//
//  MGSplitDividerView.m
//  MGSplitView
//
//  Created by Matt Gemmell on 26/07/2010.
//  Copyright 2010 Instinctive Code.
//

#import "MGSplitDividerView.h"
#import "MGSplitViewController.h"


@implementation MGSplitDividerView


#pragma mark -
#pragma mark Setup and teardown


- (id)initWithFrame:(CGRect)frame
{
    if ((self = [super initWithFrame:frame])) {
        self.userInteractionEnabled = NO;
        self.allowsDragging = NO;
        self.contentMode = UIViewContentModeRedraw;
    }
    return self;
}


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


#pragma mark -
#pragma mark Drawing


- (void)drawRect:(CGRect)rect
{
    if (splitViewController.dividerStyle == MGSplitViewDividerStyleThin) {
        [super drawRect:rect];

    } else if (splitViewController.dividerStyle == MGSplitViewDividerStylePaneSplitter) {
        // Draw gradient background.
        CGRect bounds = self.bounds;
        CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();
        CGFloat locations[2] = {0, 1};
        CGFloat components[8] = {   0.988, 0.988, 0.988, 1.0,  // light
                                    0.875, 0.875, 0.875, 1.0 };// dark
        CGGradientRef gradient = CGGradientCreateWithColorComponents (rgb, components, locations, 2);
        CGContextRef context = UIGraphicsGetCurrentContext();
        CGPoint start, end;
        if (splitViewController.vertical) {
            // Light left to dark right.
            start = CGPointMake(CGRectGetMinX(bounds), CGRectGetMidY(bounds));
            end = CGPointMake(CGRectGetMaxX(bounds), CGRectGetMidY(bounds));
        } else {
            // Light top to dark bottom.
            start = CGPointMake(CGRectGetMidX(bounds), CGRectGetMinY(bounds));
            end = CGPointMake(CGRectGetMidX(bounds), CGRectGetMaxY(bounds));
        }
        CGContextDrawLinearGradient(context, gradient, start, end, 0);
        CGColorSpaceRelease(rgb);
        CGGradientRelease(gradient);

        // Draw borders.
        float borderThickness = 1.0;
        [[UIColor colorWithWhite:0.7 alpha:1.0] set];
        CGRect borderRect = bounds;
        if (splitViewController.vertical) {
            borderRect.size.width = borderThickness;
            UIRectFill(borderRect);
            borderRect.origin.x = CGRectGetMaxX(bounds) - borderThickness;
            UIRectFill(borderRect);

        } else {
            borderRect.size.height = borderThickness;
            UIRectFill(borderRect);
            borderRect.origin.y = CGRectGetMaxY(bounds) - borderThickness;
            UIRectFill(borderRect);
        }

        // Draw grip.
        [self drawGripThumbInRect:bounds];
    }
}


- (void)drawGripThumbInRect:(CGRect)rect
{
    float width = 9.0;
    float height;
    if (splitViewController.vertical) {
        height = 30.0;
    } else {
        height = width;
        width = 30.0;
    }

    // Draw grip in centred in rect.
    CGRect gripRect = CGRectMake(0, 0, width, height);
    gripRect.origin.x = ((rect.size.width - gripRect.size.width) / 2.0);
    gripRect.origin.y = ((rect.size.height - gripRect.size.height) / 2.0);

    float stripThickness = 1.0;
    UIColor *stripColor = [UIColor colorWithWhite:0.35 alpha:1.0];
    UIColor *lightColor = [UIColor colorWithWhite:1.0 alpha:1.0];
    float space = 3.0;
    if (splitViewController.vertical) {
        gripRect.size.width = stripThickness;
        [stripColor set];
        UIRectFill(gripRect);

        gripRect.origin.x += stripThickness;
        gripRect.origin.y += 1;
        [lightColor set];
        UIRectFill(gripRect);
        gripRect.origin.x -= stripThickness;
        gripRect.origin.y -= 1;

        gripRect.origin.x += space + stripThickness;
        [stripColor set];
        UIRectFill(gripRect);

        gripRect.origin.x += stripThickness;
        gripRect.origin.y += 1;
        [lightColor set];
        UIRectFill(gripRect);
        gripRect.origin.x -= stripThickness;
        gripRect.origin.y -= 1;

        gripRect.origin.x += space + stripThickness;
        [stripColor set];
        UIRectFill(gripRect);

        gripRect.origin.x += stripThickness;
        gripRect.origin.y += 1;
        [lightColor set];
        UIRectFill(gripRect);

    } else {
        gripRect.size.height = stripThickness;
        [stripColor set];
        UIRectFill(gripRect);

        gripRect.origin.y += stripThickness;
        gripRect.origin.x -= 1;
        [lightColor set];
        UIRectFill(gripRect);
        gripRect.origin.y -= stripThickness;
        gripRect.origin.x += 1;

        gripRect.origin.y += space + stripThickness;
        [stripColor set];
        UIRectFill(gripRect);

        gripRect.origin.y += stripThickness;
        gripRect.origin.x -= 1;
        [lightColor set];
        UIRectFill(gripRect);
        gripRect.origin.y -= stripThickness;
        gripRect.origin.x += 1;

        gripRect.origin.y += space + stripThickness;
        [stripColor set];
        UIRectFill(gripRect);

        gripRect.origin.y += stripThickness;
        gripRect.origin.x -= 1;
        [lightColor set];
        UIRectFill(gripRect);
    }
}


#pragma mark -
#pragma mark Interaction


- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];
    if (touch) {
        CGPoint lastPt = [touch previousLocationInView:self];
        CGPoint pt = [touch locationInView:self];
        float offset = (splitViewController.vertical) ? pt.x - lastPt.x : pt.y - lastPt.y;
        if (!splitViewController.masterBeforeDetail) {
            offset = -offset;
        }
        splitViewController.splitPosition = splitViewController.splitPosition + offset;
    }
}


#pragma mark -
#pragma mark Accessors and properties


- (void)setAllowsDragging:(BOOL)flag
{
    if (flag != allowsDragging) {
        allowsDragging = flag;
        self.userInteractionEnabled = allowsDragging;
    }
}


@synthesize splitViewController;
@synthesize allowsDragging;


@end