#import "AQGridViewData.h"

#import "AQGridView.h"

@interface AQGridViewData (AQGridViewDataPrivate)

- (void) fixDesiredCellSizeForWidth: (CGFloat) width;

@implementation AQGridViewData

@synthesize reorderedIndex=_reorderedIndex, numberOfItems=_numberOfItems, topPadding=_topPadding, bottomPadding=_bottomPadding, leftPadding=_leftPadding, rightPadding=_rightPadding, layoutDirection=_layoutDirection;

- (id) initWithGridView: (AQGridView *) gridView

{

self = [super init];

if ( self == nil )

return ( nil );

_gridView = gridView;

_boundsSize = gridView.bounds.size;

return ( self );

}

- (id) copyWithZone: (NSZone *) zone

{

AQGridViewData * theCopy = [[AQGridViewData allocWithZone: zone] initWithGridView: _gridView];

theCopy->_desiredCellSize = _desiredCellSize;

theCopy->_actualCellSize = _actualCellSize;

theCopy->_layoutDirection = _layoutDirection;

theCopy->_topPadding = _topPadding;

theCopy->_bottomPadding = _bottomPadding;

theCopy->_leftPadding = _leftPadding;

theCopy->_rightPadding = _rightPadding;

theCopy->_numberOfItems = _numberOfItems;

theCopy->_reorderedIndex = _reorderedIndex;

return ( theCopy );

}

- (id) mutableCopyWithZone: (NSZone *) zone

{

return ( [self copyWithZone: zone] );

}

- (void) gridViewDidChangeBoundsSize: (CGSize) boundsSize

{

_boundsSize = boundsSize;

if ( _layoutDirection == AQGridViewLayoutDirectionVertical )

[self fixDesiredCellSizeForWidth: boundsSize.width];

}

- (NSUInteger) itemIndexForPoint: (CGPoint) point

{

// adjust for top padding

point.y -= _topPadding;

point.x -= _leftPadding;

// get a count of all rows before the one containing the point

NSUInteger y = (NSUInteger)floorf(point.y);

NSUInteger row = y / (NSUInteger)_actualCellSize.height;

// now column

NSUInteger x = (NSUInteger)floorf(point.x);

NSUInteger col = x / (NSUInteger)_actualCellSize.width;

NSUInteger result = (row * [self numberOfItemsPerRow]) + col;

if ( result >= self.numberOfItems )

result = NSNotFound;

return ( result );

}

- (BOOL) pointIsInLastRow: (CGPoint) point

{

CGRect rect = [self rectForEntireGrid];

if ( _layoutDirection == AQGridViewLayoutDirectionVertical )

return ( point.y >= (rect.size.height - _actualCellSize.height) );

// 'else'

return ( point.x >= (rect.size.width - _actualCellSize.width) );

}

- (CGRect) cellRectForPoint: (CGPoint) point

{

return ( [self cellRectAtIndex: [self itemIndexForPoint: point]] );

}

- (void) setDesiredCellSize: (CGSize) desiredCellSize

{

_desiredCellSize = desiredCellSize;

if ( _layoutDirection == AQGridViewLayoutDirectionVertical )

[self fixDesiredCellSizeForWidth: _boundsSize.width];

else

_actualCellSize = _desiredCellSize;

}

- (void) setLayoutDirection: (AQGridViewLayoutDirection) direction

{

if ( direction == AQGridViewLayoutDirectionVertical )

[self fixDesiredCellSizeForWidth: _boundsSize.width];

else

_actualCellSize = _desiredCellSize;

_layoutDirection = direction;

}

- (CGSize) cellSize

{

return ( _actualCellSize );

}

- (CGRect) rectForEntireGrid

{

CGRect rect;

rect.origin.x = _leftPadding;

rect.origin.y = _topPadding;

rect.size = [self sizeForEntireGrid];

return ( rect );

}

- (CGSize) sizeForEntireGrid

{

NSUInteger numPerRow = [self numberOfItemsPerRow];

if ( numPerRow == 0 ) // avoid a divide-by-zero exception

return ( CGSizeZero );

NSUInteger numRows = _numberOfItems / numPerRow;

if ( _numberOfItems % numPerRow != 0 )

numRows++;

CGFloat height = ( ((CGFloat)ceilf((CGFloat)numRows * _actualCellSize.height)) + _topPadding + _bottomPadding );

if (height < _gridView.bounds.size.height)

height = _gridView.bounds.size.height;

return ( CGSizeMake(((CGFloat)ceilf(_actualCellSize.width * numPerRow)) + _leftPadding + _rightPadding, height) );

}

- (NSUInteger) numberOfItemsPerRow

{

if ( _layoutDirection == AQGridViewLayoutDirectionVertical )

return ( (NSUInteger)floorf(_boundsSize.width / _actualCellSize.width) );

// work out how many rows we can fit

NSUInteger rows = (NSUInteger)floorf(_boundsSize.height / _actualCellSize.height);

if (0 == rows) {

rows = 1;

}

NSUInteger cols = _numberOfItems / rows;

if ( _numberOfItems % rows != 0 )

cols++;

return ( cols );

}

- (CGRect) cellRectAtIndex: (NSUInteger) index

{

NSUInteger numPerRow = [self numberOfItemsPerRow];

if ( numPerRow == 0 ) // avoid a divide-by-zero exception

return ( CGRectZero );

NSUInteger skipRows = index / numPerRow;

NSUInteger skipCols = index % numPerRow;

CGRect result = CGRectZero;

result.origin.x = _actualCellSize.width * (CGFloat)skipCols + _leftPadding;

result.origin.y = (_actualCellSize.height * (CGFloat)skipRows) + _topPadding;

result.size = _actualCellSize;

return ( result );

}

- (NSIndexSet *) indicesOfCellsInRect: (CGRect) aRect

{

NSMutableIndexSet * result = [NSMutableIndexSet indexSet];

NSUInteger numPerRow = [self numberOfItemsPerRow];

for ( NSUInteger i = 0; i < _numberOfItems; i++ )

{

CGRect cellRect = [self cellRectAtIndex: i];

if ( CGRectGetMaxY(cellRect) < CGRectGetMinY(aRect) )

{

// jump forward to the next row

i += (numPerRow - 1);

continue;

}

if ( CGRectIntersectsRect(cellRect, aRect) )

{

[result addIndex: i];

if ( (CGRectGetMaxY(cellRect) > CGRectGetMaxY(aRect)) &&

(CGRectGetMaxX(cellRect) > CGRectGetMaxX(aRect)) )

{

// passed the bottom-right edge of the given rect

break;

}

}

}

return ( result );

}

@implementation AQGridViewData (AQGridViewDataPrivate)

- (void) fixDesiredCellSizeForWidth: (CGFloat) width

{

// Much thanks to Brandon Sneed (@bsneed) for the following new algorithm, reduced to two floating-point divisions -- that's O(1) folks!

CGFloat w = floorf(width - _leftPadding - _rightPadding);

CGFloat dw = floorf(_desiredCellSize.width);

CGFloat multiplier = floorf( w / dw );

_actualCellSize.width = floorf( w / multiplier );

_actualCellSize.height = _desiredCellSize.height;

}