/**
 * Copyright (c) 2015-present, Horcrux.
 * All rights reserved.
 *
 * This source code is licensed under the MIT-style license found in the
 * LICENSE file in the root directory of this source tree.
 */

#import "RCTConvert+RNSVG.h"

#import <React/RCTFont.h>
#import <React/RCTLog.h>
#import "RNSVGContextBrush.h"
#import "RNSVGPainterBrush.h"
#import "RNSVGSolidColorBrush.h"

NSRegularExpression *RNSVGDigitRegEx;

@implementation RCTConvert (RNSVG)

RCT_ENUM_CONVERTER(
    RNSVGCGFCRule,
    (@{
      @"evenodd" : @(kRNSVGCGFCRuleEvenodd),
      @"nonzero" : @(kRNSVGCGFCRuleNonzero),
    }),
    kRNSVGCGFCRuleNonzero,
    intValue)

RCT_ENUM_CONVERTER(
    RNSVGVBMOS,
    (@{@"meet" : @(kRNSVGVBMOSMeet), @"slice" : @(kRNSVGVBMOSSlice), @"none" : @(kRNSVGVBMOSNone)}),
    kRNSVGVBMOSMeet,
    intValue)

RCT_ENUM_CONVERTER(
    RNSVGUnits,
    (@{
      @"objectBoundingBox" : @(kRNSVGUnitsObjectBoundingBox),
      @"userSpaceOnUse" : @(kRNSVGUnitsUserSpaceOnUse),
    }),
    kRNSVGUnitsObjectBoundingBox,
    intValue)

+ (RNSVGBrush *)RNSVGBrush:(id)json
{
  if ([json isKindOfClass:[NSNumber class]]) {
    return [[RNSVGSolidColorBrush alloc] initWithNumber:json];
  }
  if ([json isKindOfClass:[NSString class]]) {
    NSString *value = [self NSString:json];
    if (!RNSVGDigitRegEx) {
      RNSVGDigitRegEx = [NSRegularExpression regularExpressionWithPattern:@"[0-9.-]+"
                                                                  options:NSRegularExpressionCaseInsensitive
                                                                    error:nil];
    }
    NSArray<NSTextCheckingResult *> *_matches = [RNSVGDigitRegEx matchesInString:value
                                                                         options:0
                                                                           range:NSMakeRange(0, [value length])];
    NSMutableArray<NSNumber *> *output = [NSMutableArray array];
    NSUInteger i = 0;
    [output addObject:[NSNumber numberWithInteger:0]];
    for (NSTextCheckingResult *match in _matches) {
      NSString *strNumber = [value substringWithRange:match.range];
      [output addObject:[NSNumber numberWithDouble:(i++ < 3 ? strNumber.doubleValue / 255 : strNumber.doubleValue)]];
    }
    if ([output count] < 5) {
      [output addObject:[NSNumber numberWithDouble:1]];
    }
    return [[RNSVGSolidColorBrush alloc] initWithArray:output];
  }
  NSDictionary *dict = [self NSDictionary:json];
  int type = [dict[@"type"] intValue];

  switch (type) {
    case 0: // solid color
            // These are probably expensive allocations since it's often the same value.
            // We should memoize colors but look ups may be just as expensive.
    {
      NSArray *arr = @[ @(0), dict[@"payload"] ];
      return [[RNSVGSolidColorBrush alloc] initWithArray:arr];
    }
    case 1: // brush
    {
      NSArray *arr = @[ @(1), dict[@"brushRef"] ];
      return [[RNSVGPainterBrush alloc] initWithArray:arr];
    }
    case 2: // currentColor
      return [[RNSVGBrush alloc] initWithArray:nil];
    case 3: // context-fill
      return [[RNSVGContextBrush alloc] initFill];
    case 4: // context-stroke
      return [[RNSVGContextBrush alloc] initStroke];
    default:
      RCTLogError(@"Unknown brush type: %zd", (unsigned long)type);
      return nil;
  }
}

+ (RNSVGPathParser *)RNSVGCGPath:(NSString *)d
{
  return [[RNSVGPathParser alloc] initWithPathString:d];
}

+ (RNSVGLength *)RNSVGLength:(id)json
{
  if ([json isKindOfClass:[NSNumber class]]) {
    return [RNSVGLength lengthWithNumber:(CGFloat)[json doubleValue]];
  } else if ([json isKindOfClass:[NSString class]]) {
    NSString *stringValue = (NSString *)json;
    return [RNSVGLength lengthWithString:stringValue];
  } else {
    return [[RNSVGLength alloc] init];
  }
}

+ (NSArray<RNSVGLength *> *)RNSVGLengthArray:(id)json
{
  if ([json isKindOfClass:[NSNumber class]]) {
    RNSVGLength *length = [RNSVGLength lengthWithNumber:(CGFloat)[json doubleValue]];
    return [NSArray arrayWithObject:length];
  } else if ([json isKindOfClass:[NSArray class]]) {
    NSArray *arrayValue = (NSArray *)json;
    NSMutableArray<RNSVGLength *> *lengths = [NSMutableArray arrayWithCapacity:[arrayValue count]];
    for (id obj in arrayValue) {
      [lengths addObject:[self RNSVGLength:obj]];
    }
    return lengths;
  } else if ([json isKindOfClass:[NSString class]]) {
    NSString *stringValue = (NSString *)json;
    RNSVGLength *length = [RNSVGLength lengthWithString:stringValue];
    return [NSArray arrayWithObject:length];
  } else {
    return nil;
  }
}

+ (CGRect)RNSVGCGRect:(id)json offset:(NSUInteger)offset
{
  NSArray *arr = [self NSArray:json];
  if (arr.count < offset + 4) {
    RCTLogError(@"Too few elements in array (expected at least %zd): %@", (ssize_t)(4 + offset), arr);
    return CGRectZero;
  }
  return (CGRect){
      {[self CGFloat:arr[offset]], [self CGFloat:arr[offset + 1]]},
      {[self CGFloat:arr[offset + 2]], [self CGFloat:arr[offset + 3]]},
  };
}

+ (RNSVGColor *)RNSVGColor:(id)json offset:(NSUInteger)offset
{
  NSArray *arr = [self NSArray:json];
  if (arr.count == offset + 1) {
    return [self RNSVGColor:[arr objectAtIndex:offset]];
  }
  if (arr.count < offset + 4) {
    RCTLogError(@"Too few elements in array (expected at least %zd): %@", (ssize_t)(4 + offset), arr);
    return nil;
  }
  return [self RNSVGColor:[arr subarrayWithRange:(NSRange){offset, 4}]];
}

+ (CGGradientRef)RNSVGCGGradient:(id)json
{
  NSArray *arr = [self NSArray:json];
  NSUInteger count = arr.count / 2;
  NSUInteger values = count * 5;
  NSUInteger offsetIndex = values - count;
  CGFloat colorsAndOffsets[values];
  for (NSUInteger i = 0; i < count; i++) {
    NSUInteger stopIndex = i * 2;
    CGFloat offset = (CGFloat)[arr[stopIndex] doubleValue];
    NSUInteger argb = [self NSUInteger:arr[stopIndex + 1]];

    CGFloat a = ((argb >> 24) & 0xFF) / 255.0;
    CGFloat r = ((argb >> 16) & 0xFF) / 255.0;
    CGFloat g = ((argb >> 8) & 0xFF) / 255.0;
    CGFloat b = (argb & 0xFF) / 255.0;

    NSUInteger colorIndex = i * 4;
    colorsAndOffsets[colorIndex] = r;
    colorsAndOffsets[colorIndex + 1] = g;
    colorsAndOffsets[colorIndex + 2] = b;
    colorsAndOffsets[colorIndex + 3] = a;

    colorsAndOffsets[offsetIndex + i] = fmax(0, fmin(offset, 1));
  }

  CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();
  CGGradientRef gradient =
      CGGradientCreateWithColorComponents(rgb, colorsAndOffsets, colorsAndOffsets + offsetIndex, count);
  CGColorSpaceRelease(rgb);
  return (CGGradientRef)CFAutorelease(gradient);
}

@end