const fs = require('fs');
const path = require('path');
const announcementIcons = require('#src/data/announcement-icons');

function mediaKind(mediaPath) {
  const ext = path.extname(mediaPath || '').toLowerCase();
  if (['.png', '.jpg', '.jpeg', '.gif', '.webp', '.bmp', '.svg'].includes(ext)) {
    return 'image';
  }
  if (['.mp4', '.webm', '.ogg'].includes(ext)) {
    return 'video';
  }
  if (ext === '.pdf') {
    return 'pdf';
  }
  return 'file';
}

function escapeHtml(value) {
  return String(value ?? '')
    .replace(/&/g, '&')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;')
    .replace(/"/g, '&quot;')
    .replace(/'/g, '&#39;');
}

function normalizeStyleAttributeValue(value) {
  return String(value || '')
    .replace(/&quot;/g, '"')
    .replace(/&#39;/g, "'")
    .replace(/&amp;quot;/g, '"')
    .replace(/&amp;#39;/g, "'");
}

function sanitizeFontFamily(value) {
  return String(value || '').replace(/[^a-zA-Z0-9 ,"-]/g, '').trim();
}

function sanitizeFontSize(value) {
  return Math.max(8, Number(value || 0) || 24);
}

function sanitizeTextColor(value, fallback) {
  const raw = String(value || '').trim();
  if (/^#[0-9a-fA-F]{6}$/.test(raw) || /^#[0-9a-fA-F]{3}$/.test(raw)) {
    return raw;
  }
  return fallback || '#000000';
}

const ALLOWED_RICH_TEXT_TAGS = ['a', 'b', 'blockquote', 'br', 'code', 'col', 'colgroup', 'div', 'em', 'figure', 'figcaption', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'hr', 'i', 'img', 'li', 'ol', 'p', 'pre', 'span', 'strong', 'sub', 'sup', 'table', 'tbody', 'td', 'th', 'thead', 'tr', 'u', 'ul'];

function sanitizeRichTextAttributes(tagName, attrText) {
  const allowedAttributes = {
    a: ['href', 'title', 'target', 'rel', 'class', 'style'],
    blockquote: ['class', 'style'],
    div: ['class', 'style'],
    figure: ['class', 'style'],
    figcaption: ['class', 'style'],
    h1: ['class', 'style'],
    h2: ['class', 'style'],
    h3: ['class', 'style'],
    h4: ['class', 'style'],
    h5: ['class', 'style'],
    h6: ['class', 'style'],
    img: ['src', 'alt', 'title', 'width', 'height', 'class', 'style', 'loading', 'decoding'],
    col: ['class', 'style', 'span', 'width'],
    colgroup: ['class', 'style', 'span'],
    li: ['class', 'style'],
    ol: ['class', 'style', 'start'],
    p: ['class', 'style'],
    pre: ['class', 'style'],
    span: ['class', 'style'],
    table: ['class', 'style'],
    td: ['class', 'style', 'colspan', 'rowspan'],
    th: ['class', 'style', 'colspan', 'rowspan', 'scope'],
    tr: ['class', 'style'],
    ul: ['class', 'style']
  };
  const allowed = allowedAttributes[tagName] || [];
  if (!allowed.length) {
    return '';
  }

  if (tagName === 'img') {
    const srcMatch = String(attrText || '').match(/\bsrc\s*=\s*("([^"]*)"|'([^']*)'|([^\s"'>/=`]+))/i);
    const srcValue = srcMatch ? String(srcMatch[2] !== undefined ? srcMatch[2] : srcMatch[3] !== undefined ? srcMatch[3] : srcMatch[4] !== undefined ? srcMatch[4] : '').trim() : '';
    if (!srcValue || !/^(?:https?:\/\/|\/media\/|\/assets\/|\/[^/]|data:image\/)/i.test(srcValue)) {
      return '';
    }
  }

  const attrs = [];
  String(attrText || '').replace(/([a-zA-Z0-9:-]+)(?:\s*=\s*("([^"]*)"|'([^']*)'|([^\s"'>/=`]+)))?/g, (_full, key, _valuePart, doubleQuoted, singleQuoted, bareValue) => {
    const lowerKey = String(key || '').toLowerCase();
    if (!allowed.includes(lowerKey)) {
      return '';
    }
    const value = doubleQuoted !== undefined ? doubleQuoted : singleQuoted !== undefined ? singleQuoted : bareValue !== undefined ? bareValue : '';
    if (lowerKey === 'href' && /^(?:\s*javascript:|\s*data:)/i.test(String(value || ''))) {
      return '';
    }
    if (lowerKey === 'style' && /(?:expression\s*\(|javascript:|url\s*\()/i.test(String(value || ''))) {
      return '';
    }
    if (lowerKey === 'target') {
      const targetValue = String(value || '').trim();
      if (targetValue === '_blank') {
        attrs.push(' target="_blank"');
        if (!attrs.includes(' rel="noreferrer noopener"')) {
          attrs.push(' rel="noreferrer noopener"');
        }
        return '';
      }
    }
    attrs.push(' ' + lowerKey + '="' + escapeHtml(lowerKey === 'style' ? normalizeStyleAttributeValue(value) : value) + '"');
    return '';
  });

  return attrs.join('');
}

function safeJsonForScript(value) {
  return JSON.stringify(value === undefined ? null : value).replace(/</g, '\\u003c');
}

function parseMaybeJson(value) {
  if (typeof value !== 'string') {
    return value;
  }
  const raw = value.trim();
  if (!raw) {
    return value;
  }
  if (raw[0] !== '{' && raw[0] !== '[') {
    return value;
  }
  try {
    return JSON.parse(raw);
  } catch (_error) {
    return value;
  }
}

function normalizeContentValue(value) {
  if (!value || typeof value !== 'object') {
    return {
      type: 'text',
      value: parseMaybeJson(value)
    };
  }
  const normalized = {};
  Object.keys(value).forEach(function (key) {
    normalized[key] = value[key];
  });
  if (normalized.value !== undefined) {
    normalized.value = parseMaybeJson(normalized.value);
  } else if (normalized.font_family !== undefined && normalized.font_family !== null) {
    normalized.font_family = sanitizeFontFamily(normalized.font_family);
  } else if (normalized.font_size !== undefined && normalized.font_size !== null) {
    normalized.font_size = sanitizeFontSize(normalized.font_size);
  } else if (normalized.font_color !== undefined && normalized.font_color !== null) {
    normalized.font_color = sanitizeTextColor(normalized.font_color);
  } else if (!normalized.type) {
    normalized.type = 'text';
  }
  return normalized;
}

function normalizeSlide(slide) {
  const normalized = {};
  Object.keys(slide || {}).forEach(function (key) {
    normalized[key] = slide[key];
  });
  normalized.content = {};
  const content = slide && slide.content && typeof slide.content === 'object' ? slide.content : {};
  Object.keys(content).forEach(function (regionKey) {
    normalized.content[regionKey] = normalizeContentValue(content[regionKey]);
  });
  return normalized;
}

function sanitizeRichText(html) {
  let output = String(html || '');
  output = output.replace(/<script[\s\S]*?<\/script>/gi, '');
  output = output.replace(/<style[\s\S]*?<\/style>/gi, '');
  return output.replace(/<[^>]+>/g, (tag) => {
    const match = tag.match(/^<\s*(\/?)\s*([a-z0-9]+)([\s\S]*?)(\/?)>$/i);
    if (!match) {
      return '';
    }
    const closing = Boolean(match[1]);
    const name = String(match[2] || '').toLowerCase();
    const attrText = String(match[3] || '');
    if (!ALLOWED_RICH_TEXT_TAGS.includes(name)) {
      return '';
    }
    if (closing) {
      return `</${name}>`;
    }
    return `<${name}${sanitizeRichTextAttributes(name, attrText)}>`;
  });
}

function renderEditorJsBlock(block) {
  if (!block || !block.type || !block.data) {
    return '';
  }

  if (block.type === 'header') {
    const level = Math.max(1, Math.min(6, Number(block.data.level || 2)));
    return '<h' + level + '>' + sanitizeRichText(block.data.text || '') + '</h' + level + '>';
  } else if (block.type === 'list') {
    const tag = block.data.style === 'ordered' ? 'ol' : 'ul';
    const items = Array.isArray(block.data.items) ? block.data.items : [];
    return '<' + tag + ' style="list-style-type:' + (tag === 'ol' ? 'decimal' : 'disc') + ';padding-left:1.4em;">' + items.map((item) => renderEditorJsListItem(item, tag)).join('') + '</' + tag + '>';
  } else if (block.type === 'delimiter') {
    return '<hr />';
  } else if (block.type === 'code') {
    return '<pre><code>' + escapeHtml(block.data.code || '') + '</code></pre>';
  } else if (block.type === 'table') {
    return renderEditorJsTable(block.data);
  } else if (block.type === 'paragraph') {
    return '<p>' + sanitizeRichText(block.data.text || '') + '</p>';
  }

  return '';
}

function renderEditorJsListItem(item, tag) {
  if (item && typeof item === 'object') {
    const content = item.content !== undefined ? item.content : (item.text !== undefined ? item.text : item.value !== undefined ? item.value : '');
    const children = Array.isArray(item.items) ? item.items : Array.isArray(item.subItems) ? item.subItems : Array.isArray(item.children) ? item.children : [];
    const nested = children.length ? '<' + tag + ' style="list-style-type:' + (tag === 'ol' ? 'decimal' : 'disc') + ';padding-left:1.4em;">' + children.map((child) => renderEditorJsListItem(child, tag)).join('') + '</' + tag + '>' : '';
    return '<li>' + sanitizeRichText(content || '') + nested + '</li>';
  }
  return '<li>' + sanitizeRichText(item || '') + '</li>';
}

function renderEditorJsTable(data) {
  const rows = Array.isArray(data.content) ? data.content : Array.isArray(data.rows) ? data.rows : [];
  if (!rows.length) {
    return '';
  }
  const hasHeadings = Boolean(data.withHeadings);
  const tableRows = rows.map(function (row, rowIndex) {
    const cells = Array.isArray(row) ? row : [];
    const cellTag = hasHeadings && rowIndex === 0 ? 'th' : 'td';
    const cellAttrs = cellTag === 'th' ? ' scope="col"' : '';
    return '<tr>' + cells.map(function (cell) {
      return '<' + cellTag + cellAttrs + '>' + sanitizeRichText(cell || '') + '</' + cellTag + '>';
    }).join('') + '</tr>';
  }).join('');
  return '<table class="ck-content-table">' + tableRows + '</table>';
}

function wrapRichTextParagraph(html) {
  const raw = String(html || '').trim();
  if (!raw) {
    return '';
  }
  if (/^<\s*(?:p|div|h[1-6]|ul|ol|pre|table|blockquote|figure|hr|li)\b/i.test(raw)) {
    return raw;
  }
  return '<p>' + raw + '</p>';
}

function renderEditorJsContent(value) {
  if (value && typeof value === 'object') {
    if (Array.isArray(value.blocks)) {
      return value.blocks.map(renderEditorJsBlock).join('');
    }
    if (value.value !== undefined) {
      return renderEditorJsContent(value.value);
    }
  }
  const raw = String(value || '');
  try {
    const parsed = JSON.parse(raw);
    if (parsed && Array.isArray(parsed.blocks)) {
      return parsed.blocks.map(renderEditorJsBlock).join('');
    }
  } catch (_error) {
    // fall through to legacy HTML rendering
  }
  return wrapRichTextParagraph(sanitizeRichText(raw));
}

function buildHtmlDocument(html) {
  const raw = String(html || '').trim();
  if (!raw) {
    return '';
  }

  if (/^<!doctype\b/i.test(raw) || /^<html\b/i.test(raw)) {
    return raw;
  }

  return '<!doctype html><html><head><style>html,body{margin:0;width:100%;height:100%;overflow:hidden;background:transparent;}</style></head><body>' + raw + '</body></html>';
}

function renderHtmlRegionContent(value) {
  const html = normalizeRenderableValue(value).trim();
  if (!html) {
    return '<div class="template-region-placeholder">HTML</div>';
  }
  return '<iframe class="template-region-html-frame" sandbox="" srcdoc="' + escapeHtml(buildHtmlDocument(html)) + '" title="HTML region" loading="eager" style="width:100%;height:100%;border:0;display:block;background:transparent;overflow:hidden;"></iframe>';
}

function normalizeRenderableValue(value) {
  if (value && typeof value === 'object') {
    if (value.value !== undefined) {
      return normalizeRenderableValue(value.value);
    }
    if (value.text !== undefined) {
      return normalizeRenderableValue(value.text);
    }
    if (value.html !== undefined) {
      return normalizeRenderableValue(value.html);
    }
    if (value.content !== undefined) {
      return normalizeRenderableValue(value.content);
    }
    return '';
  }

  return String(value === undefined || value === null ? '' : value);
}

function fitCanvasSize(canvasWidth, canvasHeight, maxWidth, maxHeight) {
  const width = Math.max(1, Number(canvasWidth || 0) || 1920);
  const height = Math.max(1, Number(canvasHeight || 0) || 1080);
  const viewportWidth = Math.max(1, Number(maxWidth || 0) || width);
  const viewportHeight = Math.max(1, Number(maxHeight || 0) || height);
  const scale = Math.min(viewportWidth / width, viewportHeight / height);
  return {
    width: Math.round(width * scale),
    height: Math.round(height * scale)
  };
}

const playerPageTemplatePath = path.join(__dirname, 'player-page.template.html');
const playerClientNameScriptPath = path.join(__dirname, 'player-client-name.script.html');
const playerPageOfflineScriptPath = path.join(__dirname, 'public', 'js', 'player-page-offline.js');
const playerPagePlaylistScriptPath = path.join(__dirname, 'public', 'js', 'player-page-playlist.js');
const playerPageCommandsScriptPath = path.join(__dirname, 'public', 'js', 'player-page-commands.js');
const playerPageRenderingScriptPath = path.join(__dirname, 'public', 'js', 'player-page-rendering.js');
const playerPagePlaybackScriptPath = path.join(__dirname, 'public', 'js', 'player-page-playback.js');
const playerAnnouncementTemplatesScriptPath = path.join(__dirname, 'public', 'js', 'player-announcement-templates.js');
const playerAnnouncementLowerThirdTemplatePath = path.join(__dirname, 'announcement-templates', 'lower-third.template.html');
const playerAnnouncementTopBannerTemplatePath = path.join(__dirname, 'announcement-templates', 'top-banner.template.html');
const playerAnnouncementFullscreenTemplatePath = path.join(__dirname, 'announcement-templates', 'fullscreen.template.html');
const playerPageAnnouncementsScriptPath = path.join(__dirname, 'player-page-announcements.js');
const playerPageScriptPath = path.join(__dirname, 'player-page.script.html');
const playerRegionScriptDir = path.join(__dirname, 'regions');
const playerOnboardingLandingScriptPath = path.join(__dirname, 'onboarding', 'player-onboarding-landing.script.html');
const playerOnboardingFormScriptPath = path.join(__dirname, 'onboarding', 'player-onboarding-form.script.html');
let playerPageTemplateCache = null;
let playerClientNameScriptCache = null;
let playerPageOfflineScriptCache = null;
let playerPagePlaylistScriptCache = null;
let playerPageCommandsScriptCache = null;
let playerPageRenderingScriptCache = null;
let playerPagePlaybackScriptCache = null;
let playerAnnouncementTemplatesScriptCache = null;
let playerAnnouncementTemplatesDataScriptCache = null;
let playerPageAnnouncementsScriptCache = null;
let playerPageScriptCache = null;
let playerRegionScriptsCache = null;
let playerOnboardingLandingScriptCache = null;
let playerOnboardingFormScriptCache = null;

function loadTemplate(filePath, cache) {
  const stat = fs.statSync(filePath);
  if (cache.value && cache.mtimeMs === stat.mtimeMs) {
    return cache.value;
  }
  const compiled = require('handlebars').compile(fs.readFileSync(filePath, 'utf8'));
  cache.value = compiled;
  cache.mtimeMs = stat.mtimeMs;
  return compiled;
}

function getPlayerPageTemplate() {
  return loadTemplate(playerPageTemplatePath, playerPageTemplateCache || (playerPageTemplateCache = {}));
}

function getPlayerClientNameScript() {
  return loadTemplate(playerClientNameScriptPath, playerClientNameScriptCache || (playerClientNameScriptCache = {}));
}

function getPlayerPageOfflineScript() {
  return loadTemplate(playerPageOfflineScriptPath, playerPageOfflineScriptCache || (playerPageOfflineScriptCache = {}));
}

function getPlayerPagePlaylistScript() {
  return loadTemplate(playerPagePlaylistScriptPath, playerPagePlaylistScriptCache || (playerPagePlaylistScriptCache = {}));
}

function getPlayerPageCommandsScript() {
  return loadTemplate(playerPageCommandsScriptPath, playerPageCommandsScriptCache || (playerPageCommandsScriptCache = {}));
}

function getPlayerPageRenderingScript() {
  return loadTemplate(playerPageRenderingScriptPath, playerPageRenderingScriptCache || (playerPageRenderingScriptCache = {}));
}

function getPlayerPagePlaybackScript() {
  return loadTemplate(playerPagePlaybackScriptPath, playerPagePlaybackScriptCache || (playerPagePlaybackScriptCache = {}));
}

function getPlayerAnnouncementTemplatesScript() {
  if (playerAnnouncementTemplatesScriptCache && playerAnnouncementTemplatesScriptCache.path === playerAnnouncementTemplatesScriptPath) {
    return playerAnnouncementTemplatesScriptCache.value;
  }

  const value = fs.readFileSync(playerAnnouncementTemplatesScriptPath, 'utf8').trim();
  playerAnnouncementTemplatesScriptCache = {
    path: playerAnnouncementTemplatesScriptPath,
    value: value
  };
  return value;
}

function getAnnouncementIconsDataScript() {
  return [
    '(function () {',
    '  window.pulseAnnouncementIconKeys = ' + safeJsonForScript(announcementIcons.ANNOUNCEMENT_ICON_KEYS) + ';',
    '  window.pulseAnnouncementDefaultIconKey = ' + safeJsonForScript(announcementIcons.DEFAULT_ANNOUNCEMENT_ICON) + ';',
    '}());'
  ].join('\n');
}

function loadAnnouncementTemplate(filePath) {
  return fs.readFileSync(filePath, 'utf8').trim();
}

function getPlayerAnnouncementTemplatesDataScript() {
  const templatePaths = [
    playerAnnouncementLowerThirdTemplatePath,
    playerAnnouncementTopBannerTemplatePath,
    playerAnnouncementFullscreenTemplatePath
  ];
  const signature = templatePaths.map(function (filePath) {
    return fs.statSync(filePath).mtimeMs;
  }).join('|');

  if (playerAnnouncementTemplatesDataScriptCache && playerAnnouncementTemplatesDataScriptCache.signature === signature) {
    return playerAnnouncementTemplatesDataScriptCache.value;
  }

  const value = [
    '(function () {',
    '  window.playerAnnouncementTemplates = {',
    '    lowerThird: ' + safeJsonForScript(loadAnnouncementTemplate(playerAnnouncementLowerThirdTemplatePath)) + ',',
    '    topBanner: ' + safeJsonForScript(loadAnnouncementTemplate(playerAnnouncementTopBannerTemplatePath)) + ',',
    '    fullscreen: ' + safeJsonForScript(loadAnnouncementTemplate(playerAnnouncementFullscreenTemplatePath)),
    '  };',
    '}());'
  ].join('\n');

  playerAnnouncementTemplatesDataScriptCache = {
    signature: signature,
    value: value
  };
  return value;
}

function getPlayerPageAnnouncementsScript() {
  return loadTemplate(playerPageAnnouncementsScriptPath, playerPageAnnouncementsScriptCache || (playerPageAnnouncementsScriptCache = {}));
}

function getPlayerPageScript() {
  return loadTemplate(playerPageScriptPath, playerPageScriptCache || (playerPageScriptCache = {}));
}

function getPlayerRegionScriptPaths() {
  if (!fs.existsSync(playerRegionScriptDir)) {
    return [];
  }

  return fs.readdirSync(playerRegionScriptDir, { withFileTypes: true })
    .filter(function (entry) {
      return entry.isFile() && entry.name.toLowerCase().endsWith('.js');
    })
    .map(function (entry) {
      return path.join(playerRegionScriptDir, entry.name);
    })
    .sort(function (left, right) {
      return left.localeCompare(right);
    });
}

function getPlayerRegionScripts() {
  const sharedPlaceholderUtilsPath = path.join(__dirname, '..', 'web', 'public', 'js', 'shared', 'placeholder-utils.js');
  const sharedQrSvgUtilsPath = path.join(__dirname, '..', 'web', 'public', 'js', 'shared', 'qr-code-svg.js');
  const playerRegionScriptPaths = getPlayerRegionScriptPaths();
  const scriptPaths = [sharedPlaceholderUtilsPath, sharedQrSvgUtilsPath].concat(playerRegionScriptPaths);
  const statSignature = scriptPaths.map(function (filePath) {
    return fs.statSync(filePath).mtimeMs;
  }).join('|');
  if (playerRegionScriptsCache && playerRegionScriptsCache.signature === statSignature) {
    return playerRegionScriptsCache.value;
  }

  const value = scriptPaths.map(function (filePath) {
    return fs.readFileSync(filePath, 'utf8').trim();
  }).join('\n\n');
  playerRegionScriptsCache = {
    signature: statSignature,
    value: value
  };
  return value;
}

function getPlayerOnboardingLandingScript() {
  return loadTemplate(playerOnboardingLandingScriptPath, playerOnboardingLandingScriptCache || (playerOnboardingLandingScriptCache = {}));
}

function getPlayerOnboardingFormScript() {
  return loadTemplate(playerOnboardingFormScriptPath, playerOnboardingFormScriptCache || (playerOnboardingFormScriptCache = {}));
}

module.exports = {
  mediaKind: mediaKind,
  escapeHtml: escapeHtml,
  sanitizeFontFamily: sanitizeFontFamily,
  sanitizeFontSize: sanitizeFontSize,
  sanitizeTextColor: sanitizeTextColor,
  sanitizeRichTextAttributes: sanitizeRichTextAttributes,
  safeJsonForScript: safeJsonForScript,
  parseMaybeJson: parseMaybeJson,
  normalizeContentValue: normalizeContentValue,
  normalizeSlide: normalizeSlide,
  sanitizeRichText: sanitizeRichText,
  renderEditorJsBlock: renderEditorJsBlock,
  renderEditorJsListItem: renderEditorJsListItem,
  renderEditorJsTable: renderEditorJsTable,
  renderEditorJsContent: renderEditorJsContent,
  renderHtmlRegionContent: renderHtmlRegionContent,
  fitCanvasSize: fitCanvasSize,
  loadTemplate: loadTemplate,
  getPlayerPageTemplate: getPlayerPageTemplate,
  getPlayerClientNameScript: getPlayerClientNameScript,
  getPlayerPageOfflineScript: getPlayerPageOfflineScript,
  getPlayerPagePlaylistScript: getPlayerPagePlaylistScript,
  getPlayerPageCommandsScript: getPlayerPageCommandsScript,
  getPlayerPageRenderingScript: getPlayerPageRenderingScript,
  getPlayerPagePlaybackScript: getPlayerPagePlaybackScript,
  getAnnouncementIconsDataScript: getAnnouncementIconsDataScript,
  getPlayerAnnouncementTemplatesDataScript: getPlayerAnnouncementTemplatesDataScript,
  getPlayerAnnouncementTemplatesScript: getPlayerAnnouncementTemplatesScript,
  getPlayerPageAnnouncementsScript: getPlayerPageAnnouncementsScript,
  getPlayerPageScript: getPlayerPageScript,
  getPlayerRegionScripts: getPlayerRegionScripts,
  getPlayerOnboardingLandingScript: getPlayerOnboardingLandingScript,
  getPlayerOnboardingFormScript: getPlayerOnboardingFormScript
};