/*

     File: FilterStack.m

 Abstract: A stack (not in LIFO sense) that manages available/active filters

  Version: 1.0

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 */

#import "FilterStack.h"

#import "CIFilter+FHAdditions.h"

NSString *const FilterStackActiveFilterListDidChangeNotification = @"FilterStackActiveFilterListDidChangeNotification";

static NSString *const kFilterSettingsKey = @"FilterSettings";

static NSString *const kFilterOrderKey = @"FilterOrder";

@implementation FilterDescriptor

@synthesize name = _name;

@synthesize displayName = _displayName;

@synthesize inputImageCount = _inputImageCount;

- (id)initWithName:(NSString *)name

{

    self = [super init];

    if (self) {

        CIFilter* f = [CIFilter filterWithName:name];

        if (f==nil)

        {

            self = nil;

            return nil;

        }

        _name = [name copy];

        _displayName = [[[f attributes] valueForKey:kCIAttributeFilterDisplayName] copy];

        _inputImageCount = (f.isSourceFilter) ? 0 : f.imageInputCount;

    }

    return self;

}

- (CIFilter*) filter

{

    return [CIFilter filterWithName:_name];

}

@end

@implementation SourceFilter

@synthesize inputImage;

- (CIImage *)outputImage

{

    if (inputImage==nil)

        return [CIImage emptyImage];

    return inputImage;

}

@end

@implementation SourceVideoFilter : SourceFilter

+ (NSDictionary *)customAttributes

{

    return @{ kCIAttributeFilterDisplayName : @"Input Video",

              kCIAttributeFilterCategories : @[kCICategoryVideo] };

}

@end

@implementation SourcePhotoFilter : SourceFilter

+ (NSDictionary *)customAttributes

{

    return @{ kCIAttributeFilterDisplayName : @"Input Photo",

              kCIAttributeFilterCategories : @[kCICategoryStillImage] };

}

@end

@implementation FilterStack

@synthesize activeFilters = _activeFilters;

@synthesize possibleNextFilters = _possibleNextFilters;

@synthesize sources = _sources;

@synthesize sourceCount = _sourceCount;

- (id)init

{

    self = [super init];

    if (self)

    {

        _sourceCount = 0;

        _activeFilters = [[NSArray alloc] init];

        _sources = [[NSMutableArray alloc] init];

        _nonsources = [[NSMutableArray alloc] init];

        FilterDescriptor *d;

        FilterDescriptor *video = [[FilterDescriptor alloc] initWithName:@"SourceVideoFilter"];

        [_sources addObject:video];

        FilterDescriptor *image = [[FilterDescriptor alloc] initWithName:@"SourcePhotoFilter"];

        [_sources addObject:image];

        for (NSString *name in [CIFilter filterNamesInCategory:kCICategoryBuiltIn])

        {

            CIFilter* f = [CIFilter filterWithName:name];

            if (f==nil | f.isUsableFilter == NO)

                continue;

            d = [[FilterDescriptor alloc] initWithName:name];

            if (f.imageInputCount == 0)

                [_sources addObject:d];

            else

                [_nonsources addObject:d];

        }

        // Add in custom filters here:

        NSArray* customFilters = @[ @"ChromaKey",

                                    @"ColorAccent",

                                    @"PixellatedPeople",

                                    @"TiltShift",

                                    @"OldeFilm",

                                    @"PixellateTransition",

                                    @"DistortionDemo",

                                    @"SobelEdgeH",

                                    @"SobelEdgeV"];

        for (NSString* f in customFilters)

        {

            d = [[FilterDescriptor alloc] initWithName:f];

            [_nonsources addObject:d];

        }

        _possibleNextFilters = [[NSMutableArray alloc] init];

    }

    return self;

}

- (void) _updateFilterList

{

    // Update sourceCount to reflect the number of active sources - i.e,

    // the number of filters that can be used as inputs to new filters

    NSUInteger sourceCount = 0;

    for (CIFilter *filter in _activeFilters)

    {

        for (NSString *attrName in [filter imageInputAttributeKeys])

        {

            if (!filter.isSourceFilter) {

                if (sourceCount > 0)

                    --sourceCount;

            }

        }

        ++sourceCount;

    }

    NSUInteger prevSourceCount = _sourceCount;

    _sourceCount = sourceCount;

    if (sourceCount != prevSourceCount)

    {

        NSMutableArray *newset = [[NSMutableArray alloc] init];

        for (FilterDescriptor* d in _nonsources)

            if (d.inputImageCount <= sourceCount)

                [newset addObject:d];

        _possibleNextFilters = newset;

    }

    [[NSNotificationCenter defaultCenter] postNotificationName:FilterStackActiveFilterListDidChangeNotification object:self];

}

- (BOOL)containsVideoSource

{

    for (CIFilter *filter in _activeFilters)

        if ([filter isKindOfClass:[SourceVideoFilter class]])

            return true;

    return false;

}

- (BOOL)containsPhotoSource

{

    for (CIFilter *filter in _activeFilters)

        if ([filter isKindOfClass:[SourcePhotoFilter class]])

            return true;

    return false;

}

- (void)appendFilter:(CIFilter *)filter

{

    _activeFilters = [_activeFilters arrayByAddingObject:filter];

    [self _updateFilterList];

}

- (void)removeLastFilter

{

    if (_activeFilters.count)

    {

        NSMutableArray *newActiveArray = [_activeFilters mutableCopy];

        [newActiveArray removeLastObject];

        _activeFilters = [newActiveArray copy];

        [self _updateFilterList];

    }

}

@end

static CGFloat gFSGlobalCropFilterMaxValue = INFINITY;

void FCSetGlobalCropFilterMaxValue(CGFloat max)

{

    gFSGlobalCropFilterMaxValue = max;

}

CGFloat FCGetGlobalCropFilterMaxValue(void)

{

    return gFSGlobalCropFilterMaxValue;

}