#include "Swiften/Compress/ZLibCodecompressor.h"

#include <cassert>

#include "Swiften/Compress/ZLibException.h"

namespace Swift {

static const int CHUNK_SIZE = 1024; // If you change this, also change the unittest

ZLibCodecompressor::ZLibCodecompressor() {
	stream_.zalloc = Z_NULL;
	stream_.zfree = Z_NULL;
	stream_.opaque = Z_NULL;
}

ZLibCodecompressor::~ZLibCodecompressor() {
}

ByteArray ZLibCodecompressor::process(const ByteArray& input) {
	ByteArray output;
	stream_.avail_in = input.getSize();
	stream_.next_in = reinterpret_cast<Bytef*>(const_cast<char*>(input.getData()));
	int outputPosition = 0;
	do {
		output.resize(outputPosition + CHUNK_SIZE);
		stream_.avail_out = CHUNK_SIZE;
		stream_.next_out = reinterpret_cast<Bytef*>(output.getData() + outputPosition);
		int result = processZStream();
		if (result != Z_OK && result != Z_BUF_ERROR) {
			throw ZLibException(/* stream_.msg */);
		}
		outputPosition += CHUNK_SIZE;
	}
	while (stream_.avail_out == 0);
	if (stream_.avail_in != 0) {
		throw ZLibException();
	}
	output.resize(outputPosition - stream_.avail_out);
	return output;
}

}