//

// DYQRCodeDecoderViewController.m

// QRCode-Decoder

//

// Created by Dwarven on 16/7/5.

// Copyright © 2016 Dwarven. All rights reserved.

//

#import "DYQRCodeDecoderViewController.h"

#import <AVFoundation/AVFoundation.h>

#define SCREEN_WIDTH [[UIScreen mainScreen] bounds].size.width

#define SCREEN_HEIGHT [[UIScreen mainScreen] bounds].size.height

@interface DYQRCodeDecoderViewController () <

AVCaptureMetadataOutputObjectsDelegate,

UINavigationControllerDelegate,

UIImagePickerControllerDelegate> {

void(^_completion)(BOOL, NSString *);

NSMutableArray *_observers;

UIView *_viewPreview;

UIImageView * _lineImageView;

CGRect _lineRect0;

CGRect _lineRect1;

}

@property (nonatomic, strong, readwrite) UIBarButtonItem * leftBarButtonItem;

@property (nonatomic, strong, readwrite) UIBarButtonItem * rightBarButtonItem;

@property (nonatomic, strong) UIImagePickerController *imagePicker;

@property (nonatomic, strong) AVCaptureSession *captureSession;

@property (nonatomic, strong) AVCaptureVideoPreviewLayer *videoPreviewLayer;

@property (nonatomic) BOOL isReading;

@end

@implementation DYQRCodeDecoderViewController

- (void)dealloc{

[self cleanNotifications];

_observers = nil;

_viewPreview = nil;

_lineImageView = nil;

_completion = NULL;

self.imagePicker = nil;

self.captureSession = nil;

self.videoPreviewLayer = nil;

self.leftBarButtonItem = nil;

self.rightBarButtonItem = nil;

self.frameImage = nil;

self.lineImage = nil;

self.navigationBarTintColor = nil;

}

- (void)setupNotifications{

if (!_observers) {

_observers = [NSMutableArray array];

}

NSNotificationCenter * center = [NSNotificationCenter defaultCenter];

__weak DYQRCodeDecoderViewController * SELF = self;

id o;

o = [center addObserverForName:UIApplicationDidEnterBackgroundNotification

object:nil

queue:nil

usingBlock:^(NSNotification *note) {

[SELF.imagePicker dismissViewControllerAnimated:NO completion:NULL];

[SELF cancel];

}];

[_observers addObject:o];

}

- (void)cleanNotifications{

for (id o in _observers) {

[[NSNotificationCenter defaultCenter] removeObserver:o];

}

[_observers removeAllObjects];

}

- (id)initWithCompletion:(void (^)(BOOL, NSString *))completion{

self = [super init];

if (self) {

_needsScanAnnimation = YES;

_completion = completion;

_frameImage = [UIImage imageNamed:@"img_animation_scan_pic" inBundle:[NSBundle bundleForClass:[DYQRCodeDecoderViewController class]] compatibleWithTraitCollection:nil];

_lineImage = [UIImage imageNamed:@"img_animation_scan_line" inBundle:[NSBundle bundleForClass:[DYQRCodeDecoderViewController class]] compatibleWithTraitCollection:nil];

_leftBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Cancel"

style:UIBarButtonItemStylePlain

target:self

action:@selector(cancel)];

_rightBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Album"

style:UIBarButtonItemStylePlain

target:self

action:@selector(pickImage)];

}

return self;

}

- (void)viewDidLayoutSubviews{

[super viewDidLayoutSubviews];

[self startReading];

}

- (void)viewWillAppear:(BOOL)animated{

[super viewWillAppear:animated];

if (_needsScanAnnimation) {

[UIView animateWithDuration:2 delay:0 options:UIViewAnimationOptionRepeat animations:^{

[_lineImageView setFrame:_lineRect1];

} completion:^(BOOL finished) {

[_lineImageView setFrame:_lineRect0];

}];

}

}

- (void)viewDidAppear:(BOOL)animated{

[super viewDidAppear:animated];

[self startReading];

}

- (void)viewWillDisappear:(BOOL)animated{

[super viewWillDisappear:animated];

[self stopReading];

}

- (void)viewDidLoad {

[super viewDidLoad];

[self setupNotifications];

_imagePicker = [[UIImagePickerController alloc] init];

_imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

_imagePicker.delegate = self;

if (_navigationBarTintColor) {

if (self.navigationController) {

self.navigationController.navigationBar.tintColor = _navigationBarTintColor;

}

_imagePicker.navigationBar.tintColor =_navigationBarTintColor;

}

// Initially make the captureSession object nil.

_captureSession = nil;

// Set the initial value of the flag to NO.

_isReading = NO;

[self.navigationItem setLeftBarButtonItem:_leftBarButtonItem];

[self.navigationItem setRightBarButtonItem:_rightBarButtonItem];

_viewPreview = [[UIView alloc] init];

[self.view addSubview:_viewPreview];

[_viewPreview setTranslatesAutoresizingMaskIntoConstraints:NO];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_viewPreview

attribute:NSLayoutAttributeTop

relatedBy:NSLayoutRelationEqual

toItem:self.view

attribute:NSLayoutAttributeTop

multiplier:1.0

constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_viewPreview

attribute:NSLayoutAttributeBottom

relatedBy:NSLayoutRelationEqual

toItem:self.view

attribute:NSLayoutAttributeBottom

multiplier:1.0

constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_viewPreview

attribute:NSLayoutAttributeLeft

relatedBy:NSLayoutRelationEqual

toItem:self.view

attribute:NSLayoutAttributeLeft

multiplier:1.0

constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_viewPreview

attribute:NSLayoutAttributeRight

relatedBy:NSLayoutRelationEqual

toItem:self.view

attribute:NSLayoutAttributeRight

multiplier:1.0

constant:0.0]];

if (_needsScanAnnimation) {

UIView * scanView = [[UIView alloc] init];

[scanView setBackgroundColor:[UIColor colorWithWhite:0 alpha:0.7]];

[self.view addSubview:scanView];

[scanView setTranslatesAutoresizingMaskIntoConstraints:NO];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:scanView

attribute:NSLayoutAttributeTop

relatedBy:NSLayoutRelationEqual

toItem:_viewPreview

attribute:NSLayoutAttributeTop

multiplier:1.0

constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:scanView

attribute:NSLayoutAttributeBottom

relatedBy:NSLayoutRelationEqual

toItem:_viewPreview

attribute:NSLayoutAttributeBottom

multiplier:1.0

constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:scanView

attribute:NSLayoutAttributeLeft

relatedBy:NSLayoutRelationEqual

toItem:_viewPreview

attribute:NSLayoutAttributeLeft

multiplier:1.0

constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:scanView

attribute:NSLayoutAttributeRight

relatedBy:NSLayoutRelationEqual

toItem:_viewPreview

attribute:NSLayoutAttributeRight

multiplier:1.0

constant:0.0]];

CGFloat frameWidth = SCREEN_WIDTH * 2 / 3;

//create path

UIBezierPath *path = [UIBezierPath bezierPathWithRect:CGRectMake(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT)];

[path appendPath:[[UIBezierPath bezierPathWithRoundedRect:CGRectMake(SCREEN_WIDTH / 6, SCREEN_HEIGHT / 2 - SCREEN_WIDTH / 3, frameWidth, frameWidth) cornerRadius:0] bezierPathByReversingPath]];

CAShapeLayer *shapeLayer = [CAShapeLayer layer];

shapeLayer.path = path.CGPath;

[scanView.layer setMask:shapeLayer];

UIImageView * imageView = [[UIImageView alloc] init];

[imageView setBackgroundColor:[UIColor clearColor]];

[imageView setImage:_frameImage];

[self.view addSubview:imageView];

[imageView setTranslatesAutoresizingMaskIntoConstraints:NO];

[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:[NSString stringWithFormat:@"V:[imageView(==%f)]", frameWidth]

options:0

metrics:0

views:@{@"imageView":imageView}]];

[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:[NSString stringWithFormat:@"H:[imageView(==%f)]", frameWidth]

options:0

metrics:0

views:@{@"imageView":imageView}]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView

attribute:NSLayoutAttributeCenterX

relatedBy:NSLayoutRelationEqual

toItem:_viewPreview

attribute:NSLayoutAttributeCenterX

multiplier:1.0

constant:0.0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView

attribute:NSLayoutAttributeCenterY

relatedBy:NSLayoutRelationEqual

toItem:_viewPreview

attribute:NSLayoutAttributeCenterY

multiplier:1.0

constant:0.0]];

_lineImageView = [[UIImageView alloc] init];

CGFloat lineHeight = frameWidth * _lineImage.size.height / _lineImage.size.width;

_lineRect0 = CGRectMake(0, 0, frameWidth, lineHeight);

_lineRect1 = CGRectMake(0, frameWidth - lineHeight, frameWidth, lineHeight);

[_lineImageView setFrame:_lineRect0];

[_lineImageView setImage:_lineImage];

[imageView addSubview:_lineImageView];

}

}

- (void)cancel{

[self dismissViewControllerAnimated:NO completion:NULL];

}

- (void)pickImage{

[self presentViewController:_imagePicker animated:YES completion:NULL];

}

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(NSDictionary *)editingInfo {

[picker dismissViewControllerAnimated:NO completion:NULL];

CIContext *context = [CIContext contextWithOptions:nil];

CIDetector *detector = [CIDetector detectorOfType:CIDetectorTypeQRCode

context:context

options:@{CIDetectorAccuracy:CIDetectorAccuracyHigh}];

CIImage *cgImage = [CIImage imageWithCGImage:image.CGImage];

NSArray *features = [detector featuresInImage:cgImage];

CIQRCodeFeature *feature = [features firstObject];

NSString *result = feature.messageString;

if (_completion) {

_completion(result != nil, result);

}

[self dealWithResult:result];

[self cancel];

}

- (void)start {

[self startReading];

}

- (void)stop {

[self stopReading];

}

- (void)dealWithResult:(NSString *)result {

}

#pragma mark - Private method implementation

- (void)startReading {

if (!_isReading) {

NSError *error;

// Get an instance of the AVCaptureDevice class to initialize a device object and provide the video

// as the media type parameter.

AVCaptureDevice *captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

// Get an instance of the AVCaptureDeviceInput class using the previous device object.

AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&error];

if (input) {

// Initialize the captureSession object.

_captureSession = [[AVCaptureSession alloc] init];

// Set the input device on the capture session.

[_captureSession addInput:input];

// Initialize a AVCaptureMetadataOutput object and set it as the output device to the capture session.

AVCaptureMetadataOutput *captureMetadataOutput = [[AVCaptureMetadataOutput alloc] init];

[_captureSession addOutput:captureMetadataOutput];

// Create a new serial dispatch queue.

dispatch_queue_t dispatchQueue;

dispatchQueue = dispatch_queue_create("myQueue", NULL);

[captureMetadataOutput setMetadataObjectsDelegate:self queue:dispatchQueue];

[captureMetadataOutput setMetadataObjectTypes:[NSArray arrayWithObject:AVMetadataObjectTypeQRCode]];

// Initialize the video preview layer and add it as a sublayer to the viewPreview view's layer.

_videoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:_captureSession];

[_videoPreviewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];

[_videoPreviewLayer setFrame:_viewPreview.layer.bounds];

[_viewPreview.layer addSublayer:_videoPreviewLayer];

// Start video capture.

[_captureSession startRunning];

_isReading = !_isReading;

} else {

// If any error occurs, simply log the description of it and don't continue any more.

NSLog(@"%@", [error localizedDescription]);

return;

}

}

}

- (void)stopReading {

if (_isReading) {

// Stop video capture and make the capture session object nil.

[_captureSession stopRunning];

_captureSession = nil;

// Remove the video preview layer from the viewPreview view's layer.

[_videoPreviewLayer removeFromSuperlayer];

_isReading = !_isReading;

}

}

- (void)didReceiveMemoryWarning {

[super didReceiveMemoryWarning];

}

#pragma mark - AVCaptureMetadataOutputObjectsDelegate method implementation

-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{

// Check if the metadataObjects array is not nil and it contains at least one object.

if (metadataObjects != nil && [metadataObjects count] > 0) {

// Get the metadata object.

AVMetadataMachineReadableCodeObject *metadataObj = [metadataObjects objectAtIndex:0];

if ([[metadataObj type] isEqualToString:AVMetadataObjectTypeQRCode]) {

// If the found metadata is equal to the QR code metadata then update the status label's text,

// stop reading and change the bar button item's title and the flag's value.

// Everything is done on the main thread.

void(^block)() = ^(void) {

[self stopReading];

[self cancel];

if (![metadataObj stringValue] || [[metadataObj stringValue] length] == 0) {

if (_completion) {

_completion(NO, nil);

}

[self dealWithResult:nil];

} else {

if (_completion) {

_completion(YES, [metadataObj stringValue]);

}

[self dealWithResult:[metadataObj stringValue]];

}

};

if ([NSThread isMainThread]) {

block();

} else {

dispatch_sync(dispatch_get_main_queue(), ^{

block();

});

}

}

}

}

@end