorView) {
                this.state.preloadContent = content;
                return;
            }

            const current =
                this.editorView.state.doc.toString();

            if (current === content) return;

            this.editorView.dispatch({
                changes: {
                    from: 0,
                    to: this.editorView.state.doc.length,
                    insert: content
                }
            });
        },

        getEditorSelection() {
            if (
                !this.editorView ||
                !this.editorView.state
            ) {
                return null;
            }

            const selection =
                this.editorView.state.selection.main;

            return {
                from: selection.from,
                to: selection.to,
                text:
                    this.editorView.state.doc.sliceString(
                        selection.from,
                        selection.to
                    )
            };
        },

        focusEditor() {
            if (this.editorView) {
                this.editorView.focus();
            }
        },

        insertEditorText(
            text,
            selectionFrom,
            selectionTo,
            cursorPosition
        ) {
            if (!this.editorView) return;

            const view = this.editorView;
            const selection =
                view.state.selection.main;

            const from =
                selectionFrom === undefined
                    ? selection.from
                    : selectionFrom;

            const to =
                selectionTo === undefined
                    ? selection.to
                    : selectionTo;

            const cursor =
                cursorPosition === undefined
                    ? from + text.length
                    : cursorPosition;

            view.dispatch({
                changes: {
                    from,
                    to,
                    insert: text
                },
                selection: {
                    anchor: cursor
                }
            });

            view.focus();
        },

        // V2.3 editor tools

        wrapSelectionWithVariable() {
            const selected =
                this.getEditorSelection();

            if (
                !selected ||
                selected.from === selected.to
            ) {
                this.focusEditor();
                return;
            }

            const replacement =
                '%%' +
                selected.text +
                '%%';

            this.insertEditorText(
                replacement,
                selected.from,
                selected.to,
                selected.from +
                    replacement.length
            );
        },

        insertVariable(name) {
            name = String(name || '')
                .trim()
                .toUpperCase();

            if (!name) return;

            const selected =
                this.getEditorSelection();

            if (!selected) return;

            const text =
                '%%' +
                name +
                '%%';

            this.insertEditorText(
                text,
                selected.from,
                selected.to
            );
        },

        insertCondition(type, variable) {
            type =
                String(type || '')
                    .toLowerCase();

            variable =
                String(variable || '')
                    .trim()
                    .toUpperCase();

            const selected =
                this.getEditorSelection();

            if (!selected) return;

            let text;
            let cursorOffset;

            switch (type) {
                case 'if': {
                    if (!variable) return;

                    const opening =
                        '<!-- @if ' +
                        variable +
                        ' -->';

                    const closing =
                        '<!-- @endif -->';

                    if (
                        selected.from !==
                        selected.to
                    ) {
                        text =
                            opening +
                            '\n' +
                            selected.text +
                            '\n' +
                            closing;

                        cursorOffset =
                            text.length;
                    } else {
                        text =
                            opening +
                            '\n\n' +
                            closing;

                        cursorOffset =
                            opening.length + 1;
                    }

                    break;
                }

                case 'elseif':
                    text = '<!-- @elseif -->';
                    cursorOffset = text.length;
                    break;

                case 'else':
                    text = '<!-- @else -->';
                    cursorOffset = text.length;
                    break;

                case 'endif':
                    text = '<!-- @endif -->';
                    cursorOffset = text.length;
                    break;

                default:
                    return;
            }

            this.insertEditorText(
                text,
                selected.from,
                selected.to,
                selected.from +
                    cursorOffset
            );
        },

        getToolVariables() {
            const variables =
                new Set(['PAGE']);

            if (
                this.analysis &&
                this.analysis.variables
            ) {
                this.analysis.variables.forEach(
                    name => {
                        variables.add(
                            String(name).toUpperCase()
                        );
                    }
                );
            }

            return Array.from(variables);
        },

        createToolSelect(options, className) {
            const select = $('<select>')
                .addClass(
                    'preload-editor-tool-select'
                );

            if (className) {
                select.addClass(className);
            }

            options.forEach(option => {
                $('<option>')
                    .attr(
                        'value',
                        option.value
                    )
                    .text(option.label)
                    .appendTo(select);
            });

            return select;
        },

        updateEditorToolVariables() {
            if (!this.editorTools) return;

            const variables =
                this.getToolVariables();

            const current =
                this.editorTools.variableSelect.val();

            const currentCondition =
                this.editorTools
                    .conditionVariableSelect
                    .val();

            const populate = (
                select,
                value
            ) => {
                select.empty();

                variables.forEach(name => {
                    $('<option>')
                        .attr(
                            'value',
                            name
                        )
                        .text(name)
                        .appendTo(select);
                });

                if (
                    value &&
                    variables.includes(value)
                ) {
                    select.val(value);
                } else if (variables.length) {
                    select.val(
                        variables[0]
                    );
                }
            };

            populate(
                this.editorTools.variableSelect,
                current
            );

            populate(
                this.editorTools
                    .conditionVariableSelect,
                currentCondition
            );
        },

        updateConditionVariableVisibility() {
            if (!this.editorTools) return;

            const type =
                this.editorTools
                    .conditionTypeSelect
                    .val();

            this.editorTools
                .conditionVariableWrap
                .toggle(type === 'if');
        },

        renderEditorTools() {
            const tools = $('<div>')
                .addClass(
                    'preload-editor-tools'
                );

            const wrapGroup = $('<div>')
                .addClass(
                    'preload-editor-tool-group ' +
                    'preload-editor-tool-group-wrap'
                );

            wrapGroup.append(
                this.createButton(
                    'Wrap selection with %%',
                    'preload-editor-tool-button',
                    () =>
                        this.wrapSelectionWithVariable()
                )
            );

            const variableGroup = $('<div>')
                .addClass(
                    'preload-editor-tool-group ' +
                    'preload-editor-tool-group-variable'
                );

            $('<span>')
                .addClass(
                    'preload-editor-tool-label'
                )
                .text(
                    'Insert existing variable'
                )
                .appendTo(variableGroup);

            const variableSelect =
                this.createToolSelect(
                    [],
                    'preload-editor-variable-select'
                );

            variableGroup.append(
                variableSelect,
                this.createButton(
                    'Insert',
                    'preload-editor-tool-button',
                    () =>
                        this.insertVariable(
                            variableSelect.val()
                        )
                )
            );

            const conditionGroup = $('<div>')
                .addClass(
                    'preload-editor-tool-group ' +
                    'preload-editor-tool-group-condition'
                );

            $('<span>')
                .addClass(
                    'preload-editor-tool-label'
                )
                .text('Insert condition')
                .appendTo(conditionGroup);

            const conditionTypeSelect =
                this.createToolSelect(
                    [
                        {
                            value: 'if',
                            label: '@if'
                        },
                        {
                            value: 'elseif',
                            label: '@elseif'
                        },
                        {
                            value: 'else',
                            label: '@else'
                        },
                        {
                            value: 'endif',
                            label: '@endif'
                        }
                    ],
                    'preload-editor-condition-type-select'
                );

            const conditionVariableSelect =
                this.createToolSelect(
                    [],
                    'preload-editor-condition-variable-select'
                );

            const conditionVariableWrap =
                $('<span>')
                    .addClass(
                        'preload-editor-condition-variable'
                    )
                    .append(
                        conditionVariableSelect
                    );

            const insertCondition =
                this.createButton(
                    'Insert',
                    'preload-editor-tool-button',
                    () =>
                        this.insertCondition(
                            conditionTypeSelect.val(),
                            conditionVariableSelect.val()
                        )
                );

            conditionTypeSelect.on(
                'change.preloadEditor',
                () =>
                    this.updateConditionVariableVisibility()
            );

            conditionGroup.append(
                conditionTypeSelect,
                conditionVariableWrap,
                insertCondition
            );

            tools.append(
                wrapGroup,
                variableGroup,
                conditionGroup
            );

            this.editorTools = {
                root: tools,
                variableSelect,
                conditionTypeSelect,
                conditionVariableSelect,
                conditionVariableWrap,
                insertCondition
            };

            this.updateEditorToolVariables();
            this.updateConditionVariableVisibility();

            return tools;
        },

        updateEditorTools() {
            this.updateEditorToolVariables();
            this.updateConditionVariableVisibility();
        },

        // Preload syntax highlighting

        getKnownVariables() {
            const known =
                new Set(['PAGE']);

            const fields =
                this.state.config &&
                this.state.config.fields;

            if (
                fields &&
                typeof fields === 'object'
            ) {
                Object.keys(fields).forEach(
                    name => {
                        known.add(
                            String(name).toUpperCase()
                        );
                    }
                );
            }

            return known;
        },

        createSyntaxDecorations(
            state,
            Decoration
        ) {
            const decorations = [];
            const source =
                state.doc.toString();

            const knownVariables =
                this.getKnownVariables();

            const variablePattern =
                /%%([A-Za-z0-9_-]+)%%/g;

            let match;

            while (
                (match =
                    variablePattern.exec(source)) !==
                null
            ) {
                const name =
                    match[1].toUpperCase();

                const known =
                    knownVariables.has(name);

                decorations.push(
                    Decoration.mark({
                        class: [
                            'preload-editor-syntax-variable',
                            known
                                ? 'preload-editor-syntax-variable-known'
                                : 'preload-editor-syntax-variable-unknown'
                        ].join(' ')
                    }).range(
                        match.index,
                        match.index +
                            match[0].length
                    )
                );
            }

            const conditionPattern =
                /<!--\s*@(if|elseif|else|endif)\b([\s\S]*?)-->/gi;

            while (
                (match =
                    conditionPattern.exec(source)) !==
                null
            ) {
                decorations.push(
                    Decoration.mark({
                        class:
                            'preload-editor-syntax-condition'
                    }).range(
                        match.index,
                        match.index +
                            match[0].length
                    )
                );

                const directiveStart =
                    match.index +
                    match[0].indexOf('@');

                decorations.push(
                    Decoration.mark({
                        class:
                            'preload-editor-syntax-directive'
                    }).range(
                        directiveStart,
                        directiveStart +
                            match[1].length +
                            1
                    )
                );

                const type =
                    match[1].toLowerCase();

                if (
                    type !== 'if' &&
                    type !== 'elseif'
                ) {
                    continue;
                }

                const expression =
                    match[2];

                const expressionStart =
                    match.index +
                    match[0].indexOf(
                        expression
                    );

                const expressionPattern =
                    /[A-Za-z0-9_-]+/g;

                let expressionMatch;

                while (
                    (
                        expressionMatch =
                            expressionPattern.exec(
                                expression
                            )
                    ) !== null
                ) {
                    const name =
                        expressionMatch[0]
                            .toUpperCase();

                    if (
                        !knownVariables.has(name)
                    ) {
                        continue;
                    }

                    const start =
                        expressionStart +
                        expressionMatch.index;

                    decorations.push(
                        Decoration.mark({
                            class:
                                'preload-editor-syntax-condition-variable'
                        }).range(
                            start,
                            start +
                                expressionMatch[0]
                                    .length
                        )
                    );
                }
            }

            return Decoration.set(
                decorations,
                true
            );
        },

        async installSyntaxHighlighting(view) {
            await mw.loader.using(
                'ext.CodeMirror.v6.lib'
            );

            const require =
                mw.loader.require;

            const {
                StateField,
                StateEffect,
                EditorView,
                Decoration
            } = require(
                'ext.CodeMirror.v6.lib'
            );

            const syntaxField =
                StateField.define({
                    create: state =>
                        this.createSyntaxDecorations(
                            state,
                            Decoration
                        ),

                    update: (
                        decorations,
                        transaction
                    ) =>
                        transaction.docChanged
                            ? this.createSyntaxDecorations(
                                transaction.state,
                                Decoration
                            )
                            : decorations,

                    provide: field =>
                        EditorView.decorations.from(
                            field
                        )
                });

            view.dispatch({
                effects:
                    StateEffect.appendConfig.of(
                        syntaxField
                    )
            });

            this.editor.syntaxField =
                syntaxField;
        },

        // CodeMirror mounting

        async mountCodeMirror(textarea) {
            return new Promise(
                (resolve, reject) => {
                    let settled = false;

                    const cleanup = () => {
                        mw.hook(
                            'dev.CCM.ready'
                        ).remove(onReady);

                        mw.hook(
                            'dev.CCM.load'
                        ).remove(onLoad);
                    };

                    const onReady = async cm => {
                        if (
                            settled ||
                            !cm ||
                            cm.textarea !==
                                textarea ||
                            !cm.view
                        ) {
                            return;
                        }

                        settled = true;
                        cleanup();

                        const view = cm.view;

                        const inputHandler =
                            () => {
                                this.state
                                    .preloadContent =
                                    view.state.doc.toString();

                                this.state.dirty =
                                    true;

                                this.reanalyze();
                                this.renderVariablesBySelector();
                                this.renderVariableConfigurationBySelector();
                                this.renderAnalysisBySelector();
                                this.renderConfigPreviewBySelector();
                                this.updateEditorTools();
                            };

                        view.dom.addEventListener(
                            'input',
                            inputHandler
                        );

                        view.dom.classList.add(
                            'preload-editor-codemirror'
                        );

                        const wrapper =
                            view.dom.closest(
                                '.ext-codemirror-wrapper'
                            );

                        if (wrapper) {
                            wrapper.classList.add(
                                'preload-editor-codemirror-wrapper'
                            );
                        }

                        this.editor = {
                            cm,
                            view,
                            textarea,
                            inputHandler
                        };

                        this.editorView = view;

                        this.state.preloadContent =
                            view.state.doc.toString();

                        try {
                            await this.installSyntaxHighlighting(
                                view
                            );

                            resolve(view);
                        } catch (error) {
                            reject(error);
                        }
                    };

                    const onLoad = loader => {
                        if (
                            settled ||
                            typeof loader !==
                                'function'
                        ) {
                            return;
                        }

                        try {
                            loader(textarea);
                        } catch (error) {
                            settled = true;
                            cleanup();
                            reject(error);
                        }
                    };

                    mw.hook(
                        'dev.CCM.ready'
                    ).add(onReady);

                    mw.hook(
                        'dev.CCM.load'
                    ).add(onLoad);
                }
            );
        },

        // Main UI

        init() {
            const root =
                $('#mw-content-text');

            if (!root.length) return;

            this.root = $('<div>')
                .attr(
                    'id',
                    'preload-editor'
                )
                .addClass(
                    'preload-editor'
                );

            root.append(this.root);

            this.renderShell();
        },

        renderShell() {
            this.destroyEditor();
            this.root.empty();

            const loader =
                this.createSection(
                    'Preload'
                );

            const titleInput =
                this.textInput(
                    this.state.preloadTitle,
                    'Template:Example/Preload'
                ).attr(
                    'id',
                    'preload-editor-title-input'
                );

            const loadButton =
                this.createButton(
                    'Load',
                    'preload-editor-button-primary',
                    () =>
                        this.loadExisting(
                            titleInput.val()
                        )
                );

            const newButton =
                this.createButton(
                    'New',
                    '',
                    () => this.startNew()
                );

            const sampleButton =
                this.createButton(
                    'Load Sample Page',
                    '',
                    () =>
                        this.loadSamplePage()
                );

            loader.append(
                $('<div>')
                    .addClass(
                        'preload-editor-toolbar'
                    )
                    .append(
                        titleInput,
                        loadButton,
                        newButton,
                        sampleButton
                    )
            );

            this.root.append(loader);

            this.status =
                $('<div>')
                    .addClass(
                        'preload-editor-status'
                    );

            this.root.append(
                this.status
            );

            this.workspace =
                $('<div>')
                    .addClass(
                        'preload-editor-workspace'
                    );

            this.root.append(
                this.workspace
            );

            this.renderWelcome();
        },

        renderWelcome() {
            this.workspace.empty();

            const section =
                this.createSection(
                    'Get started'
                );

            $('<p>')
                .text(
                    'Load an existing preload, create a new one, or start from a sample wiki page.'
                )
                .appendTo(section);

            const tips =
                $('<ul>')
                    .addClass(
                        'preload-editor-tips'
                    );

            [
                'Existing preload: loads the preload and its config.json if available.',
                'New preload: starts with the standard Preload Template structure.',
                'Sample page: loads normal wiki page content so you can turn it into a preload.'
            ].forEach(text => {
                $('<li>')
                    .text(text)
                    .appendTo(tips);
            });

            section.append(tips);
            this.workspace.append(section);
        },

        setStatus(message, type) {
            if (!this.status) return;

            this.status.removeClass(
                'is-error',
                'is-success',
                'is-warning',
                'is-loading'
            );

            if (type) {
                this.status.addClass(
                    'is-' + type
                );
            }

            this.status.text(
                message || ''
            );
        },

        // Load / create

        async loadExisting(title) {
            title =
                String(title || '').trim();

            if (!title) {
                mw.notify(
                    'Enter a preload page title first.',
                    { type: 'warn' }
                );

                return;
            }

            this.setStatus(
                'Loading preload...',
                'loading'
            );

            try {
                const page =
                    await this.getPage(title);

                if (!page) {
                    const suggestions =
                        await this.findSimilarPreloads(
                            title
                        );

                    this.renderMissingPage(
                        title,
                        suggestions
                    );

                    this.setStatus(
                        'Preload not found.',
                        'warning'
                    );

                    return;
                }

                await this.loadDefinition(
                    page.title,
                    page.content
                );

                this.setStatus(
                    'Preload loaded.',
                    'success'
                );
            } catch (error) {
                console.error(
                    'Preload Editor:',
                    error
                );

                this.setStatus(
                    error.message ||
                        'Could not load preload.',
                    'error'
                );
            }
        },

        async findSimilarPreloads(title) {
            let query =
                title
                    .replace(
                        /\/Preload$/i,
                        ''
                    )
                    .trim();

            if (!query) {
                query = title;
            }

            try {
                const results =
                    await this.searchPages(
                        query
                    );

                return results.filter(
                    result =>
                        /\/Preload$/i.test(
                            result.title
                        )
                );
            } catch (error) {
                console.error(
                    'Preload Editor search:',
                    error
                );

                return [];
            }
        },

        renderMissingPage(
            title,
            suggestions
        ) {
            this.workspace.empty();

            const section =
                this.createSection(
                    'Preload not found'
                );

            $('<p>')
                .text(
                    'No preload exists at "' +
                    title +
                    '".'
                )
                .appendTo(section);

            if (suggestions.length) {
                $('<h3>')
                    .text('Similar preloads')
                    .appendTo(section);

                const list =
                    $('<div>')
                        .addClass(
                            'preload-editor-suggestions'
                        );

                suggestions.forEach(
                    result => {
                        list.append(
                            this.createButton(
                                result.title,
                                'preload-editor-suggestion',
                                () =>
                                    this.loadExisting(
                                        result.title
                                    )
                            )
                        );
                    }
                );

                section.append(list);
            }

            section.append(
                this.createButton(
                    'Create this preload',
                    'preload-editor-button-primary',
                    () =>
                        this.startNew(title)
                )
            );

            this.workspace.append(section);
        },

        async startNew(title) {
            title =
                String(title || '').trim();

            this.state = {
                preloadTitle: title,
                preloadSource: '',
                preloadContent:
                    this.defaults.preload,
                config:
                    this.emptyConfig(),
                variables: ['PAGE'],
                conditions: [],
                selectedVariable: 'PAGE',
                mode: 'new',
                dirty: true
            };

            this.renderEditor();

            this.setStatus(
                'Creating a new preload.',
                'success'
            );
        },

        async loadSamplePage() {
            const result =
                await this.createPromptDialog(
                    'Load Sample Page',
                    'Enter the title of a normal wiki page to use as the starting point.'
                );

            if (!result) return;

            this.setStatus(
                'Loading sample page...',
                'loading'
            );

            try {
                const page =
                    await this.getPage(result);

                if (!page) {
                    throw new Error(
                        'Sample page not found: ' +
                        result
                    );
                }

                const sample =
                    this.convertSampleToPreload(
                        page.content
                    );

                this.state = {
                    preloadTitle: '',
                    preloadSource: '',
                    preloadContent: sample,
                    config:
                        this.emptyConfig(),
                    variables: ['PAGE'],
                    conditions: [],
                    selectedVariable: 'PAGE',
                    mode: 'new',
                    dirty: true
                };

                this.reanalyze();
                this.renderEditor();

                this.setStatus(
                    'Sample page loaded.',
                    'success'
                );
            } catch (error) {
                console.error(
                    'Preload Editor sample:',
                    error
                );

                this.setStatus(
                    error.message ||
                        'Could not load sample page.',
                    'error'
                );
            }
        },

        convertSampleToPreload(source) {
            let content =
                String(source || '').trim();

            const include =
                content.match(
                    /<includeonly>([\s\S]*?)<\/includeonly>/i
                );

            if (include) {
                content =
                    include[1].trim();
            }

            content =
                content
                    .replace(
                        /<noinclude>[\s\S]*?<\/noinclude>/gi,
                        ''
                    )
                    .trim();

            return (
                '<includeonly>\n' +
                content +
                '\n</includeonly>\n' +
                '<noinclude>{{Documentation|type=Preload|content={{Preload Template}}}}</noinclude>\n'
            );
        },

        createPromptDialog(
            title,
            message
        ) {
            return new Promise(
                resolve => {
                    const overlay =
                        $('<div>')
                            .addClass(
                                'preload-editor-prompt-overlay'
                            );

                    const box =
                        $('<div>')
                            .addClass(
                                'preload-editor-prompt'
                            );

                    $('<h2>')
                        .text(title)
                        .appendTo(box);

                    $('<p>')
                        .text(message)
                        .appendTo(box);

                    const input =
                        this.textInput();

                    const buttons =
                        $('<div>')
                            .addClass(
                                'preload-editor-prompt-buttons'
                            );

                    const cancel =
                        this.createButton(
                            'Cancel',
                            '',
                            () => {
                                overlay.remove();
                                resolve(null);
                            }
                        );

                    const confirm =
                        this.createButton(
                            'Load',
                            'preload-editor-button-primary',
                            () => {
                                const value =
                                    String(
                                        input.val() ||
                                        ''
                                    ).trim();

                                if (!value) return;

                                overlay.remove();
                                resolve(value);
                            }
                        );

                    buttons.append(
                        cancel,
                        confirm
                    );

                    box.append(
                        input,
                        buttons
                    );

                    overlay.append(box);
                    $(document.body)
                        .append(overlay);

                    input.trigger('focus');

                    input.on(
                        'keydown.preloadEditor',
                        event => {
                            if (
                                event.key ===
                                'Enter'
                            ) {
                                confirm.trigger(
                                    'click'
                                );
                            }

                            if (
                                event.key ===
                                'Escape'
                            ) {
                                cancel.trigger(
                                    'click'
                                );
                            }
                        }
                    );
                }
            );
        },

        async loadDefinition(
            title,
            source
        ) {
            const content =
                this.extractIncludeonly(
                    source
                );

            let config =
                this.emptyConfig();

            const configTitle =
                title.replace(/\/+$/, '') +
                '/config.json';

            const configPage =
                await this.getPage(
                    configTitle
                );

            if (configPage) {
                try {
                    config =
                        JSON.parse(
                            configPage.content
                        );
                } catch (error) {
                    throw new Error(
                        'The existing config.json contains invalid JSON: ' +
                        error.message
                    );
                }
            }

            const analysis =
                this.analyzePreload(
                    content
                );

            config =
                this.prepareConfigForVariables(
                    config,
                    analysis
                );

            this.state = {
                preloadTitle: title,
                preloadSource: source,
                preloadContent: source,
                config,
                variables:
                    analysis.variables,
                conditions:
                    analysis.conditions,
                selectedVariable:
                    analysis.variables.includes('PAGE')
                        ? 'PAGE'
                        : (
                            analysis.variables[0] ||
                            'PAGE'
                        ),
                mode: 'edit',
                dirty: false
            };

            this.renderEditor();
        },

        // Editor

        renderEditor() {
            this.destroyEditor();
            this.workspace.empty();

            const layout =
                $('<div>')
                    .addClass(
                        'preload-editor-layout'
                    );

            const left =
                $('<div>')
                    .addClass(
                        'preload-editor-left'
                    );

            const right =
                $('<div>')
                    .addClass(
                        'preload-editor-right'
                    );

            const editorSection =
                this.createSection(
                    'Preload',
                    'preload-editor-main-section'
                );

            const meta =
                $('<div>')
                    .addClass(
                        'preload-editor-meta'
                    );

            $('<strong>')
                .text(
                    this.state.preloadTitle ||
                    'New preload'
                )
                .appendTo(meta);

            if (
                this.state.mode ===
                'new'
            ) {
                $('<span>')
                    .addClass(
                        'preload-editor-badge'
                    )
                    .text('NEW')
                    .appendTo(meta);
            }

            editorSection.append(meta);

            editorSection.append(
                this.renderEditorTools()
            );

            const textarea =
                this.textarea(
                    this.state.preloadContent
                )
                    .attr(
                        'id',
                        'preload-editor-content'
                    )
                    .addClass(
                        'preload-editor-content'
                    );

            const editorMount =
                $('<div>')
                    .addClass(
                        'preload-editor-codemirror-mount'
                    )
                    .append(textarea);

            editorSection.append(
                editorMount
            );

            left.append(editorSection);

            /*
             * RIGHT PANEL
             *
             * Analysis is intentionally first.
             * Variables are now only a live list.
             * One configuration is displayed at a time.
             */

            const analysisSection =
                this.createSection(
                    'Analysis'
                );

            const analysisContainer =
                $('<div>')
                    .addClass(
                        'preload-editor-analysis'
                    );

            analysisSection.append(
                analysisContainer
            );

            const variablesSection =
                this.createSection(
                    'Variables'
                );

            const variableContainer =
                $('<div>')
                    .addClass(
                        'preload-editor-variables'
                    );

            variablesSection.append(
                variableContainer
            );

            const configurationSection =
                this.createSection(
                    'Variable configuration'
                );

            const configurationContainer =
                $('<div>')
                    .addClass(
                        'preload-editor-variable-configuration'
                    );

            configurationSection.append(
                configurationContainer
            );

            const configSection =
                this.createSection(
                    'Generated configuration'
                );

            const configPreview =
                $('<pre>')
                    .addClass(
                        'preload-editor-config-preview'
                    );

            configSection.append(
                configPreview
            );

            const actions =
                $('<div>')
                    .addClass(
                        'preload-editor-actions'
                    );

            actions.append(
                this.createButton(
                    'Save Preload + Config',
                    'preload-editor-button-primary',
                    () => this.saveAll()
                ),
                this.createButton(
                    'Save Preload Only',
                    '',
                    () => this.savePreloadOnly()
                )
            );

            right.append(
                analysisSection,
                variablesSection,
                configurationSection,
                configSection,
                actions
            );

            layout.append(
                left,
                right
            );

            this.workspace.append(
                layout
            );

            this.reanalyze();

            this.renderVariables(
                variableContainer
            );

            this.renderAnalysis(
                analysisContainer
            );

            this.renderVariableConfiguration(
                configurationContainer
            );

            this.renderConfigPreview(
                configPreview
            );

            this.updateEditorTools();

            this.mountCodeMirror(
                textarea.get(0)
            ).catch(error => {
                console.error(
                    'Preload Editor CodeMirror:',
                    error
                );

                this.setStatus(
                    error.message ||
                        'Could not initialize CodeMirror.',
                    'error'
                );
            });
        },

        reanalyze() {
            const source =
                this.getEditorContent();

            const content =
                this.extractIncludeonly(
                    source
                );

            const analysis =
                this.analyzePreload(
                    content
                );

            this.state.preloadContent =
                source;

            this.state.variables =
                analysis.variables;

            this.state.conditions =
                analysis.conditions;

            this.state.config =
                this.prepareConfigForVariables(
                    this.state.config ||
                        this.emptyConfig(),
                    analysis
                );

            this.analysis =
                analysis;

            /*
             * PAGE is always available.
             * If the selected variable disappears,
             * move the focus to PAGE or the first
             * currently-used variable.
             */
            const available =
                ['PAGE'].concat(
                    analysis.variables.filter(
                        name => name !== 'PAGE'
                    )
                );

            if (
                !available.includes(
                    this.state.selectedVariable
                )
            ) {
                this.state.selectedVariable =
                    available[0] || 'PAGE';
            }
        },

        renderAnalysis(container) {
            container.empty();

            const analysis =
                this.analysis ||
                this.analyzePreload(
                    this.extractIncludeonly(
                        this.getEditorContent()
                    )
                );

            const variableCount =
                analysis.variables.length;

            const conditionCount =
                analysis.conditions.length;

            const configuredCount =
                Object.keys(
                    this.state.config &&
                    this.state.config.fields
                        ? this.state.config.fields
                        : {}
                ).length;

            const summary =
                $('<div>')
                    .addClass(
                        'preload-editor-analysis-summary'
                    );

            const createMetric =
                (value, label) =>
                    $('<div>')
                        .addClass(
                            'preload-editor-analysis-metric'
                        )
                        .append(
                            $('<strong>')
                                .addClass(
                                    'preload-editor-analysis-value'
                                )
                                .text(value),
                            $('<span>')
                                .addClass(
                                    'preload-editor-analysis-label'
                                )
                                .text(label)
                        );

            summary.append(
                createMetric(
                    variableCount,
                    variableCount === 1
                        ? 'variable'
                        : 'variables'
                ),
                createMetric(
                    conditionCount,
                    conditionCount === 1
                        ? 'condition marker'
                        : 'condition markers'
                ),
                createMetric(
                    configuredCount,
                    configuredCount === 1
                        ? 'configured field'
                        : 'configured fields'
                )
            );

            container.append(
                summary
            );

            if (
                analysis.conditionVariables.length
            ) {
                container.append(
                    $('<div>')
                        .addClass(
                            'preload-editor-analysis-note'
                        )
                        .text(
                            'Condition variables: ' +
                            analysis.conditionVariables.join(
                                ', '
                            )
                        )
                );
            }

            const validation =
                this.validateConfig(
                    this.state.config,
                    analysis
                );

            if (
                validation.errors.length
            ) {
                const errors =
                    $('<ul>')
                        .addClass(
                            'preload-editor-validation-errors'
                        );

                validation.errors.forEach(
                    error => {
                        $('<li>')
                            .text(error)
                            .appendTo(errors);
                    }
                );

                container.append(
                    errors
                );
            }

            if (
                validation.warnings.length
            ) {
                const warnings =
                    $('<ul>')
                        .addClass(
                            'preload-editor-validation-warnings'
                        );

                validation.warnings.forEach(
                    warning => {
                        $('<li>')
                            .text(warning)
                            .appendTo(warnings);
                    }
                );

                container.append(
                    warnings
                );
            }

            if (
                !validation.errors.length &&
                !validation.warnings.length
            ) {
                container.append(
                    $('<div>')
                        .addClass(
                            'preload-editor-validation-success'
                        )
                        .text(
                            'Preload and configuration are in sync.'
                        )
                );
            }
        },

        renderAnalysisBySelector() {
            const container =
                this.root &&
                this.root.find(
                    '.preload-editor-analysis'
                );

            if (
                container &&
                container.length
            ) {
                this.renderAnalysis(
                    container
                );
            }
        },

        /*
         * Variable list
         *
         * This replaces the old behaviour where every
         * variable rendered its entire configuration card.
         */
        renderVariables(container) {
            container.empty();

            const analysis =
                this.analysis ||
                this.analyzePreload(
                    this.extractIncludeonly(
                        this.getEditorContent()
                    )
                );

            const variables =
                analysis.variables.slice();

            const ordered = ['PAGE'];

            variables.forEach(name => {
                if (
                    name !== 'PAGE' &&
                    !ordered.includes(name)
                ) {
                    ordered.push(name);
                }
            });

            const list =
                $('<div>')
                    .addClass(
                        'preload-editor-variable-list'
                    );

            ordered.forEach(name => {
                const isSelected =
                    name ===
                    this.state.selectedVariable;

                const isUsed =
                    analysis.variables.includes(
                        name
                    );

                const item =
                    $('<button>')
                        .attr({
                            type: 'button',
                            'data-variable': name
                        })
                        .addClass(
                            'preload-editor-variable-item'
                        )
                        .toggleClass(
                            'is-selected',
                            isSelected
                        )
                        .on(
                            'click.preloadEditor',
                            () =>
                                this.selectVariable(
                                    name
                                )
                        );

                const nameLabel =
                    $('<span>')
                        .addClass(
                            'preload-editor-variable-name'
                        )
                        .text(name);

                item.append(
                    nameLabel
                );

                if (name === 'PAGE') {
                    item.append(
                        $('<span>')
                            .addClass(
                                'preload-editor-badge'
                            )
                            .text('AUTOMATIC')
                    );
                } else if (!isUsed) {
                    item.append(
                        $('<span>')
                            .addClass(
                                'preload-editor-badge is-warning'
                            )
                            .text('UNUSED')
                    );
                }

                list.append(item);
            });

            container.append(list);

            if (!ordered.length) {
                container.append(
                    $('<div>')
                        .addClass(
                            'preload-editor-empty'
                        )
                        .text(
                            'No variables found in the preload.'
                        )
                );
            }
        },

        renderVariablesBySelector() {
            const container =
                this.root &&
                this.root.find(
                    '.preload-editor-variables'
                );

            if (
                container &&
                container.length
            ) {
                this.renderVariables(
                    container
                );
            }
        },

        /*
         * Select a variable from the list and display
         * only its configuration.
         */
        selectVariable(name) {
            name =
                String(name || '')
                    .trim()
                    .toUpperCase();

            if (!name) return;

            const available =
                ['PAGE'].concat(
                    (
                        this.analysis &&
                        this.analysis.variables
                            ? this.analysis.variables
                            : []
                    ).filter(
                        variable =>
                            variable !== 'PAGE'
                    )
                );

            if (!available.includes(name)) {
                return;
            }

            this.state.selectedVariable =
                name;

            this.renderVariablesBySelector();
            this.renderVariableConfigurationBySelector();

        },

        renderVariableConfigurationBySelector() {
            const container =
                this.root &&
                this.root.find(
                    '.preload-editor-variable-configuration'
                );

            if (
                container &&
                container.length
            ) {
                this.renderVariableConfiguration(
                    container
                );
            }
        },

        renderVariableConfiguration(container) {
            container.empty();

            const analysis =
                this.analysis ||
                this.analyzePreload(
                    this.extractIncludeonly(
                        this.getEditorContent()
                    )
                );

            const name =
                this.state.selectedVariable ||
                'PAGE';

            const fields =
                this.state.config &&
                this.state.config.fields
                    ? this.state.config.fields
                    : {};

            const field =
                fields[name] ||
                this.createDefaultField(
                    name,
                    analysis
                );

            if (name === 'PAGE') {
                container.append(
                    this.createAutomaticPageCard(
                        field
                    )
                );

                return;
            }

            container.append(
                this.createVariableCard(
                    name,
                    field,
                    analysis
                )
            );
        },

        /*
         * PAGE is precompiled/automatic.
         *
         * It remains selectable so the user can inspect
         * what PAGE represents, but its configuration
         * cannot be edited.
         */
        createAutomaticPageCard(field) {
            const card =
                $('<div>')
                    .addClass(
                        'preload-editor-variable preload-editor-variable-automatic'
                    )
                    .attr(
                        'data-variable',
                        'PAGE'
                    );

            const header =
                $('<div>')
                    .addClass(
                        'preload-editor-variable-header'
                    );

            header.append(
                $('<h3>').text('PAGE'),
                $('<span>')
                    .addClass(
                        'preload-editor-badge'
                    )
                    .text('AUTOMATIC')
            );

            card.append(header);

            $('<p>')
                .addClass(
                    'preload-editor-analysis-note'
                )
                .text(
                    'PAGE is a precompiled automatic variable. It is always available and is not edited like normal variables.'
                )
                .appendTo(card);

            const label =
                this.textInput(
                    field.label || 'Page Name'
                ).prop(
                    'disabled',
                    true
                );

            const description =
                this.textarea(
                    field.description || 'Name of the page.'
                )
                    .addClass(
                        'preload-editor-small-textarea'
                    )
                    .prop(
                        'disabled',
                        true
                    );

            const type =
                this.textInput(
                    field.type || 'page'
                ).prop(
                    'disabled',
                    true
                );

            const required =
                this.checkbox(
                    field.required !== false
                ).prop(
                    'disabled',
                    true
                );

            const namespace =
                this.textInput(
                    field.namespace || 'Main'
                ).prop(
                    'disabled',
                    true
                );

            const allowNew =
                this.checkbox(
                    field['allow-new'] === true
                ).prop(
                    'disabled',
                    true
                );

            card.append(
                this.fieldRow(
                    'Label',
                    label
                ),
                this.fieldRow(
                    'Description',
                    description
                ),
                this.fieldRow(
                    'Type',
                    type
                ),
                this.fieldRow(
                    'Required',
                    required
                ),
                this.fieldRow(
                    'Namespace',
                    namespace
                ),
                this.fieldRow(
                    'Allow new page',
                    allowNew
                )
            );

            return card;
        },

        createVariableCard(
            name,
            field,
            analysis
        ) {
            const card =
                $('<div>')
                    .addClass(
                        'preload-editor-variable'
                    )
                    .attr(
                        'data-variable',
                        name
                    );

            const header =
                $('<div>')
                    .addClass(
                        'preload-editor-variable-header'
                    );

            header.append(
                $('<h3>').text(name)
            );

            if (name === 'PAGE') {
                header.append(
                    $('<span>')
                        .addClass(
                            'preload-editor-badge'
                        )
                        .text('AUTOMATIC')
                );
            } else if (
                !analysis.variables.includes(name)
            ) {
                header.append(
                    $('<span>')
                        .addClass(
                            'preload-editor-badge is-warning'
                        )
                        .text('UNUSED')
                );
            }

            card.append(header);

            const label =
                this.textInput(
                    field.label || ''
                );

            label.on(
                'input.preloadEditor',
                () => {
                    field.label =
                        label.val();

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Label',
                    label
                )
            );

            const description =
                this.textarea(
                    field.description || ''
                ).addClass(
                    'preload-editor-small-textarea'
                );

            description.on(
                'input.preloadEditor',
                () => {
                    field.description =
                        description.val();

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Description',
                    description
                )
            );

            const types = [
                ['text', 'Text'],
                ['textarea', 'Textarea'],
                ['number', 'Number'],
                ['boolean', 'Boolean'],
                ['select', 'Select'],
                [
                    'multiselect',
                    'Multi-select'
                ],
                ['page', 'Page'],
                ['user', 'User'],
                ['date', 'Date']
            ];

            const typeSelect =
                this.select(
                    types.map(
                        ([value, label]) => ({
                            value,
                            label
                        })
                    ),
                    field.type || 'text'
                );

            typeSelect.on(
                'change.preloadEditor',
                () => {
                    field.type =
                        typeSelect.val();

                    this.markDirty();

                    this.renderVariableConfigurationBySelector();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Type',
                    typeSelect
                )
            );

            const required =
                this.checkbox(
                    field.required === true
                );

            required.on(
                'change.preloadEditor',
                () => {
                    field.required =
                        required.prop(
                            'checked'
                        );

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Required',
                    required
                )
            );

            const placeholder =
                this.textInput(
                    field.placeholder || ''
                );

            placeholder.on(
                'input.preloadEditor',
                () => {
                    const value =
                        placeholder.val();

                    if (value) {
                        field.placeholder =
                            value;
                    } else {
                        delete field.placeholder;
                    }

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Placeholder',
                    placeholder
                )
            );

            const defaultInput =
                this.textInput(
                    field.default === undefined
                        ? ''
                        : field.default
                );

            defaultInput.on(
                'input.preloadEditor',
                () => {
                    const value =
                        defaultInput.val();

                    if (value) {
                        field.default =
                            value;
                    } else {
                        delete field.default;
                    }

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Default',
                    defaultInput,
                    'For text-like fields this is used as a placeholder. For select fields it is the empty/default option.'
                )
            );

            if (
                field.type === 'textarea'
            ) {
                const maxRows =
                    this.textInput(
                        field.maxRows || ''
                    ).attr(
                        'type',
                        'number'
                    );

                maxRows.on(
                    'input.preloadEditor',
                    () => {
                        const value =
                            parseInt(
                                maxRows.val(),
                                10
                            );

                        if (
                            Number.isFinite(
                                value
                            ) &&
                            value > 0
                        ) {
                            field.maxRows =
                                value;
                        } else {
                            delete field.maxRows;
                        }

                        this.markDirty();
                        this.renderConfigPreviewBySelector();
                    }
                );

                card.append(
                    this.fieldRow(
                        'Maximum rows',
                        maxRows
                    )
                );
            }

            if (
                field.type === 'select' ||
                field.type === 'multiselect'
            ) {
                this.renderSelectConfiguration(
                    card,
                    field
                );
            }

            return card;
        },

        renderSelectConfiguration(
            card,
            field
        ) {
            const source =
                this.textInput(
                    field.source || '',
                    'category:Example'
                );

            source.on(
                'input.preloadEditor',
                () => {
                    const value =
                        source.val();

                    if (value) {
                        field.source = value;
                    } else {
                        delete field.source;
                    }

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Source',
                    source,
                    'Currently supported source format: category:Category Name'
                )
            );

            const sourcePrefix =
                this.textInput(
                    field['source-prefix'] || ''
                );

            sourcePrefix.on(
                'input.preloadEditor',
                () => {
                    const value =
                        sourcePrefix.val();

                    if (value) {
                        field['source-prefix'] =
                            value;
                    } else {
                        delete field[
                            'source-prefix'
                        ];
                    }

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Source prefix',
                    sourcePrefix,
                    'Only source values beginning with this text are included.'
                )
            );

            const excludeCategory =
                this.textInput(
                    field.exclude &&
                    field.exclude.category ||
                    ''
                );

            excludeCategory.on(
                'input.preloadEditor',
                () => {
                    const value =
                        excludeCategory.val();

                    if (value) {
                        field.exclude =
                            Object.assign(
                                {},
                                field.exclude || {},
                                {
                                    category:
                                        value
                                }
                            );
                    } else if (
                        field.exclude
                    ) {
                        delete field.exclude.category;

                        if (
                            !Object.keys(
                                field.exclude
                            ).length
                        ) {
                            delete field.exclude;
                        }
                    }

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Exclude category',
                    excludeCategory
                )
            );

            card.append(
                this.createTransformControls(
                    field,
                    'value',
                    'Value transformation'
                ),
                this.createTransformControls(
                    field,
                    'label',
                    'Label transformation'
                )
            );

            const optionsValue =
                Array.isArray(field.options)
                    ? field.options
                        .map(option => {
                            if (
                                typeof option ===
                                'string'
                            ) {
                                return option;
                            }

                            return (
                                String(
                                    option.value ||
                                    ''
                                ) +
                                ' | ' +
                                String(
                                    option.label ||
                                    option.value ||
                                    ''
                                )
                            );
                        })
                        .join('\n')
                    : '';

            const options =
                this.textarea(
                    optionsValue
                ).addClass(
                    'preload-editor-small-textarea'
                );

            options.on(
                'input.preloadEditor',
                () => {
                    const lines =
                        options
                            .val()
                            .split('\n')
                            .map(
                                line =>
                                    line.trim()
                            )
                            .filter(Boolean);

                    if (!lines.length) {
                        delete field.options;
                    } else {
                        field.options =
                            lines.map(line => {
                                const parts =
                                    line.split(
                                        /\s*\|\s*/
                                    );

                                if (
                                    parts.length ===
                                    1
                                ) {
                                    return parts[0];
                                }

                                return {
                                    value:
                                        parts[0],
                                    label:
                                        parts
                                            .slice(1)
                                            .join(
                                                ' | '
                                            )
                                };
                            });
                    }

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                }
            );

            card.append(
                this.fieldRow(
                    'Manual options',
                    options,
                    'One per line. Optional label format: value | label. Leave empty when using a source.'
                )
            );
        },

        createTransformControls(
            field,
            property,
            title
        ) {
            const wrapper =
                $('<div>')
                    .addClass(
                        'preload-editor-transform'
                    );

            $('<h4>')
                .text(title)
                .appendTo(wrapper);

            const existing =
                field[property] &&
                typeof field[property] ===
                    'object'
                    ? field[property]
                    : {};

            const transform =
                this.select(
                    [
                        {
                            value: '',
                            label:
                                'No transformation'
                        },
                        {
                            value:
                                'remove-prefix',
                            label:
                                'Remove prefix'
                        },
                        {
                            value:
                                'remove-suffix',
                            label:
                                'Remove suffix'
                        },
                        {
                            value: 'replace',
                            label: 'Replace'
                        }
                    ],
                    existing.transform || ''
                );

            const prefix =
                this.textInput(
                    existing.prefix || ''
                );

            const suffix =
                this.textInput(
                    existing.suffix || ''
                );

            const from =
                this.textInput(
                    existing.from || ''
                );

            const to =
                this.textInput(
                    existing.to || ''
                );

            const controls =
                $('<div>')
                    .addClass(
                        'preload-editor-transform-controls'
                    );

            const prefixRow =
                this.fieldRow(
                    'Prefix',
                    prefix
                );

            const suffixRow =
                this.fieldRow(
                    'Suffix',
                    suffix
                );

            const fromRow =
                this.fieldRow(
                    'From',
                    from
                );

            const toRow =
                this.fieldRow(
                    'To',
                    to
                );

            const renderInputs =
                () => {
                    const type =
                        transform.val();

                    prefixRow.toggle(
                        type ===
                            'remove-prefix'
                    );

                    suffixRow.toggle(
                        type ===
                            'remove-suffix'
                    );

                    fromRow.toggle(
                        type === 'replace'
                    );

                    toRow.toggle(
                        type === 'replace'
                    );
                };

            const update =
                () => {
                    const type =
                        transform.val();

                    let object = null;

                    if (
                        type ===
                            'remove-prefix' &&
                        prefix.val()
                    ) {
                        object = {
                            transform: type,
                            prefix:
                                prefix.val()
                        };
                    } else if (
                        type ===
                            'remove-suffix' &&
                        suffix.val()
                    ) {
                        object = {
                            transform: type,
                            suffix:
                                suffix.val()
                        };
                    } else if (
                        type === 'replace' &&
                        from.val()
                    ) {
                        object = {
                            transform: type,
                            from: from.val(),
                            to: to.val()
                        };
                    }

                    if (object) {
                        field[property] =
                            object;
                    } else {
                        delete field[property];
                    }

                    this.markDirty();
                    this.renderConfigPreviewBySelector();
                };

            transform.on(
                'change.preloadEditor',
                () => {
                    update();
                    renderInputs();
                }
            );

            [
                prefix,
                suffix,
                from,
                to
            ].forEach(input => {
                input.on(
                    'input.preloadEditor',
                    update
                );
            });

            controls.append(
                this.fieldRow(
                    'Transformation',
                    transform
                ),
                prefixRow,
                suffixRow,
                fromRow,
                toRow
            );

            renderInputs();

            wrapper.append(
                controls
            );

            return wrapper;
        },

        // Config output

        getCleanConfig() {
            const config =
                JSON.parse(
                    JSON.stringify(
                        this.state.config
                    )
                );

            const fields =
                config.fields || {};

            const orderedFields = {};

            // PAGE is always first and automatic.
            orderedFields.PAGE =
                this.getAutomaticPageField();

            Object.keys(fields)
                .filter(
                    name =>
                        name.toUpperCase() !==
                        'PAGE'
                )
                .forEach(name => {
                    orderedFields[name] =
                        fields[name];
                });

            config.fields =
                orderedFields;

            return config;
        },

        getConfigJSON() {
            return JSON.stringify(
                this.getCleanConfig(),
                null,
                4
            );
        },

        renderConfigPreview(container) {
            if (container) {
                container.text(
                    this.getConfigJSON()
                );
            }
        },

        renderConfigPreviewBySelector() {
            const preview =
                this.root &&
                this.root.find(
                    '.preload-editor-config-preview'
                );

            if (
                preview &&
                preview.length
            ) {
                this.renderConfigPreview(
                    preview
                );
            }

            this.renderAnalysisBySelector();
        },

        markDirty() {
            this.state.dirty = true;
        },

        // Save

        async savePreloadOnly() {
            let title =
                String(
                    this.state.preloadTitle ||
                    ''
                ).trim();

            if (!title) {
                const result =
                    await this.createPromptDialog(
                        'Preload title',
                        'Enter the full title for the preload.'
                    );

                if (!result) return;

                title = result;
                this.state.preloadTitle =
                    title;
            }

            this.state.preloadContent =
                this.getEditorContent();

            const validation =
                this.validateBeforeSave();

            if (
                validation.errors.length
            ) {
                this.showValidationErrors(
                    validation
                );

                return;
            }

            this.setStatus(
                'Saving preload...',
                'loading'
            );

            try {
                const exists =
                    await this.pageExists(
                        title
                    );

                await this.savePage(
                    title,
                    this.state.preloadContent,
                    exists
                        ? 'Updated preload with Preload Editor'
                        : 'Created preload with Preload Editor',
                    !exists
                );

                this.state.mode =
                    'edit';

                this.state.dirty =
                    false;

                this.setStatus(
                    'Preload saved successfully.',
                    'success'
                );

                mw.notify(
                    'Preload saved.',
                    {
                        type: 'success'
                    }
                );
            } catch (error) {
                console.error(
                    'Preload Editor save:',
                    error
                );

                this.setStatus(
                    error.message ||
                        'Could not save preload.',
                    'error'
                );

                mw.notify(
                    error.message ||
                        'Could not save preload.',
                    {
                        type: 'error'
                    }
                );
            }
        },

        async saveAll() {
            let title =
                String(
                    this.state.preloadTitle ||
                    ''
                ).trim();

            if (!title) {
                const result =
                    await this.createPromptDialog(
                        'Preload title',
                        'Enter the full title for the preload.'
                    );

                if (!result) return;

                title = result;
                this.state.preloadTitle =
                    title;
            }

            this.state.preloadContent =
                this.getEditorContent();

            const validation =
                this.validateBeforeSave();

            if (
                validation.errors.length
            ) {
                this.showValidationErrors(
                    validation
                );

                return;
            }

            const configTitle =
                title.replace(
                    /\/+$/,
                    ''
                ) +
                '/config.json';

            this.setStatus(
                'Saving preload and config...',
                'loading'
            );

            try {
                const preloadExists =
                    await this.pageExists(
                        title
                    );

                await this.savePage(
                    title,
                    this.state.preloadContent,
                    preloadExists
                        ? 'Updated preload with Preload Editor'
                        : 'Created preload with Preload Editor',
                    !preloadExists
                );

                const configExists =
                    await this.pageExists(
                        configTitle
                    );

                await this.savePage(
                    configTitle,
                    this.getConfigJSON(),
                    configExists
                        ? 'Updated preload config with Preload Editor'
                        : 'Created preload config with Preload Editor',
                    !configExists
                );

                this.state.mode =
                    'edit';

                this.state.dirty =
                    false;

                this.state.preloadTitle =
                    title;

                this.setStatus(
                    'Preload and config saved successfully.',
                    'success'
                );

                mw.notify(
                    'Preload and config saved.',
                    {
                        type: 'success'
                    }
                );
            } catch (error) {
                console.error(
                    'Preload Editor save:',
                    error
                );

                this.setStatus(
                    error.message ||
                        'Could not save preload/config.',
                    'error'
                );

                mw.notify(
                    error.message ||
                        'Could not save preload/config.',
                    {
                        type: 'error'
                    }
                );
            }
        },

        validateBeforeSave() {
            const errors = [];
            const warnings = [];

            const title =
                String(
                    this.state.preloadTitle ||
                    ''
                ).trim();

            if (!title) {
                errors.push(
                    'A preload title is required.'
                );
            }

            if (
                title &&
                !/\/Preload$/i.test(title)
            ) {
                warnings.push(
                    'The title does not end with "/Preload".'
                );
            }

            const content =
                this.getEditorContent();

            this.state.preloadContent =
                content;

            if (!content.trim()) {
                errors.push(
                    'The preload cannot be empty.'
                );
            }

            if (
                !/<includeonly>/i.test(
                    content
                )
            ) {
                warnings.push(
                    'The preload does not contain an <includeonly> section.'
                );
            }

            if (
                !/<noinclude>/i.test(
                    content
                )
            ) {
                warnings.push(
                    'The preload does not contain a <noinclude> section.'
                );
            }

            const analysis =
                this.analyzePreload(
                    this.extractIncludeonly(
                        content
                    )
                );

            const configValidation =
                this.validateConfig(
                    this.state.config,
                    analysis
                );

            errors.push(
                ...configValidation.errors
            );

            warnings.push(
                ...configValidation.warnings
            );

            let depth = 0;

            analysis.conditions.forEach(
                condition => {
                    if (
                        condition.type ===
                        'if'
                    ) {
                        depth++;
                    } else if (
                        condition.type ===
                        'endif'
                    ) {
                        depth--;

                        if (depth < 0) {
                            errors.push(
                                'Found @endif without a matching @if.'
                            );

                            depth = 0;
                        }
                    } else if (
                        condition.type ===
                            'elseif' ||
                        condition.type ===
                            'else'
                    ) {
                        if (depth === 0) {
                            errors.push(
                                '@' +
                                condition.type +
                                ' exists outside an @if block.'
                            );
                        }
                    }
                }
            );

            if (depth > 0) {
                errors.push(
                    'One or more @if blocks are missing @endif.'
                );
            }

            return {
                errors,
                warnings,
                valid:
                    errors.length === 0
            };
        },

        showValidationErrors(
            validation
        ) {
            this.renderAnalysisBySelector();

            this.setStatus(
                validation.errors.join(' '),
                'error'
            );

            mw.notify(
                validation.errors.join('\n'),
                {
                    type: 'error'
                }
            );
        }
    };

    mw.PreloadEditor =
        PreloadEditor;

    $(function () {
        if (
            mw.config.get('wgPageName') !==
            'Petit_Planet:Preload_Editor'
        ) {
            return;
        }

        PreloadEditor.init();
    });

}(mediaWiki, jQuery));