mime.ts

// MIME Types for Web
const mimeTypes: Record<string, string[]> = {
  // application
  'application/javascript': ['js', 'mjs'],
  'application/wasm': ['wasm'],
  'application/json': ['json', 'map'],
  'application/json5': ['json5'],
  'application/pdf': ['pdf'],
  'application/xml': ['xml', 'xsl'],
  'application/zip': ['zip'],
  // text
  'text/html': ['html', 'htm'],
  'text/markdown': ['md', 'markdown'],
  'text/mdx': ['mdx'],
  'text/typescript': ['ts'],
  'text/tsx': ['tsx'],
  'text/jsx': ['jsx'],
  'text/css': ['css'],
  'text/less': ['less'],
  'text/sass': ['sass', 'scss'],
  'text/stylus': ['stylus', 'styl'],
  'text/csv': ['csv'],
  'text/plain': ['txt', 'text', 'conf', 'ini', 'log', 'yaml'],
  // font
  'font/ttf': ['ttf'],
  'font/otf': ['otf'],
  'font/woff': ['woff'],
  'font/woff2': ['woff2'],
  'font/collection': ['ttc'],
  // image
  'image/jpeg': ['jpg', 'jpeg'],
  'image/png': ['png'],
  'image/apng': ['apng'],
  'image/gif': ['gif'],
  'image/webp': ['webp'],
  'image/avif': ['avif'],
  'image/svg+xml': ['svg', 'svgz'],
  'image/x-icon': ['ico'],
  // audio
  'audio/mp4': ['m4a'],
  'audio/mpeg': ['mp3', 'm3a'],
  'audio/ogg': ['ogg', 'oga'],
  'audio/wav': ['wav'],
  'audio/webm': ['weba'],
  // video
  'video/mp4': ['mp4', 'm4v'],
  'video/ogg': ['ogv'],
  'video/webm': ['webm'],
}

// types map
const typesMap = Object.keys(mimeTypes).reduce((map, contentType) => {
  mimeTypes[contentType].forEach(ext => map.set(ext, contentType))
  return map
}, new Map<string, string>())

/** get content type by file name */
export function getContentType(filename: string): string {
  const ext = filename.split('.').pop()!.toLowerCase()
  return typesMap.get(ext) ?? 'application/octet-stream'
}