//
//  ThumbnailProvider.m
//  PanoThumb
//
//  Created by Omar Mohamed Ali Mudhir on 15/06/18.
//  Copyright © 2018 OmixLab ltd. All rights reserved.
//

#import "ThumbnailProvider.h"

@implementation ThumbnailProvider

- (void)provideThumbnailForFileRequest:(QLFileThumbnailRequest *)request completionHandler:(void (^)(QLThumbnailReply * _Nullable, NSError * _Nullable))handler {
    
    // There are three ways to provide a thumbnail through a QLThumbnailReply. Only one of them should be used.
    /*

    // First way: Draw the thumbnail into the current context, set up with UIKit's coordinate system.
    handler([QLThumbnailReply replyWithContextSize:request.maximumSize currentContextDrawingBlock:^BOOL {
        // Draw the thumbnail here.
        // Return YES if the thumbnail was successfully drawn inside this block.
        return YES;
    }], nil);
*/
    
    // Second way: Draw the thumbnail into a context passed to your block, set up with Core Graphics' coordinate system.
    
    CGRect r = CGRectMake(0, 0, 128, 128);
    
    handler([QLThumbnailReply replyWithContextSize:r.size drawingBlock:^BOOL(CGContextRef  _Nonnull context) {
        // Draw the thumbnail here.

        NSLog(@"thumbnail generated");
        NSURL* u = [request fileURL];
        FILE* fp = fopen([u fileSystemRepresentation], "rb");
        if (fp)
        {
            int h[3];
            fread(h, sizeof(int), 3, fp);

            //uint8_t* data = (uint8_t*)malloc(h[0]*h[1]*h[2]);
            CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
            CGContextRef bmp = CGBitmapContextCreate(NULL, h[0], h[1], 8, h[0]*h[2], colorSpace, kCGImageAlphaPremultipliedLast);
            uint8_t* data = CGBitmapContextGetData(bmp);
            fread(data, h[0]*h[1]*h[2], 1, fp);
            fclose(fp);
     
            CGImageRef img = CGBitmapContextCreateImage(bmp);
            CGRect r2 = CGRectMake(0, 0, 128*request.scale, 128*request.scale);
            CGContextDrawImage(context, r2, img);
        }

        // Return YES if the thumbnail was successfully drawn inside this block.
        return YES;
    }], nil);
  /*
    // Third way: Set an image file URL.
    handler([QLThumbnailReply replyWithImageFileURL:[NSBundle.mainBundle URLForResource:@"fileThumbnail" withExtension:@"jpg"]], nil);
    
    */
}

@end