keyboard/keyBoard/Class/Login/VC/KBLoginSheetViewController.m

//
//  KBLoginSheetViewController.m
//  keyBoard
//
//  Bottom sheet asking user to login with Apple ID. Tapping Continue shows LoginViewController.
//

#import "KBLoginSheetViewController.h"
#import "LoginViewController.h"
#import <Masonry/Masonry.h>

@interface KBLoginSheetViewController ()
@property (nonatomic, strong) UIControl *backdrop;
@property (nonatomic, strong) UIView *sheet;
@property (nonatomic, strong) UIButton *checkButton;
@property (nonatomic, strong) UILabel *descLabel;
@property (nonatomic, strong) UIButton *continueButton;
@end

@implementation KBLoginSheetViewController

+ (void)presentIfNeededFrom:(UIViewController *)presenting {
    if (!presenting) return;
    // 避免重复弹多个
    if ([presenting.presentedViewController isKindOfClass:[self class]]) return;
    KBLoginSheetViewController *vc = [KBLoginSheetViewController new];
    vc.modalPresentationStyle = UIModalPresentationOverFullScreen;
    [presenting presentViewController:vc animated:NO completion:nil];
}

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor clearColor];
    [self buildUI];
}

- (void)buildUI {
    self.backdrop = [[UIControl alloc] init];
    self.backdrop.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.15];
    [self.backdrop addTarget:self action:@selector(dismissSelf) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:self.backdrop];
    [self.backdrop mas_makeConstraints:^(MASConstraintMaker *make) {
        make.edges.equalTo(self.view);
    }];

    self.sheet = [[UIView alloc] init];
    self.sheet.backgroundColor = [UIColor whiteColor];
    self.sheet.layer.cornerRadius = 12.0;
    self.sheet.layer.masksToBounds = YES;
    [self.view addSubview:self.sheet];
    [self.sheet mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.right.equalTo(self.view);
        make.bottom.equalTo(self.view.mas_safeAreaLayoutGuideBottom);
        make.height.mas_equalTo(160);
    }];

    self.checkButton = [UIButton buttonWithType:UIButtonTypeSystem];
    self.checkButton.layer.cornerRadius = 16;
    self.checkButton.layer.borderWidth = 2;
    self.checkButton.layer.borderColor = [UIColor colorWithWhite:0.8 alpha:1.0].CGColor;
    self.checkButton.backgroundColor = [UIColor whiteColor];
    [self.checkButton setTitle:@"" forState:UIControlStateNormal];
    [self.checkButton addTarget:self action:@selector(toggleCheck) forControlEvents:UIControlEventTouchUpInside];

    self.descLabel = [UILabel new];
    self.descLabel.text = @"allow log in with apple id?";
    self.descLabel.textColor = [UIColor blackColor];
    self.descLabel.font = [UIFont systemFontOfSize:16];

    [self.sheet addSubview:self.checkButton];
    [self.sheet addSubview:self.descLabel];
    [self.checkButton mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.equalTo(self.sheet).offset(28);
        make.top.equalTo(self.sheet).offset(18);
        make.width.height.mas_equalTo(32);
    }];
    [self.descLabel mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.equalTo(self.checkButton.mas_right).offset(12);
        make.centerY.equalTo(self.checkButton.mas_centerY);
        make.right.lessThanOrEqualTo(self.sheet).offset(-20);
    }];

    self.continueButton = [UIButton buttonWithType:UIButtonTypeSystem];
    self.continueButton.backgroundColor = [UIColor whiteColor];
    self.continueButton.layer.cornerRadius = 10;
    self.continueButton.layer.borderWidth = 1.0;
    self.continueButton.layer.borderColor = [UIColor colorWithWhite:0.8 alpha:1.0].CGColor;
    [self.continueButton setTitle:@"Continue" forState:UIControlStateNormal];
    [self.continueButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    self.continueButton.titleLabel.font = [UIFont boldSystemFontOfSize:20];
    [self.continueButton addTarget:self action:@selector(onContinue) forControlEvents:UIControlEventTouchUpInside];
    [self.sheet addSubview:self.continueButton];
    [self.continueButton mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.equalTo(self.sheet).offset(28);
        make.right.equalTo(self.sheet).offset(-28);
        make.height.mas_equalTo(48);
        make.top.equalTo(self.checkButton.mas_bottom).offset(18);
    }];
}

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
    // 初始位置在屏幕下方，做一个上滑动画
    CGRect frame = self.sheet.frame;
    self.sheet.transform = CGAffineTransformMakeTranslation(0, frame.size.height + 40);
    self.backdrop.alpha = 0;
    [UIView animateWithDuration:0.22 animations:^{
        self.sheet.transform = CGAffineTransformIdentity;
        self.backdrop.alpha = 1;
    }];
}

- (void)dismissSelf {
    [UIView animateWithDuration:0.18 animations:^{
        self.sheet.transform = CGAffineTransformMakeTranslation(0, self.sheet.bounds.size.height + 40);
        self.backdrop.alpha = 0;
    } completion:^(BOOL finished) {
        [self dismissViewControllerAnimated:NO completion:nil];
    }];
}

- (void)toggleCheck {
    self.checkButton.selected = !self.checkButton.selected;
    if (self.checkButton.selected) {
        self.checkButton.backgroundColor = [UIColor colorWithRed:0.22 green:0.49 blue:0.96 alpha:1.0];
        self.checkButton.layer.borderColor = self.checkButton.backgroundColor.CGColor;
    } else {
        self.checkButton.backgroundColor = [UIColor whiteColor];
        self.checkButton.layer.borderColor = [UIColor colorWithWhite:0.8 alpha:1.0].CGColor;
    }
}

- (void)onContinue {
    LoginViewController *login = [LoginViewController new];
    __weak typeof(self) weakSelf = self;
    login.onLoginSuccess = ^(NSDictionary * _Nonnull userInfo) {
        __strong typeof(weakSelf) self = weakSelf; if (!self) return;
        [self dismissViewControllerAnimated:YES completion:^{
            if (self.onLoginSuccess) self.onLoginSuccess();
            [self dismissSelf];
        }];
    };
    login.modalPresentationStyle = UIModalPresentationPageSheet;
    [self presentViewController:login animated:YES completion:nil];
}

@end