#!/usr/bin/env python3
"""Contracts VM server — thin HTTP router. All logic in db/ and services/."""
from http.server import HTTPServer, BaseHTTPRequestHandler
from socketserver import ThreadingMixIn
from urllib.parse import urlparse, parse_qs
import json, re

# ── DB auto-seed ──────────────────────────────────────────────────────────
from db import prompts as db_prompts
from db.connection import DB_CONFIG
db_prompts.seed_defaults()

# ── Services ──────────────────────────────────────────────────────────────
from services.upload import handle_upload
from services.unzip import handle_unzip
from services.process import run_pipeline
from llm_prompt import build_prompt


class ThreadingHTTPServer(ThreadingMixIn, HTTPServer):
    daemon_threads = True


class Handler(BaseHTTPRequestHandler):
    def do_OPTIONS(self):
        self.send_response(200)
        self._send_cors()
        self.send_header("Access-Control-Allow-Methods", "GET, POST, OPTIONS")
        self.send_header("Access-Control-Allow-Headers", "Content-Type")
        self.end_headers()

    def do_GET(self):
        parsed = urlparse(self.path)
        if parsed.path == "/process-v2":
            self._handle_process_v2(parsed)
        elif parsed.path == "/health":
            self._json({"ok": True, "db": DB_CONFIG["dbname"]})
        else:
            self.send_error(404)

    def do_POST(self):
        if self.path == "/upload":
            self._handle_upload()
        elif self.path == "/unzip-upload":
            self._handle_unzip()
        elif self.path == "/llm-ops":
            self._handle_llm_ops()
        else:
            self.send_error(404)

    # ── /process-v2 (SSE) ─────────────────────────────────────────────────

    def _handle_process_v2(self, parsed):
        params = parse_qs(parsed.query)
        cid = params.get("contract_id", [None])[0]
        if not cid:
            self.send_error(400, "contract_id required")
            return
        if not re.fullmatch(r'[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}', cid, re.I):
            self.send_error(400, "invalid contract_id format")
            return

        self.send_response(200)
        self.send_header("Content-Type", "text/event-stream; charset=utf-8")
        self.send_header("Cache-Control", "no-cache")
        self.send_header("Connection", "keep-alive")
        self.end_headers()
        self.wfile.write(b": ok\n\n")
        self.wfile.flush()

        order_ids = params.get("order", [None])[0] or ""

        try:
            run_pipeline(cid, order_ids, self._sse, build_prompt)
        except Exception as e:
            self._sse({"type": "error", "message": str(e)})

    def _sse(self, data):
        self.wfile.write(f"data: {json.dumps(data, ensure_ascii=False)}\n\n".encode())
        self.wfile.flush()

    # ── /upload ───────────────────────────────────────────────────────────

    def _handle_upload(self):
        try:
            content_type = self.headers.get("Content-Type", "")
            content_length = int(self.headers.get("Content-Length", 0))
            result = handle_upload(self.rfile, content_type, content_length)
            self._json(result)
        except Exception as e:
            self._json({"ok": False, "error": str(e)}, 500)

    # ── /unzip-upload ─────────────────────────────────────────────────────

    def _handle_unzip(self):
        try:
            content_length = int(self.headers.get("Content-Length", 0))
            result = handle_unzip(self.rfile, content_length)
            self._json(result)
        except Exception as e:
            self._json({"ok": False, "error": str(e)}, 500)

    # ── /llm-ops (debug) ──────────────────────────────────────────────────

    def _handle_llm_ops(self):
        from services.llm import call_llm
        length = int(self.headers.get("Content-Length", 0))
        body = json.loads(self.rfile.read(length))
        try:
            result, prompt_id = call_llm(
                body.get("current_spec", []),
                body.get("doc_text", ""),
                build_prompt,
            )
            self._json(result)
        except Exception as e:
            self._json({"error": str(e)}, 502)

    # ── Helpers ───────────────────────────────────────────────────────────

    def _json(self, data, status=200):
        self.send_response(status)
        self._send_cors()
        self.send_header("Content-Type", "application/json; charset=utf-8")
        self.end_headers()
        self.wfile.write(json.dumps(data, ensure_ascii=False).encode())

    def _send_cors(self):
        self.send_header("Access-Control-Allow-Origin", "*")

    def log_message(self, format, *args):
        pass


if __name__ == "__main__":
    import os
    port = int(os.environ.get("PORT", "8766"))
    server = ThreadingHTTPServer(("0.0.0.0", port), Handler)
    print(f"Contracts VM server on :{port}, db={DB_CONFIG['dbname']}")
    try:
        server.serve_forever()
    except KeyboardInterrupt:
        server.shutdown()