// Emacs style mode select   -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// $Id: txt_main.c 490 2006-05-20 16:34:34Z fraggle $
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005 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.
//
// 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.
//
// $Log$
// Revision 1.5  2006/01/13 23:56:00  fraggle
// Add text-mode I/O functions.
// Use text-mode screen for the waiting screen.
//
// Revision 1.4  2006/01/13 18:23:28  fraggle
// Textscreen getchar() function; remove SDL code from I_Endoom.
//
// Revision 1.3  2005/10/09 20:19:21  fraggle
// Handle blinking text in ENDOOM lumps properly.
//
// Revision 1.2  2005/10/09 16:42:46  fraggle
// Cannot do arithmetic on void pointers in standard C
//
// Revision 1.1  2005/10/02 03:16:03  fraggle
// Text mode emulation code
//
//
//-----------------------------------------------------------------------------
//
// Text mode emulation in SDL
//
//-----------------------------------------------------------------------------

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

#include "doomkeys.h"

#include "txt_main.h"
#include "txt_font.h"

#define CHAR_W 8
#define CHAR_H 16

static SDL_Surface *screen;
static unsigned char *screendata;

static SDL_Color ega_colors[] = 
{
    {0x00, 0x00, 0x00},          // 0: Black
    {0x00, 0x00, 0xa8},          // 1: Blue
    {0x00, 0xa8, 0x00},          // 2: Green
    {0x00, 0xa8, 0xa8},          // 3: Cyan
    {0xa8, 0x00, 0x00},          // 4: Red
    {0xa8, 0x00, 0xa8},          // 5: Magenta
    {0xa8, 0x54, 0x00},          // 6: Brown
    {0xa8, 0xa8, 0xa8},          // 7: Grey
    {0x54, 0x54, 0x54},          // 8: Dark grey
    {0x54, 0x54, 0xfe},          // 9: Bright blue
    {0x54, 0xfe, 0x54},          // 10: Bright green
    {0x54, 0xfe, 0xfe},          // 11: Bright cyan
    {0xfe, 0x54, 0x54},          // 12: Bright red
    {0xfe, 0x54, 0xfe},          // 13: Bright magenta
    {0xfe, 0xfe, 0x54},          // 14: Yellow
    {0xfe, 0xfe, 0xfe},          // 15: Bright white
};

//
// Initialise text mode screen
//
// Returns 1 if successful, 0 if an error occurred
//

int TXT_Init(void)
{
    SDL_InitSubSystem(SDL_INIT_VIDEO);
    
    screen = SDL_SetVideoMode(TXT_SCREEN_W * CHAR_W, TXT_SCREEN_H * CHAR_H, 8, 0);

    if (screen == NULL)
        return 0;

    SDL_SetColors(screen, ega_colors, 0, 16);
    SDL_EnableUNICODE(1);

    screendata = malloc(TXT_SCREEN_W * TXT_SCREEN_H * 2);
    memset(screendata, 0, TXT_SCREEN_W * TXT_SCREEN_H * 2);

    return 1;
}

void TXT_Shutdown(void)
{
    free(screendata);
    SDL_QuitSubSystem(SDL_INIT_VIDEO);
}

unsigned char *TXT_GetScreenData(void)
{
    return screendata;
}

static inline void UpdateCharacter(int x, int y)
{
    unsigned char character;
    unsigned char *p;
    unsigned char *s, *s1;
    int bg, fg;
    int x1, y1;

    p = &screendata[(y * TXT_SCREEN_W + x) * 2];
    character = p[0];

    fg = p[1] & 0xf;
    bg = (p[1] >> 4) & 0xf;

    if (bg & 0x8)
    {
        // blinking

        bg &= ~0x8;

        if (SDL_GetTicks() % 500 < 250)
            fg = bg;
    }

    p = &int10_font_16[character * CHAR_H];

    s = ((unsigned char *) screen->pixels) 
          + (y * CHAR_H * screen->pitch) + (x * CHAR_W);

    for (y1=0; y1<CHAR_H; ++y1)
    {
        s1 = s;

        for (x1=0; x1<CHAR_W; ++x1)
        {
            if (*p & (1 << (7-x1)))
            {
                *s1++ = fg;
            }
            else
            {
                *s1++ = bg;
            }
        }

        ++p;
        s += screen->pitch;
    }
}

void TXT_UpdateScreenArea(int x, int y, int w, int h)
{
    int x1, y1;

    for (y1=y; y1<y+h; ++y1)
    {
        for (x1=x; x1<x+w; ++x1)
        {
            UpdateCharacter(x1, y1);
        }
    }

    SDL_UpdateRect(screen, x * CHAR_W, y * CHAR_H, w * CHAR_W, h * CHAR_H);
}

void TXT_UpdateScreen(void)
{
    TXT_UpdateScreenArea(0, 0, TXT_SCREEN_W, TXT_SCREEN_H);
}

//
// Translates the SDL key
//

static int TranslateKey(SDL_keysym *sym)
{
    switch(sym->sym)
    {
      case SDLK_LEFT:        return KEY_LEFTARROW;
      case SDLK_RIGHT:       return KEY_RIGHTARROW;
      case SDLK_DOWN:        return KEY_DOWNARROW;
      case SDLK_UP:          return KEY_UPARROW;
      case SDLK_ESCAPE:      return KEY_ESCAPE;
      case SDLK_RETURN:      return KEY_ENTER;
      case SDLK_TAB:         return KEY_TAB;
      case SDLK_F1:          return KEY_F1;
      case SDLK_F2:          return KEY_F2;
      case SDLK_F3:          return KEY_F3;
      case SDLK_F4:          return KEY_F4;
      case SDLK_F5:          return KEY_F5;
      case SDLK_F6:          return KEY_F6;
      case SDLK_F7:          return KEY_F7;
      case SDLK_F8:          return KEY_F8;
      case SDLK_F9:          return KEY_F9;
      case SDLK_F10:         return KEY_F10;
      case SDLK_F11:         return KEY_F11;
      case SDLK_F12:         return KEY_F12;
       
      case SDLK_BACKSPACE:   return KEY_BACKSPACE;
      case SDLK_DELETE:      return KEY_DEL;

      case SDLK_PAUSE:       return KEY_PAUSE;

      case SDLK_EQUALS:
      case SDLK_KP_EQUALS:   return KEY_EQUALS;

      case SDLK_MINUS:       return KEY_MINUS;

      case SDLK_LSHIFT:
      case SDLK_RSHIFT:
                             return KEY_RSHIFT;

      case SDLK_LCTRL:
      case SDLK_RCTRL:
                             return KEY_RCTRL;
	
      case SDLK_LALT:
      case SDLK_LMETA:
      case SDLK_RALT:
      case SDLK_RMETA:
                             return KEY_RALT;

      case SDLK_CAPSLOCK:    return KEY_CAPSLOCK;
      case SDLK_SCROLLOCK:   return KEY_SCRLCK;

      case SDLK_KP0:         return KEYP_0;
      case SDLK_KP1:         return KEYP_1;
      case SDLK_KP2:         return KEYP_2;
      case SDLK_KP3:         return KEYP_3;
      case SDLK_KP4:         return KEYP_4;
      case SDLK_KP5:         return KEYP_5;
      case SDLK_KP6:         return KEYP_6;
      case SDLK_KP7:         return KEYP_7;
      case SDLK_KP8:         return KEYP_8;
      case SDLK_KP9:         return KEYP_9;

      case SDLK_HOME:        return KEY_HOME;
      case SDLK_INSERT:      return KEY_INS;
      case SDLK_END:         return KEY_END;
      case SDLK_PAGEUP:      return KEY_PGUP;
      case SDLK_PAGEDOWN:    return KEY_PGDN;
      case SDLK_KP_MULTIPLY: return KEYP_MULTIPLY;
      case SDLK_KP_PLUS:     return KEYP_PLUS;
      case SDLK_KP_MINUS:    return KEYP_MINUS;
      case SDLK_KP_DIVIDE:   return KEYP_DIVIDE;

      default:               return tolower(sym->sym);
    }
}


signed int TXT_GetChar(void)
{
    SDL_Event ev;

    while (SDL_PollEvent(&ev))
    {
        switch (ev.type)
        {
            case SDL_MOUSEBUTTONDOWN:
                if (ev.button.button == SDL_BUTTON_LEFT)
                    return TXT_MOUSE_LEFT;
                else if (ev.button.button == SDL_BUTTON_RIGHT)
                    return TXT_MOUSE_RIGHT;
                else if (ev.button.button == SDL_BUTTON_MIDDLE)
                    return TXT_MOUSE_MIDDLE;
                break;

            case SDL_KEYDOWN:
                return TranslateKey(&ev.key.keysym);

            case SDL_QUIT:
                // Quit = escape
                return 27;

            default:
                break;
        }
    }

    return -1;
}