"""
大华SDK Python封装
使用ctypes调用大华NetSDK
"""

import ctypes
import os
import threading
import queue
from ctypes import c_int, c_long, c_uint32, c_char_p, c_ubyte, POINTER, Structure, byref, CFUNCTYPE

# 大华SDK Linux类型映射 (dhnetsdk.h非Windows定义):
# DWORD = unsigned int (4 bytes) → c_uint32
# LONG  = int (4 bytes) → c_int
# LLONG = long (8 bytes on LP64) → c_long
# LDWORD = long (8 bytes on LP64) → c_long
from typing import Optional, Callable, Tuple, Dict, Any


class VideoFrameBuffer:
    """
    视频帧缓冲区
    用于SDK回调存储帧数据
    """
    def __init__(self, max_size: int = 10):
        self.buffer = queue.Queue(maxsize=max_size)
        self.lock = threading.Lock()
        self.latest_frame = None
    
    def put(self, frame_data: bytes, width: int, height: int, frame_type: int = 0):
        """存入帧数据"""
        with self.lock:
            self.latest_frame = {
                'data': frame_data,
                'width': width,
                'height': height,
                'type': frame_type
            }
        try:
            self.buffer.put_nowait(self.latest_frame)
        except queue.Full:
            pass
    
    def get(self, timeout: float = 0.1) -> Optional[Dict[str, Any]]:
        """获取帧数据"""
        try:
            return self.buffer.get(timeout=timeout)
        except queue.Empty:
            return None
    
    def get_latest(self) -> Optional[Dict[str, Any]]:
        """获取最新帧数据"""
        with self.lock:
            return self.latest_frame


# 加载SDK库
class DahuaSDK:
    """大华SDK封装类"""
    
    def __init__(self, lib_path: str):
        """
        初始化SDK
        Args:
            lib_path: SDK库文件路径
        """
        self.lib_path = lib_path
        self.sdk = None
        self.initialized = False
        self._disconnect_callback = None  # 保存回调引用，防止被垃圾回收
        
        # 视频回调相关
        self._video_callback = None
        self._video_frame_buffers: Dict[int, VideoFrameBuffer] = {}
        
        self._setup_structures()
        self._load_library()
    
    def _setup_structures(self):
        """设置SDK所需的C结构体"""
        
        # 登录输入参数 (必须与SDK头文件 NET_IN_LOGIN_WITH_HIGHLEVEL_SECURITY 严格对齐)
        class NET_IN_LOGIN_WITH_HIGHLEVEL_SECURITY(Structure):
            _fields_ = [
                ('dwSize', c_uint32),                    # DWORD = uint32
                ('szIP', ctypes.c_char * 64),            # IP
                ('nPort', c_int),                        # 端口
                ('szUserName', ctypes.c_char * 64),      # 用户名
                ('szPassword', ctypes.c_char * 64),      # 密码
                ('emSpecCap', c_int),                    # 登录模式
                ('byReserved', ctypes.c_ubyte * 4),      # 对齐保留
                ('pCapParam', ctypes.c_void_p),          # 扩展参数
                ('emTLSCap', c_int),                     # TLS模式
                ('szLocalIP', ctypes.c_char * 64),       # 本地IP
            ]
        
        # 设备信息 (NET_DEVICEINFO_Ex)
        class NET_DEVICEINFO_Ex(Structure):
            _fields_ = [
                ('sSerialNumber', ctypes.c_ubyte * 48),  # 序列号
                ('nAlarmInPortNum', c_int),               # 报警输入数
                ('nAlarmOutPortNum', c_int),              # 报警输出数
                ('nDiskNum', c_int),                       # 硬盘数
                ('nDVRType', c_int),                      # DVR类型
                ('nChanNum', c_int),                       # 通道数
                ('byLimitLoginTime', ctypes.c_ubyte),      # 限制登录时间
                ('byLeftLogTimes', ctypes.c_ubyte),        # 剩余登录次数
                ('bReserved', ctypes.c_ubyte * 2),        # 保留
                ('nLockLeftTime', c_int),                  # 锁定剩余时间
                ('Reserved', ctypes.c_char * 4),           # 保留
                ('nNTlsPort', c_int),                      # TLS端口
                ('nKeyFrameEncrypt', c_int),               # 关键帧加密
                ('emAlgorithm', c_int),                    # 加密算法
                ('Reserved2', ctypes.c_char * 8),          # 保留
            ]
        
        # 登录输出参数 (必须与SDK头文件严格对齐)
        class NET_OUT_LOGIN_WITH_HIGHLEVEL_SECURITY(Structure):
            _fields_ = [
                ('dwSize', c_uint32),                                    # DWORD = uint32
                ('stuDeviceInfo', NET_DEVICEINFO_Ex),                  # 设备信息
                ('nError', c_int),                                      # 错误码
                ('byReserved', ctypes.c_char * 132),                    # 保留
            ]
        
        # 抓拍参数
        class SNAP_PARAMS(Structure):
            _fields_ = [
                ('Channel', c_int),
                ('mode', c_int),
                ('CmdSerial', c_int),
                ('PicTransType', c_int),
                ('SendTotal', c_int),
                ('Quality', c_int),
                ('PicFormat', c_int),
                ('PicWidth', c_int),
                ('PicHeight', c_int),
                ('SnapDelayTime', c_int),
                ('byRes', ctypes.c_char * 12),
            ]
        
        self.NET_IN_LOGIN = NET_IN_LOGIN_WITH_HIGHLEVEL_SECURITY
        self.NET_OUT_LOGIN = NET_OUT_LOGIN_WITH_HIGHLEVEL_SECURITY
        self.SNAP_PARAMS = SNAP_PARAMS
    
    def _load_library(self):
        """加载SDK动态库"""
        try:
            lib_dir = os.path.dirname(self.lib_path)
            
            # 预加载依赖库 (确保库依赖能正确解析)
            # 大华SDK依赖 libcrypto.so, libssl.so 等
            if lib_dir:
                # 使用 RTLD_GLOBAL 标志加载依赖库，使其符号对后续库可见
                try:
                    # 尝试预加载常见的依赖库
                    for dep_lib in ['libcrypto.so', 'libssl.so']:
                        dep_path = os.path.join(lib_dir, dep_lib)
                        if os.path.exists(dep_path):
                            ctypes.CDLL(dep_path, mode=ctypes.RTLD_GLOBAL)
                except Exception as e:
                    # 依赖库加载失败不一定是致命错误，继续尝试加载主库
                    print(f"加载依赖库警告: {e}")
            
            # 加载主SDK库
            self.sdk = ctypes.CDLL(self.lib_path)
            self._setup_functions()
            self.initialized = True
            print(f"成功加载大华SDK: {self.lib_path}")
        except Exception as e:
            print(f"加载SDK失败: {e}")
            raise
    
    def _setup_functions(self):
        """设置SDK函数签名
        
        不同平台/版本的SDK可能缺少部分函数，用可选绑定处理：
        - 必需函数：缺失则初始化失败
        - 可选函数：缺失时设为None，运行时检查可用性
        
        注意: 在 Linux 上 BOOL = int (4 bytes)，不是 Windows 上的 bool (1 byte)
        所有返回 BOOL 的函数使用 c_int 作为返回值类型
        """
        
        # === 必需函数 ===
        
        # CLIENT_Init(BOOL (CALLBACK *cbDisConnect), LDWORD) -> BOOL
        self.sdk.CLIENT_Init.argtypes = [ctypes.c_void_p, c_long]
        self.sdk.CLIENT_Init.restype = c_int  # BOOL = int on Linux
        
        # CLIENT_Cleanup()
        self.sdk.CLIENT_Cleanup.argtypes = []
        self.sdk.CLIENT_Cleanup.restype = None
        
        # CLIENT_LoginWithHighLevelSecurity -> LLONG
        self.sdk.CLIENT_LoginWithHighLevelSecurity.argtypes = [
            POINTER(self.NET_IN_LOGIN),
            POINTER(self.NET_OUT_LOGIN)
        ]
        self.sdk.CLIENT_LoginWithHighLevelSecurity.restype = c_long
        
        # CLIENT_Logout(LLONG) -> BOOL
        self.sdk.CLIENT_Logout.argtypes = [c_long]
        self.sdk.CLIENT_Logout.restype = c_int  # BOOL = int on Linux
        
        # CLIENT_RealPlay(LLONG, int, void*) -> LLONG
        self.sdk.CLIENT_RealPlay.argtypes = [c_long, c_int, ctypes.c_void_p]
        self.sdk.CLIENT_RealPlay.restype = c_long
        
        # CLIENT_StopRealPlay(LLONG) -> BOOL
        self.sdk.CLIENT_StopRealPlay.argtypes = [c_long]
        self.sdk.CLIENT_StopRealPlay.restype = c_int  # BOOL = int on Linux
        
        # CLIENT_DHPTZControlEx(LLONG, int, DWORD, LONG, LONG, LONG, BOOL) -> BOOL
        # 注意: 在 Linux 上 BOOL = int (4 bytes)，不是 Windows 上的 bool
        # 使用 c_int 而不是 c_bool 以确保参数大小正确
        self.sdk.CLIENT_DHPTZControlEx.argtypes = [
            c_long, c_int, c_uint32, c_int, c_int, c_int, c_int
        ]
        self.sdk.CLIENT_DHPTZControlEx.restype = c_int  # BOOL = int on Linux
        
        # CLIENT_SnapPicture(LLONG, SNAP_PARAMS*) -> BOOL
        self.sdk.CLIENT_SnapPicture.argtypes = [c_long, POINTER(self.SNAP_PARAMS)]
        self.sdk.CLIENT_SnapPicture.restype = c_int  # BOOL = int on Linux
        
        # CLIENT_GetLastError() -> DWORD
        self.sdk.CLIENT_GetLastError.argtypes = []
        self.sdk.CLIENT_GetLastError.restype = c_uint32
        
        # === 可选函数（某些SDK版本/平台可能缺失）===
        self._optional_funcs = {}
        
        self._bind_optional('CLIENT_SetSnapRevCallBack', [ctypes.c_void_p, c_long], None)
        self._bind_optional('CLIENT_RealPlayEx', [c_long, c_int, ctypes.c_void_p, c_int], c_long)
        self._bind_optional('CLIENT_StopRealPlayEx', [c_long], c_int)  # BOOL = int on Linux
        self._bind_optional('CLIENT_SetVideoProcCallBack', [ctypes.c_void_p, c_long], None)
    
    def _bind_optional(self, name: str, argtypes: list, restype):
        """绑定可选SDK函数，缺失时设为None而不报错"""
        try:
            func = getattr(self.sdk, name, None)
            if func is not None:
                func.argtypes = argtypes
                func.restype = restype
                self._optional_funcs[name] = func
            else:
                self._optional_funcs[name] = None
                print(f"SDK可选函数缺失: {name}")
        except (AttributeError, OSError) as e:
            self._optional_funcs[name] = None
            print(f"SDK可选函数不可用: {name} - {e}")
    
    def _has_func(self, name: str) -> bool:
        """检查SDK函数是否可用"""
        return self._optional_funcs.get(name) is not None
    
    def init(self, disconnect_callback: Callable = None) -> bool:
        """
        初始化SDK
        Args:
            disconnect_callback: 断线回调函数
        Returns:
            是否成功
        """
        if not self.sdk:
            return False
        
        if disconnect_callback:
            # 保存回调引用，防止被垃圾回收
            # 回调签名: BOOL (CALLBACK *cbDisConnect)(LLONG lLoginID, char *pchDVRIP, LONG nDVRPort, LDWORD dwUser)
            # 在 Linux 上 BOOL = int，所以使用 c_int 作为返回值类型
            self._disconnect_callback = ctypes.CFUNCTYPE(
                c_int, c_long, c_char_p, c_int, c_long
            )(disconnect_callback)
        
        result = self.sdk.CLIENT_Init(self._disconnect_callback, 0)
        # SDK 返回 TRUE(非0) 表示成功
        self.initialized = (result != 0)
        return self.initialized
    
    def cleanup(self):
        """清理SDK资源"""
        if self.sdk and self.initialized:
            self.sdk.CLIENT_Cleanup()
            self.initialized = False
    
    def login(self, ip: str, port: int, username: str, password: str) -> Tuple[Optional[int], int]:
        """
        登录设备
        Args:
            ip: 设备IP
            port: 端口号
            username: 用户名
            password: 密码
        Returns:
            (登录句柄, 错误码) - 成功时错误码为0
        """
        if not self.sdk:
            return None, -1
        
        in_param = self.NET_IN_LOGIN()
        in_param.dwSize = ctypes.sizeof(self.NET_IN_LOGIN)
        in_param.szIP = ip.encode('utf-8')
        in_param.nPort = port
        in_param.szUserName = username.encode('utf-8')
        in_param.szPassword = password.encode('utf-8')
        in_param.emSpecCap = 0  # EM_LOGIN_SPEC_CAP_TCP
        
        out_param = self.NET_OUT_LOGIN()
        out_param.dwSize = ctypes.sizeof(self.NET_OUT_LOGIN)
        
        login_handle = self.sdk.CLIENT_LoginWithHighLevelSecurity(
            byref(in_param), byref(out_param)
        )
        
        if login_handle == 0:
            return None, out_param.nError
        
        return login_handle, 0
    
    def logout(self, login_handle: int) -> bool:
        """登出设备"""
        if not self.sdk or login_handle <= 0:
            return False
        result = self.sdk.CLIENT_Logout(login_handle)
        return result != 0  # SDK 返回 TRUE(非0) 表示成功
    
    def real_play(self, login_handle: int, channel: int = 0) -> Optional[int]:
        """
        开始实时预览
        Args:
            login_handle: 登录句柄
            channel: 通道号
        Returns:
            预览句柄
        """
        if not self.sdk or login_handle <= 0:
            return None
        play_handle = self.sdk.CLIENT_RealPlay(login_handle, channel, None)
        return play_handle if play_handle > 0 else None
    
    def real_play_ex(self, login_handle: int, channel: int = 0, 
                     use_callback: bool = True) -> Optional[int]:
        if not self.sdk or login_handle <= 0:
            return None
        
        if not self._has_func('CLIENT_RealPlayEx'):
            return self.real_play(login_handle, channel)
        
        if use_callback and self._has_func('CLIENT_SetVideoProcCallBack'):
            if channel not in self._video_frame_buffers:
                self._video_frame_buffers[channel] = VideoFrameBuffer()
            if self._video_callback is None:
                self._setup_video_callback()
            play_handle = self.sdk.CLIENT_RealPlayEx(login_handle, channel, None, 0)
        else:
            play_handle = self.sdk.CLIENT_RealPlayEx(login_handle, channel, None, 0) if self._has_func('CLIENT_RealPlayEx') else self.real_play(login_handle, channel)
        
        return play_handle if play_handle > 0 else None
    
    def _setup_video_callback(self):
        if not self._has_func('CLIENT_SetVideoProcCallBack'):
            print("SDK不支持CLIENT_SetVideoProcCallBack，视频回调不可用")
            return
        
        def video_callback(real_handle: c_long, data_type: c_uint32, 
                          buffer: POINTER(c_ubyte), buf_size: c_uint32,
                          param: c_long, user_data: c_long):
            if data_type == 1 and buf_size > 0:
                pass
        
        self._video_callback = CFUNCTYPE(
            None, c_long, c_uint32, POINTER(c_ubyte), c_uint32, c_long, c_long
        )(video_callback)
        
        self.sdk.CLIENT_SetVideoProcCallBack(self._video_callback, 0)
    
    def get_video_frame_buffer(self, channel: int = 0) -> Optional[VideoFrameBuffer]:
        """获取视频帧缓冲区"""
        return self._video_frame_buffers.get(channel)
    
    def stop_real_play(self, play_handle: int) -> bool:
        """停止实时预览"""
        if not self.sdk or play_handle <= 0:
            return False
        result = self.sdk.CLIENT_StopRealPlay(play_handle)
        return result != 0  # SDK 返回 TRUE(非0) 表示成功
    
    def ptz_control(self, login_handle: int, channel: int, 
                    command: int, param1: int, param2: int, param3: int,
                    stop: bool = False) -> bool:
        """
        PTZ控制
        Args:
            login_handle: 登录句柄
            channel: 通道号
            command: 控制命令 (DH_EXTPTZ_ControlType)
            param1-param3: 控制参数
            stop: 是否停止(用于持续移动)
        Returns:
            是否成功
        """
        if not self.sdk or login_handle <= 0:
            print(f"[PTZ] 失败: sdk={self.sdk is not None}, handle={login_handle}")
            return False
        
        # 命令名称映射 (用于调试日志)
        cmd_names = {
            0: 'UP', 1: 'DOWN', 2: 'LEFT', 3: 'RIGHT',
            4: 'ZOOM_ADD', 5: 'ZOOM_DEC',
            0x20: 'LEFTTOP', 0x21: 'RIGHTTOP', 0x22: 'LEFTDOWN', 0x23: 'RIGHTDOWN',
            0x33: 'FASTGOTO', 0x43: 'EXACTGOTO', 0x44: 'RESETZERO',
            0x45: 'MOVE_ABSOLUTELY', 0x46: 'MOVE_CONTINUOUSLY', 0x47: 'GOTOPRESET',
        }
        cmd_name = cmd_names.get(command, f'CMD_{command:#x}')
        
        # 将 stop (bool) 转换为 int (TRUE=1, FALSE=0)，匹配 Linux SDK 的 BOOL 定义
        stop_int = 1 if stop else 0
        
        result = self.sdk.CLIENT_DHPTZControlEx(
            login_handle, channel, command, param1, param2, param3, stop_int
        )
        
        # SDK 返回 TRUE(非0) 表示成功，FALSE(0) 表示失败
        success = (result != 0)
        
        print(f"[PTZ] {cmd_name}(ch={channel}, p1={param1}, p2={param2}, p3={param3}, stop={stop}) → {'✓' if success else '✗'} (ret={result})")
        
        if not success:
            # 获取SDK错误码
            error = self.sdk.CLIENT_GetLastError() if hasattr(self.sdk, 'CLIENT_GetLastError') else -1
            print(f"[PTZ] 错误码: {error}")
        
        return success
    
    def snap_picture(self, login_handle: int, channel: int = 0, 
                     cmd_serial: int = 0) -> bool:
        """
        抓拍图片
        Args:
            login_handle: 登录句柄
            channel: 通道号
            cmd_serial: 命令序列号
        Returns:
            是否成功
        """
        if not self.sdk or login_handle <= 0:
            return False
        
        params = self.SNAP_PARAMS()
        params.Channel = channel
        params.mode = 0  # SNAP_TYP_TIMING
        params.CmdSerial = cmd_serial
        params.PicTransType = 0
        params.Quality = 1
        params.PicFormat = 0  # BMP
        
        result = self.sdk.CLIENT_SnapPicture(login_handle, byref(params))
        return result != 0  # SDK 返回 TRUE(非0) 表示成功


# PTZ控制命令常量 (从dhnetsdk.h提取)
class PTZCommand:
    """PTZ控制命令常量 (DH_EXTPTZ_ControlType from dhnetsdk.h)"""
    
    # 基本控制 (DH_PTZ_ControlType)
    UP = 0
    DOWN = 1
    LEFT = 2
    RIGHT = 3
    ZOOM_ADD = 4
    ZOOM_DEC = 5
    FOCUS_ADD = 6
    FOCUS_DEC = 7
    APERTURE_ADD = 8
    APERTURE_DEC = 9
    
    # 扩展控制 (DH_EXTPTZ_ControlType, 从0x20开始)
    LEFTTOP = 0x20
    RIGHTTOP = 0x21
    LEFTDOWN = 0x22
    RIGHTDOWN = 0x23
    ADDTOLOOP = 0x24
    DELFROMLOOP = 0x25
    CLOSELOOP = 0x26
    STARTPANCRUISE = 0x27
    STOPPANCRUISE = 0x28
    SETLEFTBORDER = 0x29
    SETRIGHTBORDER = 0x2a
    STARTLINESCAN = 0x2b
    CLOSELINESCAN = 0x2c
    SETMODESTART = 0x2d
    SETMODESTOP = 0x2e
    RUNMODE = 0x2f
    STOPMODE = 0x30
    DELETEMODE = 0x31
    REVERSECOMM = 0x32
    FASTGOTO = 0x33
    AUXIOPEN = 0x34
    AUXICLOSE = 0x35
    OPENMENU = 0x36
    CLOSEMENU = 0x37
    MENUOK = 0x38
    MENUCANCEL = 0x39
    MENUUP = 0x3a
    MENUDOWN = 0x3b
    MENULEFT = 0x3c
    MENURIGHT = 0x3d
    ALARMHANDLE = 0x40
    MATRIXSWITCH = 0x41
    LIGHTCONTROL = 0x42
    EXACTGOTO = 0x43       # 三维精确定位
    RESETZERO = 0x44
    MOVE_ABSOLUTELY = 0x45
    MOVE_CONTINUOUSLY = 0x46
    GOTOPRESET = 0x47
    SET_VIEW_RANGE = 0x49
    FOCUS_ABSOLUTELY = 0x4a


class SDKError:
    """SDK错误码"""
    SUCCESS = 0
    NET_ERROR_PASSWORD = 1
    NET_ERROR_USER = 2
    NET_ERROR_TIMEOUT = 3
    NET_ERROR_RECONNECT = 4