/*
 * Hedgewars-iOS, a Hedgewars port for iOS devices
 * Copyright (c) 2009-2011 Vittorio Giovara <vittorio.giovara@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * File created on 06/02/2012.
 */

// class heavily based on: http://blog.neuwert-media.com/2011/04/customized-uislider-with-visual-value-tracking/


#import "ValueTrackingSliderView.h"

#pragma mark -
#pragma mark Private UIView subclass rendering the popup showing slider value
@interface SliderValuePopupView : UIView  
@property (nonatomic) float value;
@property (nonatomic, retain) UIFont *font;
@property (nonatomic, retain) NSString *text;
@end

@implementation SliderValuePopupView

@synthesize value = _value;
@synthesize font = _font;
@synthesize text = _text;

-(id) initWithFrame:(CGRect) frame {
    self = [super initWithFrame:frame];
    if (self) {
        self.font = [UIFont boldSystemFontOfSize:18];
    }
    return self;
}

-(void) dealloc {
    self.text = nil;
    self.font = nil;
    [super dealloc];
}

-(void) drawRect:(CGRect) rect {
    // Create the path for the rounded rectangle
    CGRect roundedRect = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, self.bounds.size.width, floorf(self.bounds.size.height * 0.8));
    UIBezierPath *roundedRectPath = [UIBezierPath bezierPathWithRoundedRect:roundedRect cornerRadius:6.0];
    roundedRectPath.lineWidth = 2.0f;

    // Create the arrow path
    UIBezierPath *arrowPath = [UIBezierPath bezierPath];
    CGFloat midX = CGRectGetMidX(self.bounds);
    CGPoint p0 = CGPointMake(midX, CGRectGetMaxY(self.bounds));
    [arrowPath moveToPoint:p0];
    [arrowPath addLineToPoint:CGPointMake((midX - 10.0), CGRectGetMaxY(roundedRect))];
    [arrowPath addLineToPoint:CGPointMake((midX + 10.0), CGRectGetMaxY(roundedRect))];
    [arrowPath closePath];
    
    // Attach the arrow path to the rounded rect
    [roundedRectPath appendPath:arrowPath];

    // Color various sections
    [[UIColor blackColor] setFill];
    [roundedRectPath fill];
    [[UIColor whiteColor] setStroke];
    [roundedRectPath stroke];
    [[UIColor whiteColor] setFill];
    [arrowPath fill];

    // Draw the text
    if (self.text) {
        [[UIColor lightYellowColor] set];
        CGSize s = [_text sizeWithFont:self.font];
        CGFloat yOffset = (roundedRect.size.height - s.height) / 2;
        CGRect textRect = CGRectMake(roundedRect.origin.x, yOffset, roundedRect.size.width, s.height);
        
        [_text drawInRect:textRect 
                 withFont:self.font 
            lineBreakMode:UILineBreakModeWordWrap 
                alignment:UITextAlignmentCenter];    
    }
}

@end

#pragma mark -
#pragma mark MNEValueTrackingSlider implementations
@implementation ValueTrackingSliderView

@synthesize thumbRect, textValue;

#pragma Private methods

-(void) _constructSlider {
    valuePopupView = [[SliderValuePopupView alloc] initWithFrame:CGRectZero];
    valuePopupView.backgroundColor = [UIColor clearColor];
    valuePopupView.alpha = 0.0;
    [self addSubview:valuePopupView];
}

-(void) _fadePopupViewInAndOut:(BOOL)aFadeIn {
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.25];
    if (aFadeIn) {
        valuePopupView.alpha = 1.0;
    } else {
        valuePopupView.alpha = 0.0;
    }
    [UIView commitAnimations];
}

-(void) _positionAndUpdatePopupView {
    CGRect _thumbRect = self.thumbRect;
    CGRect popupRect = CGRectOffset(_thumbRect, 0, -floorf(_thumbRect.size.height * 1.5));
    valuePopupView.frame = CGRectInset(popupRect, -100, -15);
    valuePopupView.text = self.textValue;
    [valuePopupView setNeedsDisplay];
}

#pragma mark Memory management

-(id) initWithFrame:(CGRect) frame {
    self = [super initWithFrame:frame];
    if (self) {
        [self _constructSlider];
    }
    return self;
}

-(id) initWithCoder:(NSCoder *)aDecoder {
    self = [super initWithCoder:aDecoder];
    if (self) {
        [self _constructSlider];
    }
    return self;
}

-(void) dealloc {
    [valuePopupView release];
    [textValue release];
    [super dealloc];
}

#pragma mark -
#pragma mark UIControl touch event tracking
-(BOOL) beginTrackingWithTouch:(UITouch *)touch withEvent:(UIEvent *)event {
    // Fade in and update the popup view
    CGPoint touchPoint = [touch locationInView:self];
    // Check if the knob is touched. Only in this case show the popup-view
    if(CGRectContainsPoint(CGRectInset(self.thumbRect, -12.0, -12.0), touchPoint)) {
        [self _positionAndUpdatePopupView];
        [self _fadePopupViewInAndOut:YES]; 
    }
    return [super beginTrackingWithTouch:touch withEvent:event];
}

-(BOOL) continueTrackingWithTouch:(UITouch *)touch withEvent:(UIEvent *)event {
    // Update the popup view as slider knob is being moved
    [self _positionAndUpdatePopupView];
    return [super continueTrackingWithTouch:touch withEvent:event];
}

-(void) cancelTrackingWithEvent:(UIEvent *)event {
    [super cancelTrackingWithEvent:event];
}

-(void) endTrackingWithTouch:(UITouch *)touch withEvent:(UIEvent *)event {
    // Fade out the popoup view
    [self _fadePopupViewInAndOut:NO];
    [super endTrackingWithTouch:touch withEvent:event];
}

#pragma mark -
#pragma mark Custom property accessors
-(CGRect) thumbRect {
    CGRect trackRect = [self trackRectForBounds:self.bounds];
    CGRect thumbR = [self thumbRectForBounds:self.bounds 
                                         trackRect:trackRect
                                             value:self.value];
    return thumbR;
}

@end