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@implementation JSbdecoder
- (NSDictionary *) decodeTorrentFileData: (NSData *) torrentFileData {
    self.rawTorrentData = [torrentFileData bytes];
    self.torrentData = torrentFileData;
    self.position = 0;
    
    
    return [NSDictionary dictionaryWithDictionary: [self convertDictionaryDataToStrings:[[NSArray arrayWithArray:[self bdecodeData]] objectAtIndex: 0]]];
}

- (NSArray *) bdecodeData {
    NSMutableArray *methodArray = [NSMutableArray array];
    do{
        if(self.rawTorrentData[self.position] == 'i') {
            self.position++;
            [methodArray addObject:[self decodeInt]];
        } else if(self.rawTorrentData[self.position] == 'l') {
            self.position++;
            [methodArray addObject:[self decodeList]];
        } else if(self.rawTorrentData[self.position] == 'd') {
            self.position++;
            [methodArray addObject:[self decodeDictionary]];
        } else if(isdigit(self.rawTorrentData[self.position])) {
            [methodArray addObject:[self decodeBytes]];
        } else if(self.rawTorrentData[self.position] == 'e') {
            self.position++;
            //Should only hit this when at the end of lists or dictionaries.
            break;
        } else {
            NSLog(@"Error decoding torrent. Unexpected character '%c' at position %d.", self.rawTorrentData[self.position], self.position);
            exit(0);
        }
    } while(self.position < [self.torrentData length]);
    
    return [NSArray arrayWithArray: methodArray];
}


- (NSNumber *) decodeInt {
    uint32 methodPosition = self.position;
    while(self.rawTorrentData[self.position] != 'e') {
       self.position++; 
    }
    self.position++;
    return [NSNumber numberWithInteger: [[NSString stringWithUTF8String: [[self.torrentData subdataWithRange: NSMakeRange(methodPosition, (self.position - methodPosition))] bytes]] integerValue]];
}

- (NSData *) decodeBytes {
    uint32 methodPosition = self.position;
    while(self.rawTorrentData[self.position] != ':') {
        self.position++;
    }
    NSUInteger bytesLength = [[NSString stringWithUTF8String: [[self.torrentData subdataWithRange: NSMakeRange(methodPosition, (self.position - methodPosition))] bytes]] integerValue];
    self.position++;
    methodPosition = self.position;
    self.position += bytesLength;
    
    return [NSData dataWithData: [self.torrentData subdataWithRange: NSMakeRange(methodPosition, bytesLength)]];
}

- (NSArray *) decodeList {
    
    return [NSArray arrayWithArray:[self bdecodeData]];
}

- (NSDictionary *) decodeDictionary {
    NSMutableDictionary *methodDictionary = [NSMutableDictionary dictionary];
    NSArray *methodArray = [NSArray arrayWithArray:[self bdecodeData]];
    for(NSUInteger i = 0; i < [methodArray count]; i += 2) {
        [methodDictionary setObject: [methodArray objectAtIndex: i + 1] forKey: [methodArray objectAtIndex: i]];
    }
    
    return [NSDictionary dictionaryWithDictionary: methodDictionary];
}