/* ***** BEGIN LICENSE BLOCK *****
*   Copyright (C) 2012-2014, Peter Hatina <phatina@gmail.com>
*
*   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, see <http://www.gnu.org/licenses/>.
* ***** END LICENSE BLOCK ***** */

#ifndef SHA1_HEADER
#define SHA1_HEADER

#include <iostream>
#include <string>

class SHA1
{
public:
    SHA1();
    void update(const std::string &s);
    void update(std::istream &is);
    std::string final();

    static std::string sumString(const std::string &str);

private:
    typedef unsigned long int uint32;   /* just needs to be at least 32bit */
    typedef unsigned long long uint64;  /* just needs to be at least 64bit */

    static const unsigned int DIGEST_INTS = 5;  /* number of 32bit integers per SHA1 digest */
    static const unsigned int BLOCK_INTS = 16;  /* number of 32bit integers per SHA1 block */
    static const unsigned int BLOCK_BYTES = BLOCK_INTS * 4;

    uint32 m_digest[DIGEST_INTS];
    std::string m_buffer;
    uint64 m_transforms;

    void reset();
    void transform(uint32 block[BLOCK_BYTES]);

    static void buffer_to_block(const std::string &buffer, uint32 block[BLOCK_BYTES]);
    static void read(std::istream &is, std::string &s, const int max);
};

#endif