/*
 * functionrom.c
 *
 * Written by
 *  Andreas Boose <viceteam@t-online.de>
 *  Marco van den Heuvel <blackystardust68@yahoo.com>
 *
 * This file is part of VICE, the Versatile Commodore Emulator.
 * See README for copyright notice.
 *
 *  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., 59 Temple Place, Suite 330, Boston, MA
 *  02111-1307  USA.
 *
 */

#include "vice.h"

#include <stdio.h>
#include <string.h>

#include "archdep.h"
#include "bq4830y.h"
#include "c128mem.h"
#include "cmdline.h"
#include "functionrom.h"
#include "lib.h"
#include "resources.h"
#include "types.h"
#include "util.h"
#include "viciitypes.h"
#include "vicii-phi1.h"
#include "cartridge.h"
#include "c64cart.h"
#include "c64cartsystem.h"
#include "ltkernal.h"
#include "ramlink.h"

#define INTERNAL_FUNCTION_ROM_SIZE 0x8000

/* Flag: Do we enable the internal function ROM?  */
static int internal_function_rom_enabled;

/* Name of the internal function ROM.  */
static char *internal_function_rom_name = NULL;

/* Image of the internal function ROM.  */
uint8_t int_function_rom[INTERNAL_FUNCTION_ROM_SIZE];

/* Flag: Do we save RTC info when changed? */
static int internal_function_rtc_save;

/* Some prototypes are needed */
static int functionrom_load_internal(void);

/* bq4830y context */
static rtc_bq4830y_t *rtc1_context = NULL;

static int set_internal_function_rom_enabled(int val, void *param)
{
    if (internal_function_rom_enabled == val) {
        return 0;
    }

    switch (val) {
        case INT_FUNCTION_NONE:
        case INT_FUNCTION_ROM:
        case INT_FUNCTION_RAM:
        case INT_FUNCTION_RTC:
            break;
        default:
            return -1;
    }

    if (internal_function_rom_enabled == INT_FUNCTION_RTC && rtc1_context) {
        bq4830y_destroy(rtc1_context, internal_function_rtc_save);
        rtc1_context = NULL;
    }

    internal_function_rom_enabled = val;

    switch (val) {
        case INT_FUNCTION_RTC:
            rtc1_context = bq4830y_init("IFR");
            /* fall through */
        case INT_FUNCTION_RAM:
            memset(int_function_rom, 0, sizeof(int_function_rom));
            break;
        default:
            return functionrom_load_internal();
            break;
    }
    return 0;
}

static int set_internal_function_rtc_save(int val, void *param)
{
    internal_function_rtc_save = val ? 1 : 0;

    return 0;
}

static int set_internal_function_rom_name(const char *val, void *param)
{
    if (util_string_set(&internal_function_rom_name, val)) {
        return 0;
    }
    return functionrom_load_internal();
}


static const resource_string_t resources_string[] =
{
    { "InternalFunctionName", "", RES_EVENT_NO, NULL,
      &internal_function_rom_name,
      set_internal_function_rom_name, NULL },
    RESOURCE_STRING_LIST_END
};

static const resource_int_t resources_int[] =
{
    { "InternalFunctionROM", INT_FUNCTION_NONE, RES_EVENT_STRICT, (resource_value_t)0,
      &internal_function_rom_enabled,
      set_internal_function_rom_enabled, NULL },
    { "InternalFunctionROMRTCSave", 0, RES_EVENT_NO, NULL,
      &internal_function_rtc_save,
      set_internal_function_rtc_save, NULL },
    RESOURCE_INT_LIST_END
};

int functionrom_resources_init(void)
{
    if (resources_register_string(resources_string) < 0) {
        return -1;
    }
    return resources_register_int(resources_int);
}

void functionrom_resources_shutdown(void)
{
    if (rtc1_context) {
        bq4830y_destroy(rtc1_context, internal_function_rtc_save);
        rtc1_context = NULL;
    }
    lib_free(internal_function_rom_name);
}

static const cmdline_option_t cmdline_options[] =
{
    { "-intfrom", SET_RESOURCE, CMDLINE_ATTRIB_NEED_ARGS,
      NULL, NULL, "InternalFunctionName", NULL,
      "<Name>", "Specify name of internal Function ROM image" },
    { "-intfunc", SET_RESOURCE, CMDLINE_ATTRIB_NEED_ARGS,
      NULL, NULL, "InternalFunctionROM", NULL,
      "<Type>", "Type of internal Function ROM: (0: None, 1: ROM, 2: RAM, 3: RTC)" },
    { "-intfuncrtcsave", SET_RESOURCE, CMDLINE_ATTRIB_NONE,
      NULL, NULL, "InternalFunctionROMRTCSave", (resource_value_t)1,
      NULL, "Enable saving of the internal function RTC data when changed." },
    { "+intfuncrtcsave", SET_RESOURCE, CMDLINE_ATTRIB_NONE,
      NULL, NULL, "InternalFunctionROMRTCSave", (resource_value_t)0,
      NULL, "Disable saving of the internal function RTC data when changed." },
    CMDLINE_LIST_END
};

int functionrom_cmdline_options_init(void)
{
    return cmdline_register_options(cmdline_options);
}

static int functionrom_load_internal(void)
{
    if (internal_function_rom_enabled == INT_FUNCTION_ROM) {
        if (util_check_null_string(internal_function_rom_name)) {
            return 0;
        }
        /* try 32k first */
        if (util_file_load(internal_function_rom_name, int_function_rom,
                           INTERNAL_FUNCTION_ROM_SIZE, UTIL_FILE_LOAD_SKIP_ADDRESS) < 0) {
            /* try 16k */
            if (util_file_load(internal_function_rom_name, int_function_rom,
                            INTERNAL_FUNCTION_ROM_SIZE / 2, UTIL_FILE_LOAD_SKIP_ADDRESS) < 0) {
                return -1;
            } else {
                /* create a mirror */
                memcpy(&int_function_rom[INTERNAL_FUNCTION_ROM_SIZE / 2],
                    int_function_rom, INTERNAL_FUNCTION_ROM_SIZE / 2);
            }
        }
    } else if (internal_function_rom_enabled == INT_FUNCTION_NONE) {
        memset(int_function_rom, 0, sizeof(int_function_rom));
    }

    return 0;
}

uint8_t internal_function_rom_read(uint16_t addr)
{
    vicii.last_cpu_val = vicii_read_phi1();
    /* LTK MMU modification prioritises over internal function rom */
    if (cartridge_get_id(0) == CARTRIDGE_LT_KERNAL) {
        if (c128ltkernal_ram_read(addr, &(vicii.last_cpu_val))) {
            return vicii.last_cpu_val;
        }
    }
    /* RAMLINK ignores internal function ROMs somehow */
    if (cart_getid_slot0() == CARTRIDGE_RAMLINK) {
        if (c128ramlink_roml_read(addr, &(vicii.last_cpu_val))) {
            return vicii.last_cpu_val;
        }
    }
    if (internal_function_rom_enabled == INT_FUNCTION_RTC) {
        vicii.last_cpu_val = bq4830y_read(rtc1_context, (uint16_t)(addr & 0x7fff));
    } else if (internal_function_rom_enabled != INT_FUNCTION_NONE) {
        /* only do this if we are in ROM or RAM mode */
        vicii.last_cpu_val = int_function_rom[addr & (INTERNAL_FUNCTION_ROM_SIZE - 1)];
    }
    return vicii.last_cpu_val;
}

uint8_t internal_function_rom_peek(uint16_t addr)
{
    if (internal_function_rom_enabled == INT_FUNCTION_RTC) {
/* FIXME: this RTC should have a peek function */
/*        return bq4830y_peek(rtc1_context, (uint16_t)(addr & 0x7fff)); */
        return 0;
    }
    return int_function_rom[addr & (INTERNAL_FUNCTION_ROM_SIZE - 1)];
}

void internal_function_rom_store(uint16_t addr, uint8_t value)
{
    vicii.last_cpu_val = value;
    /* LTK MMU modification prioritises over internal function rom */
    if (cartridge_get_id(0) == CARTRIDGE_LT_KERNAL) {
        if (c128ltkernal_ram_store(addr, value)) {
            return;
        }
    }
    /* RAMLINK doesn't allow writes; should move on */
    if (internal_function_rom_enabled == INT_FUNCTION_RTC) {
        bq4830y_store(rtc1_context, (uint16_t)(addr & 0x7fff), value);
        ram_store(addr, value);
    } else if (internal_function_rom_enabled == INT_FUNCTION_RAM) {
        int_function_rom[addr & (INTERNAL_FUNCTION_ROM_SIZE - 1)] = value;
        ram_store(addr, value);
    } else {
        ram_store(addr, value);
    }
}

void internal_function_top_shared_store(uint16_t addr, uint8_t value)
{
    vicii.last_cpu_val = value;
    if (internal_function_rom_enabled == INT_FUNCTION_RTC) {
        bq4830y_store(rtc1_context, (uint16_t)(addr & 0x7fff), value);
        top_shared_store(addr, value);
    } else if (internal_function_rom_enabled == INT_FUNCTION_RAM) {
        int_function_rom[addr & (INTERNAL_FUNCTION_ROM_SIZE - 1)] = value;
        top_shared_store(addr, value);
    } else {
        top_shared_store(addr, value);
    }
}