mupen64plus-core/src/backends/plugins_compat/input_plugin_compat.c

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *   Mupen64plus - input_plugin_compat.c                                   *
 *   Mupen64Plus homepage: https://mupen64plus.org/                        *
 *   Copyright (C) 2014 Bobby Smiles                                       *
 *                                                                         *
 *   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.          *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include "plugins_compat.h"

#include "api/m64p_plugin.h"
#include "backends/api/controller_input_backend.h"
#include "backends/api/rumble_backend.h"
#include "plugin/plugin.h"

#include "main/main.h"
#include "main/netplay.h"

#include <stdint.h>
#include <string.h>
#include <api/m64p_plugin.h>
#include <api/callbacks.h>

/* XXX: this is an abuse of the Zilmar Spec normally this value is reserved */
enum {
    PAK_SWITCH_BUTTON = 0x4000,
    GB_CART_SWITCH_BUTTON = 0x8000
};

/* Pak switching delay
 * If you put too low value,
 * some games (for instance Perfect Dark) won't be able to detect the pak change
 * causing incorrect pak accesses */
enum { PAK_SWITCH_DELAY = 20 };
enum { GB_CART_SWITCH_DELAY = 20 };

static int is_button_released(uint32_t input, uint32_t last_input, uint32_t mask)
{
    return ((input & mask) == 0)
        && ((last_input & mask) != 0);
}

static m64p_error input_plugin_get_input(void* opaque, uint32_t* input_)
{
    struct controller_input_compat* cin_compat = (struct controller_input_compat*)opaque;
    BUTTONS keys = { 0 };

    int pak_change_requested = 0;

    /* first poll controller */
    if (!netplay_is_init())
    {
        if (input.getKeys)
            input.getKeys(cin_compat->control_id, &keys);
    }
    else
    {
        int netplay_controller = netplay_get_controller(cin_compat->control_id);
        if (netplay_controller >= 0)
        {
            //Here we "trick" the input plugin
            //by passing it the controller number that is controlling the player during netplay
            uint8_t plugin = Controls[netplay_controller].Plugin;
            uint8_t present = Controls[netplay_controller].Present;
            if (input.getKeys)
                input.getKeys(netplay_controller, &keys);

            netplay_set_plugin(cin_compat->control_id, Controls[netplay_controller].Plugin);
            Controls[netplay_controller].Plugin = plugin;
            Controls[netplay_controller].Present = present;
            cin_compat->last_input = keys.Value; //disable pak switching for netplay
        }
    }

    /* return an error if controller is not plugged */
    if (!Controls[cin_compat->control_id].Present) {
        return M64ERR_SYSTEM_FAIL;
    }


    /* has Controls[i].Plugin changed since last call */
    if (cin_compat->last_pak_type != Controls[cin_compat->control_id].Plugin) {
        pak_change_requested = 1;
        cin_compat->main_switch_pak = main_switch_plugin_pak;
    }

    /* or has the PAK_SWITCH_BUTTON been released */
    if (is_button_released(keys.Value, cin_compat->last_input, PAK_SWITCH_BUTTON)) {
        pak_change_requested = 1;
        cin_compat->main_switch_pak = main_switch_next_pak;
    }

    /* if so, immediately disconnect current pak (if any)
     * and start the pak switch delay */
    if (pak_change_requested) {
        change_pak(cin_compat->cont, NULL, NULL);
        cin_compat->pak_switch_delay = PAK_SWITCH_DELAY;
    }

    /* switch to next/selected pak after switch delay has expired */
    if (cin_compat->pak_switch_delay > 0 && --cin_compat->pak_switch_delay == 0) {
        cin_compat->main_switch_pak(cin_compat->control_id);
        cin_compat->main_switch_pak = NULL;
    }

    if (cin_compat->gb_cart_switch_enabled) {
        /* disconnect current GB cart (if any) immediately after "GB cart switch" button is released */
        if (is_button_released(keys.Value, cin_compat->last_input, GB_CART_SWITCH_BUTTON)) {
            change_gb_cart(cin_compat->tpk, NULL);
            cin_compat->gb_switch_delay = GB_CART_SWITCH_DELAY;
        }

        /* switch to new GB cart after switch delay has expired */
        if (cin_compat->gb_switch_delay > 0 && --cin_compat->gb_switch_delay == 0) {
            main_change_gb_cart(cin_compat->control_id);
        }
    }

    cin_compat->last_pak_type = Controls[cin_compat->control_id].Plugin;
    cin_compat->last_input = keys.Value;

    *input_ = keys.Value;
    return M64ERR_SUCCESS;
}

const struct controller_input_backend_interface
    g_icontroller_input_backend_plugin_compat =
{
    input_plugin_get_input
};


static void input_plugin_rumble_exec(void* opaque, enum rumble_action action)
{
    int control_id = *(int*)opaque;

    if (input.controllerCommand == NULL) {
        return;
    }

    //This is for netplay, -1 means there is no local controller controlling this player
    if (control_id == -1) {
        return;
    }

    static const uint8_t rumble_cmd_header[] =
    {
        0x23, 0x01, /* T=0x23, R=0x01 */
        JCMD_PAK_WRITE,
        0xc0, 0x1b, /* address=0xc000 | crc=0x1b */
    };

    uint8_t cmd[0x26];

    uint8_t rumble_data = (action == RUMBLE_START)
        ? 0x01
        : 0x00;

    /* build rumble command */
    memcpy(cmd, rumble_cmd_header, 5);
    memset(cmd + 5, rumble_data, 0x20);
    cmd[0x25] = 0; /* dummy data CRC */

    input.controllerCommand(control_id, cmd);
}

const struct rumble_backend_interface
    g_irumble_backend_plugin_compat =
{
    input_plugin_rumble_exec
};


static void input_plugin_read_controller(void* opaque,
    const uint8_t* tx, const uint8_t* tx_buf,
    uint8_t* rx, uint8_t* rx_buf)
{
    int control_id = *(int*)opaque;

    if (input.readController == NULL) {
        return;
    }

    //This is for netplay, -1 means there is no local controller controlling this player
    if (control_id == -1) {
        return;
    }

    /* UGLY: use negative offsets to get access to non-const tx pointer */
    input.readController(control_id, rx - 1);
}

void input_plugin_controller_command(void* opaque,
    uint8_t* tx, const uint8_t* tx_buf,
    const uint8_t* rx, const uint8_t* rx_buf)
{
    int control_id = *(int*)opaque;

    if (input.controllerCommand == NULL) {
        return;
    }

    //This is for netplay, -1 means there is no local controller controlling this player
    if (control_id == -1) {
        return;
    }

    input.controllerCommand(control_id, tx);
}

const struct joybus_device_interface
    g_ijoybus_device_plugin_compat =
{
    NULL,
    input_plugin_read_controller,
    input_plugin_controller_command,
};