/*
    sram.cpp
    Copyright (C) 2007-2009 somebody
    Copyright (C) 2009 yellow wood goblin

    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 3 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 "sram.h"
#include <fat.h>
#include <malloc.h>
#include <string.h>
#include "exptools.h"
#include "language.h"
#include "progresswnd.h"

bool cSram::SaveFileName(const char* romName, char* saveName) {
    saveName[0] = 0;
    if (strlen(romName) > 251) return false;
    strcpy(saveName, romName);
    strcat(saveName, ".sav");
    return true;
}

void cSram::BlankSram(u16 aStartPage) {
    u8* buf = (u8*)malloc(SRAM_PAGE_SIZE);
    if (buf) {
        cExpansion::OpenNorWrite();
        memset(buf, 0, SRAM_PAGE_SIZE);
        for (u32 i = 0; i < SRAM_SAVE_PAGES; i++) {
            expansion().SetRampage(i + aStartPage);
            cExpansion::WriteSram(0x0A000000, buf, SRAM_PAGE_SIZE);
        }
        free(buf);
    }
    cExpansion::CloseNorWrite();
}

void cSram::LoadSramFromFile(const char* romName, u16 aStartPage) {
    char saveName[256];
    if (!SaveFileName(romName, saveName)) return;

    FILE* saveFile = fopen(saveName, "rb");
    if (saveFile) {
        sSaveInfo saveInfo;
        ProcessRAW(saveFile, saveInfo);
        u8* buf = (u8*)malloc(saveInfo.size);
        if (buf) {
            BlankSram(aStartPage);
            progressWnd().setTipText(LANG("progress window", "gba save load"));
            progressWnd().show();
            progressWnd().setPercent(0);
            memset(buf, 0, saveInfo.size);
            size_t ret = fread(buf, saveInfo.size, 1, saveFile);
            progressWnd().setPercent(10);
            if (ret == 1 && !ferror(saveFile)) {
                int page = saveInfo.offset / SRAM_PAGE_SIZE,
                    offset = saveInfo.offset % SRAM_PAGE_SIZE, size = saveInfo.size, bufOffset = 0,
                    ii = 0;
                while (page < SRAM_SAVE_PAGES && size > 0) {
                    expansion().SetRampage(page + aStartPage);
                    int maxSize = SRAM_PAGE_SIZE - offset,
                        bufSize = (size > maxSize) ? maxSize : size;
                    cExpansion::WriteSram(0x0A000000, buf + bufOffset, bufSize);
                    bufOffset += bufSize;
                    size -= bufSize;
                    offset = 0;
                    page++;
                    if (ii++ % 4 == 0)
                        progressWnd().setPercent(10 + bufOffset * 90 / saveInfo.size);
                }
            }
            progressWnd().setPercent(100);
            progressWnd().hide();
            free(buf);
        }
        fclose(saveFile);
        expansion().SetRampage(0);
    } else {
        BlankSram(aStartPage);
    }
}

void cSram::SaveSramToFile(const char* romName, u16 aStartPage) {
    char saveName[256];
    if (!SaveFileName(romName, saveName)) return;
    sSaveInfo saveInfo;
    FILE* saveFile = fopen(saveName, "rb");
    if (saveFile) {
        fread(&saveInfo, sizeof(saveInfo), 1, saveFile);
        if (saveInfo.marker != SAVE_GBA_HEADER_MAGIC)  // raw save
        {
            saveInfo.marker = SAVE_GBA_HEADER_MAGIC;
            saveInfo.offset = 0;
            fseek(saveFile, 0, SEEK_END);
            saveInfo.size = ftell(saveFile);
            saveInfo.header = 0;
        }
        fclose(saveFile);
        saveFile = NULL;
    }
    NormalizeSize(saveInfo);
    saveFile = fopen(saveName, "wb");
    if (saveFile) {
        fwrite(&saveInfo, sizeof(saveInfo), 1, saveFile);
        progressWnd().setTipText(LANG("progress window", "gba save store"));
        progressWnd().show();
        progressWnd().setPercent(0);
        u8* buf = SaveSramToMemory(aStartPage, saveInfo, true);
        if (buf) {
            fwrite(buf, saveInfo.size, 1, saveFile);
            free(buf);
        }
        progressWnd().setPercent(100);
        progressWnd().hide();
        fclose(saveFile);
    }
}

u8* cSram::SaveSramToMemory(u16 aStartPage, sSaveInfo& aSaveInfo, bool aShowProgress) {
    u8* buf = (u8*)malloc(aSaveInfo.size);
    if (buf) {
        cExpansion::OpenNorWrite();
        memset(buf, 0, aSaveInfo.size);

        int page = aSaveInfo.offset / SRAM_PAGE_SIZE, offset = aSaveInfo.offset % SRAM_PAGE_SIZE,
            size = aSaveInfo.size, bufOffset = 0, ii = 0;
        while (page < SRAM_SAVE_PAGES && size > 0) {
            expansion().SetRampage(page + aStartPage);
            int maxSize = SRAM_PAGE_SIZE - offset, bufSize = (size > maxSize) ? maxSize : size;
            cExpansion::ReadSram(0x0A000000, buf + bufOffset, bufSize);
            bufOffset += bufSize;
            size -= bufSize;
            offset = 0;
            page++;
            if (aShowProgress && ii++ % 4 == 0)
                progressWnd().setPercent(bufOffset * 90 / aSaveInfo.size);
        }
        cExpansion::CloseNorWrite();
    }
    return buf;
}

void cSram::CreateDefaultFile(const char* romName, u32 size) {
    char saveName[256];
    if (!SaveFileName(romName, saveName)) return;
    sSaveInfo saveInfo(size);
    NormalizeSize(saveInfo);
    FILE* saveFile = fopen(saveName, "rb");
    if (saveFile) {
        fclose(saveFile);
    } else {
        FILE* saveFile = fopen(saveName, "wb");
        if (saveFile) {
            fwrite(&saveInfo, sizeof(saveInfo), 1, saveFile);
            fclose(saveFile);
        }
    }
}

void cSram::NormalizeSize(sSaveInfo& anInfo) {
    if ((anInfo.offset + anInfo.size) > SRAM_SAVE_SIZE) {
        if (anInfo.offset <= SRAM_SAVE_SIZE) {
            anInfo.size = SRAM_SAVE_SIZE - anInfo.offset;
        } else {
            anInfo.size = 0;
        }
    }
}

void cSram::ProcessRAW(FILE* aFile, sSaveInfo& anInfo) {
    fread(&anInfo, sizeof(anInfo), 1, aFile);
    if (anInfo.marker != SAVE_GBA_HEADER_MAGIC)  // raw save
    {
        anInfo.marker = SAVE_GBA_HEADER_MAGIC;
        anInfo.offset = 0;
        fseek(aFile, 0, SEEK_END);
        anInfo.size = ftell(aFile);
        fseek(aFile, 0, SEEK_SET);
        anInfo.header = 0;
    }
    NormalizeSize(anInfo);
}