/**
 * Lightweight MIME type utilities
 *
 * Replaces the heavy mime-types package (146KB) with a small lookup
 * for common web file types.
 */

// Extension to MIME type mapping
const extToMime: Record<string, string> = {
  // Images
  jpg: 'image/jpeg',
  jpeg: 'image/jpeg',
  png: 'image/png',
  gif: 'image/gif',
  webp: 'image/webp',
  svg: 'image/svg+xml',
  ico: 'image/x-icon',
  bmp: 'image/bmp',
  tiff: 'image/tiff',
  tif: 'image/tiff',
  avif: 'image/avif',

  // Documents
  pdf: 'application/pdf',
  doc: 'application/msword',
  docx: 'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
  xls: 'application/vnd.ms-excel',
  xlsx: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
  ppt: 'application/vnd.ms-powerpoint',
  pptx: 'application/vnd.openxmlformats-officedocument.presentationml.presentation',
  odt: 'application/vnd.oasis.opendocument.text',
  ods: 'application/vnd.oasis.opendocument.spreadsheet',

  // Text
  txt: 'text/plain',
  html: 'text/html',
  htm: 'text/html',
  css: 'text/css',
  csv: 'text/csv',
  xml: 'text/xml',
  md: 'text/markdown',
  markdown: 'text/markdown',

  // Code
  js: 'text/javascript',
  mjs: 'text/javascript',
  ts: 'text/typescript',
  json: 'application/json',
  jsonld: 'application/ld+json',

  // RDF
  ttl: 'text/turtle',
  n3: 'text/n3',
  nt: 'application/n-triples',
  nq: 'application/n-quads',
  rdf: 'application/rdf+xml',
  trig: 'application/trig',

  // Audio
  mp3: 'audio/mpeg',
  wav: 'audio/wav',
  ogg: 'audio/ogg',
  oga: 'audio/ogg',
  m4a: 'audio/mp4',
  flac: 'audio/flac',
  aac: 'audio/aac',
  weba: 'audio/webm',

  // Video
  mp4: 'video/mp4',
  m4v: 'video/mp4',
  webm: 'video/webm',
  ogv: 'video/ogg',
  avi: 'video/x-msvideo',
  mov: 'video/quicktime',
  mkv: 'video/x-matroska',

  // Archives
  zip: 'application/zip',
  gz: 'application/gzip',
  tar: 'application/x-tar',
  rar: 'application/vnd.rar',
  '7z': 'application/x-7z-compressed',

  // Fonts
  woff: 'font/woff',
  woff2: 'font/woff2',
  ttf: 'font/ttf',
  otf: 'font/otf',
  eot: 'application/vnd.ms-fontobject',

  // Other
  wasm: 'application/wasm',
  bin: 'application/octet-stream',
}

// MIME type to preferred extension mapping
const mimeToExt: Record<string, string> = {}
for (const [ext, mime] of Object.entries(extToMime)) {
  // Only set if not already set (first extension wins as preferred)
  if (!mimeToExt[mime]) {
    mimeToExt[mime] = ext
  }
}

/**
 * Get MIME type from filename
 * @param filename - The filename or path
 * @returns The MIME type or false if not found
 */
export function lookup (filename: string): string | false {
  const ext = filename.split('.').pop()?.toLowerCase()
  if (!ext) return false
  return extToMime[ext] || false
}

/**
 * Get preferred extension for a MIME type
 * @param mimeType - The MIME type
 * @returns The extension (without dot) or false if not found
 */
export function extension (mimeType: string): string | false {
  // Handle mime types with parameters (e.g., "text/plain; charset=utf-8")
  const baseMime = mimeType.split(';')[0].trim().toLowerCase()
  return mimeToExt[baseMime] || false
}

export default { lookup, extension }