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MediaWiki:Gadget-PreloadEditor.js

MediaWiki interface page
Revision as of 07:37, 21 September 2026 by ReisuDesign (talk | contribs)

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(function (mw, $) {
    'use strict';

    const PreloadEditor = {
        version: '0.2.0',

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

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

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

        // API

        async getPage(title) {
            const api = new mw.Api();

            const response = await 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 api = new mw.Api();

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

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

        async savePage(title, content, summary, createOnly) {
            const api = new mw.Api();

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

            if (createOnly) {
                params.createonly = true;
            }

            return 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 = [];
            const conditions = this.findConditions(content);

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

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

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

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

            return variables;
        },

        analyzePreload(content) {
            const variables = this.findVariables(content);
            const conditions = this.findConditions(content);
            const conditionVariables =
                this.findConditionVariables(content);

            return {
                variables,
                conditions,
                conditionVariables
            };
        },

        // Config

        emptyConfig() {
            return {
                settings: {
                    incomplete: 'add-stub'
                },
                fields: {
                    PAGE: {
                        label: 'Page Name',
                        description: 'Name of the page.',
                        type: 'page',
                        required: true,
                        namespace: 'Main',
                        'allow-new': true
                    }
                }
            };
        },

        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 = {};
            }

            if (!config.fields.PAGE) {
                config.fields.PAGE = {
                    label: 'Page Name',
                    description: 'Name of the page.',
                    type: 'page',
                    required: true,
                    namespace: 'Main',
                    'allow-new': true
                };
            }

            return config;
        },

        createDefaultField(name, analysis) {
            const isConditionVariable =
                analysis.conditionVariables.includes(name);

            return {
                label: this.humanizeName(name),
                description: '',
                type: isConditionVariable ? '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 = {};

            fields.PAGE = existing.PAGE || {
                label: 'Page Name',
                description: 'Name of the page.',
                type: 'page',
                required: true,
                namespace: 'Main',
                'allow-new': true
            };

            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 (!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)
            ) {
                errors.push('"fields" must be an object.');

                return {
                    valid: false,
                    errors,
                    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 === 0,
                errors,
                warnings
            };
        },

        // Transformation helpers

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

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

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

                case 'replace':
                    return from === ''
                        ? null
                        : {
                            transform: 'replace',
                            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 === undefined ||
                        value === null
                            ? ''
                            : value,
                    placeholder: placeholder || ''
                })
                .addClass('preload-editor-input');
        },

        textarea(value) {
            return $('<textarea>')
                .val(
                    value === undefined ||
                    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;
                return;
            }

            const {
                view,
                inputHandler
            } = this.editor;

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

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

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

        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 = 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.renderAnalysisBySelector();
                        this.renderConfigPreviewBySelector();
                    };

                    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();

                    resolve(view);
                };

                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()
                );

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

            loader.append(loadRow);
            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: [],
                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: [],
                    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,
                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);

            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);

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

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

            configSection.append(configPreview);

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

            const save =
                this.createButton(
                    'Save Preload + Config',
                    'preload-editor-button-primary',
                    () => this.saveAll()
                );

            const savePreload =
                this.createButton(
                    'Save Preload Only',
                    '',
                    () => this.savePreloadOnly()
                );

            actions.append(save, savePreload);

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

            layout.append(left, right);
            this.workspace.append(layout);

            this.reanalyze();
            this.renderVariables(variableContainer);
            this.renderAnalysis(analysisContainer);
            this.renderConfigPreview(configPreview);

            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;
        },

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

            summary.append(
                $('<span>').text(
                    variableCount +
                    ' variable' +
                    (variableCount === 1 ? '' : 's')
                ),
                $('<span>').text(
                    conditionCount +
                    ' condition marker' +
                    (conditionCount === 1 ? '' : 's')
                )
            );

            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);
            }
        },

        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);
                }
            });

            Object.keys(
                this.state.config.fields || {}
            ).forEach(name => {
                const upper = name.toUpperCase();

                if (!ordered.includes(upper)) {
                    ordered.push(upper);
                }
            });

            ordered.forEach(name => {
                const field =
                    this.state.config.fields[name] ||
                    this.createDefaultField(
                        name,
                        analysis
                    );

                this.state.config.fields[name] = field;

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

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

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

        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();

                    card.replaceWith(
                        this.createVariableCard(
                            name,
                            field,
                            analysis
                        )
                    );

                    this.renderConfigPreviewBySelector();
                }
            );

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

            if (name === 'PAGE') {
                field.type = 'page';

                const required =
                    this.checkbox(
                        field.required !== false
                    );

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

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

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

                const namespace =
                    this.select(
                        [
                            {
                                value: 'Main',
                                label: 'Main'
                            },
                            {
                                value: 'Template',
                                label: 'Template'
                            },
                            {
                                value: 'File',
                                label: 'File'
                            },
                            {
                                value: 'Category',
                                label: 'Category'
                            },
                            {
                                value: 'User',
                                label: 'User'
                            }
                        ],
                        field.namespace || 'Main'
                    );

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

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

                card.append(
                    this.fieldRow(
                        'Namespace',
                        namespace
                    )
                );

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

                allowNew.on(
                    'change.preloadEditor',
                    () => {
                        field['allow-new'] =
                            allowNew.prop('checked');

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

                card.append(
                    this.fieldRow(
                        'Allow new page',
                        allowNew
                    )
                );

                return card;
            }

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

            if (fields.PAGE) {
                orderedFields.PAGE = fields.PAGE;
            }

            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) {
                return;
            }

            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 () {
        const title =
            mw.config.get('wgPageName');

        if (
            title !==
            'Petit_Planet:Preload_Editor'
        ) {
            return;
        }

        PreloadEditor.init();
    });

}(mediaWiki, jQuery));