"""
HY Memory - Lightweight HTTP Server

Zero-dependency HTTP server (stdlib only) that wraps HyMemoryClient
for local use by the OpenClaw plugin.

Usage:
    python -m hy_memory.server                    # default port 19527
    python -m hy_memory.server --port 19528
    HY_MEMORY_SERVER_PORT=19528 python -m hy_memory.server

API Endpoints:
    POST /api/v1/add          — Write memory
    POST /api/v1/search       — Search memories
    POST /api/v1/user_profile — Get assembled user profile
    GET  /api/v1/memories/:id — Get single memory
    POST /api/v1/list         — List memories
    PUT  /api/v1/memories/:id — Update memory
    DELETE /api/v1/memories/:id — Delete memory
    POST /api/v1/delete_all   — Delete all user memories
    GET  /healthz             — Health check (static, process alive)
    GET  /health              — Liveness probe (pings internal event loop; 503 if loop blocked)
    GET  /info                — Server info
"""

import asyncio
import json
import logging
import os
import re
import signal
import threading
from datetime import datetime
from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
from typing import Any, Dict, Optional

logger = logging.getLogger("hy_memory.server")

# Lazy-init global client
_client = None
_client_lock = None


def _get_client():
    """Lazy-initialize the HyMemoryClient singleton."""
    global _client
    if _client is not None:
        return _client
    from .client import HyMemoryClient
    from .config import MemoryConfig

    logger.info("[server] Initializing HyMemoryClient...")

    config = MemoryConfig.from_env()

    # ---- 胶水: thinking mode + temperature 强制 ----
    # 当环境变量 HY_MEMORY_THINKING_MODE 设置时，对支持 thinking 的模型注入控制参数
    thinking_mode = os.getenv("HY_MEMORY_THINKING_MODE")
    if thinking_mode:
        _llm_model = (config.llm.model or "").lower()
        # 需要 extra_body.thinking 控制的模型
        _needs_thinking_body = (
            "kimi" in _llm_model
            or "deepseek" in _llm_model
            or "qwen" in _llm_model
            or "hy3" in _llm_model
            or "hunyuan" in _llm_model
        )
        if _needs_thinking_body:
            extra = config.llm.extra_body or {}
            extra["thinking"] = {"type": thinking_mode}
            config.llm.extra_body = extra
            # kimi/deepseek 有温度硬约束
            if "kimi" in _llm_model or "deepseek" in _llm_model:
                required_temp = 0.6 if thinking_mode == "disabled" else 1.0
                config.llm.temperature = required_temp
            logger.info(f"[server] thinking adapter: model={config.llm.model}, thinking={thinking_mode}")

    _client = HyMemoryClient(config=config)
    logger.info("[server] HyMemoryClient ready")
    return _client


def _json_response(handler: BaseHTTPRequestHandler, status: int, data: Any):
    """Send a JSON response."""
    body = json.dumps(data, ensure_ascii=False, default=str).encode("utf-8")
    handler.send_response(status)
    handler.send_header("Content-Type", "application/json; charset=utf-8")
    handler.send_header("Content-Length", str(len(body)))
    handler.send_header("Access-Control-Allow-Origin", "*")
    handler.end_headers()
    handler.wfile.write(body)


def _read_json_body(handler: BaseHTTPRequestHandler) -> Optional[Dict]:
    """Read and parse JSON request body."""
    content_length = int(handler.headers.get("Content-Length", 0))
    if content_length == 0:
        return {}
    raw = handler.rfile.read(content_length)
    try:
        return json.loads(raw.decode("utf-8"))
    except Exception:
        return None


class MemoryHTTPHandler(BaseHTTPRequestHandler):
    """HTTP request handler for HY Memory API."""

    # Suppress default access log
    def log_message(self, format, *args):
        logger.debug(f"[http] {args[0] if args else ''}")

    def do_OPTIONS(self):
        """Handle CORS preflight."""
        self.send_response(204)
        self.send_header("Access-Control-Allow-Origin", "*")
        self.send_header("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS")
        self.send_header("Access-Control-Allow-Headers", "Content-Type, Authorization")
        self.send_header("Access-Control-Max-Age", "86400")
        self.end_headers()

    def do_GET(self):
        path = self.path.split("?")[0].rstrip("/")
        try:
            if path == "/healthz":
                _json_response(self, 200, {"status": "ok"})
                return

            if path == "/health":
                self._handle_health_liveness()
                return

            if path == "/api/v1/status":
                self._handle_healthz()
                return

            if path == "/info":
                from . import __version__
                _json_response(self, 200, {
                    "name": "hy-memory-server",
                    "version": __version__,
                    "status": "running",
                })
                return

            # GET /api/v1/metrics?minutes=5
            if path == "/api/v1/metrics":
                minutes = 5
                if "?" in self.path:
                    from urllib.parse import parse_qs, urlparse
                    qs = parse_qs(urlparse(self.path).query)
                    minutes = int(qs.get("minutes", ["5"])[0])
                client = _get_client()
                result = client.get_metrics(minutes=minutes)
                _json_response(self, 200, result)
                return

            # GET /api/v1/memories/:id
            m = re.match(r"^/api/v1/memories/([^/]+)$", path)
            if m:
                memory_id = m.group(1)
                client = _get_client()
                result = client.get(memory_id)
                if result is None:
                    _json_response(self, 404, {"error": "not_found", "memory_id": memory_id})
                else:
                    _json_response(self, 200, result)
                return

            _json_response(self, 404, {"error": "not_found", "path": path})

        except Exception as e:
            logger.error(f"[server] GET {path} error: {e}", exc_info=True)
            _json_response(self, 500, {"error": str(e)})

    def do_POST(self):
        path = self.path.rstrip("/")
        body = _read_json_body(self)
        if body is None:
            _json_response(self, 400, {"error": "invalid JSON body"})
            return

        try:
            if path == "/api/v1/add":
                self._handle_add(body)
                return

            if path == "/api/v1/add_extracted":
                self._handle_add_extracted(body)
                return

            if path == "/api/v1/search":
                self._handle_search(body)
                return

            if path == "/api/v1/user_profile":
                self._handle_user_profile(body)
                return

            if path == "/api/v1/list":
                self._handle_list(body)
                return

            if path == "/api/v1/delete_all":
                self._handle_delete_all(body)
                return

            _json_response(self, 404, {"error": "not_found", "path": path})

        except Exception as e:
            logger.error(f"[server] POST {path} error: {e}", exc_info=True)
            _json_response(self, 500, {"error": str(e)})

    def do_PUT(self):
        path = self.path.rstrip("/")
        body = _read_json_body(self)
        if body is None:
            _json_response(self, 400, {"error": "invalid JSON body"})
            return

        try:
            m = re.match(r"^/api/v1/memories/([^/]+)$", path)
            if m:
                memory_id = m.group(1)
                content = body.get("content", "")
                if not content:
                    _json_response(self, 400, {"error": "content is required"})
                    return
                client = _get_client()
                result = client.update(memory_id, content)
                _json_response(self, 200, result)
                return

            _json_response(self, 404, {"error": "not_found", "path": path})

        except Exception as e:
            logger.error(f"[server] PUT {path} error: {e}", exc_info=True)
            _json_response(self, 500, {"error": str(e)})

    def do_DELETE(self):
        path = self.path.rstrip("/")
        try:
            m = re.match(r"^/api/v1/memories/([^/]+)$", path)
            if m:
                memory_id = m.group(1)
                client = _get_client()
                result = client.delete(memory_id)
                _json_response(self, 200, result)
                return

            _json_response(self, 404, {"error": "not_found", "path": path})

        except Exception as e:
            logger.error(f"[server] DELETE {path} error: {e}", exc_info=True)
            _json_response(self, 500, {"error": str(e)})

    # ================================================================
    # Route handlers
    # ================================================================

    def _handle_health_liveness(self):
        """轻量存活探针：探测内部 event loop（_LoopThread）是否还活着。

        与 /api/v1/status（深度检查 VDB/embed/LLM，且自己临时开新 loop）不同，本
        endpoint 专门探测真正承载所有业务协程的那个 _LoopThread loop 是否被阻塞/死锁。

        做法：往 _loop_thread 的 loop 投一个几乎零成本的 ping 协程，带短超时等待结果。
          - loop 正常调度 → 快速返回 200 {"status":"alive"}
          - loop 卡死（如被同步阻塞）→ 超时 → 503 {"status":"loop_blocked"}
        绝不调用任何业务方法、绝不碰 VDB/LLM，也不给任何业务请求加超时。这样外部探活
        能明确区分「进程活着」与「loop 活着」，据此重启 sidecar，而不会误伤正常长写入。
        """

        try:
            client = _get_client()
        except Exception as e:
            _json_response(self, 503, {"status": "error", "error": f"client init failed: {e}"})
            return

        loop_thread = getattr(client, "_loop_thread", None)
        loop = getattr(loop_thread, "_loop", None)
        if loop is None:
            _json_response(self, 503, {"status": "error", "error": "no internal loop"})
            return

        if not loop.is_running():
            _json_response(self, 503, {"status": "loop_stopped"})
            return

        async def _ping():
            return True

        try:
            fut = asyncio.run_coroutine_threadsafe(_ping(), loop)
            # 短超时：loop 正常时 ping 是微秒级；卡死则超时判定为不可用
            fut.result(timeout=2.0)
            _json_response(self, 200, {"status": "alive"})
        except Exception:
            # 超时或调度失败 → loop 被阻塞/死锁
            try:
                fut.cancel()
            except Exception:
                pass
            _json_response(self, 503, {"status": "loop_blocked"})

    def _handle_healthz(self):
        """Deep health check: verify VDB, embed, and LLM connectivity."""

        checks = {"status": "ok", "vdb": "ok", "embed": "ok", "llm": "ok"}
        has_error = False

        try:
            client = _get_client()
        except Exception as e:
            _json_response(self, 503, {"status": "error", "error": f"client init failed: {e}"})
            return

        # 1. VDB check — get stats
        try:
            loop = asyncio.new_event_loop()
            stats = loop.run_until_complete(client._vector_store.get_stats())
            loop.close()
            checks["vdb"] = "ok"
            checks["vdb_provider"] = client._config.vector_store.provider
            checks["vdb_collection"] = client._vector_store._collection_name
            checks["vdb_points"] = stats.get("points_count", stats.get("vectors_count", "?"))
        except Exception as e:
            checks["vdb"] = f"error: {e}"
            checks["vdb_provider"] = client._config.vector_store.provider
            has_error = True

        # 2. Embed check — embed a single test string
        try:
            loop = asyncio.new_event_loop()
            vectors = loop.run_until_complete(client._embed_service.embed("health check"))
            loop.close()
            if vectors and len(vectors) > 0:
                checks["embed"] = "ok"
                checks["embed_dims"] = len(vectors)
            else:
                checks["embed"] = "error: empty response"
                has_error = True
        except Exception as e:
            checks["embed"] = f"error: {e}"
            has_error = True

        # 3. LLM check — simple completion
        try:
            from openai import OpenAI
            llm_cfg = client._config.llm
            llm_client = OpenAI(
                api_key=llm_cfg.api_key,
                base_url=llm_cfg.base_url or None,
                timeout=10,
            )
            resp = llm_client.chat.completions.create(
                model=llm_cfg.model,
                messages=[{"role": "user", "content": "hi"}],
                max_tokens=1,
            )
            if resp.choices:
                checks["llm"] = "ok"
            else:
                checks["llm"] = "error: no choices"
                has_error = True
        except Exception as e:
            checks["llm"] = f"error: {e}"
            has_error = True

        checks["status"] = "degraded" if has_error else "ok"
        status_code = 200 if not has_error else 503
        _json_response(self, status_code, checks)

    def _handle_add(self, body: Dict):
        """POST /api/v1/add"""
        data = body.get("data")
        if data is None:
            # Support both "data" (str or messages list) and "messages" key
            messages = body.get("messages")
            text = body.get("text", "")
            if messages:
                data = messages
            elif text:
                data = text
            else:
                _json_response(self, 400, {"error": "data, text, or messages is required"})
                return

        client = _get_client()
        kwargs = {}
        for key in ("user_id", "agent_id", "session_id", "metadata"):
            if key in body:
                kwargs[key] = body[key]

        # memory_at
        if body.get("memory_at"):
            try:
                kwargs["memory_at"] = datetime.fromisoformat(body["memory_at"])
            except Exception:
                pass

        result = client.add(data, **kwargs)
        _json_response(self, 200, result)

    def _handle_add_extracted(self, body: Dict):
        """POST /api/v1/add_extracted — 写入已抽取好的记忆（跳过 extract，直接 reconcile）"""
        # 接受 contents (str 或 list) / content / text
        contents = body.get("contents")
        if contents is None:
            single = body.get("content") or body.get("text")
            if single:
                contents = single
        if not contents:
            _json_response(self, 400, {"error": "contents, content, or text is required"})
            return

        client = _get_client()
        kwargs = {}
        for key in ("user_id", "agent_id", "session_id", "metadata"):
            if key in body:
                kwargs[key] = body[key]
        if body.get("memory_at"):
            try:
                kwargs["memory_at"] = datetime.fromisoformat(body["memory_at"])
            except Exception:
                pass

        result = client.add_extracted(contents, **kwargs)
        _json_response(self, 200, result)

    def _handle_search(self, body: Dict):
        """POST /api/v1/search"""
        query = body.get("query", "")
        if not query:
            _json_response(self, 400, {"error": "query is required"})
            return

        client = _get_client()
        kwargs = {}

        # user_ids: required by SDK, but for openclaw convenience
        # accept both user_ids (list) and user_id (str)
        user_ids = body.get("user_ids")
        if not user_ids:
            user_id = body.get("user_id", "")
            if user_id:
                user_ids = [user_id]
        if not user_ids:
            _json_response(self, 400, {"error": "user_id or user_ids is required"})
            return
        kwargs["user_ids"] = user_ids

        for key in ("agent_ids", "session_ids"):
            if key in body:
                kwargs[key] = body[key]

        for key in ("limit", "min_score", "schema_min_score", "schema_limit", "reader"):
            if key in body:
                kwargs[key] = body[key]

        result = client.search(query, **kwargs)
        _json_response(self, 200, result)

    def _handle_user_profile(self, body: Dict):
        """POST /api/v1/user_profile"""
        user_id = str(body.get("user_id") or "").strip()
        if not user_id:
            _json_response(self, 400, {"error": "user_id is required"})
            return
        client = _get_client()
        result = client.get_user_profile(
            user_id=user_id,
        )
        _json_response(self, 200, result)

    def _handle_list(self, body: Dict):
        """POST /api/v1/list"""
        client = _get_client()
        kwargs = {}
        for key in ("user_id", "agent_id", "limit", "offset", "order"):
            if key in body:
                kwargs[key] = body[key]
        result = client.list_memories(**kwargs)
        _json_response(self, 200, result)

    def _handle_delete_all(self, body: Dict):
        """POST /api/v1/delete_all"""
        client = _get_client()
        kwargs = {}
        for key in ("user_id", "agent_ids", "session_ids"):
            if key in body:
                kwargs[key] = body[key]
        result = client.delete_all(**kwargs)
        _json_response(self, 200, result)


def _request_shutdown(server: ThreadingHTTPServer) -> None:
    """Ask ``serve_forever`` to stop without blocking the calling thread.

    ``BaseServer.shutdown()`` waits for the ``serve_forever`` loop to exit. A
    signal handler runs on the very thread executing that loop, so calling it
    there deadlocks forever. Hand the call to a helper thread instead.
    """
    threading.Thread(target=server.shutdown, daemon=True).start()


def run_server(port: int = 19527, host: str = "127.0.0.1"):
    """Start the HTTP server (blocking)."""
    # Configure logging — basicConfig for root; hy_memory level set after client init
    log_level = getattr(logging, os.getenv("MEMORY_LOG_LEVEL", "INFO").upper(), logging.INFO)
    logging.basicConfig(
        level=logging.WARNING,
        format="%(asctime)s [%(levelname)s] %(name)s: %(message)s",
    )

    # Pre-initialize client to fail fast (this calls setup_logging internally)
    logger.info(f"[server] Starting HY Memory Server on {host}:{port}")
    _get_client()

    # After setup_logging has run, force correct levels
    hy_logger = logging.getLogger("hy_memory")
    hy_logger.setLevel(log_level)
    for h in hy_logger.handlers:
        h.setLevel(log_level)
    # Suppress noisy third-party debug logs (must be after setup_logging)
    for noisy in ("openai", "httpx", "httpcore"):
        logging.getLogger(noisy).setLevel(logging.WARNING)

    # Use ThreadingHTTPServer so /healthz is never blocked by long-running requests
    server = ThreadingHTTPServer((host, port), MemoryHTTPHandler)
    server.daemon_threads = True  # Threads die with main process
    logger.info(f"[server] Listening on http://{host}:{port}")
    logger.info(f"[server] Health check: http://{host}:{port}/healthz")

    # Graceful shutdown. The signal handler only asks a helper thread to stop
    # the loop; cleanup runs after serve_forever() returns so it cannot race
    # the request threads or deadlock the serving thread.
    def _shutdown(signum, frame):
        logger.info("[server] Shutting down...")
        _request_shutdown(server)

    signal.signal(signal.SIGINT, _shutdown)
    signal.signal(signal.SIGTERM, _shutdown)

    try:
        server.serve_forever()
    except KeyboardInterrupt:
        _shutdown(None, None)
    finally:
        server.server_close()
        if _client is not None:
            _client.close()


def main():
    """Entry point for `python -m hy_memory.server`."""
    import argparse
    parser = argparse.ArgumentParser(description="HY Memory HTTP Server")
    parser.add_argument(
        "--port", type=int,
        default=int(os.getenv("HY_MEMORY_SERVER_PORT", "19527")),
        help="Port to listen on (default: 19527)",
    )
    parser.add_argument(
        "--host", type=str,
        default=os.getenv("HY_MEMORY_SERVER_HOST", "127.0.0.1"),
        help="Host to bind to (default: 127.0.0.1)",
    )
    args = parser.parse_args()
    run_server(port=args.port, host=args.host)


if __name__ == "__main__":
    main()