/*

 Copyright (C) 2014 Apple Inc. All Rights Reserved.

 See LICENSE.txt for this sample’s licensing information

 Abstract:

  The profile view controller in the application.  Allows users to view, edit, and preview their profile.

 */

#import "AAPLProfileViewController.h"

#import "AAPLStyleUtilities.h"

#import "AAPLCardView.h"

#import "AAPLPerson.h"

#import "AAPLAgeSlider.h"

#import "AAPLPreviewLabel.h"

static const CGFloat AAPLLabelControlMinimumSpacing = 20.0;

static const CGFloat AAPLMinimumVerticalSpacingBetweenRows = 20.0;

static const CGFloat AAPLPreviewTabMinimumWidth = 80.0;

static const CGFloat AAPLPreviewTabHeight = 30.0;

static const CGFloat AAPLPreviewTabCornerRadius = 10.0;

static const CGFloat AAPLPreviewTabHorizontalPadding = 30.0;

static const NSTimeInterval AAPLCardRevealAnimationDuration = 0.3;

@interface AAPLProfileViewController () <UITextFieldDelegate, AAPLPreviewLabelDelegate>

@property (nonatomic) AAPLPerson *person;

@property (nonatomic) UILabel *ageValueLabel;

@property (nonatomic) UITextField *hobbiesField;

@property (nonatomic) UITextField *elevatorPitchField;

@property (nonatomic) UIImageView *previewTab;

@property (nonatomic) AAPLCardView *cardView;

@property (nonatomic) NSLayoutConstraint *cardRevealConstraint;

@property (nonatomic) BOOL cardWasRevealedBeforePan;

@end

@implementation AAPLProfileViewController

- (instancetype)init {

    self = [super init];

    if (self) {

        self.title = NSLocalizedString(@"Profile", @"Title of the profile page");

        self.backgroundImage = [UIImage imageNamed:@"girl-bg"];

        // Create the model.  If we had a backing service, this model would pull data from the user's account settings.

        self.person = [[AAPLPerson alloc] init];

        self.person.photo = [UIImage imageNamed:@"girl"];

        self.person.age = 37;

        self.person.hobbies = @"Music, swing dance, wine";

        self.person.elevatorPitch = @"I can keep a steady beat.";

    }

    return self;

}

#pragma mark - Views and Constraints

- (void)viewDidLoad {

    [super viewDidLoad];

    UIView *containerView = self.view;

    NSMutableArray *constraints = [NSMutableArray array];

    UIView *overlayView = [self addOverlayViewToView:containerView constraints:constraints];

    NSArray *ageControls = [self addAgeControlsToView:overlayView constraints:constraints];

    self.hobbiesField = [self addTextFieldWithName:NSLocalizedString(@"Hobbies", @"The user's hobbies") text:self.person.hobbies toView:overlayView previousRowItems:ageControls constraints:constraints];

    self.elevatorPitchField = [self addTextFieldWithName:NSLocalizedString(@"Elevator Pitch", @"The user's elevator pitch for finding a partner") text:self.person.elevatorPitch toView:overlayView previousRowItems:@[self.hobbiesField] constraints:constraints];

    [self addCardAndPreviewTab:constraints];

    [containerView addConstraints:constraints];

}

- (UIView *)addOverlayViewToView:(UIView *)containerView constraints:(NSMutableArray *)constraints {

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

    overlayView.backgroundColor = [AAPLStyleUtilities overlayColor];

    overlayView.layer.cornerRadius = [AAPLStyleUtilities overlayCornerRadius];

    overlayView.translatesAutoresizingMaskIntoConstraints = NO;

    [containerView addSubview:overlayView];

    // Cover the view controller with the overlay, leaving a margin on all sides

    CGFloat margin = [AAPLStyleUtilities overlayMargin];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:overlayView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:[self topLayoutGuide] attribute:NSLayoutAttributeBottom multiplier:1.0 constant:margin]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:overlayView attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:[self bottomLayoutGuide] attribute:NSLayoutAttributeBottom multiplier:1.0 constant:-margin]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:overlayView attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual toItem:containerView attribute:NSLayoutAttributeLeft multiplier:1.0 constant:margin]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:overlayView attribute:NSLayoutAttributeRight relatedBy:NSLayoutRelationEqual toItem:containerView attribute:NSLayoutAttributeRight multiplier:1.0 constant:-margin]];

    return overlayView;

}

- (void)updateAgeValueLabelFromSlider:(AAPLAgeSlider *)ageSlider {

    self.ageValueLabel.text = [NSNumberFormatter localizedStringFromNumber:@(ageSlider.value) numberStyle:NSNumberFormatterDecimalStyle];

}

- (UILabel *)addAgeValueLabelToView:(UIView *)overlayView {

    UILabel *ageValueLabel = [AAPLStyleUtilities standardLabel];

    ageValueLabel.isAccessibilityElement = NO;

    [overlayView addSubview:ageValueLabel];

    return ageValueLabel;

}

- (NSArray *)addAgeControlsToView:(UIView *)overlayView constraints:(NSMutableArray *)constraints {

    UILabel *ageTitleLabel = [AAPLStyleUtilities standardLabel];

    ageTitleLabel.text = NSLocalizedString(@"Your age", @"The user's age");

    [overlayView addSubview:ageTitleLabel];

    AAPLAgeSlider *ageSlider = [[AAPLAgeSlider alloc] init];

    ageSlider.value = self.person.age;

    [ageSlider addTarget:self action:@selector(didUpdateAge:) forControlEvents:UIControlEventValueChanged];

    ageSlider.translatesAutoresizingMaskIntoConstraints = NO;

    [overlayView addSubview:ageSlider];

    // Display the current age next to the slider

    self.ageValueLabel = [self addAgeValueLabelToView:overlayView];

    [self updateAgeValueLabelFromSlider:ageSlider];

    // Position the age title and value side by side, within the overlay view

    [constraints addObject:[NSLayoutConstraint constraintWithItem:ageTitleLabel attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:overlayView attribute:NSLayoutAttributeTop multiplier:1.0 constant:[AAPLStyleUtilities contentVerticalMargin]]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:ageTitleLabel attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:overlayView attribute:NSLayoutAttributeLeading multiplier:1.0 constant:[AAPLStyleUtilities contentHorizontalMargin]]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:ageSlider attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:ageTitleLabel attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:AAPLLabelControlMinimumSpacing]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:ageSlider attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:ageTitleLabel attribute:NSLayoutAttributeCenterY multiplier:1.0 constant:0.0]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:self.ageValueLabel attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:ageSlider attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:AAPLLabelControlMinimumSpacing]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:self.ageValueLabel attribute:NSLayoutAttributeFirstBaseline relatedBy:NSLayoutRelationEqual toItem:ageTitleLabel attribute:NSLayoutAttributeFirstBaseline multiplier:1.0 constant:0.0]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:self.ageValueLabel attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:overlayView attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:-1 * [AAPLStyleUtilities contentHorizontalMargin]]];

    return @[ageTitleLabel, ageSlider, self.ageValueLabel];

}

- (UITextField *)addTextFieldWithName:(NSString *)name text:(NSString *)text toView:(UIView *)overlayView previousRowItems:(NSArray *)previousRowItems constraints:(NSMutableArray *)constraints {

    UILabel *titleLabel = [AAPLStyleUtilities standardLabel];

    titleLabel.text = name;

    [overlayView addSubview:titleLabel];

    UITextField *valueField = [[UITextField alloc] init];

    valueField.delegate = self;

    valueField.font = [AAPLStyleUtilities standardFont];

    valueField.textColor = [AAPLStyleUtilities detailOnOverlayColor];

    valueField.text = text;

    valueField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:NSLocalizedString(@"Type here...", @"Placeholder for profile text fields") attributes:@{NSForegroundColorAttributeName: [AAPLStyleUtilities detailOnOverlayPlaceholderColor]}];

    valueField.translatesAutoresizingMaskIntoConstraints = NO;

    [overlayView addSubview:valueField];

    // Ensure sufficient spacing from the row above this one

    for (UIView *previousRowItem in previousRowItems) {

            [constraints addObject:[NSLayoutConstraint constraintWithItem:titleLabel attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationGreaterThanOrEqual toItem:previousRowItem attribute:NSLayoutAttributeBottom multiplier:1.0 constant:AAPLMinimumVerticalSpacingBetweenRows]];

    }

    // Place the title directly above the value

    [constraints addObject:[NSLayoutConstraint constraintWithItem:valueField attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:titleLabel attribute:NSLayoutAttributeBottom multiplier:1.0 constant:0.0]];

    // Position the title and value within the overlay view

    [constraints addObject:[NSLayoutConstraint constraintWithItem:titleLabel attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:overlayView attribute:NSLayoutAttributeLeading multiplier:1.0 constant:[AAPLStyleUtilities contentHorizontalMargin]]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:valueField attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:titleLabel attribute:NSLayoutAttributeLeading multiplier:1.0 constant:0.0]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:valueField attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:overlayView attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:-1 * [AAPLStyleUtilities contentHorizontalMargin]]];

    return valueField;

}

- (UIImage *)previewTabBackgroundImage {

    // The preview tab should be flat on the bottom, and have rounded corners on top.

    UIGraphicsBeginImageContextWithOptions(CGSizeMake(AAPLPreviewTabMinimumWidth, AAPLPreviewTabHeight), NO, [[UIScreen mainScreen] scale]);

    UIBezierPath *roundedTopCornersRect = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0.0, 0.0, AAPLPreviewTabMinimumWidth, AAPLPreviewTabHeight) byRoundingCorners:(UIRectCorner)(UIRectCornerTopLeft | UIRectCornerTopRight) cornerRadii:CGSizeMake(AAPLPreviewTabCornerRadius, AAPLPreviewTabCornerRadius)];

    [[AAPLStyleUtilities foregroundColor] set];

    [roundedTopCornersRect fill];

    UIImage *previewTabBackgroundImage = UIGraphicsGetImageFromCurrentImageContext();

    previewTabBackgroundImage = [previewTabBackgroundImage resizableImageWithCapInsets:UIEdgeInsetsMake(0.0, AAPLPreviewTabCornerRadius, 0.0, AAPLPreviewTabCornerRadius)];

    UIGraphicsEndImageContext();

    return previewTabBackgroundImage;

}

- (UIImageView *)addPreviewTab {

    UIImage *previewTabBackgroundImage = [self previewTabBackgroundImage];

    UIImageView *previewTab = [[UIImageView alloc] initWithImage:previewTabBackgroundImage];

    previewTab.userInteractionEnabled = YES;

    [self.view addSubview:previewTab];

    UIPanGestureRecognizer *revealGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(didSlidePreviewTab:)];

    [previewTab addGestureRecognizer:revealGestureRecognizer];

    return previewTab;

}

- (AAPLPreviewLabel *)addPreviewLabel {

    AAPLPreviewLabel *previewLabel = [[AAPLPreviewLabel alloc] init];

    previewLabel.delegate = self;

    [self.view addSubview:previewLabel];

    return previewLabel;

}

- (AAPLCardView *)addCardView {

    AAPLCardView *cardView = [[AAPLCardView alloc] init];

    [cardView updateWithPerson:self.person];

    self.cardView = cardView;

    [self.view addSubview:cardView];

    return cardView;

}

- (void)addCardAndPreviewTab:(NSMutableArray *)constraints {

    self.previewTab = [self addPreviewTab];

    self.previewTab.translatesAutoresizingMaskIntoConstraints = NO;

    AAPLPreviewLabel *previewLabel = [self addPreviewLabel];

    previewLabel.translatesAutoresizingMaskIntoConstraints = NO;

    AAPLCardView *cardView = [self addCardView];

    cardView.translatesAutoresizingMaskIntoConstraints = NO;

    // Pin the tab to the bottom center of the screen

    self.cardRevealConstraint = [NSLayoutConstraint constraintWithItem:self.previewTab attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeBottom multiplier:1.0 constant:0.0];

    [constraints addObject:self.cardRevealConstraint];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:self.previewTab attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0.0]];

    // Center the preview label within the tab

    [constraints addObject:[NSLayoutConstraint constraintWithItem:previewLabel attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:self.previewTab attribute:NSLayoutAttributeLeading multiplier:1.0 constant:AAPLPreviewTabHorizontalPadding]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:previewLabel attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:self.previewTab attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:-AAPLPreviewTabHorizontalPadding]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:previewLabel attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:self.previewTab attribute:NSLayoutAttributeCenterY multiplier:1.0 constant:0.0]];

    // Pin the top of the card to the bottom of the tab

    [constraints addObject:[NSLayoutConstraint constraintWithItem:cardView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:self.previewTab attribute:NSLayoutAttributeBottom multiplier:1.0 constant:0.0]];

    [constraints addObject:[NSLayoutConstraint constraintWithItem:cardView attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:self.previewTab attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0.0]];

    // Ensure that the card fits within the view

    [constraints addObject:[NSLayoutConstraint constraintWithItem:cardView attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationLessThanOrEqual toItem:self.view attribute:NSLayoutAttributeWidth multiplier:1.0 constant:0.0]];

}

#pragma mark - Responding to Actions

- (void)didUpdateAge:(AAPLAgeSlider *)ageSlider {

    // Turn the value into a valid age

    ageSlider.value = round(ageSlider.value);

    // Display the updated age next to the slider

    [self updateAgeValueLabelFromSlider:ageSlider];

    // Update the model

    self.person.age = ageSlider.value;

    // Update the card view with the new data

    [self.cardView updateWithPerson:self.person];

}

- (BOOL)isCardRevealed {

    return (self.cardRevealConstraint.constant < 0.0);

}

- (CGFloat)cardHeight {

    return CGRectGetHeight(self.cardView.frame);

}

- (void)revealCard {

    [self.view layoutIfNeeded];

    [UIView animateWithDuration:AAPLCardRevealAnimationDuration animations:^{

        self.cardRevealConstraint.constant = -1 * [self cardHeight];

        [self.view layoutIfNeeded];

    } completion:^(BOOL finished) {

        UIAccessibilityPostNotification(UIAccessibilityLayoutChangedNotification, nil);

    }];

}

- (void)dismissCard {

    [self.view layoutIfNeeded];

    [UIView animateWithDuration:AAPLCardRevealAnimationDuration animations:^{

        self.cardRevealConstraint.constant = 0.0;

        [self.view layoutIfNeeded];

    } completion:^(BOOL finished) {

        UIAccessibilityPostNotification(UIAccessibilityLayoutChangedNotification, nil);

    }];

}

- (void)didSlidePreviewTab:(UIPanGestureRecognizer *)gestureRecognizer {

    switch (gestureRecognizer.state) {

        case UIGestureRecognizerStateBegan:

            self.cardWasRevealedBeforePan = [self isCardRevealed];

            break;

        case UIGestureRecognizerStateChanged:

        {

            CGFloat cardHeight = [self cardHeight];

            CGFloat cardRevealConstant = [gestureRecognizer translationInView:self.view].y;

            if (self.cardWasRevealedBeforePan) {

                cardRevealConstant += -1 * cardHeight;

            }

            // Never let the card tab move off screen

            cardRevealConstant = MIN(0.0, cardRevealConstant);

            // Never let the card have a gap below it

            cardRevealConstant = MAX(-1 * cardHeight, cardRevealConstant);

            self.cardRevealConstraint.constant = cardRevealConstant;

        }

            break;

        case UIGestureRecognizerStateEnded:

            if (self.cardRevealConstraint.constant > (-0.5 * [self cardHeight])) {

                // Card was closer to the bottom of the screen

                [self dismissCard];

            } else {

                [self revealCard];

            }

            break;

        case UIGestureRecognizerStateCancelled:

            if (self.cardWasRevealedBeforePan) {

                [self revealCard];

            } else {

                [self dismissCard];

            }

            break;

        default:

            break;

    }

}

- (void)doneButtonPressed:(id)sender {

    // End editing on whichever text field is first responder

    [self.hobbiesField resignFirstResponder];

    [self.elevatorPitchField resignFirstResponder];

}

#pragma mark - UITextFieldDelegate

- (void)textFieldDidBeginEditing:(UITextField *)textField {

    // Add a Done button so that the user can dismiss the keyboard easily

    self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(doneButtonPressed:)];

}

- (void)textFieldDidEndEditing:(UITextField *)textField {

    // Remove the Done button

    self.navigationItem.rightBarButtonItem = nil;

    // Update the model

    if (textField == self.hobbiesField) {

        self.person.hobbies = textField.text;

    } else if (textField == self.elevatorPitchField) {

        self.person.elevatorPitch = textField.text;

    }

    // Update the card view with the new data

    [self.cardView updateWithPerson:self.person];

}

#pragma mark - AAPLPreviewLabelDelegate

- (void)didActivatePreviewLabel:(AAPLPreviewLabel *)previewLabel {

    if ([self isCardRevealed]) {

        [self dismissCard];

    } else {

        [self revealCard];

    }

}

@end