/*
  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation; either version
  2 of the License, or (at your option) any later version.
*/

#include <QString>
#include <QByteArray>
#include <QFileInfo>
#include <QFile>

#define CRYPTOPP_ENABLE_NAMESPACE_WEAK 1
#include <md5.h>
#include <files.h>
#include <filters.h>
#include <hex.h>

#include "helper.h"

namespace Helper {
	const QString mimeType(const QString &path){
		QString retval;
		magic_t mc = magic_open(MAGIC_MIME_TYPE);
		QByteArray name = path.toUtf8();
		if(mc){
			magic_load(mc, 0);
			const char* magic_c = magic_file(mc, name.constData());
			retval = QString(magic_c);
			magic_close(mc);
		}
		if(retval.toLower().startsWith("application/octet-stream")){
			magic_t mc = magic_open(MAGIC_NONE);
			if(mc){
				magic_load(mc, 0);
				const char* magic_c = magic_file(mc, name.constData());
				QString desc(magic_c);
				magic_close(mc);
				if(desc.toLower().contains("mpeg sequence") || desc.toLower().contains("microsoft asf")){
					retval = "video/";
				}
			}
			return retval;
		}
	}

	const QString md5Sum(const QString &path){
		QFileInfo info(path);
		if(!info.exists() || !info.isFile()){
			return QString();
		}

		using namespace CryptoPP;
		Weak::MD5 hash;
		std::string res;
		QString retval;
		if(info.size() < (5 * 1024 * 1024)){
			FileSource f(qPrintable(path), true, new HashFilter(hash, new HexEncoder(new StringSink(res))));
			retval = QString::fromStdString(res).toLower();
		}else{
			QFile file(path);
			file.open(QIODevice::ReadOnly);
			int offset = info.size() / 3;
			file.seek(offset);
			int numBytes = 512 * 1024;
			char *data = new char[numBytes];
			int read = file.read(data, numBytes);
			if(read != numBytes){
				delete [] data;
				return QString();
			}
			StringSource s((byte*)data, numBytes, true, new HashFilter(hash, new HexEncoder(new StringSink(res))));
			retval = QString::fromStdString(res).toLower();
			delete [] data;
		}
		return retval;
	}
}