//
// Copyright(C) 2005-2014 Simon Howard
//
// 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.
//

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

#include "SDL_joystick.h"

#include "doomkeys.h"
#include "joystick.h"
#include "i_joystick.h"
#include "i_system.h"
#include "m_controls.h"
#include "m_misc.h"

#include "txt_joybinput.h"
#include "txt_gui.h"
#include "txt_io.h"
#include "txt_label.h"
#include "txt_sdl.h"
#include "txt_window.h"

#define JOYSTICK_INPUT_WIDTH 10

extern int joystick_physical_buttons[NUM_VIRTUAL_BUTTONS];

// Joystick button variables.
// The ordering of this array is important. We will always try to map
// each variable to the virtual button with the same array index. For
// example: joybfire should always be 0, and then we change
// joystick_physical_buttons[0] to point to the physical joystick
// button that the user wants to use for firing. We do this so that
// the menus work (the game code is hard coded to interpret
// button #0 = select menu item, button #1 = go back to previous menu).
static int *all_joystick_buttons[] =
{
    &joybfire,
    &joybuse,
    &joybstrafe,
    &joybspeed,
    &joybstrafeleft,
    &joybstraferight,
    &joybprevweapon,
    &joybnextweapon,
    &joybjump,
    &joybmenu,
};

static int PhysicalForVirtualButton(int vbutton)
{
    if (vbutton < NUM_VIRTUAL_BUTTONS)
    {
        return joystick_physical_buttons[vbutton];
    }
    else
    {
        return vbutton;
    }
}

// Get the virtual button number for the given variable, ie. the
// variable's index in all_joystick_buttons[].
static int VirtualButtonForVariable(int *variable)
{
    int i;

    for (i = 0; i < arrlen(all_joystick_buttons); ++i)
    {
        if (variable == all_joystick_buttons[i])
        {
            return i;
        }
    }

    I_Error("Couldn't find virtual button");
    return -1;
}

// Rearrange joystick button configuration to be in "canonical" form:
// each joyb* variable should have a value equal to its index in
// all_joystick_buttons[] above.
static void CanonicalizeButtons(void)
{
    int new_mapping[NUM_VIRTUAL_BUTTONS];
    int vbutton;
    int i;

    for (i = 0; i < arrlen(all_joystick_buttons); ++i)
    {
        vbutton = *all_joystick_buttons[i];

        // Don't remap the speed key if it's bound to "always run".
        // Also preserve "unbound" variables.
        if ((all_joystick_buttons[i] == &joybspeed && vbutton >= 20)
         || vbutton < 0)
        {
            new_mapping[i] = i;
        }
        else
        {
            new_mapping[i] = PhysicalForVirtualButton(vbutton);
            *all_joystick_buttons[i] = i;
        }
    }

    for (i = 0; i < NUM_VIRTUAL_BUTTONS; ++i)
    {
        joystick_physical_buttons[i] = new_mapping[i];
    }
}

// Check all existing buttons and clear any using the specified physical
// button.
static void ClearVariablesUsingButton(int physbutton)
{
    int vbutton;
    int i;

    for (i = 0; i < arrlen(all_joystick_buttons); ++i)
    {
        vbutton = *all_joystick_buttons[i];

        if (vbutton >= 0 && physbutton == PhysicalForVirtualButton(vbutton))
        {
            *all_joystick_buttons[i] = -1;
        }
    }
}

// Called in response to SDL events when the prompt window is open:

static int EventCallback(SDL_Event *event, TXT_UNCAST_ARG(joystick_input))
{
    TXT_CAST_ARG(txt_joystick_input_t, joystick_input);

    // Got the joystick button press?

    if (event->type == SDL_JOYBUTTONDOWN)
    {
        int vbutton, physbutton;

        // Before changing anything, remap button configuration into
        // canonical form, to avoid conflicts.
        CanonicalizeButtons();

        vbutton = VirtualButtonForVariable(joystick_input->variable);
        physbutton = event->jbutton.button;

        if (joystick_input->check_conflicts)
        {
            ClearVariablesUsingButton(physbutton);
        }

        // Set mapping.
        *joystick_input->variable = vbutton;
        joystick_physical_buttons[vbutton] = physbutton;

        TXT_CloseWindow(joystick_input->prompt_window);
        return 1;
    }

    return 0;
}

// When the prompt window is closed, disable the event callback function;
// we are no longer interested in receiving notification of events.

static void PromptWindowClosed(TXT_UNCAST_ARG(widget), TXT_UNCAST_ARG(joystick))
{
    TXT_CAST_ARG(SDL_Joystick, joystick);

    SDL_JoystickClose(joystick);
    TXT_SDL_SetEventCallback(NULL, NULL);
    SDL_JoystickEventState(SDL_DISABLE);
    SDL_QuitSubSystem(SDL_INIT_JOYSTICK);
}

static void OpenErrorWindow(void)
{
    TXT_MessageBox(NULL, "Please configure a joystick first!");
}

static void OpenPromptWindow(txt_joystick_input_t *joystick_input)
{
    txt_window_t *window;
    SDL_Joystick *joystick;

    // Silently update when the shift button is held down.

    joystick_input->check_conflicts = !TXT_GetModifierState(TXT_MOD_SHIFT);

    if (SDL_Init(SDL_INIT_JOYSTICK) < 0)
    {
        return;
    }

    // Check the current joystick is valid

    joystick = SDL_JoystickOpen(joystick_index);

    if (joystick == NULL)
    {
        OpenErrorWindow();
        return;
    }

    // Open the prompt window

    window = TXT_MessageBox(NULL, "Press the new joystick button...");

    TXT_SDL_SetEventCallback(EventCallback, joystick_input);
    TXT_SignalConnect(window, "closed", PromptWindowClosed, joystick);
    joystick_input->prompt_window = window;

    SDL_JoystickEventState(SDL_ENABLE);
}

static void TXT_JoystickInputSizeCalc(TXT_UNCAST_ARG(joystick_input))
{
    TXT_CAST_ARG(txt_joystick_input_t, joystick_input);

    // All joystickinputs are the same size.

    joystick_input->widget.w = JOYSTICK_INPUT_WIDTH;
    joystick_input->widget.h = 1;
}

static void GetJoystickButtonDescription(int vbutton, char *buf,
                                         size_t buf_len)
{
    M_snprintf(buf, buf_len, "BUTTON #%i",
               PhysicalForVirtualButton(vbutton) + 1);
}

static void TXT_JoystickInputDrawer(TXT_UNCAST_ARG(joystick_input))
{
    TXT_CAST_ARG(txt_joystick_input_t, joystick_input);
    char buf[20];
    int i;

    if (*joystick_input->variable < 0)
    {
        M_StringCopy(buf, "(none)", sizeof(buf));
    }
    else
    {
        GetJoystickButtonDescription(*joystick_input->variable,
                                     buf, sizeof(buf));
    }

    TXT_SetWidgetBG(joystick_input);
    TXT_FGColor(TXT_COLOR_BRIGHT_WHITE);

    TXT_DrawString(buf);

    for (i=strlen(buf); i<JOYSTICK_INPUT_WIDTH; ++i)
    {
        TXT_DrawString(" ");
    }
}

static void TXT_JoystickInputDestructor(TXT_UNCAST_ARG(joystick_input))
{
}

static int TXT_JoystickInputKeyPress(TXT_UNCAST_ARG(joystick_input), int key)
{
    TXT_CAST_ARG(txt_joystick_input_t, joystick_input);

    if (key == KEY_ENTER)
    {
        // Open a window to prompt for the new joystick press

        OpenPromptWindow(joystick_input);

        return 1;
    }

    if (key == KEY_BACKSPACE || key == KEY_DEL)
    {
        *joystick_input->variable = -1;
    }

    return 0;
}

static void TXT_JoystickInputMousePress(TXT_UNCAST_ARG(widget), int x, int y, int b)
{
    TXT_CAST_ARG(txt_joystick_input_t, widget);

    // Clicking is like pressing enter

    if (b == TXT_MOUSE_LEFT)
    {
        TXT_JoystickInputKeyPress(widget, KEY_ENTER);
    }
}

txt_widget_class_t txt_joystick_input_class =
{
    TXT_AlwaysSelectable,
    TXT_JoystickInputSizeCalc,
    TXT_JoystickInputDrawer,
    TXT_JoystickInputKeyPress,
    TXT_JoystickInputDestructor,
    TXT_JoystickInputMousePress,
    NULL,
};

txt_joystick_input_t *TXT_NewJoystickInput(int *variable)
{
    txt_joystick_input_t *joystick_input;

    joystick_input = malloc(sizeof(txt_joystick_input_t));

    TXT_InitWidget(joystick_input, &txt_joystick_input_class);
    joystick_input->variable = variable;

    return joystick_input;
}