/*
 * This file is part of libsidplayfp, a SID player engine.
 *
 * Copyright 2012-2013 Leandro Nini <drfiemost@users.sourceforge.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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

#ifndef ROMCHECK_H
#define ROMCHECK_H

#include <stdint.h>
#include <map>
#include <string>
#include <utility>

#include "sidmd5.h"

namespace libsidplayfp
{

/**
 * Utility class to identify known ROM images through their md5 checksum.
 */
class romCheck
{
private:
    typedef std::map<std::string, const char*> md5map;

private:
    /**
     * Maps checksums to respective ROM description.
     * Must be filled by derived class.
     */
    md5map m_checksums;

    /**
     * Pointer to the ROM buffer
     */ 
    const uint8_t* m_rom;

    /**
     * Size of the ROM buffer.
     */
    unsigned int m_size;

private:
    romCheck();

    /**
     * Calculate the md5 digest.
     */
    std::string checksum() const
    {
        try
        {
            sidmd5 md5;
            md5.append(m_rom, m_size);
            md5.finish();

            return md5.getDigest();
        }
        catch (md5Error const &)
        {
            return std::string();
        }
    }

protected:
    /**
     * Construct the class.
     *
     * @param rom pointer to the ROM buffer
     * @param size size of the ROM buffer
     */
    romCheck(const uint8_t* rom, int size) :
        m_rom(rom),
        m_size(size) {}

    void add(const char* md5, const char* desc)
    {
        m_checksums.insert(std::make_pair(md5, desc));
    }

public:
    /**
     * Get ROM description.
     *
     * @return the ROM description or "Unknown Rom".
     */
    const char* info() const
    {
        md5map::const_iterator res = m_checksums.find(checksum());
        return (res != m_checksums.end()) ? res->second : "Unknown Rom";
    }
};

/**
 * romCheck implementation specific for kernal ROM.
 */
class kernalCheck : public romCheck
{
public:
    kernalCheck(const uint8_t* kernal) :
        romCheck(kernal, 0x2000)
    {
        add("1ae0ea224f2b291dafa2c20b990bb7d4", "C64 KERNAL first revision");
        add("7360b296d64e18b88f6cf52289fd99a1", "C64 KERNAL second revision");
        add("479553fd53346ec84054f0b1c6237397", "C64 KERNAL second revision (Japanese)");
        add("39065497630802346bce17963f13c092", "C64 KERNAL third revision");
        add("27e26dbb267c8ebf1cd47105a6ca71e7", "C64 KERNAL third revision (Swedish)");
        add("187b8c713b51931e070872bd390b472a", "Commodore SX-64 KERNAL");
        add("b7b1a42e11ff8efab4e49afc4faedeee", "Commodore SX-64 KERNAL (Swedish)");
        add("3abc938cac3d622e1a7041c15b928707", "Cockroach Turbo-ROM");
        add("631ea2ca0dcda414a90aeefeaf77fe45", "Cockroach Turbo-ROM (SX-64)");
        add("a9de1832e9be1a8c60f4f979df585681", "Datel DOS-ROM 1.2");
        add("da43563f218b46ece925f221ef1f4bc2", "Datel Mercury 3 (NTSC)");
        add("b7dc8ed82170c81773d4f5dc8069a000", "Datel Turbo ROM II (PAL)");
        add("6b309c76473dcf555c52c598c6a51011", "Dolphin DOS v1.0");
        add("c3c93b9a46f116acbfe7ee147c338c60", "Dolphin DOS v2.0-1 AU");
        add("2a441f4abd272d50f94b43c7ff3cc629", "Dolphin DOS v2.0-1");
        add("c7a175217e67dcb425feca5fcf2a01cc", "Dolphin DOS v2.0-2");
        add("7a9b1040cfbe769525bb9cdc28427be6", "Dolphin DOS v2.0-3");
        add("fc8fb5ec89b34ae41c8dc20907447e06", "Dolphin DOS v3.0");
        add("9a6e1c4b99c6f65323aa96940c7eb7f7", "ExOS v3 fertig");
        add("3241a4fcf2ba28ba3fc79826bc023814", "ExOS v3");
        add("cffd2616312801da56bcc6728f0e39ca", "ExOS v4");
        add("e6e2bb24a0fa414182b0fd149bde689d", "TurboAccess");
        add("c5c5990f0826fcbd372901e761fab1b7", "TurboTrans v3.0-1");
        add("042ffc11383849bdf0e600474cefaaaf", "TurboTrans v3.0-2");
        add("9d62852013fc2c29c3111c765698664b", "Turbo-Process US");
        add("f9c9838e8d6752dc6066a8c9e6c2e880", "Turbo-Process");
    }
};

/**
 * romCheck implementation specific for basic ROM.
 */
class basicCheck : public romCheck
{
public:
    basicCheck(const uint8_t* basic) :
        romCheck(basic, 0x2000)
    {
        add("57af4ae21d4b705c2991d98ed5c1f7b8", "C64 BASIC V2");
    }
};

/**
 * romCheck implementation specific for character generator ROM.
 */
class chargenCheck : public romCheck
{
public:
    chargenCheck(const uint8_t* chargen) :
        romCheck(chargen, 0x1000)
    {
        add("12a4202f5331d45af846af6c58fba946", "C64 character generator");
        add("cf32a93c0a693ed359a4f483ef6db53d", "C64 character generator (Japanese)");
    }
};

}

#endif // ROMCHECK_H