#import <AVFoundation/AVFoundation.h>
#import <UIKit/UIKit.h>

/// 通过名称查找摄像头设备
static AVCaptureDevice *FindCameraByName(const char *cameraName)
{
    if (cameraName == NULL || strlen(cameraName) == 0) {
        return [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    }

    NSString *name = [NSString stringWithUTF8String:cameraName];

    // iOS 10+ DiscoverySession
    if (@available(iOS 10.0, *)) {
        AVCaptureDeviceDiscoverySession *session = [AVCaptureDeviceDiscoverySession
            discoverySessionWithDeviceTypes:@[AVCaptureDeviceTypeBuiltInWideAngleCamera,
                                              AVCaptureDeviceTypeBuiltInTelephotoCamera,
                                              AVCaptureDeviceTypeBuiltInUltraWideCamera]
                                  mediaType:AVMediaTypeVideo
                                   position:AVCaptureDevicePositionUnspecified];
        for (AVCaptureDevice *device in session.devices) {
            if ([device.localizedName containsString:name] ||
                [device.modelID containsString:name]) {
                return device;
            }
        }
        // 没找到精确匹配，返回第一个活跃的
        for (AVCaptureDevice *device in session.devices) {
            if (device.isConnected && !device.isSuspended) {
                return device;
            }
        }
    }

    return [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
}

extern "C" {

    /// 启用连续自动对焦和自动曝光（传入 C# 选中的摄像头名称）
    void _EnableContinuousAutoFocus(const char *cameraName)
    {
        dispatch_async(dispatch_get_main_queue(), ^{
            AVCaptureDevice *device = FindCameraByName(cameraName);
            if (!device) {
                NSLog(@"[CameraFocusHelper] 未找到摄像头设备");
                return;
            }

            NSLog(@"[CameraFocusHelper] 配置设备: %@ (name=%@, model=%@)",
                  device.localizedName, device.localizedName, device.modelID);

            NSError *error = nil;
            if ([device lockForConfiguration:&error]) {

                // 连续自动对焦
                if ([device isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus]) {
                    device.focusMode = AVCaptureFocusModeContinuousAutoFocus;
                    NSLog(@"[CameraFocusHelper] 已设为连续自动对焦");
                } else {
                    NSLog(@"[CameraFocusHelper] 设备不支持连续自动对焦");
                }

                // 连续自动曝光
                if ([device isExposureModeSupported:AVCaptureExposureModeContinuousAutoExposure]) {
                    device.exposureMode = AVCaptureExposureModeContinuousAutoExposure;
                }

                // 对焦范围限制为近距
                if ([device respondsToSelector:@selector(isAutoFocusRangeRestrictionSupported)] &&
                    [device isAutoFocusRangeRestrictionSupported]) {
                    device.autoFocusRangeRestriction = AVCaptureAutoFocusRangeRestrictionNear;
                    NSLog(@"[CameraFocusHelper] 已设对焦范围为近距");
                }

                [device unlockForConfiguration];
                NSLog(@"[CameraFocusHelper] 摄像头配置完成");
            } else {
                NSLog(@"[CameraFocusHelper] lockForConfiguration 失败: %@", error.localizedDescription);
            }
        });
    }

    /// 确保连续自动对焦仍在生效（传入 C# 选中的摄像头名称）
    void _EnsureContinuousAutoFocus(const char *cameraName)
    {
        dispatch_async(dispatch_get_main_queue(), ^{
            AVCaptureDevice *device = FindCameraByName(cameraName);
            if (!device) return;

            NSError *error = nil;
            if ([device lockForConfiguration:&error]) {
                if (device.focusMode != AVCaptureFocusModeContinuousAutoFocus &&
                    [device isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus]) {
                    device.focusMode = AVCaptureFocusModeContinuousAutoFocus;
                    NSLog(@"[CameraFocusHelper] 重新设回连续自动对焦");
                }
                [device unlockForConfiguration];
            }
        });
    }

}