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

#include "doomkeys.h"
#include "m_misc.h"

#include "txt_keyinput.h"
#include "txt_gui.h"
#include "txt_io.h"
#include "txt_label.h"
#include "txt_window.h"

#define KEY_INPUT_WIDTH 8

static int KeyPressCallback(txt_window_t *window, int key, 
                            TXT_UNCAST_ARG(key_input))
{
    TXT_CAST_ARG(txt_key_input_t, key_input);

    if (key != KEY_ESCAPE)
    {
        // Got the key press.  Save to the variable and close the window.

        *key_input->variable = key;

        if (key_input->check_conflicts)
        {
            TXT_EmitSignal(key_input, "set");
        }

        TXT_CloseWindow(window);

        // Re-enable key mappings now that we have the key

        TXT_EnableKeyMapping(1);

        return 1;
    }
    else
    {
        return 0;
    }
}

static void ReleaseGrab(TXT_UNCAST_ARG(window), TXT_UNCAST_ARG(unused))
{
    SDL_WM_GrabInput(SDL_GRAB_OFF);
}

static void OpenPromptWindow(txt_key_input_t *key_input)
{
    txt_window_t *window;

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

    key_input->check_conflicts = !TXT_GetModifierState(TXT_MOD_SHIFT);

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

    TXT_SetKeyListener(window, KeyPressCallback, key_input);

    // Disable key mappings while we prompt for the key press

    TXT_EnableKeyMapping(0);

    // Grab input while reading the key.  On Windows Mobile
    // handheld devices, the hardware keypresses are only
    // detected when input is grabbed.

    SDL_WM_GrabInput(SDL_GRAB_ON);
    TXT_SignalConnect(window, "closed", ReleaseGrab, NULL);
}

static void TXT_KeyInputSizeCalc(TXT_UNCAST_ARG(key_input))
{
    TXT_CAST_ARG(txt_key_input_t, key_input);

    // All keyinputs are the same size.

    key_input->widget.w = KEY_INPUT_WIDTH;
    key_input->widget.h = 1;
}


static void TXT_KeyInputDrawer(TXT_UNCAST_ARG(key_input))
{
    TXT_CAST_ARG(txt_key_input_t, key_input);
    char buf[20];
    int i;

    if (*key_input->variable == 0)
    {
        M_StringCopy(buf, "(none)", sizeof(buf));
    }
    else
    {
        TXT_GetKeyDescription(*key_input->variable, buf, sizeof(buf));
    }

    TXT_SetWidgetBG(key_input);
    TXT_FGColor(TXT_COLOR_BRIGHT_WHITE);
    
    TXT_DrawString(buf);
    
    for (i=strlen(buf); i<KEY_INPUT_WIDTH; ++i)
    {
        TXT_DrawString(" ");
    }
}

static void TXT_KeyInputDestructor(TXT_UNCAST_ARG(key_input))
{
}

static int TXT_KeyInputKeyPress(TXT_UNCAST_ARG(key_input), int key)
{
    TXT_CAST_ARG(txt_key_input_t, key_input);

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

        OpenPromptWindow(key_input);

        return 1;
    }

    if (key == KEY_BACKSPACE || key == KEY_DEL)
    {
        *key_input->variable = 0;
    }

    return 0;
}

static void TXT_KeyInputMousePress(TXT_UNCAST_ARG(widget), int x, int y, int b)
{
    TXT_CAST_ARG(txt_key_input_t, widget);
            
    // Clicking is like pressing enter

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

txt_widget_class_t txt_key_input_class =
{
    TXT_AlwaysSelectable,
    TXT_KeyInputSizeCalc,
    TXT_KeyInputDrawer,
    TXT_KeyInputKeyPress,
    TXT_KeyInputDestructor,
    TXT_KeyInputMousePress,
    NULL,
};

txt_key_input_t *TXT_NewKeyInput(int *variable)
{
    txt_key_input_t *key_input;

    key_input = malloc(sizeof(txt_key_input_t));

    TXT_InitWidget(key_input, &txt_key_input_class);
    key_input->variable = variable;

    return key_input;
}