/** File-extension -> language name used for the Level 0 language histogram. */

const EXTENSION_TO_LANGUAGE: Record<string, string> = {
  ".ts": "TypeScript",
  ".tsx": "TypeScript",
  ".mts": "TypeScript",
  ".cts": "TypeScript",
  ".js": "JavaScript",
  ".jsx": "JavaScript",
  ".mjs": "JavaScript",
  ".cjs": "JavaScript",
  ".py": "Python",
  ".pyi": "Python",
  ".go": "Go",
  ".rs": "Rust",
  ".rb": "Ruby",
  ".java": "Java",
  ".kt": "Kotlin",
  ".kts": "Kotlin",
  ".swift": "Swift",
  ".c": "C",
  ".h": "C",
  ".cpp": "C++",
  ".cc": "C++",
  ".cxx": "C++",
  ".hpp": "C++",
  ".cs": "C#",
  ".fs": "F#",
  ".php": "PHP",
  ".lua": "Lua",
  ".zig": "Zig",
  ".ex": "Elixir",
  ".exs": "Elixir",
  ".erl": "Erlang",
  ".hrl": "Erlang",
  ".clj": "Clojure",
  ".cljs": "Clojure",
  ".scala": "Scala",
  ".hs": "Haskell",
  ".ml": "OCaml",
  ".sh": "Shell",
  ".bash": "Shell",
  ".zsh": "Shell",
  ".fish": "Shell",
  ".ps1": "PowerShell",
  ".sql": "SQL",
  ".html": "HTML",
  ".htm": "HTML",
  ".css": "CSS",
  ".scss": "SCSS",
  ".less": "Less",
  ".md": "Markdown",
  ".mdx": "Markdown",
  ".json": "JSON",
  ".jsonc": "JSON",
  ".yaml": "YAML",
  ".yml": "YAML",
  ".toml": "TOML",
  ".xml": "XML",
  ".vue": "Vue",
  ".svelte": "Svelte",
  ".tf": "Terraform",
  ".proto": "Protobuf",
  ".graphql": "GraphQL",
  ".gql": "GraphQL",
  ".r": "R",
  ".jl": "Julia",
  ".dart": "Dart",
  ".dockerfile": "Dockerfile",
};

/** Look up a language by file extension (with or without leading dot). */
export function languageForExtension(ext: string): string | undefined {
  const key = ext.startsWith(".") ? ext.toLowerCase() : `.${ext.toLowerCase()}`;
  return EXTENSION_TO_LANGUAGE[key];
}