ResearchKit/ResearchKitActiveTask/Stroop/ORKAccuracyStroopStepViewController.m

/*
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 may be used to endorse or promote products derived from this software without
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#import "ORKAccuracyStroopStepViewController.h"
#import "ORKAccuracyStroopStep.h"
#import "ORKAccuracyStroopResult.h"

#import "ORKCollectionResult.h"
#import "ORKHelpers_Internal.h"
#import "ORKStepViewController_Internal.h"
#import "UIColor+String.h"

@interface ORKAccuracyStroopStepViewController () <UIGestureRecognizerDelegate>

@property (nonatomic) NSMutableArray <UIView *> *circles;
@property (nonatomic, strong) UILabel *colorLabel;
@property (nonatomic) UIView *circlesView;
@property (nonatomic) NSArray<NSLayoutConstraint *> *constraints;
@property (nonatomic) double distanceToClosestCenter;
@property (nonatomic) UIColor *selectedColor;

@end

@implementation ORKAccuracyStroopStepViewController

- (ORKAccuracyStroopStep *)accuracyStroopStep {
    return (ORKAccuracyStroopStep *)self.step;
}

- (void)stepDidChange {
    [super stepDidChange];
    
    if (self.step && [self isViewLoaded]) {
        [self setupColorLabel];
        [self setupCirclesView];
        [self setupConstraints];
        
        dispatch_async(dispatch_get_main_queue(), ^{
            [self setupCircles];
            [self setupViewTap];
        });
    }
}

- (void)setupViewTap {
    for (UIGestureRecognizer *recognizer in self.circlesView.gestureRecognizers) {
        [self.circlesView removeGestureRecognizer:recognizer];
    }
    
    UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTap:)];
    tapGestureRecognizer.delegate = self;
    [self.circlesView addGestureRecognizer:tapGestureRecognizer];
}

- (void)setupCirclesView {
    [self.circlesView removeFromSuperview];
    self.circlesView = nil;
    
    self.circlesView = UIView.new;
    [self.view addSubview:self.circlesView];
}

- (void)setupColorLabel {
    [self.colorLabel removeFromSuperview];
    self.colorLabel = nil;
    
    self.colorLabel = UILabel.new;
    self.colorLabel.text = self.accuracyStroopStep.actualDisplayColor.textRepresentation;
    self.colorLabel.textColor = self.accuracyStroopStep.baseDisplayColor;
    self.colorLabel.font = [UIFont systemFontOfSize:35.0 weight:UIFontWeightMedium];
    [self.view addSubview:self.colorLabel];
}

- (void)setupConstraints {
    if (self.constraints) {
        [NSLayoutConstraint deactivateConstraints:self.constraints];
    }
    self.colorLabel.translatesAutoresizingMaskIntoConstraints = NO;
    self.circlesView.translatesAutoresizingMaskIntoConstraints = NO;
    self.constraints = nil;
    self.constraints = @[
        [NSLayoutConstraint constraintWithItem:self.colorLabel
                                     attribute:NSLayoutAttributeTop
                                     relatedBy:NSLayoutRelationEqual
                                        toItem:self.view
                                     attribute:NSLayoutAttributeTop
                                    multiplier:1.0
                                      constant:10.0],
        [NSLayoutConstraint constraintWithItem:self.colorLabel
                                     attribute:NSLayoutAttributeCenterX
                                     relatedBy:NSLayoutRelationEqual
                                        toItem:self.view
                                     attribute:NSLayoutAttributeCenterX
                                    multiplier:1.0
                                      constant:0.0],
        [NSLayoutConstraint constraintWithItem:self.circlesView
                                     attribute:NSLayoutAttributeTop
                                     relatedBy:NSLayoutRelationEqual
                                        toItem:self.colorLabel
                                     attribute:NSLayoutAttributeBottom
                                    multiplier:1.0
                                      constant:0.0],
        [NSLayoutConstraint constraintWithItem:self.circlesView
                                     attribute:NSLayoutAttributeLeading
                                     relatedBy:NSLayoutRelationEqual
                                        toItem:self.view
                                     attribute:NSLayoutAttributeLeading
                                    multiplier:1.0
                                      constant:0.0],
        [NSLayoutConstraint constraintWithItem:self.circlesView
                                     attribute:NSLayoutAttributeTrailing
                                     relatedBy:NSLayoutRelationEqual
                                        toItem:self.view
                                     attribute:NSLayoutAttributeTrailing
                                    multiplier:1.0
                                      constant:0.0],
        [NSLayoutConstraint constraintWithItem:self.circlesView
                                     attribute:NSLayoutAttributeBottom
                                     relatedBy:NSLayoutRelationEqual
                                        toItem:self.view
                                     attribute:NSLayoutAttributeBottom
                                    multiplier:1.0
                                      constant:0.0]
    ];
    [NSLayoutConstraint activateConstraints:self.constraints];
}

- (void)setupCircles {
    for (UIView *circle in self.circles) {
        [circle removeFromSuperview];
    }

    [self.circles removeAllObjects];
    self.circles = NSMutableArray.array;
    
    // Constants to use for ball and grid
    int ballSize = 50;
    int padding = 10;
    int cellSize = ballSize + padding * 2;

    // Calculating number of rows/columns in grid to layout color circles
    uint32_t numRows = (self.circlesView.bounds.size.height) / cellSize;
    uint32_t numColumns = (self.circlesView.bounds.size.width) / cellSize;
    
    // Extra padding to ensure that the grid spans the whole screen width
    int extraHorizontalSpaceForCell = ((int)self.circlesView.bounds.size.width % cellSize) / numColumns;
    
    // Matrix to keep track of cells that already have a circle --> avoid overlap in O(n)
    bool cellTakenMatrix[numRows][numColumns];
    for (uint32_t r = 0; r < numRows; r++) {
        for (uint32_t c = 0; c < numColumns; c++) {
            cellTakenMatrix[r][c] = false;
        }
    }
    
    for (int colorIndex = 0; colorIndex < ORKAccuracyStroopStep.colors.count; colorIndex++) {
        // Obtain random location for color circle within bounds
        int randomR = (int)arc4random_uniform(numRows);
        int randomC = (int)arc4random_uniform(numColumns);

        ORK_Log_Debug("Trying placement for color: %d at (r, c): (%d, %d)", colorIndex, randomR, randomC);
        
        // If cell is already taken, look at 8 spots around for a free spot
        if (cellTakenMatrix[randomR][randomC]) {
            ORK_Log_Debug("Position (r, c): (%d, %d) already taken", randomR, randomC);
            
            // Loops through the 3x3 grid with randomR,randomC as the center
            bool shouldBreak = false;
            for (int r = randomR - 1; !shouldBreak && r <= randomR + 1; r++) {
                for (int c = randomC - 1; !shouldBreak && c <= randomC + 1; c++) {
                    // If r/c are out of circleView's bounds, then don't consider
                    if ((r < 0 || r >= numRows) || (c < 0 || c >= numColumns)) { continue; }
                    
                    // If cell is not taken, then can assign to there and break out of for-loops
                    if (!cellTakenMatrix[r][c]) {
                        randomR = r;
                        randomC = c;
                        shouldBreak = true;
                    }
                }
            }
        }
        
        ORK_Log_Info("Final position for color: %d at (r, c): (%d, %d)", colorIndex, randomR, randomC);

        cellTakenMatrix[randomR][randomC] = true;
        
        CGFloat circleX = (randomC * (cellSize + extraHorizontalSpaceForCell)) + padding + extraHorizontalSpaceForCell / 2;
        CGFloat circleY = (randomR * cellSize) + padding;
        CGRect frame = CGRectMake(circleX, circleY, ballSize, ballSize);
        UIView *newCircle = [[UIView alloc] initWithFrame:frame];
        newCircle.backgroundColor = ORKAccuracyStroopStep.colors[colorIndex];
        newCircle.clipsToBounds = YES;
        newCircle.layer.cornerRadius = ballSize / 2;
        newCircle.tag = colorIndex;
        [self.circles addObject:newCircle];
        [self.circlesView addSubview:newCircle];
    }
}

- (void)handleTap:(UITapGestureRecognizer *)recognizer {
    CGPoint touchPoint = [recognizer locationInView:self.circlesView];
    double minDistance = INFINITY;
        
    for (UIView *circle in self.circles) {
        double dx = (touchPoint.x - circle.center.x);
        double dy = (touchPoint.y - circle.center.y);
        double distance = sqrt(dx * dx + dy * dy);
        if (distance < minDistance) {
            minDistance = distance;
        }
        
        if (CGRectContainsPoint(circle.frame, touchPoint)) {
            self.selectedColor = ORKAccuracyStroopStep.colors[circle.tag];
            self.distanceToClosestCenter = distance;
            [super goForward];
            return;
        }
    }
    
    self.distanceToClosestCenter = minDistance;
    [super goForward];
}

- (BOOL)hasPreviousStep {
    return NO;
}

- (ORKStepResult *)result {
    ORKStepResult *stepResult = [super result];
    
    ORKAccuracyStroopResult *result = [[ORKAccuracyStroopResult alloc] initWithIdentifier:self.accuracyStroopStep.identifier];
    result.color = self.accuracyStroopStep.baseDisplayColor.textRepresentation;
    result.colorSelected = self.selectedColor.textRepresentation;
    result.distanceToClosestCenter = self.distanceToClosestCenter;
    result.startDate = stepResult.startDate;
    result.endDate = stepResult.endDate;
    result.timeTakenToSelect = [result.endDate timeIntervalSinceDate:result.startDate];

    NSMutableArray *results = [[NSMutableArray alloc] init];
    if (stepResult.results) {
        results = [stepResult.results mutableCopy];
    }
    
    [results addObject:result];
    
    stepResult.results = [results copy];
    return stepResult;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    [self stepDidChange];
}

@end