//
// CustomPageControl.m
// CustomPageControl


#import "CustomPageControl.h"


#define kDotDiameter 4.0f
#define kDotSpace 12.0f


@implementation CustomPageControl

@synthesize numberOfPages ;
@synthesize currentPage ;
@synthesize hidesForSinglePage ;
@synthesize defersCurrentPageDisplay ;

@synthesize type ;
@synthesize onColor ;
@synthesize offColor ;
@synthesize onImage ;
@synthesize offImage ;

@synthesize indicatorDiameter ;
@synthesize indicatorSpace ;

#pragma mark -
#pragma mark Initializers - dealloc

- (id)initWithType:(CustomPageControlType)theType
{
    self = [self initWithFrame: CGRectZero] ;
    [self setType: theType] ;
    return self ;
}

- (id)init
{
    self = [self initWithFrame: CGRectZero] ;
    return self ;
}

- (id)initWithFrame:(CGRect)frame
{
    if ((self = [super initWithFrame: CGRectZero]))
    {
        self.backgroundColor = [UIColor clearColor] ;
    }
    return self ;
}

- (void)dealloc {
    [onColor release], onColor = nil ;
    [offColor release], offColor = nil ;
    
    [super dealloc] ;
}


#pragma mark -
#pragma mark drawRect

- (void)drawRect:(CGRect)rect
{
    // get the current context
    CGContextRef context = UIGraphicsGetCurrentContext() ;
    
    // save the context
    CGContextSaveGState(context) ;
    
    // allow antialiasing
    CGContextSetAllowsAntialiasing(context, TRUE) ;
    
    // get the caller's diameter if it has been set or use the default one
    CGFloat diameter = (indicatorDiameter > 0) ? indicatorDiameter : kDotDiameter ;
    CGFloat space = (indicatorSpace > 0) ? indicatorSpace : kDotSpace ;
    
    // geometry
    CGRect currentBounds = self.bounds ;
    CGFloat dotsWidth = self.numberOfPages * diameter + MAX(0, self.numberOfPages - 1) * space ;
    CGFloat x = CGRectGetMidX(currentBounds) - dotsWidth / 2 ;
    CGFloat y = CGRectGetMidY(currentBounds) - diameter / 2 ;
    
    // get the caller's colors it they have been set or use the defaults
    CGColorRef onColorCG = onColor ? onColor.CGColor : [UIColor colorWithWhite: 1.0f alpha: 1.0f].CGColor ;
    CGColorRef offColorCG = offColor ? offColor.CGColor : [UIColor colorWithWhite: 0.7f alpha: 0.5f].CGColor ;
    
    // actually draw the dots
    for (int i = 0 ; i < numberOfPages ; i++)
    {
        CGRect dotRect = CGRectMake(x, y, diameter, diameter) ;
        
        if (i == currentPage)
        {
            if (type == CustomPageControlTypeOnImageOffImage) {
                [onImage drawInRect:dotRect];
            }
            else if (type == CustomPageControlTypeOnFullOffFull || type == CustomPageControlTypeOnFullOffEmpty)
            {
                CGContextSetFillColorWithColor(context, onColorCG) ;
                CGContextFillEllipseInRect(context, CGRectInset(dotRect, -1.0f, -1.0f)) ;
            }
            else
            {
                CGContextSetStrokeColorWithColor(context, onColorCG) ;
                CGContextStrokeEllipseInRect(context, dotRect) ;
            }
        }
        else
        {
            if (type == CustomPageControlTypeOnImageOffImage) {
                [offImage drawInRect:dotRect];
            }
            else if (type == CustomPageControlTypeOnEmptyOffEmpty || type == CustomPageControlTypeOnFullOffEmpty)
            {
                CGContextSetStrokeColorWithColor(context, offColorCG) ;
                CGContextStrokeEllipseInRect(context, dotRect) ;
            }
            else
            {
                CGContextSetFillColorWithColor(context, offColorCG) ;
                CGContextFillEllipseInRect(context, CGRectInset(dotRect, -1.0f, -1.0f)) ;
            }
        }
        
        x += diameter + space ;
    }
    
    // restore the context
    CGContextRestoreGState(context) ;
}


#pragma mark -
#pragma mark Accessors

- (void)setCurrentPage:(NSInteger)pageNumber
{
    // no need to update in that case
    if (currentPage == pageNumber)
        return ;
    
    // determine if the page number is in the available range
    currentPage = MIN(MAX(0, pageNumber), numberOfPages - 1) ;
    
    // in case we do not defer the page update, we redraw the view
    if (self.defersCurrentPageDisplay == NO)
        [self setNeedsDisplay] ;
}

- (void)setNumberOfPages:(NSInteger)numOfPages
{
    // make sure the number of pages is positive
    numberOfPages = MAX(0, numOfPages) ;
    
    // we then need to update the current page
    currentPage = MIN(MAX(0, currentPage), numberOfPages - 1) ;
    
    // correct the bounds accordingly
    self.bounds = self.bounds ;
    
    // we need to redraw
    [self setNeedsDisplay] ;
    
    // depending on the user preferences, we hide the page control with a single element
    if (hidesForSinglePage && (numOfPages < 2))
        [self setHidden: YES] ;
    else
        [self setHidden: NO] ;
}

- (void)setHidesForSinglePage:(BOOL)hide
{
    hidesForSinglePage = hide ;
    
    // depending on the user preferences, we hide the page control with a single element
    if (hidesForSinglePage && (numberOfPages < 2))
        [self setHidden: YES] ;
}

- (void)setDefersCurrentPageDisplay:(BOOL)defers
{
    defersCurrentPageDisplay = defers ;
}

- (void)setType:(CustomPageControlType)aType
{
    type = aType ;
    
    [self setNeedsDisplay] ;
}

- (void)setOnColor:(UIColor *)aColor
{
    [aColor retain] ;
    [onColor release] ;
    onColor = aColor ;
    
    [self setNeedsDisplay] ;
}

- (void)setOffColor:(UIColor *)aColor
{
    [aColor retain] ;
    [offColor release] ;
    offColor = aColor ;
    
    [self setNeedsDisplay] ;
}

- (void)setIndicatorDiameter:(CGFloat)aDiameter
{
    indicatorDiameter = aDiameter ;
    
    // correct the bounds accordingly
    self.bounds = self.bounds ;
    
    [self setNeedsDisplay] ;
}

- (void)setIndicatorSpace:(CGFloat)aSpace
{
    indicatorSpace = aSpace ;
    
    // correct the bounds accordingly
    self.bounds = self.bounds ;
    
    [self setNeedsDisplay] ;
}

- (void)setFrame:(CGRect)aFrame
{
    // we do not allow the caller to modify the size struct in the frame so we compute it
    aFrame.size = [self sizeForNumberOfPages: numberOfPages] ;
    super.frame = aFrame ;
}

- (void)setBounds:(CGRect)aBounds
{
    // we do not allow the caller to modify the size struct in the bounds so we compute it
    aBounds.size = [self sizeForNumberOfPages: numberOfPages] ;
    super.bounds = aBounds ;
}



#pragma mark -
#pragma mark UIPageControl methods

- (void)updateCurrentPageDisplay
{
    // ignores this method if the value of defersPageIndicatorUpdate is NO
    if (self.defersCurrentPageDisplay == NO)
        return ;
    
    // in case it is YES, we redraw the view (that will update the page control to the correct page)
    [self setNeedsDisplay] ;
}

- (CGSize)sizeForNumberOfPages:(NSInteger)pageCount
{
    CGFloat diameter = (indicatorDiameter > 0) ? indicatorDiameter : kDotDiameter ;
    CGFloat space = (indicatorSpace > 0) ? indicatorSpace : kDotSpace ;
    
    return CGSizeMake(pageCount * diameter + (pageCount - 1) * space + 44.0f, MAX(44.0f, diameter + 4.0f)) ;
}


#pragma mark -
#pragma mark Touches handlers

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
    // get the touch location
    UITouch *theTouch = [touches anyObject] ;
    CGPoint touchLocation = [theTouch locationInView: self] ;
    
    // check whether the touch is in the right or left hand-side of the control
    if (touchLocation.x < (self.bounds.size.width / 2))
        self.currentPage = MAX(self.currentPage - 1, 0) ;
    else
        self.currentPage = MIN(self.currentPage + 1, numberOfPages - 1) ;
    
    // send the value changed action to the target
    [self sendActionsForControlEvents: UIControlEventValueChanged] ;
}

@end