#import "HWPhotoVC.h"
#import <AVFoundation/AVFoundation.h>
 
@interface HWPhotoVC ()
 
@property (nonatomic, strong) AVCaptureSession *captureSession;//負(fù)責(zé)輸入和輸出設(shè)備之間的數(shù)據(jù)傳遞
@property (nonatomic, strong) AVCaptureDeviceInput *captureDeviceInput;//負(fù)責(zé)從AVCaptureDevice獲得輸入數(shù)據(jù)
@property (nonatomic, strong) AVCaptureStillImageOutput *captureStillImageOutput;//照片輸出流
@property (nonatomic, strong) AVCaptureVideoPreviewLayer *captureVideoPreviewLayer;//相機(jī)拍攝預(yù)覽圖層
@property (nonatomic, weak) UIView *containerView;//內(nèi)容視圖
@property (nonatomic, weak) UIImageView *focusCursor;//聚焦按鈕
@property (nonatomic, weak) UIImageView *imgView;//拍攝照片
 
@end
 
@implementation HWPhotoVC
 
- (void)viewDidLoad {
 [super viewDidLoad];
 
 self.navigationItem.title = @"拍照";
 self.view.backgroundColor = [UIColor whiteColor];
 
 //創(chuàng)建控件
 [self creatControl];
}
 
- (void)viewWillAppear:(BOOL)animated
{
 [super viewWillAppear:animated];
 
 //初始化信息
 [self initPhotoInfo];
}
 
- (void)viewDidAppear:(BOOL)animated
{
 [super viewDidAppear:animated];
 
 [self.captureSession startRunning];
}
 
- (void)viewDidDisappear:(BOOL)animated
{
 [super viewDidDisappear:animated];
 
 [self.captureSession stopRunning];
}
 
- (void)creatControl
{
 CGFloat btnW = 150.f;
 CGFloat btnH = 40.f;
 CGFloat marginY = 20.f;
 CGFloat w = [UIScreen mainScreen].bounds.size.width;
 CGFloat h = [UIScreen mainScreen].bounds.size.height;
 
 //內(nèi)容視圖
 CGFloat containerViewH = h - 64 - btnH - marginY * 3;
 UIView *containerView = [[UIView alloc] initWithFrame:CGRectMake(10, 64 + marginY, w - 20, containerViewH)];
 containerView.backgroundColor = [UIColor whiteColor];
 containerView.layer.borderWidth = 1.f;
 containerView.layer.borderColor = [[UIColor grayColor] CGColor];
 [self.view addSubview:containerView];
 _containerView = containerView;
 
 //攝像頭切換按鈕
 CGFloat cameraSwitchBtnW = 50.f;
 CGFloat cameraSwitchBtnMargin = 10.f;
 UIButton *cameraSwitchBtn = [[UIButton alloc] initWithFrame:CGRectMake(containerView.bounds.size.width - cameraSwitchBtnW - cameraSwitchBtnMargin, 64 + marginY + cameraSwitchBtnMargin, cameraSwitchBtnW, cameraSwitchBtnW)];
 [cameraSwitchBtn setImage:[UIImage imageNamed:@"camera_switch"] forState:UIControlStateNormal];
 [cameraSwitchBtn addTarget:self action:@selector(cameraSwitchBtnOnClick) forControlEvents:UIControlEventTouchUpInside];
 [self.view addSubview:cameraSwitchBtn];
 
 //聚焦圖片
 UIImageView *focusCursor = [[UIImageView alloc] initWithFrame:CGRectMake(50, 50, 75, 75)];
 focusCursor.alpha = 0;
 focusCursor.image = [UIImage imageNamed:@"camera_focus_red"];
 [containerView addSubview:focusCursor];
 _focusCursor = focusCursor;
 
 //拍攝照片容器
 UIImageView *imgView = [[UIImageView alloc] initWithFrame:containerView.frame];
 imgView.hidden = YES;
 imgView.layer.borderWidth = 1.f;
 imgView.layer.borderColor = [[UIColor grayColor] CGColor];
 imgView.contentMode = UIViewContentModeScaleAspectFill;
 imgView.clipsToBounds = YES;
 [self.view addSubview:imgView];
 _imgView = imgView;
 
 //按鈕
 NSArray *titleArray = @[@"拍攝照片", @"重新拍攝"];
 CGFloat btnY = CGRectGetMaxY(containerView.frame) + marginY;
 CGFloat margin = (w - btnW * titleArray.count) / (titleArray.count + 1);
 for (int i = 0; i < titleArray.count; i++) {
  CGFloat btnX = margin + (margin + btnW) * i;
  UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake(btnX, btnY, btnW, btnH)];
  btn.tag = 1000 + i;
  [btn setTitle:titleArray[i] forState:UIControlStateNormal];
  btn.backgroundColor = [UIColor orangeColor];
  btn.layer.cornerRadius = 2.0f;
  btn.layer.masksToBounds = YES;
  if (i == 1) {
   btn.hidden = YES;
  }
  [btn addTarget:self action:@selector(btnOnClick:) forControlEvents:UIControlEventTouchUpInside];
  [self.view addSubview:btn];
 }
}
 
- (void)initPhotoInfo
{
 //初始化會話
 _captureSession = [[AVCaptureSession alloc] init];
 
 //設(shè)置分辨率
 if ([_captureSession canSetSessionPreset:AVCaptureSessionPreset1280x720]) {
  _captureSession.sessionPreset = AVCaptureSessionPreset1280x720;
 }
 
 //獲得輸入設(shè)備,取得后置攝像頭
 AVCaptureDevice *captureDevice = [self getCameraDeviceWithPosition:AVCaptureDevicePositionBack];
 if (!captureDevice) {
  NSLog(@"取得后置攝像頭時出現(xiàn)問題");
  return;
 }
 
 NSError *error = nil;
 //根據(jù)輸入設(shè)備初始化設(shè)備輸入對象，用于獲得輸入數(shù)據(jù)
 _captureDeviceInput = [[AVCaptureDeviceInput alloc]initWithDevice:captureDevice error:&error];
 if (error) {
  NSLog(@"取得設(shè)備輸入對象時出錯，錯誤原因：%@", error.localizedDescription);
  return;
 }
 
 //初始化設(shè)備輸出對象，用于獲得輸出數(shù)據(jù)
 _captureStillImageOutput = [[AVCaptureStillImageOutput alloc] init];
 NSDictionary *outputSettings = @{AVVideoCodecKey:AVVideoCodecJPEG};
 //輸出設(shè)置
 [_captureStillImageOutput setOutputSettings:outputSettings];
 
 //將設(shè)備輸入添加到會話中
 if ([_captureSession canAddInput:_captureDeviceInput]) {
  [_captureSession addInput:_captureDeviceInput];
 }
 
 //將設(shè)備輸出添加到會話中
 if ([_captureSession canAddOutput:_captureStillImageOutput]) {
  [_captureSession addOutput:_captureStillImageOutput];
 }
 
 //創(chuàng)建視頻預(yù)覽層，用于實時展示攝像頭狀態(tài)
 _captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:self.captureSession];
 
 //攝像頭方向
 AVCaptureConnection *captureConnection = [self.captureVideoPreviewLayer connection];
 captureConnection.videoOrientation = AVCaptureVideoOrientationPortrait;
 
 CALayer *layer = _containerView.layer;
 layer.masksToBounds = YES;
 
 _captureVideoPreviewLayer.frame = layer.bounds;
 //填充模式
 _captureVideoPreviewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
 //將視頻預(yù)覽層添加到界面中
 [layer insertSublayer:_captureVideoPreviewLayer below:self.focusCursor.layer];
 
 [self addNotificationToCaptureDevice:captureDevice];
 [self addGenstureRecognizer];
}
 
- (void)btnOnClick:(UIButton *)btn
{
 if (btn.tag == 1000) {
  //拍攝照片
  [self photoBtnOnClick];
  
 }else if (btn.tag == 1001) {
  //重新拍攝
  [self resetPhoto];
 }
}
 
#pragma mark 拍照
- (void)photoBtnOnClick
{
 //根據(jù)設(shè)備輸出獲得連接
 AVCaptureConnection *captureConnection = [self.captureStillImageOutput connectionWithMediaType:AVMediaTypeVideo];
 captureConnection.videoOrientation = AVCaptureVideoOrientationPortrait;
 
 //根據(jù)連接取得設(shè)備輸出的數(shù)據(jù)
 [self.captureStillImageOutput captureStillImageAsynchronouslyFromConnection:captureConnection completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) {
  if (imageDataSampleBuffer) {
   NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
   UIImage *image = [UIImage imageWithData:imageData];
   _imgView.image = image;
   _imgView.hidden = NO;
  }
 }];
 
 UIButton *btn = (UIButton *)[self.view viewWithTag:1001];
 btn.hidden = NO;
}
 
//重新拍攝
- (void)resetPhoto
{
 _imgView.hidden = YES;
 UIButton *btn = (UIButton *)[self.view viewWithTag:1001];
 btn.hidden = YES;
}
 
#pragma mark - 通知
//給輸入設(shè)備添加通知
- (void)addNotificationToCaptureDevice:(AVCaptureDevice *)captureDevice
{
 //注意添加區(qū)域改變捕獲通知必須首先設(shè)置設(shè)備允許捕獲
 [self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
  captureDevice.subjectAreaChangeMonitoringEnabled = YES;
 }];
 
 //捕獲區(qū)域發(fā)生改變
 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(areaChange:) name:AVCaptureDeviceSubjectAreaDidChangeNotification object:captureDevice];
}
 
- (void)removeNotificationFromCaptureDevice:(AVCaptureDevice *)captureDevice
{
 [[NSNotificationCenter defaultCenter] removeObserver:self name:AVCaptureDeviceSubjectAreaDidChangeNotification object:captureDevice];
}
 
//移除所有通知
- (void)removeNotification
{
 [[NSNotificationCenter defaultCenter] removeObserver:self];
}
 
//設(shè)備連接成功
- (void)deviceConnected:(NSNotification *)notification
{
 NSLog(@"設(shè)備已連接...");
}
 
//設(shè)備連接斷開
- (void)deviceDisconnected:(NSNotification *)notification
{
 NSLog(@"設(shè)備已斷開.");
}
 
//捕獲區(qū)域改變
- (void)areaChange:(NSNotification *)notification
{
 NSLog(@"捕獲區(qū)域改變...");
}
 
#pragma mark - 私有方法
//取得指定位置的攝像頭
- (AVCaptureDevice *)getCameraDeviceWithPosition:(AVCaptureDevicePosition )position
{
 NSArray *cameras = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
 for (AVCaptureDevice *camera in cameras) {
  if ([camera position] == position) {
   return camera;
  }
 }
 
 return nil;
}
 
#pragma mark 切換前后攝像頭
- (void)cameraSwitchBtnOnClick
{
 AVCaptureDevice *currentDevice = [self.captureDeviceInput device];
 AVCaptureDevicePosition currentPosition = [currentDevice position];
 [self removeNotificationFromCaptureDevice:currentDevice];
 
 AVCaptureDevice *toChangeDevice;
 AVCaptureDevicePosition toChangePosition = AVCaptureDevicePositionFront;
 if (currentPosition == AVCaptureDevicePositionUnspecified || currentPosition == AVCaptureDevicePositionFront) {
  toChangePosition = AVCaptureDevicePositionBack;
 }
 toChangeDevice = [self getCameraDeviceWithPosition:toChangePosition];
 [self addNotificationToCaptureDevice:toChangeDevice];
 //獲得要調(diào)整的設(shè)備輸入對象
 AVCaptureDeviceInput *toChangeDeviceInput = [[AVCaptureDeviceInput alloc] initWithDevice:toChangeDevice error:nil];
 
 //改變會話的配置前一定要先開啟配置，配置完成后提交配置改變
 [self.captureSession beginConfiguration];
 //移除原有輸入對象
 [self.captureSession removeInput:self.captureDeviceInput];
 //添加新的輸入對象
 if ([self.captureSession canAddInput:toChangeDeviceInput]) {
  [self.captureSession addInput:toChangeDeviceInput];
  self.captureDeviceInput = toChangeDeviceInput;
 }
 //提交會話配置
 [self.captureSession commitConfiguration];
}
 
//改變設(shè)備屬性的統(tǒng)一操作方法
- (void)changeDeviceProperty:(void (^)(AVCaptureDevice *))propertyChange
{
 AVCaptureDevice *captureDevice = [self.captureDeviceInput device];
 NSError *error;
 //注意改變設(shè)備屬性前一定要首先調(diào)用lockForConfiguration:調(diào)用完之后使用unlockForConfiguration方法解鎖
 if ([captureDevice lockForConfiguration:&error]) {
  propertyChange(captureDevice);
  [captureDevice unlockForConfiguration];
  
 }else {
  NSLog(@"設(shè)置設(shè)備屬性過程發(fā)生錯誤，錯誤信息：%@", error.localizedDescription);
 }
}
 
//設(shè)置閃光燈模式
- (void)setFlashMode:(AVCaptureFlashMode)flashMode
{
 [self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
  if ([captureDevice isFlashModeSupported:flashMode]) {
   [captureDevice setFlashMode:flashMode];
  }
 }];
}
 
//設(shè)置聚焦模式
- (void)setFocusMode:(AVCaptureFocusMode)focusMode
{
 [self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
  if ([captureDevice isFocusModeSupported:focusMode]) {
   [captureDevice setFocusMode:focusMode];
  }
 }];
}
 
//設(shè)置曝光模式
- (void)setExposureMode:(AVCaptureExposureMode)exposureMode
{
 [self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
  if ([captureDevice isExposureModeSupported:exposureMode]) {
   [captureDevice setExposureMode:exposureMode];
  }
 }];
}
 
//設(shè)置聚焦點
- (void)focusWithMode:(AVCaptureFocusMode)focusMode exposureMode:(AVCaptureExposureMode)exposureMode atPoint:(CGPoint)point
{
 [self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
  if ([captureDevice isFocusModeSupported:focusMode]) {
   [captureDevice setFocusMode:AVCaptureFocusModeAutoFocus];
  }
  if ([captureDevice isFocusPointOfInterestSupported]) {
   [captureDevice setFocusPointOfInterest:point];
  }
  if ([captureDevice isExposureModeSupported:exposureMode]) {
   [captureDevice setExposureMode:AVCaptureExposureModeAutoExpose];
  }
  if ([captureDevice isExposurePointOfInterestSupported]) {
   [captureDevice setExposurePointOfInterest:point];
  }
 }];
}
 
//添加點按手勢，點按時聚焦
- (void)addGenstureRecognizer
{
 [self.containerView addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapScreen:)]];
}
 
- (void)tapScreen:(UITapGestureRecognizer *)tapGesture
{
 CGPoint point = [tapGesture locationInView:self.containerView];
 //將UI坐標(biāo)轉(zhuǎn)化為攝像頭坐標(biāo)
 CGPoint cameraPoint = [self.captureVideoPreviewLayer captureDevicePointOfInterestForPoint:point];
 [self setFocusCursorWithPoint:point];
 [self focusWithMode:AVCaptureFocusModeAutoFocus exposureMode:AVCaptureExposureModeAutoExpose atPoint:cameraPoint];
}
 
//設(shè)置聚焦光標(biāo)位置
- (void)setFocusCursorWithPoint:(CGPoint)point
{
 self.focusCursor.center = point;
 self.focusCursor.transform = CGAffineTransformMakeScale(1.5, 1.5);
 self.focusCursor.alpha = 1.0;
 [UIView animateWithDuration:1.0 animations:^{
  self.focusCursor.transform = CGAffineTransformIdentity;
 } completion:^(BOOL finished) {
  self.focusCursor.alpha = 0;
 }];
}
 
- (void)dealloc
{
 [self removeNotification];
}
 
@end