Telegram/Telegraph/TGCollectionMenuController.m

#import "TGCollectionMenuController.h"

#import "TGInterfaceAssets.h"
#import "TGImageUtils.h"

#import "TGCollectionMenuView.h"
#import "TGCollectionMenuLayout.h"

@interface TGCollectionMenuController () <UICollectionViewDataSource, UICollectionViewDelegateFlowLayout, TGCollectionMenuViewDelegate>
{
    bool _editingMode;
    
    NSMutableSet *_collectionRegisteredIdentifiers;
    
    CGFloat _currentLayoutWidth;
    
    UIView *_headerBackgroundView;
}

@end

@implementation TGCollectionMenuController

- (id)init
{
    self = [super init];
    if (self)
    {
        _menuSections = [[TGCollectionMenuSectionList alloc] init];
    }
    return self;
}

- (void)dealloc
{
    _collectionView.delegate = nil;
    _collectionView.dataSource = nil;
}

- (void)enterEditingMode:(bool)animated
{
    if (!_editingMode)
    {
        _editingMode = true;
        
        [_collectionView setEditing:true animated:animated];
        
        [self didEnterEditingMode:animated];
    }
}

- (void)leaveEditingMode:(bool)animated
{
    if (_editingMode)
    {
        _editingMode = false;
        
        [_collectionView setEditing:false animated:animated];
        
        [self didLeaveEditingMode:animated];
    }
}

- (void)didEnterEditingMode:(bool)__unused animated
{   
}

- (void)didLeaveEditingMode:(bool)__unused animated
{
}

- (void)_resetCollectionView
{
    if (_collectionView != nil)
    {
        _collectionView.delegate = nil;
        _collectionView.dataSource = nil;
        [_collectionView removeFromSuperview];
    }
    
    _currentLayoutWidth = self.view.frame.size.width;
    
    _collectionRegisteredIdentifiers = [[NSMutableSet alloc] init];
    
    _collectionLayout = [[TGCollectionMenuLayout alloc] init];
    _collectionView = [[TGCollectionMenuView alloc] initWithFrame:self.view.bounds collectionViewLayout:_collectionLayout];
    _collectionView.backgroundColor = nil;
    _collectionView.opaque = false;
    _collectionView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
    _collectionView.dataSource = self;
    _collectionView.delegate = self;
    
    _collectionView.alwaysBounceVertical = true;
    
    [_collectionView registerClass:[TGCollectionItemView class] forCellWithReuseIdentifier:@"_empty"];
    
    [self.view insertSubview:_collectionView aboveSubview:_headerBackgroundView];
}

- (void)collectionMenuViewDidEnterEditingMode:(TGCollectionMenuView *)__unused collectionMenuView
{
    if (!_editingMode)
    {
        _editingMode = true;
        
        [self didEnterEditingMode:true];
    }
}

- (void)collectionMenuViewDidLeaveEditingMode:(TGCollectionMenuView *)__unused collectionMenuView
{
    if (_editingMode)
    {
        _editingMode = false;
        
        [self didLeaveEditingMode:true];
    }
}

- (NSIndexPath *)indexPathForItem:(TGCollectionItem *)item
{
    int sectionIndex = -1;
    
    for (TGCollectionMenuSection *section in _menuSections.sections)
    {
        sectionIndex++;
        
        int itemIndex = -1;
        
        for (TGCollectionItem *listItem in section.items)
        {
            itemIndex++;
            
            if (listItem == item)
            {
                return [NSIndexPath indexPathForItem:itemIndex inSection:sectionIndex];
            }
        }
    }
    
    return nil;
}

- (NSUInteger)indexForSection:(TGCollectionMenuSection *)section
{
    int index = -1;
    for (TGCollectionMenuSection *listSection in _menuSections.sections)
    {
        index++;
        
        if (listSection == section)
            return (NSUInteger)index;
    }
    
    return NSNotFound;
}

- (void)loadView
{
    [super loadView];
    
    self.view.backgroundColor = [TGInterfaceAssets listsBackgroundColor];
    
    _headerBackgroundView = [[UIView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, self.view.frame.size.width, self.controllerInset.top)];
    _headerBackgroundView.backgroundColor = [UIColor whiteColor];
    [self.view addSubview:_headerBackgroundView];
    
    [self _resetCollectionView];
    
    [self setExplicitTableInset:UIEdgeInsetsMake(-(TGIsRetina() ? 0.5f : 1.0f), 0, 0, 0)];
    if (![self _updateControllerInset:false])
        [self controllerInsetUpdated:UIEdgeInsetsZero];
}

#pragma mark -

- (void)controllerInsetUpdated:(UIEdgeInsets)previousInset
{
    [super controllerInsetUpdated:previousInset];
    
    if ([self isViewLoaded])
        _headerBackgroundView.frame = CGRectMake(0.0f, 0.0f, self.view.frame.size.width, self.controllerInset.top);
}

- (void)viewWillAppear:(BOOL)animated
{
    float currentLayoutWidth = [self inPopover] ? self.view.frame.size.width : [TGViewController screenSizeForInterfaceOrientation:self.interfaceOrientation].width;
    if (ABS(currentLayoutWidth - _currentLayoutWidth) > FLT_EPSILON)
    {
        _currentLayoutWidth = currentLayoutWidth;
        [_collectionLayout invalidateLayout];
    }
    
    for (NSIndexPath *indexPath in [_collectionView indexPathsForSelectedItems])
    {
        [_collectionView deselectItemAtIndexPath:indexPath animated:animated];
    }
    
    [super viewWillAppear:animated];
}

- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
    //CGFloat currentLayoutWidth = [self inPopover] ? self.view.frame.size.width : [TGViewController screenSizeForInterfaceOrientation:toInterfaceOrientation].width;
    //if (ABS(_currentLayoutWidth - currentLayoutWidth) > FLT_EPSILON)
    [_collectionLayout invalidateLayout];
    
    [super willRotateToInterfaceOrientation:toInterfaceOrientation duration:duration];
}

- (void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
    [super willAnimateRotationToInterfaceOrientation:toInterfaceOrientation duration:duration];
}

- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView
{
    if (collectionView == _collectionView)
        return _menuSections.sections.count;
    
    return 0;
}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
    if (collectionView == _collectionView && section < (NSInteger)_menuSections.sections.count)
        return ((TGCollectionMenuSection *)_menuSections.sections[section]).items.count;
    return 0;
}

- (UICollectionViewCell *)collectionView:(TGCollectionMenuView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
    TGCollectionItem *item = indexPath.section < (NSInteger)_menuSections.sections.count && indexPath.row < (NSInteger)((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items.count ? ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item] : nil;
    
    if (item != nil)
    {
        TGCollectionItemView *itemView = [item dequeueItemView:collectionView registeredIdentifiers:_collectionRegisteredIdentifiers forIndexPath:indexPath];
        if (itemView.boundItem != nil)
            [itemView.boundItem unbindView];
        
        TGCollectionItem *previousItem = nil;
        if (indexPath.item > 0)
            previousItem = ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item - 1];
        
        TGCollectionItem *nextItem = nil;
        if (indexPath.item < (NSInteger)((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items.count - 1)
            nextItem = ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item + 1];
        
        int itemPositionMask = 0;
        if (!item.transparent)
        {
            if (previousItem == nil || previousItem.transparent)
                itemPositionMask |= TGCollectionItemViewPositionFirstInBlock;
            
            if (nextItem == nil || nextItem.transparent)
                itemPositionMask |= TGCollectionItemViewPositionLastInBlock;
            
            if (itemPositionMask == 0)
                itemPositionMask = TGCollectionItemViewPositionMiddleInBlock;
        }
        
        [itemView setItemPosition:itemPositionMask];
        [item bindView:itemView];
        
        [collectionView setupCellForEditing:itemView];
        
        return itemView;
    }
    
    return [collectionView dequeueReusableCellWithReuseIdentifier:@"_empty" forIndexPath:indexPath];
}

- (void)collectionView:(UICollectionView *)__unused collectionView didEndDisplayingCell:(TGCollectionItemView *)cell forItemAtIndexPath:(NSIndexPath *)__unused indexPath
{
    [cell.boundItem unbindView];
}

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)__unused collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
    TGCollectionItem *item = indexPath.section < (NSInteger)_menuSections.sections.count && indexPath.row < (NSInteger)((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items.count ? ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item] : nil;
    
    CGSize layoutSize = collectionView.frame.size;
    if ([self inPopover])
        layoutSize.width = 320.0f;
    else if ([self inFormSheet])
        layoutSize.width = 540.0f;
    
    if (item != nil)
        return [item itemSizeForContainerSize:layoutSize];
    
    return CGSizeZero;
}

- (CGFloat)collectionView:(UICollectionView *)__unused collectionView layout:(UICollectionViewLayout *)__unused collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)__unused section
{
    return 0.0f;
}

- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)__unused collectionViewLayout insetForSectionAtIndex:(NSInteger)section
{
    if (collectionView == _collectionView)
    {
        
        return ((TGCollectionMenuSection *)_menuSections.sections[section]).insets;
    }
    
    return UIEdgeInsetsZero;
}

- (BOOL)collectionView:(UICollectionView *)collectionView shouldHighlightItemAtIndexPath:(NSIndexPath *)indexPath
{
    if (collectionView == _collectionView)
    {
        TGCollectionItem *item = indexPath.section < (NSInteger)_menuSections.sections.count && indexPath.row < (NSInteger)((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items.count ? ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item] : nil;
        if (item != nil)
            return item.highlightable;
    }
    
    return false;
}

- (BOOL)collectionView:(UICollectionView *)collectionView shouldSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
    if (collectionView == _collectionView)
    {
        TGCollectionItem *item = indexPath.section < (NSInteger)_menuSections.sections.count && indexPath.row < (NSInteger)((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items.count ? ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item] : nil;
        if (item != nil)
            return item.selectable;
    }
    
    return false;
}

- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
    if (collectionView == _collectionView)
    {
        TGCollectionItem *item = indexPath.section < (NSInteger)_menuSections.sections.count && indexPath.row < (NSInteger)((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items.count ? ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item] : nil;
        if (item != nil)
        {
            if (item.deselectAutomatically)
                [collectionView deselectItemAtIndexPath:indexPath animated:true];
            
            [item itemSelected:self];
        }
    }
}

- (BOOL)collectionView:(UICollectionView *)collectionView shouldShowMenuForItemAtIndexPath:(NSIndexPath *)indexPath
{
    if (collectionView == _collectionView)
    {
        TGCollectionItem *item = indexPath.section < (NSInteger)_menuSections.sections.count && indexPath.row < (NSInteger)((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items.count ? ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item] : nil;
        if (item != nil)
        {
            return [item itemWantsMenu];
        }
    }
    
    return false;
}

- (BOOL)collectionView:(UICollectionView *)collectionView canPerformAction:(SEL)action forItemAtIndexPath:(NSIndexPath *)indexPath withSender:(id)__unused sender
{
    if (collectionView == _collectionView)
    {
        TGCollectionItem *item = indexPath.section < (NSInteger)_menuSections.sections.count && indexPath.row < (NSInteger)((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items.count ? ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item] : nil;
        if (item != nil)
        {
            return [item itemCanPerformAction:action];
        }
    }
    
    return false;
}

- (void)collectionView:(UICollectionView *)collectionView performAction:(SEL)action forItemAtIndexPath:(NSIndexPath *)indexPath withSender:(id)__unused sender
{
    if (collectionView == _collectionView)
    {
        TGCollectionItem *item = indexPath.section < (NSInteger)_menuSections.sections.count && indexPath.row < (NSInteger)((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items.count ? ((TGCollectionMenuSection *)_menuSections.sections[indexPath.section]).items[indexPath.item] : nil;
        if (item != nil)
        {
            return [item itemPerformAction:action];
        }
    }
}

@end