"""
球机(PTZ)控制模块
负责PTZ控制、精确定位和视频流获取
"""

import os
# 必须在导入cv2之前设置，防止FFmpeg多线程解码崩溃
os.environ['OPENCV_FFMPEG_CAPTURE_OPTIONS'] = 'threads;1'

import math
import time
import threading
import queue
from typing import Optional, Tuple, Dict
from dataclasses import dataclass

import cv2
import numpy as np

from config import PTZ_CAMERA, PTZ_CONFIG
from dahua_sdk import DahuaSDK, PTZCommand
from video_lock import safe_read, safe_is_opened


@dataclass
class PTZPosition:
    """PTZ位置信息"""
    pan: float      # 水平角度 (0-360度)
    tilt: float     # 垂直角度 (-90到90度)
    zoom: float     # 变倍 (1-最大倍数)


class PTZCamera:
    """球机控制类"""
    
    def __init__(self, sdk: DahuaSDK, camera_config: Dict = None):
        """
        初始化球机
        Args:
            sdk: 大华SDK实例
            camera_config: 摄像头配置
        """
        self.sdk = sdk
        self.config = camera_config or PTZ_CAMERA
        self.ptz_config = PTZ_CONFIG
        
        self.login_handle = None
        self.connected = False
        
        # 当前位置
        self.current_position = PTZPosition(pan=0, tilt=0, zoom=1)
        self.position_lock = threading.Lock()
        
        # 视频流 (用于校准时抓拍球机画面)
        self.rtsp_cap = None
        self.current_frame = None
        self.frame_lock = threading.Lock()
        self.stream_thread = None
        self.running_stream = False
        self._camera_id = 'ptz'  # 用于per-camera锁
    
    def connect(self) -> bool:
        """
        连接球机
        Returns:
            是否成功
        """
        print(f"[PTZCamera] 正在连接球机: IP={self.config['ip']}:{self.config['port']}, 通道={self.config['channel']}")
        
        login_handle, error = self.sdk.login(
            self.config['ip'],
            self.config['port'],
            self.config['username'],
            self.config['password']
        )
        
        if login_handle is None:
            print(f"[PTZCamera] 连接球机失败: IP={self.config['ip']}, 错误码={error}")
            print(f"[PTZCamera] 请检查: 1)IP地址是否正确 2)网络是否连通 3)用户名密码是否正确")
            return False
        
        self.login_handle = login_handle
        self.connected = True
        print(f"[PTZCamera] 成功连接球机: {self.config['ip']}, handle={login_handle}")
        print(f"[PTZCamera] 配置: 通道={self.config['channel']}, 默认变倍={self.ptz_config['default_zoom']}")
        return True
    
    def disconnect(self):
        """断开连接"""
        self.stop_stream()
        if self.login_handle:
            self.sdk.logout(self.login_handle)
            self.login_handle = None
        self.connected = False
    
    def start_stream_rtsp(self, rtsp_url: str = None) -> bool:
        """启动RTSP视频流 (用于校准时获取球机画面)"""
        if rtsp_url is None:
            rtsp_url = self.config.get('rtsp_url') or \
                f"rtsp://{self.config['username']}:{self.config['password']}@{self.config['ip']}:{self.config.get('rtsp_port', 554)}/cam/realmonitor?channel=1&subtype=1"
        
        try:
            # 先尝试FFmpeg后端
            self.rtsp_cap = cv2.VideoCapture(rtsp_url, cv2.CAP_FFMPEG)
            if not self.rtsp_cap.isOpened():
                # FFmpeg失败，尝试GStreamer后端（ARM64上更稳定）
                print(f"[PTZCamera] FFmpeg后端无法打开RTSP流，尝试GStreamer后端...")
                try:
                    gst_cap = cv2.VideoCapture(rtsp_url, cv2.CAP_GSTREAMER)
                    if gst_cap.isOpened():
                        self.rtsp_cap = gst_cap
                        print(f"[PTZCamera] 使用GStreamer后端打开RTSP流成功")
                    else:
                        print(f"[PTZCamera] 无法打开RTSP流: {rtsp_url}")
                        return False
                except Exception as ge:
                    print(f"[PTZCamera] GStreamer后端也不可用: {ge}")
                    return False
            
            self.rtsp_cap.set(cv2.CAP_PROP_BUFFERSIZE, 1)
            
            self.running_stream = True
            self.stream_thread = threading.Thread(target=self._stream_worker, daemon=True)
            self.stream_thread.start()
            print(f"[PTZCamera] RTSP视频流已启动")
            return True
        except Exception as e:
            print(f"[PTZCamera] RTSP流启动失败: {e}")
            return False
    
    def _stream_worker(self):
        """视频流工作线程"""
        import signal
        if hasattr(signal, 'pthread_sigmask'):
            try:
                signal.pthread_sigmask(signal.SIG_BLOCK, {signal.SIGINT})
            except (AttributeError, OSError):
                pass
        
        max_consecutive_errors = 50
        error_count = 0
        
        while self.running_stream:
            try:
                if self.rtsp_cap is None or not safe_is_opened(self.rtsp_cap, self._camera_id):
                    time.sleep(0.1)
                    continue
                
                ret, frame = safe_read(self.rtsp_cap, self._camera_id)
                if not ret or frame is None:
                    error_count += 1
                    if error_count > max_consecutive_errors:
                        print("[PTZCamera] RTSP流连续读取失败，尝试重连...")
                        self._reconnect_rtsp()
                        error_count = 0
                    time.sleep(0.01)
                    continue
                
                error_count = 0
                
                with self.frame_lock:
                    self.current_frame = frame.copy()
                
                time.sleep(0.001)
            except Exception as e:
                err_str = str(e)
                if 'async_lock' in err_str or 'Assertion' in err_str:
                    print(f"[PTZCamera] FFmpeg内部错误，3秒后重建连接: {e}")
                    time.sleep(3)
                    self._reconnect_rtsp()
                else:
                    print(f"[PTZCamera] 视频流错误: {e}")
                    time.sleep(0.5)
    
    def _reconnect_rtsp(self):
        rtsp_url = self.config.get('rtsp_url') or \
            f"rtsp://{self.config['username']}:{self.config['password']}@{self.config['ip']}:{self.config.get('rtsp_port', 554)}/cam/realmonitor?channel=1&subtype=1"
        
        if self.rtsp_cap is not None:
            try:
                self.rtsp_cap.release()
            except Exception:
                pass
            self.rtsp_cap = None
        
        time.sleep(1)
        
        try:
            self.rtsp_cap = cv2.VideoCapture(rtsp_url, cv2.CAP_FFMPEG)
            if safe_is_opened(self.rtsp_cap, self._camera_id):
                self.rtsp_cap.set(cv2.CAP_PROP_BUFFERSIZE, 1)
                print("[PTZCamera] RTSP流重连成功")
            else:
                print("[PTZCamera] RTSP流重连失败")
                self.rtsp_cap = None
        except Exception as e:
            print(f"[PTZCamera] RTSP流重连异常: {e}")
            self.rtsp_cap = None
    
    def get_frame(self) -> Optional[np.ndarray]:
        """获取球机当前帧"""
        with self.frame_lock:
            return self.current_frame.copy() if self.current_frame is not None else None
    
    def stop_stream(self):
        """停止视频流"""
        self.running_stream = False
        if self.stream_thread:
            self.stream_thread.join(timeout=2)
            self.stream_thread = None
        if self.rtsp_cap:
            self.rtsp_cap.release()
            self.rtsp_cap = None
    
    def ptz_control(self, command: int, param1: int = 0, param2: int = 0, 
                    param3: int = 0, stop: bool = False) -> bool:
        """
        PTZ控制
        Args:
            command: 控制命令
            param1-3: 参数
            stop: 是否停止
        Returns:
            是否成功
        """
        if not self.connected:
            print(f"[PTZCamera] PTZ控制失败: 未连接球机")
            return False
        
        if self.login_handle is None or self.login_handle <= 0:
            print(f"[PTZCamera] PTZ控制失败: 登录句柄无效 (handle={self.login_handle})")
            return False
        
        return self.sdk.ptz_control(
            self.login_handle,
            self.config['channel'],
            command, param1, param2, param3, stop
        )
    
    def move_up(self, speed: int = 4, stop: bool = False) -> bool:
        """向上移动"""
        return self.ptz_control(PTZCommand.UP, 0, speed, 0, stop)
    
    def move_down(self, speed: int = 4, stop: bool = False) -> bool:
        """向下移动"""
        return self.ptz_control(PTZCommand.DOWN, 0, speed, 0, stop)
    
    def move_left(self, speed: int = 4, stop: bool = False) -> bool:
        """向左移动"""
        return self.ptz_control(PTZCommand.LEFT, 0, speed, 0, stop)
    
    def move_right(self, speed: int = 4, stop: bool = False) -> bool:
        """向右移动"""
        return self.ptz_control(PTZCommand.RIGHT, 0, speed, 0, stop)
    
    def zoom_in(self, speed: int = 4, stop: bool = False) -> bool:
        """放大"""
        return self.ptz_control(PTZCommand.ZOOM_ADD, 0, speed, 0, stop)
    
    def zoom_out(self, speed: int = 4, stop: bool = False) -> bool:
        """缩小"""
        return self.ptz_control(PTZCommand.ZOOM_DEC, 0, speed, 0, stop)
    
    def stop_move(self) -> bool:
        """停止移动"""
        # 发送停止命令
        self.move_up(0, True)
        self.move_left(0, True)
        self.zoom_in(0, True)
        return True
    
    def goto_exact_position(self, pan: float, tilt: float, zoom: int) -> bool:
        """
        三维精确定位
        Args:
            pan: 水平角度 (0-360度)
            tilt: 垂直角度 (-90到90度)
            zoom: 变倍 (1-128)
        Returns:
            是否成功
        """
        param1 = int(pan * 10)
        param2 = int(tilt * 10)
        param3 = int(min(zoom, 128))
        
        print(f"[PTZCamera] goto_exact_position: pan={pan:.1f}° tilt={tilt:.1f}° zoom={zoom} → p1={param1} p2={param2} p3={param3}")
        
        result = self.ptz_control(PTZCommand.EXACTGOTO, param1, param2, param3)
        
        if result:
            with self.position_lock:
                self.current_position = PTZPosition(pan=pan, tilt=tilt, zoom=zoom)
        else:
            print(f"[PTZCamera] goto_exact_position FAILED!")
        
        return result
    
    def goto_preset(self, preset_id: int) -> bool:
        """
        转到预置点
        Args:
            preset_id: 预置点ID
        Returns:
            是否成功
        """
        return self.ptz_control(PTZCommand.POINT_GO, 0, preset_id, 0)
    
    def set_preset(self, preset_id: int) -> bool:
        """
        设置预置点
        Args:
            preset_id: 预置点ID
        Returns:
            是否成功
        """
        return self.ptz_control(PTZCommand.POINT_SET, 0, preset_id, 0)
    
    def clear_preset(self, preset_id: int) -> bool:
        """
        清除预置点
        Args:
            preset_id: 预置点ID
        Returns:
            是否成功
        """
        return self.ptz_control(PTZCommand.POINT_CLEAR, 0, preset_id, 0)
    
    def calculate_ptz_position(self, x_ratio: float, y_ratio: float,
                                zoom: int = None) -> Tuple[float, float, int]:
        """
        根据全景画面中的位置计算PTZ角度
        Args:
            x_ratio: X方向比例 (0-1)
            y_ratio: Y方向比例 (0-1)
            zoom: 变倍 (默认使用配置值)
        Returns:
            (pan, tilt, zoom) PTZ位置
        """
        if zoom is None:
            zoom = self.ptz_config['default_zoom']
    
        # 应用坐标偏移校准
        offset_x, offset_y = self.ptz_config['coordinate_offset']
        x_ratio = max(0, min(1, x_ratio + offset_x))
        y_ratio = max(0, min(1, y_ratio + offset_y))
    
        # 从配置获取视野参数
        pan_range = self.ptz_config.get('pan_range', (0, 180))
        tilt_range = self.ptz_config.get('tilt_range', (-45, 45))
        pan_center = self.ptz_config.get('pan_center', 90)
        tilt_center = self.ptz_config.get('tilt_center', 0)
    
        # 将画面比例转换为角度
        # x_ratio=0 对应 pan_range[0], x_ratio=1 对应 pan_range[1]
        pan = pan_range[0] + (pan_range[1] - pan_range[0]) * x_ratio
    
        # y_ratio=0.5 对应 tilt_center, y_ratio=0 对应 tilt_range[0], y_ratio=1 对应 tilt_range[1]
        tilt = tilt_range[0] + (tilt_range[1] - tilt_range[0]) * y_ratio
            
        # 应用方向修正
        # 1. 检查安装类型，吸顶安装需要反转tilt
        mount_type = self.ptz_config.get('mount_type', 'wall')
        tilt_flip = self.ptz_config.get('tilt_flip', False)
            
        # 吸顶安装时自动反转tilt方向
        if mount_type == 'ceiling' or tilt_flip:
            # 反转tilt：原来的正角度变负，负角度变正
            tilt = -tilt
            print(f"[PTZCamera] 吸顶安装，tilt方向修正: {-tilt} -> {tilt}")
            
        # 2. 应用pan方向修正
        pan_flip = self.ptz_config.get('pan_flip', False)
        if pan_flip:
            # 反转pan方向（180度偏移）
            pan = (pan + 180) % 360
            print(f"[PTZCamera] pan方向翻转: {(pan - 180) % 360} -> {pan}")
    
        return (pan, tilt, zoom)
    
    def move_to_target(self, x_ratio: float, y_ratio: float, 
                       zoom: int = None) -> bool:
        """
        移动到目标位置
        Args:
            x_ratio: X方向比例 (0-1)
            y_ratio: Y方向比例 (0-1)
            zoom: 变倍
        Returns:
            是否成功
        """
        pan, tilt, zoom = self.calculate_ptz_position(x_ratio, y_ratio, zoom)
        return self.goto_exact_position(pan, tilt, zoom)
    
    def track_target(self, x_ratio: float, y_ratio: float, 
                     zoom: int = None) -> bool:
        """
        跟踪目标 - 与move_to_target相同，但可以添加跟踪特定逻辑
        Args:
            x_ratio: X方向比例
            y_ratio: Y方向比例
            zoom: 变倍
        Returns:
            是否成功
        """
        return self.move_to_target(x_ratio, y_ratio, zoom)
    
    def get_current_position(self) -> PTZPosition:
        """获取当前位置"""
        with self.position_lock:
            return PTZPosition(
                pan=self.current_position.pan,
                tilt=self.current_position.tilt,
                zoom=self.current_position.zoom
            )
    
    def goto_and_confirm(self, pan: float, tilt: float, zoom: int,
                         confirm_timeout: float = 1.0,
                         get_frame_func=None) -> dict:
        """
        PTZ精确定位并确认到位
        
        Args:
            pan, tilt, zoom: 目标位置
            confirm_timeout: 确认超时秒数
            get_frame_func: 获取球机帧的函数，用于验证
        
        Returns:
            dict: {'success': bool, 'pan': float, 'tilt': float, 'zoom': int,
                   'frame_available': bool, 'elapsed_ms': float}
        """
        import time as _time
        start = _time.time()
        
        success = self.goto_exact_position(pan, tilt, zoom)
        
        result = {
            'success': success,
            'pan': pan,
            'tilt': tilt,
            'zoom': zoom,
            'frame_available': False,
            'elapsed_ms': (_time.time() - start) * 1000
        }
        
        if not success:
            return result
        
        # 等待球机物理移动到位
        time.sleep(0.2)
        
        # 如果有帧获取函数，验证球机画面
        if get_frame_func is not None:
            deadline = _time.time() + confirm_timeout
            while _time.time() < deadline:
                frame = get_frame_func()
                if frame is not None:
                    result['frame_available'] = True
                    break
                time.sleep(0.05)
        
        result['elapsed_ms'] = (_time.time() - start) * 1000
        return result
    
    def is_position_close(self, target_pan: float, target_tilt: float,
                          threshold: float = 1.0) -> bool:
        """
        检查当前位置是否接近目标位置
        
        Args:
            target_pan: 目标水平角度
            target_tilt: 目标垂直角度
            threshold: 角度容差(度)
        """
        current = self.get_current_position()
        pan_diff = abs(current.pan - target_pan)
        tilt_diff = abs(current.tilt - target_tilt)
        return pan_diff <= threshold and tilt_diff <= threshold


class PTZController:
    """
    PTZ高级控制器
    提供平滑移动、跟踪等功能
    """
    
    def __init__(self, ptz_camera: PTZCamera):
        """
        初始化控制器
        Args:
            ptz_camera: PTZ摄像头实例
        """
        self.ptz = ptz_camera
        self.tracking = False
        self.tracking_thread = None
        self.target_position = None
    
    def smooth_move_to(self, pan: float, tilt: float, zoom: int,
                       steps: int = 10, delay: float = 0.1) -> bool:
        """
        平滑移动到目标位置
        Args:
            pan: 目标水平角度
            tilt: 目标垂直角度
            zoom: 目标变倍
            steps: 移动步数
            delay: 步间延迟
        Returns:
            是否成功
        """
        current = self.ptz.get_current_position()
        
        # 计算步长
        pan_step = (pan - current.pan) / steps
        tilt_step = (tilt - current.tilt) / steps
        zoom_step = (zoom - current.zoom) / steps
        
        for i in range(1, steps + 1):
            current_pan = current.pan + pan_step * i
            current_tilt = current.tilt + tilt_step * i
            current_zoom = int(current.zoom + zoom_step * i)
            
            self.ptz.goto_exact_position(current_pan, current_tilt, current_zoom)
            time.sleep(delay)
        
        return True
    
    def start_tracking(self, get_target_func, update_interval: float = 0.1):
        """
        开始跟踪
        Args:
            get_target_func: 获取目标位置的函数 (返回 x_ratio, y_ratio 或 None)
            update_interval: 更新间隔
        """
        self.tracking = True
        
        def tracking_worker():
            while self.tracking:
                try:
                    target = get_target_func()
                    if target:
                        x_ratio, y_ratio = target
                        self.ptz.track_target(x_ratio, y_ratio)
                    time.sleep(update_interval)
                except Exception as e:
                    print(f"跟踪错误: {e}")
                    time.sleep(0.1)
        
        self.tracking_thread = threading.Thread(target=tracking_worker, daemon=True)
        self.tracking_thread.start()
    
    def stop_tracking(self):
        """停止跟踪"""
        self.tracking = False
        if self.tracking_thread:
            self.tracking_thread.join(timeout=1)
            self.tracking_thread = None
    
    def zoom_to_target_size(self, target_size: Tuple[int, int],
                            frame_size: Tuple[int, int],
                            min_zoom: int = 2, max_zoom: int = 20) -> int:
        """
        根据目标大小计算合适的变倍
        Args:
            target_size: 目标尺寸 (width, height)
            frame_size: 画面尺寸 (width, height)
            min_zoom: 最小变倍
            max_zoom: 最大变倍
        Returns:
            计算的变倍值
        """
        target_area = target_size[0] * target_size[1]
        frame_area = frame_size[0] * frame_size[1]
        
        # 目标占画面比例
        ratio = target_area / frame_area
        
        # 根据比例计算变倍 (目标占画面30%时变倍为1)
        if ratio > 0:
            ideal_zoom = math.sqrt(0.3 / ratio)
            zoom = int(max(min_zoom, min(max_zoom, ideal_zoom)))
        else:
            zoom = min_zoom
        
        return zoom