Parse JSON content from a file.

parse-json.m

- ( NSArray * ) parseJSONContent : ( NSString * ) fileName
{
    NSArray * colors;
    NSArray * directories;
    NSData * buffer;
    NSError * error;
    NSFileHandle * handle;
    NSFileManager * manager;
    NSMutableString * path;
    NSString * blue;
    NSString * contents;
    NSString * green;
    NSString * red;
    
    manager = [NSFileManager defaultManager];
    
    directories = NSSearchPathForDirectoriesInDomains( NSDesktopDirectory, NSUserDomainMask, YES );
    path = [[NSMutableString alloc] initWithString : [directories objectAtIndex : 0]];
    [path appendString: @"/"];
    [path appendString: fileName];
    // NSLog( @"%@", path );
    
    if( [manager fileExistsAtPath : path] == NO )
    {
        NSLog( @"File not found." );
    } else {
        // NSLog( @"File exists." );
        
        // Handle
        handle = [NSFileHandle fileHandleForReadingAtPath : path];
        
        // Read NSData
        buffer = [handle readDataToEndOfFile];
        
        // To string
        contents = [[NSString alloc] initWithData : buffer encoding : NSUTF8StringEncoding];
        
        // Log contents
        NSLog( @"%@", contents );
        
        // Close file
        [handle closeFile];
        
        // Parse JSON content
        // Returns NSArray
        colors = [NSJSONSerialization JSONObjectWithData : buffer options : NSJSONReadingMutableContainers error : &error];
        
        if( !colors )
        {
            NSLog( @"Error parsing JSON: %@", error );
        } else {
            // Iterate over JSON values
            for( NSDictionary * item in colors )
            {
                red = [item valueForKey : @"red"];
                green = [item valueForKey : @"green"];
                blue = [item valueForKey : @"blue"];
                
                NSLog( @"Red: %@, Green: %@, Blue: %@", red, green, blue );
            }
        }
    }
    
    return colors;
}