import logging
import os
import sys
import threading
import time
from collections import deque
from datetime import datetime, timedelta
from typing import Any, Dict, List, Optional, Tuple

import cv2
import numpy as np
import redis

logger = logging.getLogger(__name__)

sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))


class LeavePostAlgorithm:
    STATE_WAITING = "WAITING"
    STATE_ON_DUTY = "ON_DUTY"
    STATE_LEAVING = "LEAVING"
    STATE_OFF_DUTY = "OFF_DUTY"
    STATE_NON_WORK_TIME = "NON_WORK_TIME"

    def __init__(
        self,
        confirm_on_duty_sec: int = 10,
        confirm_leave_sec: int = 10,
        cooldown_sec: int = 300,
        working_hours: Optional[List[Dict]] = None,
        target_class: Optional[str] = "person",
    ):
        self.confirm_on_duty_sec = confirm_on_duty_sec
        self.confirm_leave_sec = confirm_leave_sec
        self.cooldown_sec = cooldown_sec
        self.working_hours = working_hours or []
        self.target_class = target_class

        self.alert_cooldowns: Dict[str, datetime] = {}

        self.state: str = self.STATE_WAITING
        self.state_start_time: Optional[datetime] = None
        self.detection_history: deque = deque()

        self.alarm_sent: bool = False
        self.last_person_time: Optional[datetime] = None

    def _is_in_working_hours(self, dt: Optional[datetime] = None) -> bool:
        if not self.working_hours:
            return True
        dt = dt or datetime.now()
        current_minutes = dt.hour * 60 + dt.minute
        for period in self.working_hours:
            start_minutes = period["start"][0] * 60 + period["start"][1]
            end_minutes = period["end"][0] * 60 + period["end"][1]
            if start_minutes <= current_minutes < end_minutes:
                return True
        return False

    def _check_detection_in_roi(self, detection: Dict, roi_id: str) -> bool:
        matched_rois = detection.get("matched_rois", [])
        for roi in matched_rois:
            if roi.get("roi_id") == roi_id:
                return True
        return False

    def _check_target_class(self, detection: Dict, target_class: Optional[str]) -> bool:
        if not target_class:
            return True
        return detection.get("class") == target_class

    def _get_detection_window(self, current_time: datetime) -> List[bool]:
        detections = []
        while self.detection_history and (current_time - self.detection_history[0][0]).total_seconds() > max(self.confirm_on_duty_sec, self.confirm_leave_sec):
            self.detection_history.popleft()
        for _, has_person in self.detection_history:
            detections.append(has_person)
        return detections

    def _get_latest_bbox(self, tracks: List[Dict], roi_id: str) -> List[float]:
        for det in tracks:
            if self._check_detection_in_roi(det, roi_id):
                return det.get("bbox", [])
        return []

    def process(
        self,
        roi_id: str,
        camera_id: str,
        tracks: List[Dict],
        current_time: Optional[datetime] = None,
    ) -> List[Dict]:
        current_time = current_time or datetime.now()

        in_work = self._is_in_working_hours(current_time)
        alerts = []

        if not in_work:
            self.state = self.STATE_NON_WORK_TIME
            self.detection_history.clear()
            self.alarm_sent = False
            return []

        if self.state == self.STATE_NON_WORK_TIME:
            self.state = self.STATE_WAITING
            self.detection_history.clear()
            self.alarm_sent = False

        roi_has_person = False
        for det in tracks:
            if self._check_detection_in_roi(det, roi_id) and self._check_target_class(det, self.target_class):
                roi_has_person = True
                break

        if self.state == self.STATE_WAITING:
            if roi_has_person:
                self.state = self.STATE_ON_DUTY
                self.state_start_time = current_time
                self.detection_history.clear()
                self.detection_history.append((current_time, True))
            else:
                pass

        elif self.state == self.STATE_ON_DUTY:
            self.detection_history.append((current_time, roi_has_person))
            if not roi_has_person:
                self.state = self.STATE_LEAVING
                self.state_start_time = current_time

        elif self.state == self.STATE_LEAVING:
            self.detection_history.append((current_time, roi_has_person))
            elapsed = (current_time - self.state_start_time).total_seconds()

            if roi_has_person:
                self.state = self.STATE_ON_DUTY
                self.state_start_time = current_time
            elif elapsed >= self.confirm_leave_sec:
                self.state = self.STATE_OFF_DUTY
                self.state_start_time = current_time

        elif self.state == self.STATE_OFF_DUTY:
            elapsed = (current_time - self.state_start_time).total_seconds()

            if roi_has_person:
                self.state = self.STATE_ON_DUTY
                self.state_start_time = current_time
            elif elapsed >= self.confirm_leave_sec:
                cooldown_key = f"{camera_id}_{roi_id}"
                now = datetime.now()
                if cooldown_key not in self.alert_cooldowns or (now - self.alert_cooldowns[cooldown_key]).total_seconds() > self.cooldown_sec:
                    bbox = self._get_latest_bbox(tracks, roi_id)
                    elapsed_minutes = int(elapsed / 60)
                    alerts.append({
                        "track_id": roi_id,
                        "camera_id": camera_id,
                        "bbox": bbox,
                        "duration_minutes": elapsed_minutes,
                        "alert_type": "leave_post",
                        "message": f"离岗 {elapsed_minutes} 分钟",
                    })
                    self.alert_cooldowns[cooldown_key] = now

        return alerts

    def reset(self):
        self.state = self.STATE_WAITING
        self.state_start_time = None
        self.detection_history.clear()
        self.alarm_sent = False
        self.last_person_time = None
        self.alert_cooldowns.clear()

    def get_state(self, roi_id: str) -> Dict[str, Any]:
        return {
            "state": self.state,
            "alarm_sent": self.alarm_sent,
            "last_person_time": self.last_person_time,
        }


class IntrusionAlgorithm:
    def __init__(
        self,
        cooldown_seconds: int = 120,
        confirm_seconds: int = 5,
        target_class: Optional[str] = None,
    ):
        self.cooldown_seconds = cooldown_seconds
        self.confirm_seconds = confirm_seconds
        self.target_class = target_class

        self.last_alert_time: Dict[str, datetime] = {}
        self.alert_triggered: Dict[str, bool] = {}
        self.detection_start: Dict[str, Optional[datetime]] = {}

    def _check_detection_in_roi(self, detection: Dict, roi_id: str) -> bool:
        matched_rois = detection.get("matched_rois", [])
        for roi in matched_rois:
            if roi.get("roi_id") == roi_id:
                return True
        return False

    def _check_target_class(self, detection: Dict, target_class: Optional[str]) -> bool:
        if not target_class:
            return True
        return detection.get("class") == target_class

    def _get_latest_bbox(self, tracks: List[Dict], roi_id: str) -> List[float]:
        for det in tracks:
            if self._check_detection_in_roi(det, roi_id):
                return det.get("bbox", [])
        return []

    def process(
        self,
        roi_id: str,
        camera_id: str,
        tracks: List[Dict],
        current_time: Optional[datetime] = None,
    ) -> List[Dict]:
        current_time = current_time or datetime.now()
        key = f"{camera_id}_{roi_id}"

        roi_has_person = False
        for det in tracks:
            if self._check_detection_in_roi(det, roi_id) and self._check_target_class(det, self.target_class):
                roi_has_person = True
                break

        if not roi_has_person:
            self.detection_start.pop(key, None)
            self.alert_triggered[key] = False
            return []

        if self.alert_triggered.get(key, False):
            elapsed_since_alert = (current_time - self.last_alert_time.get(key, datetime.min)).total_seconds()
            if elapsed_since_alert < self.cooldown_seconds:
                return []
            self.alert_triggered[key] = False

        if self.detection_start.get(key) is None:
            self.detection_start[key] = current_time

        elapsed = (current_time - self.detection_start[key]).total_seconds()
        if elapsed < self.confirm_seconds:
            return []

        bbox = self._get_latest_bbox(tracks, roi_id)
        self.last_alert_time[key] = current_time
        self.alert_triggered[key] = True
        self.detection_start[key] = None

        return [{
            "roi_id": roi_id,
            "camera_id": camera_id,
            "bbox": bbox,
            "alert_type": "intrusion",
            "message": "检测到周界入侵",
        }]

    def reset(self):
        self.last_alert_time.clear()
        self.alert_triggered.clear()
        self.detection_start.clear()


class AlgorithmManager:
    def __init__(self, working_hours: Optional[List[Dict]] = None):
        self.algorithms: Dict[str, Dict[str, Any]] = {}
        self.working_hours = working_hours or []
        self._update_lock = threading.Lock()

        self.default_params = {
            "leave_post": {
                "confirm_on_duty_sec": 10,
                "confirm_leave_sec": 10,
                "cooldown_sec": 300,
                "target_class": "person",
            },
            "intrusion": {
                "cooldown_seconds": 120,
                "confirm_seconds": 5,
                "target_class": None,
            },
        }
        
        self._pubsub = None
        self._pubsub_thread = None
        self._running = False
    
    def start_config_subscription(self):
        """启动配置变更订阅"""
        try:
            from config.settings import get_settings
            settings = get_settings()
            redis_client = redis.Redis(
                host=settings.redis.host,
                port=settings.redis.port,
                db=settings.redis.db,
                password=settings.redis.password,
                decode_responses=True,
            )
            
            self._pubsub = redis_client.pubsub()
            self._pubsub.subscribe("config_update")
            
            self._running = True
            self._pubsub_thread = threading.Thread(
                target=self._config_update_worker,
                name="ConfigUpdateSub",
                daemon=True
            )
            self._pubsub_thread.start()
            logger.info("已启动配置变更订阅")
        except Exception as e:
            logger.error(f"启动配置订阅失败: {e}")
    
    def _config_update_worker(self):
        """配置更新订阅工作线程"""
        try:
            for message in self._pubsub.listen():
                if not self._running:
                    break
                if message["type"] == "message":
                    try:
                        import json
                        data = json.loads(message["data"])
                        if data.get("type") == "roi":
                            roi_ids = data.get("ids", [])
                            if roi_ids:
                                for roi_id in roi_ids:
                                    self.reload_algorithm(roi_id)
                            else:
                                self.reload_all_algorithms()
                    except Exception as e:
                        logger.error(f"处理配置更新消息失败: {e}")
        except Exception as e:
            logger.error(f"配置订阅线程异常: {e}")
    
    def stop_config_subscription(self):
        """停止配置变更订阅"""
        self._running = False
        if self._pubsub:
            self._pubsub.close()
        if self._pubsub_thread and self._pubsub_thread.is_alive():
            self._pubsub_thread.join(timeout=5)
        logger.info("配置订阅已停止")
    
    def load_from_redis(self, roi_id: str) -> bool:
        """从Redis加载单个ROI的算法配置"""
        try:
            from core.config_sync import get_config_sync_manager
            config_manager = get_config_sync_manager()
            roi_config = config_manager.get_roi_from_redis(roi_id)
            
            if not roi_config:
                return False
            
            with self._update_lock:
                algorithm_type = roi_config.get("algorithm_type", "leave_post")
                
                if algorithm_type == "leave_post":
                    params = {
                        "working_hours": roi_config.get("working_hours"),
                        "confirm_on_duty_sec": roi_config.get("confirm_on_duty_sec", 10),
                        "confirm_leave_sec": roi_config.get("confirm_leave_sec", 10),
                        "cooldown_sec": roi_config.get("cooldown_sec", 300),
                        "target_class": roi_config.get("target_class", "person"),
                    }
                    if roi_id in self.algorithms and "leave_post" in self.algorithms[roi_id]:
                        algo = self.algorithms[roi_id]["leave_post"]
                        algo.confirm_on_duty_sec = params["confirm_on_duty_sec"]
                        algo.confirm_leave_sec = params["confirm_leave_sec"]
                        algo.cooldown_sec = params["cooldown_sec"]
                        algo.target_class = params["target_class"]
                        if params["working_hours"]:
                            algo.working_hours = params["working_hours"]
                        logger.info(f"已热更新算法参数: {roi_id}")
                    else:
                        self.register_algorithm(roi_id, "leave_post", params)
                        logger.info(f"已从Redis加载算法: {roi_id}")
                else:
                    params = {}
                    if roi_id in self.algorithms and algorithm_type in self.algorithms[roi_id]:
                        pass
                    else:
                        self.register_algorithm(roi_id, algorithm_type, params)
                        logger.info(f"已从Redis加载算法: {roi_id}")
            
            return True
        except Exception as e:
            logger.error(f"从Redis加载算法配置失败: {e}")
            return False
    
    def reload_algorithm(self, roi_id: str) -> bool:
        """重新加载单个ROI的算法配置"""
        if roi_id not in self.algorithms:
            return self.load_from_redis(roi_id)
        
        self.reset_algorithm(roi_id)
        return self.load_from_redis(roi_id)
    
    def reload_all_algorithms(self) -> int:
        """重新加载所有算法配置"""
        count = 0
        try:
            from core.config_sync import get_config_sync_manager
            config_manager = get_config_sync_manager()
            roi_configs = config_manager.get_all_roi_configs()
            
            for roi_config in roi_configs:
                roi_id = roi_config.get("roi_id")
                if self.reload_algorithm(roi_id):
                    count += 1
            
            logger.info(f"已重新加载 {count} 个算法配置")
            return count
        except Exception as e:
            logger.error(f"重新加载所有算法配置失败: {e}")
            return count
    
    def register_algorithm(
        self,
        roi_id: str,
        algorithm_type: str,
        params: Optional[Dict[str, Any]] = None,
    ):
        if roi_id in self.algorithms and algorithm_type in self.algorithms[roi_id]:
            return

        if roi_id not in self.algorithms:
            self.algorithms[roi_id] = {}

        algo_params = self.default_params.get(algorithm_type, {}).copy()
        if params:
            algo_params.update(params)

        if algorithm_type == "leave_post":
            roi_working_hours = algo_params.get("working_hours") or self.working_hours
            self.algorithms[roi_id]["leave_post"] = LeavePostAlgorithm(
                confirm_on_duty_sec=algo_params.get("confirm_on_duty_sec", 10),
                confirm_leave_sec=algo_params.get("confirm_leave_sec", 10),
                cooldown_sec=algo_params.get("cooldown_sec", 300),
                working_hours=roi_working_hours,
                target_class=algo_params.get("target_class", "person"),
            )
        elif algorithm_type == "intrusion":
            self.algorithms[roi_id]["intrusion"] = IntrusionAlgorithm(
                cooldown_seconds=algo_params.get("cooldown_seconds", 120),
                confirm_seconds=algo_params.get("confirm_seconds", 5),
                target_class=algo_params.get("target_class"),
            )

    def process(
        self,
        roi_id: str,
        camera_id: str,
        algorithm_type: str,
        tracks: List[Dict],
        current_time: Optional[datetime] = None,
    ) -> List[Dict]:
        algo = self.algorithms.get(roi_id, {}).get(algorithm_type)
        if algo is None:
            return []
        return algo.process(roi_id, camera_id, tracks, current_time)

    def update_roi_params(
        self,
        roi_id: str,
        algorithm_type: str,
        params: Dict[str, Any],
    ):
        if roi_id in self.algorithms and algorithm_type in self.algorithms[roi_id]:
            algo = self.algorithms[roi_id][algorithm_type]
            for key, value in params.items():
                if hasattr(algo, key):
                    setattr(algo, key, value)

    def reset_algorithm(self, roi_id: str, algorithm_type: Optional[str] = None):
        if roi_id not in self.algorithms:
            return

        if algorithm_type:
            if algorithm_type in self.algorithms[roi_id]:
                self.algorithms[roi_id][algorithm_type].reset()
        else:
            for algo in self.algorithms[roi_id].values():
                algo.reset()

    def reset_all(self):
        for roi_algorithms in self.algorithms.values():
            for algo in roi_algorithms.values():
                algo.reset()

    def remove_roi(self, roi_id: str):
        if roi_id in self.algorithms:
            self.reset_algorithm(roi_id)
            del self.algorithms[roi_id]

    def get_status(self, roi_id: str) -> Dict[str, Any]:
        status = {}
        if roi_id in self.algorithms:
            for algo_type, algo in self.algorithms[roi_id].items():
                if algo_type == "leave_post":
                    status[algo_type] = {
                        "state": getattr(algo, "state", "WAITING"),
                        "alarm_sent": getattr(algo, "alarm_sent", False),
                    }
                else:
                    status[algo_type] = {
                        "detection_count": len(getattr(algo, "detection_start", {})),
                    }
        return status