VRTUIImageWrapper.m

//
//  VRTUIImageWrapper.m
//  ViroReact
//
//  Created by Vik Advani on 3/20/17.
//  Copyright © 2017 Viro Media. All rights reserved.
//

#import "VRTUIImageWrapper.h"
#import <React/RCTUtils.h>
#import <React/RCTImageSource.h>


@implementation VRTUIImageWrapper
@end

@implementation RCTConvert (VRTUIImageWrapper)

// Copied over from +(UIImage)RCTConvert in React, modified method to allow for https and http urls that
// aren not tied to the packager.
+ (VRTUIImageWrapper *)VRTUIImageWrapper:(id)json {
  if (!json) {
    return nil;
  }
  
  RCTImageSource *imageSource = [RCTConvert RCTImageSource:json];
  if (!imageSource) {
    return nil;
  }
  
  __block UIImage *image;
  if (!RCTIsMainQueue()) {
    // It seems that none of the UIImage loading methods can be guaranteed
    // thread safe, so we'll pick the lesser of two evils here and block rather
    // than run the risk of crashing
    RCTLogWarn(@"Calling [RCTConvert UIImage:] on a background thread is not recommended");
    dispatch_sync(dispatch_get_main_queue(), ^{
      VRTUIImageWrapper *imageWrapper = [RCTConvert VRTUIImageWrapper:json];
      image = imageWrapper.image;
    });
    return image;
  }
  
  NSURL *URL = imageSource.request.URL;
  NSString *scheme = URL.scheme.lowercaseString;
  if ([scheme isEqualToString:@"file"]) {
    NSString *assetName = RCTBundlePathForURL(URL);
    image = assetName ? [UIImage imageNamed:assetName] : nil;
    if (!image) {
      // Attempt to load from the file system
      NSString *filePath = URL.path;
      if (filePath.pathExtension.length == 0) {
        filePath = [filePath stringByAppendingPathExtension:@"png"];
      }
      image = [UIImage imageWithContentsOfFile:filePath];
      if (!image) {
        RCTLogConvertError(json, @"an image. File not found.");
      }
    }
  } else if ([scheme isEqualToString:@"data"]) {
    image = [UIImage imageWithData:[NSData dataWithContentsOfURL:URL]];
  } else if ([scheme hasPrefix:@"http"]) {
    image = [UIImage imageWithData:[NSData dataWithContentsOfURL:URL]];
  } else {
    RCTLogConvertError(json, @"an image. Only local files or data URIs are supported.");
    return nil;
  }
  
  CGFloat scale = imageSource.scale;
  if (!scale && imageSource.size.width) {
    // If no scale provided, set scale to image width / source width
    scale = CGImageGetWidth(image.CGImage) / imageSource.size.width;
  }
  
  if (scale) {
    image = [UIImage imageWithCGImage:image.CGImage
                                scale:scale
                          orientation:image.imageOrientation];
  }
  
  if (!CGSizeEqualToSize(imageSource.size, CGSizeZero) &&
      !CGSizeEqualToSize(imageSource.size, image.size)) {
    RCTLogError(@"Image source %@ size %@ does not match loaded image size %@.",
                URL.path.lastPathComponent,
                NSStringFromCGSize(imageSource.size),
                NSStringFromCGSize(image.size));
  }
  
  VRTUIImageWrapper *uiImageWrapper = [[VRTUIImageWrapper alloc] init];
  uiImageWrapper.image = image;
  return uiImageWrapper;
}

@end