/**
 * Simple Markdown Parser for Tinker Tickets
 * Supports basic markdown formatting without external dependencies
 */

function parseMarkdown(markdown) {
    if (!markdown) return '';

    let html = markdown;

    // Escape HTML first to prevent XSS
    html = html.replace(/&/g, '&')
               .replace(/</g, '&lt;')
               .replace(/>/g, '&gt;');

    // Ticket references (#123456789) - convert to clickable links
    html = html.replace(/#(\d{9})\b/g, '<a href="/ticket/$1" class="ticket-link-ref">#$1</a>');

    // Code blocks (```code```) - preserve content and don't process further
    const codeBlocks = [];
    html = html.replace(/```([\s\S]*?)```/g, function(match, code) {
        codeBlocks.push('<pre class="code-block"><code>' + code + '</code></pre>');
        return '%%CODEBLOCK' + (codeBlocks.length - 1) + '%%';
    });

    // Inline code (`code`) - preserve and don't process further
    const inlineCodes = [];
    html = html.replace(/`([^`]+)`/g, function(match, code) {
        inlineCodes.push('<code class="inline-code">' + code + '</code>');
        return '%%INLINECODE' + (inlineCodes.length - 1) + '%%';
    });

    // Tables (must be processed before other block elements)
    html = parseMarkdownTables(html);

    // Bold (**text** or __text__)
    html = html.replace(/\*\*(.+?)\*\*/g, '<strong>$1</strong>');
    html = html.replace(/__(.+?)__/g, '<strong>$1</strong>');

    // Italic (*text* or _text_)
    html = html.replace(/\*(.+?)\*/g, '<em>$1</em>');
    html = html.replace(/_(.+?)_/g, '<em>$1</em>');

    // Links [text](url) - only allow safe protocols
    html = html.replace(/\[([^\]]+)\]\(([^)]+)\)/g, function(match, text, url) {
        // Only allow http, https, mailto protocols
        if (/^(https?:|mailto:|\/)/i.test(url)) {
            return '<a href="' + url + '" target="_blank" rel="noopener noreferrer">' + text + '</a>';
        }
        // Block potentially dangerous protocols (javascript:, data:, etc.)
        return text;
    });

    // Auto-link bare URLs (http, https, ftp)
    html = html.replace(/(?<!["\'>])(\bhttps?:\/\/[^\s<>\[\]()]+)/g, '<a href="$1" target="_blank" rel="noopener noreferrer">$1</a>');

    // Headers (# H1, ## H2, etc.)
    html = html.replace(/^### (.+)$/gm, '<h3>$1</h3>');
    html = html.replace(/^## (.+)$/gm, '<h2>$1</h2>');
    html = html.replace(/^# (.+)$/gm, '<h1>$1</h1>');

    // Lists
    // Unordered lists (- item or * item)
    html = html.replace(/^\s*[-*]\s+(.+)$/gm, '<li>$1</li>');
    html = html.replace(/(<li>.*<\/li>)/s, '<ul>$1</ul>');

    // Ordered lists (1. item)
    html = html.replace(/^\s*\d+\.\s+(.+)$/gm, '<li>$1</li>');

    // Blockquotes (> text)
    html = html.replace(/^&gt;\s+(.+)$/gm, '<blockquote>$1</blockquote>');

    // Horizontal rules (--- or ***)
    html = html.replace(/^(?:---|___|\*\*\*)$/gm, '<hr>');

    // Line breaks (two spaces at end of line or double newline)
    html = html.replace(/  \n/g, '<br>');
    html = html.replace(/\n\n/g, '</p><p>');

    // Restore code blocks and inline code
    codeBlocks.forEach((block, i) => {
        html = html.replace('%%CODEBLOCK' + i + '%%', block);
    });
    inlineCodes.forEach((code, i) => {
        html = html.replace('%%INLINECODE' + i + '%%', code);
    });

    // Wrap in paragraph if not already wrapped
    if (!html.startsWith('<')) {
        html = '<p>' + html + '</p>';
    }

    return html;
}

/**
 * Parse markdown tables
 * Supports: | Header | Header |
 *           |--------|--------|
 *           | Cell   | Cell   |
 */
function parseMarkdownTables(html) {
    const lines = html.split('\n');
    const result = [];
    let inTable = false;
    let tableRows = [];

    for (let i = 0; i < lines.length; i++) {
        const line = lines[i].trim();

        // Check if line is a table row (starts and ends with |, or has | in the middle)
        if (line.match(/^\|.*\|$/) || line.match(/^[^|]+\|[^|]+/)) {
            // Check if next line is separator (|---|---|)
            const nextLine = lines[i + 1] ? lines[i + 1].trim() : '';
            const isSeparator = line.match(/^\|?[\s-:|]+\|[\s-:|]+\|?$/);

            if (!inTable && !isSeparator) {
                // Start of table - check if this is a header row
                if (nextLine.match(/^\|?[\s-:|]+\|[\s-:|]+\|?$/)) {
                    inTable = true;
                    tableRows.push({ type: 'header', content: line });
                    continue;
                }
            }

            if (inTable) {
                if (isSeparator) {
                    // Skip separator line
                    continue;
                }
                tableRows.push({ type: 'body', content: line });
                continue;
            }
        }

        // Not a table row - flush any accumulated table
        if (inTable && tableRows.length > 0) {
            result.push(buildTable(tableRows));
            tableRows = [];
            inTable = false;
        }
        result.push(lines[i]);
    }

    // Flush remaining table
    if (tableRows.length > 0) {
        result.push(buildTable(tableRows));
    }

    return result.join('\n');
}

/**
 * Build HTML table from parsed rows
 */
function buildTable(rows) {
    if (rows.length === 0) return '';

    let html = '<table class="markdown-table">';

    rows.forEach((row, index) => {
        const cells = row.content.split('|').filter(cell => cell.trim() !== '');
        const tag = row.type === 'header' ? 'th' : 'td';
        const wrapper = row.type === 'header' ? 'thead' : (index === 1 ? 'tbody' : '');

        if (wrapper === 'thead') html += '<thead>';
        if (wrapper === 'tbody') html += '<tbody>';

        html += '<tr>';
        cells.forEach(cell => {
            html += `<${tag}>${cell.trim()}</${tag}>`;
        });
        html += '</tr>';

        if (row.type === 'header') html += '</thead>';
    });

    html += '</tbody></table>';
    return html;
}

// Apply markdown rendering to all elements with data-markdown attribute
function renderMarkdownElements() {
    document.querySelectorAll('[data-markdown]').forEach(element => {
        const markdownText = element.getAttribute('data-markdown') || element.textContent;
        element.innerHTML = parseMarkdown(markdownText);
    });
}

// Apply markdown to description and comments on page load
document.addEventListener('DOMContentLoaded', renderMarkdownElements);

// Expose for manual use
window.parseMarkdown = parseMarkdown;
window.renderMarkdownElements = renderMarkdownElements;

// ========================================
// Rich Text Editor Toolbar Functions
// ========================================

/**
 * Insert markdown formatting around selection
 */
function insertMarkdownFormat(textareaId, prefix, suffix) {
    const textarea = document.getElementById(textareaId);
    if (!textarea) return;

    const start = textarea.selectionStart;
    const end = textarea.selectionEnd;
    const text = textarea.value;
    const selectedText = text.substring(start, end);

    // Insert formatting
    const newText = text.substring(0, start) + prefix + selectedText + suffix + text.substring(end);
    textarea.value = newText;

    // Set cursor position
    if (selectedText) {
        textarea.setSelectionRange(start + prefix.length, end + prefix.length);
    } else {
        textarea.setSelectionRange(start + prefix.length, start + prefix.length);
    }

    textarea.focus();

    // Trigger input event to update preview if enabled
    textarea.dispatchEvent(new Event('input', { bubbles: true }));
}

/**
 * Insert markdown at cursor position
 */
function insertMarkdownText(textareaId, text) {
    const textarea = document.getElementById(textareaId);
    if (!textarea) return;

    const start = textarea.selectionStart;
    const value = textarea.value;

    textarea.value = value.substring(0, start) + text + value.substring(start);
    textarea.setSelectionRange(start + text.length, start + text.length);
    textarea.focus();

    textarea.dispatchEvent(new Event('input', { bubbles: true }));
}

/**
 * Toolbar button handlers
 */
function toolbarBold(textareaId) {
    insertMarkdownFormat(textareaId, '**', '**');
}

function toolbarItalic(textareaId) {
    insertMarkdownFormat(textareaId, '_', '_');
}

function toolbarCode(textareaId) {
    const textarea = document.getElementById(textareaId);
    if (!textarea) return;

    const selectedText = textarea.value.substring(textarea.selectionStart, textarea.selectionEnd);

    // Use code block for multi-line, inline code for single line
    if (selectedText.includes('\n')) {
        insertMarkdownFormat(textareaId, '```\n', '\n```');
    } else {
        insertMarkdownFormat(textareaId, '`', '`');
    }
}

function toolbarLink(textareaId) {
    const textarea = document.getElementById(textareaId);
    if (!textarea) return;

    const selectedText = textarea.value.substring(textarea.selectionStart, textarea.selectionEnd);

    if (selectedText) {
        // Wrap selected text as link text
        insertMarkdownFormat(textareaId, '[', '](url)');
    } else {
        insertMarkdownText(textareaId, '[link text](url)');
    }
}

function toolbarList(textareaId) {
    const textarea = document.getElementById(textareaId);
    if (!textarea) return;

    const start = textarea.selectionStart;
    const text = textarea.value;

    // Find start of current line
    let lineStart = start;
    while (lineStart > 0 && text[lineStart - 1] !== '\n') {
        lineStart--;
    }

    // Insert list marker at beginning of line
    textarea.value = text.substring(0, lineStart) + '- ' + text.substring(lineStart);
    textarea.setSelectionRange(start + 2, start + 2);
    textarea.focus();

    textarea.dispatchEvent(new Event('input', { bubbles: true }));
}

function toolbarHeading(textareaId) {
    const textarea = document.getElementById(textareaId);
    if (!textarea) return;

    const start = textarea.selectionStart;
    const text = textarea.value;

    // Find start of current line
    let lineStart = start;
    while (lineStart > 0 && text[lineStart - 1] !== '\n') {
        lineStart--;
    }

    // Insert heading marker at beginning of line
    textarea.value = text.substring(0, lineStart) + '## ' + text.substring(lineStart);
    textarea.setSelectionRange(start + 3, start + 3);
    textarea.focus();

    textarea.dispatchEvent(new Event('input', { bubbles: true }));
}

function toolbarQuote(textareaId) {
    const textarea = document.getElementById(textareaId);
    if (!textarea) return;

    const start = textarea.selectionStart;
    const text = textarea.value;

    // Find start of current line
    let lineStart = start;
    while (lineStart > 0 && text[lineStart - 1] !== '\n') {
        lineStart--;
    }

    // Insert quote marker at beginning of line
    textarea.value = text.substring(0, lineStart) + '> ' + text.substring(lineStart);
    textarea.setSelectionRange(start + 2, start + 2);
    textarea.focus();

    textarea.dispatchEvent(new Event('input', { bubbles: true }));
}

/**
 * Create and insert toolbar HTML for a textarea
 */
function createEditorToolbar(textareaId, containerId) {
    const container = document.getElementById(containerId);
    if (!container) return;

    const toolbar = document.createElement('div');
    toolbar.className = 'editor-toolbar';
    toolbar.innerHTML = `
        <button type="button" data-toolbar-action="bold" data-textarea="${textareaId}" title="Bold (Ctrl+B)"><b>B</b></button>
        <button type="button" data-toolbar-action="italic" data-textarea="${textareaId}" title="Italic (Ctrl+I)"><i>I</i></button>
        <button type="button" data-toolbar-action="code" data-textarea="${textareaId}" title="Code">&lt;/&gt;</button>
        <span class="toolbar-separator"></span>
        <button type="button" data-toolbar-action="heading" data-textarea="${textareaId}" title="Heading">H</button>
        <button type="button" data-toolbar-action="list" data-textarea="${textareaId}" title="List">≡</button>
        <button type="button" data-toolbar-action="quote" data-textarea="${textareaId}" title="Quote">"</button>
        <span class="toolbar-separator"></span>
        <button type="button" data-toolbar-action="link" data-textarea="${textareaId}" title="Link">🔗</button>
    `;

    // Add event delegation for toolbar buttons
    toolbar.addEventListener('click', function(e) {
        const btn = e.target.closest('[data-toolbar-action]');
        if (!btn) return;

        const action = btn.dataset.toolbarAction;
        const targetId = btn.dataset.textarea;

        switch (action) {
            case 'bold': toolbarBold(targetId); break;
            case 'italic': toolbarItalic(targetId); break;
            case 'code': toolbarCode(targetId); break;
            case 'heading': toolbarHeading(targetId); break;
            case 'list': toolbarList(targetId); break;
            case 'quote': toolbarQuote(targetId); break;
            case 'link': toolbarLink(targetId); break;
        }
    });

    container.insertBefore(toolbar, container.firstChild);
}

// Expose toolbar functions globally
window.toolbarBold = toolbarBold;
window.toolbarItalic = toolbarItalic;
window.toolbarCode = toolbarCode;
window.toolbarLink = toolbarLink;
window.toolbarList = toolbarList;
window.toolbarHeading = toolbarHeading;
window.toolbarQuote = toolbarQuote;
window.createEditorToolbar = createEditorToolbar;
window.insertMarkdownFormat = insertMarkdownFormat;
window.insertMarkdownText = insertMarkdownText;

// ========================================
// Auto-link URLs in plain text (non-markdown)
// ========================================

/**
 * Convert plain text URLs to clickable links
 * Used for non-markdown comments
 */
function autoLinkUrls(text) {
    if (!text) return '';
    // Match URLs that aren't already in an href attribute
    return text.replace(/(?<!["\'>])(https?:\/\/[^\s<>\[\]()]+)/g,
        '<a href="$1" target="_blank" rel="noopener noreferrer" class="auto-link">$1</a>');
}

/**
 * Process all non-markdown comment elements to auto-link URLs
 */
function processPlainTextComments() {
    document.querySelectorAll('.comment-text:not([data-markdown])').forEach(element => {
        // Only process if not already processed
        if (element.dataset.linksProcessed) return;
        element.innerHTML = autoLinkUrls(element.innerHTML);
        element.dataset.linksProcessed = 'true';
    });
}

// Run on page load
document.addEventListener('DOMContentLoaded', function() {
    processPlainTextComments();
});

// Expose for manual use
window.autoLinkUrls = autoLinkUrls;
window.processPlainTextComments = processPlainTextComments;