import { StreamLanguage, type StreamParser } from '@codemirror/language'

const CADDY_DIRECTIVES = new Set([
  'reverse_proxy', 'encode', 'file_server', 'handle', 'handle_errors',
  'root', 'header', 'redir', 'rewrite', 'respond', 'route', 'tls',
  'log', 'basicauth', 'request_body', 'try_files', 'php_fastcgi',
  'templates', 'import', 'bind', 'metrics', 'admin', 'auto_https',
])
const CADDY_GLOBAL = new Set(['email', 'storage', 'order', 'servers', 'log'])

const parser: StreamParser<unknown> = {
  token(stream) {
    if (stream.eatSpace()) return null
    if (stream.match(/^#.*/)) return 'comment'
    if (stream.match(/^"(?:[^"\\]|\\.)*"/)) return 'string'
    if (stream.match(/^@[A-Za-z_][\w-]*/)) return 'variableName'
    if (stream.match(/^[{}]/)) return 'brace'
    const word = stream.match(/^[A-Za-z_][\w.-]*/) as RegExpMatchArray | null
    if (word) {
      const w = word[0]
      if (CADDY_DIRECTIVES.has(w)) return 'keyword'
      if (CADDY_GLOBAL.has(w)) return 'typeName'
      return 'variableName'
    }
    stream.next()
    return null
  },
  languageData: { commentTokens: { line: '#' } },
}

export const caddyfileLanguage = StreamLanguage.define(parser)