using Microsoft.AspNetCore.Mvc;

namespace SHH.CameraSdk;

[ApiController]
[Route("api/[controller]")]
public class CamerasController : ControllerBase
{
    private readonly CameraManager _manager;

    public CamerasController(CameraManager manager)
    {
        _manager = manager;
    }

    // ==========================================================================
    // 区域 A: 设备全生命周期管理 (CRUD)
    // ==========================================================================

    /// <summary>
    /// 1. 获取所有设备清单
    /// </summary>
    [HttpGet]
    public IActionResult GetAll()
    {
        var devices = _manager.GetAllDevices().Select(d => new
        {
            d.Id,
            d.Config.IpAddress,
            d.Config.Name,
            Status = d.Status.ToString(),
            d.RealFps,
            d.TotalFrames
        });
        return Ok(devices);
    }

    /// <summary>
    /// 2. 新增设备 (写入配置并初始化)
    /// </summary>
    [HttpPost]
    public IActionResult Add([FromBody] CameraConfigDto dto)
    {
        if (_manager.GetDevice(dto.Id) != null)
            return Conflict($"设备ID {dto.Id} 已存在");

        // DTO 转 Config (实际项目中建议用 AutoMapper)
        var config = MapToConfig(dto);

        _manager.AddDevice(config); // 添加到内存池
                                    // 注意：此时 IsRunning 默认为 false，等待手动 Start 或 API 控制

        return CreatedAtAction(nameof(GetAll), new { id = dto.Id }, dto);
    }

    /// <summary>
    /// 3. 编辑设备 (自动识别冷热更新)
    /// </summary>
    [HttpPut("{id}")]
    public async Task<IActionResult> Update(long id, [FromBody] CameraConfigDto dto)
    {
        try
        {
            if (id != dto.Id) return BadRequest("ID 不匹配");

            // 调用 Manager 的智能更新逻辑 (之前实现的 UpdateDeviceConfigAsync)
            await _manager.UpdateDeviceConfigAsync(id, MapToUpdateDto(dto));

            return Ok(new { Success = true, Message = "配置已更新" });
        }
        catch (KeyNotFoundException) { return NotFound(); }
        catch (System.Exception ex) { return StatusCode(500, ex.Message); }
    }

    /// <summary>
    /// 4. 删除设备 (销毁连接)
    /// </summary>
    [HttpDelete("{id}")]
    public async Task<IActionResult> Remove(long id)
    {
        var device = _manager.GetDevice(id);
        if (device == null) return NotFound();

        await device.StopAsync(); // 停流
        _manager.RemoveDevice(id); // 从池中移除

        return Ok($"设备 {id} 已移除");
    }

    // ==========================================================================
    // 区域 B: 多进程流控订阅 (Subscription Strategy)
    // ==========================================================================

    /// <summary>
    /// 5. 注册/更新进程的流需求 (A/B/C/D 场景核心)
    /// </summary>
    /// <remarks>
    /// 示例场景：
    /// - 主进程配置(B): { "appId": "Main_Config", "displayFps": 25, "analysisFps": 0 }
    /// - AI进程(C):    { "appId": "AI_Core", "displayFps": 0, "analysisFps": 5 }
    /// </remarks>
    [HttpPost("{id}/subscriptions")]
    public IActionResult UpdateSubscription(long id, [FromBody] SubscriptionDto sub)
    {
        var device = _manager.GetDevice(id);
        if (device == null) return NotFound();

        // 逻辑转换：将 "显示帧" 和 "分析帧" 映射到底层控制器的注册表

        // 1. 处理显示需求
        string displayKey = $"{sub.AppId}_Display";
        if (sub.DisplayFps > 0)
        {
            // 告诉控制器：这个 App 需要 X 帧用于显示
            device.Controller.Register(displayKey, sub.DisplayFps);
        }
        else
        {
            // 如果不需要，移除注册
            device.Controller.Unregister(displayKey);
        }

        // 2. 处理分析需求
        string analysisKey = $"{sub.AppId}_Analysis";
        if (sub.AnalysisFps > 0)
        {
            // 告诉控制器：这个 App 需要 Y 帧用于分析
            device.Controller.Register(analysisKey, sub.AnalysisFps);
        }
        else
        {
            device.Controller.Unregister(analysisKey);
        }

        // 运维审计
        device.AddAuditLog($"更新订阅策略 [{sub.AppId}]: Display={sub.DisplayFps}, Analysis={sub.AnalysisFps}");

        return Ok(new { Message = "订阅策略已更新", DeviceId = id });
    }

    // ==========================================================================
    // 区域 C: 句柄动态绑定 (Handle Binding)
    // ==========================================================================

    /// <summary>
    /// 6. 绑定显示窗口 (对应 A进程-句柄场景)
    /// </summary>
    [HttpPost("{id}/bind-handle")]
    public IActionResult BindHandle(long id, [FromBody] BindHandleDto dto)
    {
        var device = _manager.GetDevice(id);
        if (device == null) return NotFound();

        // 构造动态选项，应用句柄
        var options = new DynamicStreamOptions
        {
            RenderHandle = (System.IntPtr)dto.Handle
        };

        device.ApplyOptions(options); // 触发驱动层的 OnApplyOptions

        device.AddAuditLog($"绑定新句柄: {dto.Handle} ({dto.Purpose})");

        return Ok(new { Success = true });
    }

    // ==========================================================================
    // 区域 D: 设备运行控制
    // ==========================================================================

    /// <summary>
    /// 手动控制设备运行状态 (开关机)
    /// </summary>
    [HttpPost("{id}/power")]
    public async Task<IActionResult> TogglePower(long id, [FromQuery] bool enabled)
    {
        var device = _manager.GetDevice(id);
        if (device == null) return NotFound();

        // 1. 更新运行意图
        device.IsRunning = enabled;

        // 2. 审计与执行
        if (enabled)
        {
            device.AddAuditLog("用户指令：手动开启设备");
            // 异步启动，Coordinator 也会在下个周期辅助检查
            _ = device.StartAsync();
        }
        else
        {
            device.AddAuditLog("用户指令：手动关闭设备");
            await device.StopAsync();
        }

        return Ok(new { DeviceId = id, IsRunning = enabled });
    }

    /// <summary>
    /// 热应用动态参数 (如切换码流)
    /// </summary>
    [HttpPost("{id}/options")]
    public IActionResult ApplyOptions(long id, [FromBody] DynamicStreamOptions options)
    {
        var device = _manager.GetDevice(id);
        if (device == null) return NotFound();

        // 1. 如果涉及码流切换，先同步更新配置对象
        if (options.StreamType.HasValue)
        {
            var newConfig = device.Config.DeepCopy();
            newConfig.StreamType = options.StreamType.Value;
            device.UpdateConfig(newConfig);
        }

        // 2. 应用到驱动层（触发热切换逻辑）
        device.ApplyOptions(options);

        return Ok(new { Message = "动态参数已发送", DeviceId = id });
    }

    // ==========================================================================
    // 辅助方法 (Mapping)
    // ==========================================================================
    private VideoSourceConfig MapToConfig(CameraConfigDto dto)
    {
        return new VideoSourceConfig
        {
            Id = dto.Id,
            Name = dto.Name,
            Brand = (DeviceBrand)dto.Brand,
            IpAddress = dto.IpAddress,
            Port = dto.Port,
            Username = dto.Username,
            Password = dto.Password,
            ChannelIndex = dto.ChannelIndex,
            StreamType = dto.StreamType,
            RtspPath = dto.RtspPath
        };
    }

    /// <summary>
    /// [辅助方法] 将全量配置 DTO 转换为更新 DTO
    /// </summary>
    private DeviceUpdateDto MapToUpdateDto(CameraConfigDto dto)
    {
        return new DeviceUpdateDto
        {
            // ==========================================
            // 1. 冷更新参数 (基础连接信息)
            // ==========================================
            IpAddress = dto.IpAddress,
            Port = dto.Port,
            Username = dto.Username,
            Password = dto.Password,
            ChannelIndex = dto.ChannelIndex,
            Brand = dto.Brand,
            RtspPath = dto.RtspPath,
            MainboardIp = dto.MainboardIp,
            MainboardPort = dto.MainboardPort,

            // ==========================================
            // 2. 热更新参数 (运行时属性)
            // ==========================================
            Name = dto.Name,
            Location = dto.Location,
            StreamType = dto.StreamType,

            // 注意：通常句柄是通过 bind-handle 接口单独绑定的，
            // 但如果 ConfigDto 里包含了上次保存的句柄，也可以映射
            // RenderHandle = dto.RenderHandle, 

            // ==========================================
            // 3. 图像处理参数
            // ==========================================
            AllowCompress = dto.AllowCompress,
            AllowExpand = dto.AllowExpand,
            TargetResolution = dto.TargetResolution,
            EnhanceImage = dto.EnhanceImage,
            UseGrayscale = dto.UseGrayscale
        };
    }

    /// <summary>
    /// [新增] 查询某台设备的当前流控策略
    /// </summary>
    [HttpGet("{id}/subscriptions")]
    public IActionResult GetSubscriptions(long id)
    {
        var device = _manager.GetDevice(id);
        if (device == null) return NotFound();

        // 调用刚才在 FrameController 写的方法
        var subs = device.Controller.GetCurrentRequirements();

        return Ok(subs);
    }
}