/*
 * CPSplitView.j
 * AppKit
 *
 * Created by Thomas Robinson.
 * Copyright 2008, 280 North, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

@import "CPImage.j"
@import "CPView.j"

#include "CoreGraphics/CGGeometry.h"
#include "Platform/Platform.h"
#include "Platform/DOM/CPDOMDisplayServer.h"


CPSplitViewDidResizeSubviewsNotification = @"CPSplitViewDidResizeSubviewsNotification";
CPSplitViewWillResizeSubviewsNotification = @"CPSplitViewWillResizeSubviewsNotification";

var CPSplitViewHorizontalImage = nil,
    CPSplitViewVerticalImage = nil;

/*!
    @ingroup appkit
*/

@implementation CPSplitView : CPView
{
    id          _delegate;
    BOOL        _isVertical;
    BOOL        _isPaneSplitter;
    
    int         _currentDivider;
    float       _initialOffset;
    
    CPString    _originComponent;
    CPString    _sizeComponent;
    
    CPArray     _DOMDividerElements;
    CPString    _dividerImagePath;
    int         _drawingDivider;
    
    BOOL        _needsResizeSubviews;
}

/*
    @ignore
*/
+ (void)initialize
{
    if (self != [CPSplitView class])
        return;

    var bundle = [CPBundle bundleForClass:self];
    CPSplitViewHorizontalImage = [[CPImage alloc] initWithContentsOfFile:[bundle pathForResource:@"CPSplitView/CPSplitViewHorizontal.png"] size:CPSizeMake(5.0, 10.0)];
    CPSplitViewVerticalImage = [[CPImage alloc] initWithContentsOfFile:[bundle pathForResource:@"CPSplitView/CPSplitViewVertical.png"] size:CPSizeMake(10.0, 5.0)];
}

- (id)initWithFrame:(CGRect)aFrame
{
    if (self = [super initWithFrame:aFrame])
    {
        _currentDivider = CPNotFound;
        
        _DOMDividerElements = [];
        
        [self _setVertical:YES];
    }
    
    return self;
}

- (float)dividerThickness
{
    return _isPaneSplitter ? 1.0 : 10.0;
}

- (BOOL)isVertical
{
    return _isVertical;
}

- (void)setVertical:(BOOL)shouldBeVertical
{
    if (![self _setVertical:shouldBeVertical])
        return;
    
    // Just re-adjust evenly.
    var frame = [self frame],
        dividerThickness = [self dividerThickness];
    
    [self _postNotificationWillResize];
    
    var eachSize = ROUND((frame.size[_sizeComponent] - dividerThickness * (_subviews.length - 1)) / _subviews.length),
        index = 0,
        count = _subviews.length;

    if ([self isVertical])
        for (; index < count; ++index)
            [_subviews[index] setFrame:CGRectMake(ROUND((eachSize + dividerThickness) * index), 0, eachSize, frame.size.height)];
    else
        for (; index < count; ++index)
            [_subviews[index] setFrame:CGRectMake(0, ROUND((eachSize + dividerThickness) * index), frame.size.width, eachSize)];
    
    [self setNeedsDisplay:YES];
    
    [self _postNotificationDidResize];

}

- (BOOL)_setVertical:(BOOL)shouldBeVertical
{
    var changed = (_isVertical != shouldBeVertical);
    
    _isVertical = shouldBeVertical;
    
    _originComponent = [self isVertical] ? "x" : "y";
    _sizeComponent = [self isVertical] ? "width" : "height";
    _dividerImagePath = [self isVertical] ? [CPSplitViewVerticalImage filename] : [CPSplitViewHorizontalImage filename];
    
    return changed;
}

- (BOOL)isPaneSplitter
{
    return _isPaneSplitter;
}

- (void)setIsPaneSplitter:(BOOL)shouldBePaneSplitter
{
    if (_isPaneSplitter == shouldBePaneSplitter)
        return;
    
    _isPaneSplitter = shouldBePaneSplitter;

#if PLATFORM(DOM)
    _DOMDividerElements = [];
#endif

    // The divider changes size when pane splitter mode is toggled, so the 
    // subviews need to change size too.
    _needsResizeSubviews = YES;
    [self setNeedsDisplay:YES];
}

- (void)didAddSubview:(CPView)aSubview
{
    _needsResizeSubviews = YES;
//    [self adjustSubviews];
}

- (BOOL)isSubviewCollapsed:(CPView)subview
{
    return [subview frame].size[_sizeComponent] < 1 ? YES : NO;
}

- (CGRect)rectOfDividerAtIndex:(int)aDivider
{
    var frame = [_subviews[aDivider] frame],
        rect = CGRectMakeZero();
    
    rect.size = [self frame].size;
    
    rect.size[_sizeComponent] = [self dividerThickness];
    rect.origin[_originComponent] = frame.origin[_originComponent] + frame.size[_sizeComponent];

    return rect;
}

- (CGRect)effectiveRectOfDividerAtIndex:(int)aDivider
{
    var realRect = [self rectOfDividerAtIndex:aDivider];
    
    var padding = 2;
    
    realRect.size[_sizeComponent] += padding * 2;
    realRect.origin[_originComponent] -= padding;
    
    return realRect;
}

- (void)drawRect:(CGRect)rect
{
    var count = [_subviews count] - 1;
    
    while ((count--) > 0)
    {
        _drawingDivider = count;
        [self drawDividerInRect:[self rectOfDividerAtIndex:count]];
    }
}

- (void)drawDividerInRect:(CGRect)aRect
{
#if PLATFORM(DOM)
    if (!_DOMDividerElements[_drawingDivider])
    {
        _DOMDividerElements[_drawingDivider] = document.createElement("div");
        _DOMDividerElements[_drawingDivider].style.cursor = "move";
        _DOMDividerElements[_drawingDivider].style.position = "absolute";
        _DOMDividerElements[_drawingDivider].style.backgroundRepeat = "repeat";

        CPDOMDisplayServerAppendChild(_DOMElement, _DOMDividerElements[_drawingDivider]);

        if (_isPaneSplitter)
        {
            _DOMDividerElements[_drawingDivider].style.backgroundColor = "#A5A5A5";
            _DOMDividerElements[_drawingDivider].style.backgroundImage = "";
        }
        else
        {
            _DOMDividerElements[_drawingDivider].style.backgroundColor = "";
            _DOMDividerElements[_drawingDivider].style.backgroundImage = "url('"+_dividerImagePath+"')";
        }
    }    

    CPDOMDisplayServerSetStyleLeftTop(_DOMDividerElements[_drawingDivider], NULL, _CGRectGetMinX(aRect), _CGRectGetMinY(aRect));
    CPDOMDisplayServerSetStyleSize(_DOMDividerElements[_drawingDivider], _CGRectGetWidth(aRect), _CGRectGetHeight(aRect));
#endif
}

- (void)viewWillDraw
{
    [self _adjustSubviewsWithCalculatedSize];
}

- (void)_adjustSubviewsWithCalculatedSize
{
    if (!_needsResizeSubviews)
        return;
    
    _needsResizeSubviews = NO;
        
    var subviews = [self subviews],
        count = subviews.length,
        oldSize = CGSizeMakeZero();
    
    if ([self isVertical])
    {
        oldSize.width += [self dividerThickness] * (count - 1);
        oldSize.height = CGRectGetHeight([self frame]);
    }
    else
    {
        oldSize.width = CGRectGetWidth([self frame]);
        oldSize.height += [self dividerThickness] * (count - 1);
    }
        
    while (count--)
        oldSize[_sizeComponent] += [subviews[count] frame].size[_sizeComponent];
    
    [self resizeSubviewsWithOldSize:oldSize];
}

- (BOOL)cursorAtPoint:(CPPoint)aPoint hitDividerAtIndex:(int)anIndex
{
    var frame = [_subviews[anIndex] frame],
        startPosition = frame.origin[_originComponent] + frame.size[_sizeComponent],
        effectiveRect = [self effectiveRectOfDividerAtIndex:anIndex],
        additionalRect = null;
    
    if ([_delegate respondsToSelector:@selector(splitView:effectiveRect:forDrawnRect:ofDividerAtIndex:)])
        effectiveRect = [_delegate splitView:self effectiveRect:effectiveRect forDrawnRect:effectiveRect ofDividerAtIndex:anIndex];
    
    if ([_delegate respondsToSelector:@selector(splitView:additionalEffectiveRectOfDividerAtIndex:)])
        additionalRect = [_delegate splitView:self additionalEffectiveRectOfDividerAtIndex:anIndex];

    return CGRectContainsPoint(effectiveRect, aPoint) || (additionalRect && CGRectContainsPoint(additionalRect, aPoint));
}

- (CPView)hitTest:(CGPoint)aPoint
{
    if ([self isHidden] || ![self hitTests] || !CGRectContainsPoint([self frame], aPoint))
        return nil;
    
    var point = [self convertPoint:aPoint fromView:[self superview]];
    
    var count = [_subviews count] - 1;
    for (var i = 0; i < count; i++)
    {
        if ([self cursorAtPoint:point hitDividerAtIndex:i])
            return self;
    }
    
    return [super hitTest:aPoint];
}

/*
    Tracks the divider.
    @param anEvent the input event
*/
- (void)trackDivider:(CPEvent)anEvent
{
    var type = [anEvent type];

    if (type == CPLeftMouseUp)
    {
        if (_currentDivider != CPNotFound)
        {
            _currentDivider = CPNotFound;
            [self _postNotificationDidResize];
        }
        
        return;
    }
    
    if (type == CPLeftMouseDown)
    {
        var point = [self convertPoint:[anEvent locationInWindow] fromView:nil];

        _currentDivider = CPNotFound;
        var count = [_subviews count] - 1;
        for (var i = 0; i < count; i++)
        {
            var frame = [_subviews[i] frame],
                startPosition = frame.origin[_originComponent] + frame.size[_sizeComponent];

            if ([self cursorAtPoint:point hitDividerAtIndex:i])
            {
                if ([anEvent clickCount] == 2 &&
                    [_delegate respondsToSelector:@selector(splitView:canCollapseSubview:)] &&
                    [_delegate respondsToSelector:@selector(splitView:shouldCollapseSubview:forDoubleClickOnDividerAtIndex:)])
                {    
                    var minPosition = [self minPossiblePositionOfDividerAtIndex:i],
                        maxPosition = [self maxPossiblePositionOfDividerAtIndex:i];

                    if ([_delegate splitView:self canCollapseSubview:_subviews[i]] && [_delegate splitView:self shouldCollapseSubview:_subviews[i] forDoubleClickOnDividerAtIndex:i])
                    {
                        if ([self isSubviewCollapsed:_subviews[i]])
                            [self setPosition:(minPosition + (maxPosition - minPosition) / 2) ofDividerAtIndex:i];
                        else
                            [self setPosition:minPosition ofDividerAtIndex:i];
                    }
                    else if ([_delegate splitView:self canCollapseSubview:_subviews[i+1]] && [_delegate splitView:self shouldCollapseSubview:_subviews[i+1] forDoubleClickOnDividerAtIndex:i])
                    {
                        if ([self isSubviewCollapsed:_subviews[i+1]])
                            [self setPosition:(minPosition + (maxPosition - minPosition) / 2) ofDividerAtIndex:i];
                        else
                            [self setPosition:maxPosition ofDividerAtIndex:i];
                    }
                }
                else
                {
                    _currentDivider = i;
                    _initialOffset = startPosition - point[_originComponent];

                    [self _postNotificationWillResize];
                }
            }
        }

        if (_currentDivider === CPNotFound)
            return;
    }
    
    else if (type == CPLeftMouseDragged && _currentDivider != CPNotFound)
    {
        var point = [self convertPoint:[anEvent locationInWindow] fromView:nil];
        
        [self setPosition:(point[_originComponent] + _initialOffset) ofDividerAtIndex:_currentDivider];
    }
    
    [CPApp setTarget:self selector:@selector(trackDivider:) forNextEventMatchingMask:CPLeftMouseDraggedMask | CPLeftMouseUpMask untilDate:nil inMode:nil dequeue:YES];
}

- (void)mouseDown:(CPEvent)anEvent
{
    // FIXME: This should not trap events if not on a divider!
    [self trackDivider:anEvent];
}

- (float)maxPossiblePositionOfDividerAtIndex:(int)dividerIndex
{
    var frame = [_subviews[dividerIndex + 1] frame];
    
    if (dividerIndex + 1 < [_subviews count] - 1)
        return frame.origin[_originComponent] + frame.size[_sizeComponent] - [self dividerThickness];
    else    
        return [self frame].size[_sizeComponent] - [self dividerThickness];
}

- (float)minPossiblePositionOfDividerAtIndex:(int)dividerIndex
{
    if (dividerIndex > 0)
    {
        var frame = [_subviews[dividerIndex - 1] frame];
        
        return frame.origin[_originComponent] + frame.size[_sizeComponent] + [self dividerThickness];
    }
    else    
        return 0;
}

- (void)setPosition:(float)position ofDividerAtIndex:(int)dividerIndex
{
    [self _adjustSubviewsWithCalculatedSize];
        
    // not sure where this should override other positions?
    if ([_delegate respondsToSelector:@selector(splitView:constrainSplitPosition:ofSubviewAt:)])
        position = [_delegate splitView:self constrainSplitPosition:position ofSubviewAt:dividerIndex];

    var proposedMax = [self maxPossiblePositionOfDividerAtIndex:dividerIndex],
        proposedMin = [self minPossiblePositionOfDividerAtIndex:dividerIndex],
        actualMax = proposedMax,
        actualMin = proposedMin;
        
    if([_delegate respondsToSelector:@selector(splitView:constrainMinCoordinate:ofSubviewAt:)])
        actualMin = [_delegate splitView:self constrainMinCoordinate:proposedMin ofSubviewAt:dividerIndex];
        
    if([_delegate respondsToSelector:@selector(splitView:constrainMaxCoordinate:ofSubviewAt:)])
        actualMax = [_delegate splitView:self constrainMaxCoordinate:proposedMax ofSubviewAt:dividerIndex];

    var frame = [self frame],
        viewA = _subviews[dividerIndex],
        frameA = [viewA frame],
        viewB = _subviews[dividerIndex + 1],
        frameB = [viewB frame];

    var realPosition = MAX(MIN(position, actualMax), actualMin);
    
    if (position <  proposedMin + (actualMin - proposedMin) / 2)
        if ([_delegate respondsToSelector:@selector(splitView:canCollapseSubview:)])
            if ([_delegate splitView:self canCollapseSubview:viewA])
                realPosition = proposedMin;
    
    frameA.size[_sizeComponent] = realPosition - frameA.origin[_originComponent];
    [_subviews[dividerIndex] setFrame:frameA];
    
    frameB.size[_sizeComponent] = frameB.origin[_originComponent] + frameB.size[_sizeComponent] - realPosition - [self dividerThickness];
    frameB.origin[_originComponent] = realPosition + [self dividerThickness];
    [_subviews[dividerIndex + 1] setFrame:frameB];
    
    [self setNeedsDisplay:YES];
}

- (void)setFrameSize:(CGSize)aSize
{
    [self _adjustSubviewsWithCalculatedSize];
        
    [super setFrameSize:aSize];
    
    [self setNeedsDisplay:YES];
}

- (void)resizeSubviewsWithOldSize:(CPSize)oldSize
{   
    if ([_delegate respondsToSelector:@selector(splitView:resizeSubviewsWithOldSize:)])
    {
        [_delegate splitView:self resizeSubviewsWithOldSize:oldSize];
        return;
    }

    [self _postNotificationWillResize];
    
    var index = 0,
        count = [_subviews count],
        bounds = [self bounds],
        dividerThickness = [self dividerThickness],
        totalDividers = count - 1,
        totalSizableSpace = 0,
        nonSizableSpace = 0,
        lastSizableIndex = -1,
        totalSizablePanes = 0,
        isVertical = [self isVertical];

    for (index = 0; index < count; ++index)
    {
        var view = _subviews[index],
            isSizable = isVertical ? [view autoresizingMask] & CPViewWidthSizable : [view autoresizingMask] & CPViewHeightSizable;

        if (isSizable)
        {
            totalSizableSpace += [view frame].size[_sizeComponent];
            lastSizableIndex = index;
            totalSizablePanes++;
        }
    }

    if (totalSizablePanes === count)
        totalSizableSpace = 0;

    var nonSizableSpace = totalSizableSpace ? bounds.size[_sizeComponent] - totalSizableSpace : 0,
        remainingFlexibleSpace = bounds.size[_sizeComponent] - oldSize[_sizeComponent],
        oldDimension = (oldSize[_sizeComponent]- totalDividers*dividerThickness - nonSizableSpace),
        ratio = oldDimension <= 0 ? 0 : (bounds.size[_sizeComponent] - totalDividers*dividerThickness - nonSizableSpace) / oldDimension;

    for (index = 0; index < count; ++index)
    {
        var view = _subviews[index],
            viewFrame = CGRectMakeCopy(bounds),
            isSizable = isVertical ? [view autoresizingMask] & CPViewWidthSizable : [view autoresizingMask] & CPViewHeightSizable;

            if (index + 1 == count)
                viewFrame.size[_sizeComponent] = bounds.size[_sizeComponent] - viewFrame.origin[_originComponent];
            else if (totalSizableSpace && isSizable && lastSizableIndex === index)
                viewFrame.size[_sizeComponent] = MAX(0, ROUND([view frame].size[_sizeComponent] + remainingFlexibleSpace))
            else if (isSizable || !totalSizableSpace)
            {
                viewFrame.size[_sizeComponent] = MAX(0, ROUND(ratio * [view frame].size[_sizeComponent]));
                remainingFlexibleSpace -= (viewFrame.size[_sizeComponent] - [view frame].size[_sizeComponent]);
            }
            else if (totalSizableSpace && !isSizable)
                viewFrame.size[_sizeComponent] = [view frame].size[_sizeComponent];
            else
                alert("SHOULD NEVER GET HERE");

        bounds.origin[_originComponent] += viewFrame.size[_sizeComponent] + dividerThickness;        

        [view setFrame:viewFrame];
    }

    [self _postNotificationDidResize];
}

- (void)setDelegate:(id)delegate
{
    if ([_delegate respondsToSelector:@selector(splitViewDidResizeSubviews:)])
        [[CPNotificationCenter defaultCenter] removeObserver:_delegate name:CPSplitViewDidResizeSubviewsNotification object:self];
    if ([_delegate respondsToSelector:@selector(splitViewWillResizeSubviews:)])
        [[CPNotificationCenter defaultCenter] removeObserver:_delegate name:CPSplitViewWillResizeSubviewsNotification object:self];
    
   _delegate = delegate;

   if ([_delegate respondsToSelector:@selector(splitViewDidResizeSubviews:)])
       [[CPNotificationCenter defaultCenter] addObserver:_delegate
                                                selector:@selector(splitViewDidResizeSubviews:)
                                                    name:CPSplitViewDidResizeSubviewsNotification
                                                  object:self];
   if ([_delegate respondsToSelector:@selector(splitViewWillResizeSubviews:)])
       [[CPNotificationCenter defaultCenter] addObserver:_delegate
                                                selector:@selector(splitViewWillResizeSubviews:)
                                                    name:CPSplitViewWillResizeSubviewsNotification
                                                  object:self];
}

- (void)_postNotificationWillResize
{
    [[CPNotificationCenter defaultCenter] postNotificationName:CPSplitViewWillResizeSubviewsNotification object:self];
}

- (void)_postNotificationDidResize
{
    [[CPNotificationCenter defaultCenter] postNotificationName:CPSplitViewDidResizeSubviewsNotification object:self];
}

@end

var CPSplitViewDelegateKey          = "CPSplitViewDelegateKey",
    CPSplitViewIsVerticalKey        = "CPSplitViewIsVerticalKey",
    CPSplitViewIsPaneSplitterKey    = "CPSplitViewIsPaneSplitterKey";

@implementation CPSplitView (CPCoding)

/*
    Initializes the split view by unarchiving data from \c aCoder.
    @param aCoder the coder containing the archived CPSplitView.
*/
- (id)initWithCoder:(CPCoder)aCoder
{
    self = [super initWithCoder:aCoder];
    
    if (self)
    {
        _currentDivider = CPNotFound;
        
        _DOMDividerElements = [];
        
        _delegate = [aCoder decodeObjectForKey:CPSplitViewDelegateKey];;
        
        _isPaneSplitter = [aCoder decodeBoolForKey:CPSplitViewIsPaneSplitterKey];
        [self _setVertical:[aCoder decodeBoolForKey:CPSplitViewIsVerticalKey]];
    }
    
    return self;
}

/*
    Archives this split view into the provided coder.
    @param aCoder the coder to which the button's instance data will be written.
*/
- (void)encodeWithCoder:(CPCoder)aCoder
{
    [super encodeWithCoder:aCoder];
    
    [aCoder encodeConditionalObject:_delegate forKey:CPSplitViewDelegateKey];
    
    [aCoder encodeBool:_isVertical forKey:CPSplitViewIsVerticalKey];
    [aCoder encodeBool:_isPaneSplitter forKey:CPSplitViewIsPaneSplitterKey];
}

@end