/*
 * This file is part of the TrinityCore Project. See AUTHORS file for Copyright information
 *
 * 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/>.
 */

#include "cascfile.h"
#include <CascLib.h>
#include <cstdio>

CASCFile::CASCFile(std::shared_ptr<CASC::Storage const> casc, const char* filename, bool warnNoExist /*= true*/) :
    eof(false),
    buffer(nullptr),
    pointer(0),
    size(0)
{
    std::unique_ptr<CASC::File> file(casc->OpenFile(filename, CASC_LOCALE_ALL_WOW, false));
    if (!file)
    {
        if (warnNoExist || GetCascError() != ERROR_FILE_NOT_FOUND)
            fprintf(stderr, "Can't open %s: %s\n", filename, CASC::HumanReadableCASCError(GetCascError()));
        eof = true;
        return;
    }

    init(file.get(), filename);
}

CASCFile::CASCFile(std::shared_ptr<CASC::Storage const> casc, uint32 fileDataId, std::string const& description, bool warnNoExist /*= true*/) :
    eof(false),
    buffer(nullptr),
    pointer(0),
    size(0)
{
    std::unique_ptr<CASC::File> file(casc->OpenFile(fileDataId, CASC_LOCALE_ALL_WOW, false));
    if (!file)
    {
        if (warnNoExist || GetCascError() != ERROR_FILE_NOT_FOUND)
            fprintf(stderr, "Can't open %s: %s\n", description.c_str(), CASC::HumanReadableCASCError(GetCascError()));
        eof = true;
        return;
    }

    init(file.get(), description.c_str());
}

void CASCFile::init(CASC::File* file, const char* description)
{
    int64 fileSize = file->GetSize();
    if (fileSize == -1)
    {
        fprintf(stderr, "Can't open %s, failed to get size: %s!\n", description, CASC::HumanReadableCASCError(GetCascError()));
        eof = true;
        return;
    }

    size = fileSize;

    uint32 read = 0;
    buffer = new char[size];
    if (!file->ReadFile(buffer, size, &read) || size != read)
    {
        fprintf(stderr, "Can't read %s, size=%u read=%u: %s\n", description, uint32(size), uint32(read), CASC::HumanReadableCASCError(GetCascError()));
        eof = true;
        return;
    }
}

size_t CASCFile::read(void* dest, size_t bytes)
{
    if (eof)
        return 0;

    size_t rpos = pointer + bytes;
    if (rpos > size)
    {
        bytes = size - pointer;
        eof = true;
    }

    memcpy(dest, &(buffer[pointer]), bytes);

    pointer = rpos;

    return bytes;
}

void CASCFile::seek(int offset)
{
    pointer = offset;
    eof = (pointer >= size);
}

void CASCFile::seekRelative(int offset)
{
    pointer += offset;
    eof = (pointer >= size);
}

void CASCFile::close()
{
    delete[] buffer;
    buffer = nullptr;
    eof = true;
}