"""
Server HTTP untuk Syntax Checker — http://127.0.0.1:8008
Endpoint:
    GET  /api/status  — health-check
    POST /api/syntax  — {"text": "...", "language": "id"}
                        → {"findings": [...], "finding_count": int}
Jalankan:
    python -m src.syntax.syntax_server
    python src/syntax/syntax_server.py --no-ml   # nonaktifkan model (deteksi mati)
"""
from __future__ import annotations
import json
import logging
import sys
from http.server import BaseHTTPRequestHandler, HTTPServer
from pathlib import Path
sys.path.insert(0, str(Path(__file__).parent.parent))
from syntax.syntax_detector import SyntaxChecker
logging.basicConfig(
    level=logging.INFO,
    format="%(asctime)s  %(levelname)-7s  %(message)s",
    datefmt="%H:%M:%S",
)
logger = logging.getLogger(__name__)
_checker: SyntaxChecker | None = None
_use_ml = True

def _get() -> SyntaxChecker:
    global _checker
    if _checker is None:
        _checker = SyntaxChecker(use_ml=_use_ml)
        _checker.load()
    return _checker

class Handler(BaseHTTPRequestHandler):
    def _cors(self):
        self.send_header("Access-Control-Allow-Origin",  "*")
        self.send_header("Access-Control-Allow-Methods", "GET, POST, OPTIONS")
        self.send_header("Access-Control-Allow-Headers", "Content-Type")
    def do_OPTIONS(self):
        self.send_response(204); self._cors(); self.end_headers()
    def _json(self, status: int, body: object):
        payload = json.dumps(body, ensure_ascii=False).encode()
        try:
            self.send_response(status)
            self.send_header("Content-Type",   "application/json; charset=utf-8")
            self.send_header("Content-Length", str(len(payload)))
            self._cors()
            self.end_headers()
            self.wfile.write(payload)
        except (ConnectionAbortedError, BrokenPipeError, ConnectionResetError):
            pass
    def _body(self) -> dict | None:
        n = int(self.headers.get("Content-Length", 0))
        if not n:
            return {}
        try:
            return json.loads(self.rfile.read(n))
        except (json.JSONDecodeError, ValueError):
            return None
    def log_message(self, fmt, *args):
        logger.info("%-6s %s", args[0] if args else "", args[1] if len(args) > 1 else "")
    def do_GET(self):
        if self.path == "/api/status":
            chk = _get()
            self._json(200, {
                "ready":     True,
                "ml_active": chk.ml_active,
            })
        else:
            self._json(404, {"error": "Not found"})
    def do_POST(self):
        if self.path != "/api/syntax":
            self._json(404, {"error": "Not found"}); return
        body = self._body()
        if body is None:
            self._json(400, {"error": "JSON tidak valid."}); return
        text = str(body.get("text", "")).strip()
        if not text:
            self._json(400, {"error": "Field 'text' kosong."}); return
        language = str(body.get("language", "id"))
        findings = _get().check(text, language=language)
        self._json(200, {
            "text":          text,
            "finding_count": len(findings),
            "findings": [
                {
                    "sentence":   f.sentence,
                    "start":      f.start,
                    "end":        f.end,
                    "score":      f.score,
                    "reason":     f.reason,
                    "confidence": f.confidence,
                }
                for f in findings
            ],
        })

if __name__ == "__main__":
    import argparse
    parser = argparse.ArgumentParser()
    parser.add_argument("--port", type=int, default=8008)
    parser.add_argument("--host", default="127.0.0.1")
    parser.add_argument("--no-ml", action="store_true",
                        help="Nonaktifkan model (deteksi mati, server tetap jalan).")
    args = parser.parse_args()
    _use_ml = not args.no_ml
    logger.info("Memuat Syntax Checker (ML: %s)...", "aktif" if _use_ml else "nonaktif")
    chk = _get()
    logger.info("Syntax Checker siap (ML aktif: %s).", chk.ml_active)
    server = HTTPServer((args.host, args.port), Handler)
    logger.info("Syntax server berjalan di http://%s:%d", args.host, args.port)
    try:
        server.serve_forever()
    except KeyboardInterrupt:
        server.server_close()