/*	EQEMu: Everquest Server Emulator
	Copyright (C) 2001-2010 EQEMu Development Team (http://eqemulator.net)

	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; version 2 of the License.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY except by those people which sell it, which
	are required to give you total support for your newly bought product;
	without even the implied warranty of MERCHANTABILITY or FITNESS FOR
	A PARTICULAR PURPOSE. See the GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "../common/debug.h"
#include "Encryption.h"
#include "ErrorLog.h"
#include <string>

extern ErrorLog *server_log;

bool Encryption::LoadCrypto(std::string name)
{
	if(!Load(name.c_str()))
	{
		server_log->Log(log_error, "Failed to load %s from the operating system.", name.c_str());
		return false;
	}
	else
	{
		encrypt_func = (DLLFUNC_Encrypt)GetSym("Encrypt");
		if(encrypt_func == NULL)
		{
			server_log->Log(log_error, "Failed to attach Encrypt.");
			Unload();
			return false;
		}
		decrypt_func = (DLLFUNC_DecryptUsernamePassword)GetSym("DecryptUsernamePassword");
		if(decrypt_func == NULL)
		{
			server_log->Log(log_error, "Failed to attach DecryptUsernamePassword.");
			Unload();
			return false;
		}
		delete_func = (DLLFUNC_HeapDelete)GetSym("_HeapDeleteCharBuffer");
		if(delete_func == NULL)
		{
			server_log->Log(log_error, "Failed to attach _HeapDeleteCharBuffer.");
			Unload();
			return false;
		}
	}
	return true;
}

char *Encryption::DecryptUsernamePassword(const char* encrypted_buffer, unsigned int buffer_size, int mode)
{
	if(decrypt_func)
	{
		return decrypt_func(encrypted_buffer, buffer_size, mode);
	}
	return NULL;
}

char *Encryption::Encrypt(const char* buffer, unsigned int buffer_size, unsigned int &out_size)
{
	if(encrypt_func)
	{
		return encrypt_func(buffer, buffer_size, out_size);
	}
	return NULL;
}

void Encryption::DeleteHeap(char *buffer)
{
	if(delete_func)
	{
		delete_func(buffer);
	}
}

bool Encryption::Load(const char *name)
{
	SetLastError(0);
#ifdef UNICODE
	int name_length = strlen(name);
	int wide_length = MultiByteToWideChar(CP_ACP, 0, name, name_length+1, 0, 0);
	WCHAR *wide_string = new WCHAR[wide_length];
	MultiByteToWideChar(CP_ACP, 0, name, name_length+1, wide_string, wide_length);

	h_dll = LoadLibrary(wide_string);
	delete[] wide_string;
#else
	h_dll = LoadLibrary(name);
#endif

	if(h_dll == NULL)
	{
		return false;
	}
	else
	{
		SetLastError(0);
	}

	return true;
}

void Encryption::Unload()
{
	if(h_dll)
	{
		FreeLibrary(h_dll);
		h_dll = NULL;
	}
}

bool Encryption::GetSym(const char *name, void **sym)
{
	if(Loaded())
	{
		*sym = GetProcAddress(h_dll, name);
		return(*sym != NULL);
	}
	else
	{
		return false;
	}
}

void *Encryption::GetSym(const char *name)
{
	if(Loaded())
	{
		return GetProcAddress(h_dll, name);
	}
	else
	{
		return NULL;
	}
}