//
//  RAQRCodeScannerViewController.m
//  Apex And Drivers
//
//  Created by Jack on 2018/6/5.
//  Copyright © 2018年 USAI. All rights reserved.
//

#import "RAQRCodeScannerViewController.h"
#import <AVKit/AVKit.h>

@interface RAQRCodeScannerViewController () <AVCaptureMetadataOutputObjectsDelegate>

@property (strong, nonatomic) IBOutlet UIView *scanerView;
@property (nonatomic,strong) IBOutlet UIView *previewContainer;

@property (nonatomic,strong) AVCaptureDevice *device;
@property (nonatomic,strong) AVCaptureDeviceInput *input;
@property (nonatomic,strong) AVCaptureMetadataOutput *output;
@property (nonatomic,strong) AVCaptureSession *session;
@property (nonatomic,strong) AVCaptureVideoPreviewLayer *previewLayer;

@property (nonatomic,assign) BOOL scannerEnable;
@property (nonatomic,assign) BOOL scannerInitial;

@property (nonatomic,strong) CAGradientLayer *scanLineLayer;

@end

@implementation RAQRCodeScannerViewController

+ (instancetype)viewControllerFromStoryboard {
    RAQRCodeScannerViewController *scannerVC = [[UIStoryboard storyboardWithName:@"QRCode" bundle:nil] instantiateViewControllerWithIdentifier:[self storyboardID]];
    return scannerVC;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    self.scanerView.layer.borderColor = [UIColor blackColor].CGColor;
    self.scanerView.layer.borderWidth = 0.5f;
    
    [self initCapture];
}

- (void)viewDidLayoutSubviews {
    [super viewDidLayoutSubviews];
    
    self.previewLayer.frame = self.view.bounds;
    
    CGFloat w = CGRectGetWidth(self.view.bounds);
    CGFloat h = CGRectGetHeight(self.view.bounds);
    
    /**
     rectOfInterest 都是按照横屏来计算的 所以当竖屏的情况下 x轴和y轴要交换一下
     否则在竖屏下不能扫描条形码。
     */
    CGRect rect = CGRectMake(CGRectGetMinY(self.scanerView.frame) / h, CGRectGetMinX(self.scanerView.frame) / w, CGRectGetHeight(self.scanerView.frame) / h, CGRectGetWidth(self.scanerView.frame) / w);
    
    [self.output setRectOfInterest:rect];
    
    [self.view bringSubviewToFront:self.scanerView];
    
    CGRect scanlineFrame = CGRectMake(0, CGRectGetMidY(self.scanerView.bounds) - 0.5, CGRectGetWidth(self.scanerView.bounds), 1);
    self.scanLineLayer.frame = scanlineFrame;
    [self.scanerView.layer insertSublayer:self.scanLineLayer atIndex:0];
}

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
    
    if (self.scannerInitial) {
        [self.session startRunning];
    }
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    
    if ([self.session isRunning]) {
        [self.session stopRunning];
    }
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (CAGradientLayer *)scanLineLayer {
    if (!_scanLineLayer) {
        CAGradientLayer *gradientLayer = [CAGradientLayer layer];
        //set gradient colors
        // 数组成员接受 CGColorRef 类型的值
        gradientLayer.colors = @[(__bridge id)[UIColor colorWithRed:1 green:0 blue:0 alpha:0.2].CGColor,(__bridge id)[UIColor redColor].CGColor,(__bridge id)[UIColor colorWithRed:1 green:0 blue:0 alpha:0.2].CGColor];
        
        gradientLayer.locations = @[@2.5,@0.5,@0.75];

        gradientLayer.startPoint = CGPointMake(0, 0);
        gradientLayer.endPoint = CGPointMake(1, 0);
        _scanLineLayer = gradientLayer;
    }
    return _scanLineLayer;
}

#pragma mark - Init

- (void)initCapture {
    
    self.scannerInitial = NO;
    self.device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    
    NSError *inputError;
    self.input = [AVCaptureDeviceInput deviceInputWithDevice:self.device error:&inputError];
    
    if (inputError) {
        NSLog(@"init scanner input error: %@",inputError);
        return;
    }
    
    self.session = [[AVCaptureSession alloc] init];
    [self.session setSessionPreset:AVCaptureSessionPresetHigh];
    if ([self.session canAddInput:self.input]) {
        [self.session addInput:self.input];
    } else {
        NSLog(@"init scanner can't add input");
        return;
    }
    
    self.output = [[AVCaptureMetadataOutput alloc] init];
    [self.output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
    
    if ([self.session canAddOutput:self.output]) {
        [self.session addOutput:self.output];
    } else {
        NSLog(@"init scanner can't add output");
        return;
    }
    self.output.metadataObjectTypes = @[
                                        AVMetadataObjectTypeQRCode,
                                        AVMetadataObjectTypeEAN13Code,
                                        AVMetadataObjectTypeEAN8Code,
                                        AVMetadataObjectTypeUPCECode,
                                        AVMetadataObjectTypeCode39Code,
                                        AVMetadataObjectTypeCode39Mod43Code,
                                        AVMetadataObjectTypeCode93Code,
                                        AVMetadataObjectTypeCode128Code,
                                        AVMetadataObjectTypePDF417Code
                                        ];
    
    self.previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:self.session];
    self.previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
    [self.previewContainer.layer addSublayer:self.previewLayer];
    
    self.scannerInitial = YES;
}

#pragma mark - AVCaptureMetadataOutputObjectsDelegate

- (void)captureOutput:(AVCaptureOutput *)output didOutputMetadataObjects:(NSArray<__kindof AVMetadataObject *> *)metadataObjects fromConnection:(AVCaptureConnection *)connection {
    
    if (!self.scannerEnable) {
        return;
    }
    
    if ([metadataObjects count] > 0) {
        [self.session stopRunning];
        
        AVMetadataMachineReadableCodeObject *metadataObject = [metadataObjects objectAtIndex:0];
        NSString *codeValue = metadataObject.stringValue;
        if (self.completion) {
            self.completion(codeValue);
        }
        [self.navigationController popViewControllerAnimated:YES];
    }
    
}

#pragma mark - Action

- (IBAction)scannerBtnTouchDown:(UIButton *)sender {
    self.scannerEnable = YES;
}

- (IBAction)scannerBtnTouchUp:(UIButton *)sender {
    self.scannerEnable = NO;
}

- (IBAction)scannerBtnTouchUpOutSide:(UIButton *)sender {
    self.scannerEnable = NO;
}

- (IBAction)scannerBtnTouchCancel:(UIButton *)sender {
    self.scannerEnable = NO;
}

@end