from __future__ import annotations

import mimetypes
import os
from http.server import SimpleHTTPRequestHandler, ThreadingHTTPServer
from pathlib import Path
from urllib.parse import unquote, urlparse


ROOT = Path(__file__).resolve().parent
DEFAULT_STATIC_ROOT = ROOT / "dist" if (ROOT / "dist" / "app.html").is_file() else ROOT
STATIC_ROOT = Path(os.environ.get("STATIC_ROOT", DEFAULT_STATIC_ROOT)).resolve()
APP_FILE = STATIC_ROOT / "app.html"
PORT = int(os.environ.get("PORT", "7860"))
APP_ROUTES = {"", "devices", "accelerators", "systems", "models", "compare", "bounds"}


class Handler(SimpleHTTPRequestHandler):
    def do_GET(self) -> None:
        self.serve_app_request(include_body=True)

    def do_HEAD(self) -> None:
        self.serve_app_request(include_body=False)

    def serve_app_request(self, include_body: bool) -> None:
        parsed = urlparse(self.path)
        path = unquote(parsed.path).lstrip("/")
        candidate = (STATIC_ROOT / path).resolve()

        if path.startswith("assets/") and candidate.is_file() and STATIC_ROOT in candidate.parents:
            self.send_file(candidate, include_body=include_body)
            return

        route = path.split("/", 1)[0]
        if route in APP_ROUTES:
            self.send_file(APP_FILE, include_body=include_body)
            return

        if "." in Path(path).name and not candidate.exists():
            self.send_error(404, "File not found")
            return

        self.send_file(APP_FILE, include_body=include_body)

    def send_file(self, path: Path, include_body: bool = True) -> None:
        content_type = mimetypes.guess_type(path.name)[0] or "application/octet-stream"
        data = path.read_bytes()
        self.send_response(200)
        self.send_header("Content-Type", content_type)
        self.send_header("Content-Length", str(len(data)))
        self.send_header("Cache-Control", "no-cache")
        self.end_headers()
        if include_body:
            self.wfile.write(data)


if __name__ == "__main__":
    server = ThreadingHTTPServer(("0.0.0.0", PORT), Handler)
    print(f"Serving Local Frontier on :{PORT}", flush=True)
    server.serve_forever()