/*  RetroArch - A frontend for libretro.
 *  Copyright (C) 2010-2014 - Hans-Kristian Arntzen
 *  Copyright (C) 2011-2017 - Daniel De Matteis
 *  Copyright (C) 2016-2019 - Brad Parker
 *
 *  RetroArch 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 Found-
 *  ation, either version 3 of the License, or (at your option) any later version.
 *
 *  RetroArch 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 RetroArch.
 *  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdlib.h>
#include <string/stdstring.h>
#include <encodings/utf.h>
#include <lists/string_list.h>

#include <windows.h>
#include <wingdi.h>

#ifdef HAVE_CONFIG_H
#include "../../config.h"
#endif

#include "../../retroarch.h"
#include "../common/gdi_common.h"
#include "../common/win32_common.h"

#include "../font_driver.h"
#include "../../configuration.h"

typedef struct
{
   const font_renderer_driver_t *font_driver;
   void *font_data;
   gdi_t *gdi;
} gdi_raster_t;

static void *gdi_font_init(void *data,
      const char *font_path, float font_size,
      bool is_threaded)
{
   gdi_raster_t *font  = (gdi_raster_t*)calloc(1, sizeof(*font));

   if (!font)
      return NULL;

   font->gdi = (gdi_t*)data;

   if (!font_renderer_create_default(
            &font->font_driver,
            &font->font_data, font_path, font_size))
      return NULL;

   return font;
}

static void gdi_font_free(void *data, bool is_threaded)
{
  gdi_raster_t *font = (gdi_raster_t*)data;

  if (!font)
     return;

  if (font->font_driver && font->font_data && font->font_driver->free)
     font->font_driver->free(font->font_data);

  free(font);
}

static void gdi_font_render_msg(
      void *userdata,
      void *data,
      const char *msg,
      const struct font_params *params)
{
   size_t i;
   char* msg_local;
   size_t msg_len;
   float x, y, scale, drop_mod, drop_alpha;
   int drop_x, drop_y;
   unsigned new_x, new_y, new_drop_x, new_drop_y;
   unsigned align;
   unsigned red, green, blue;
   gdi_t *gdi                       = (gdi_t*)userdata;
   gdi_raster_t *font               = (gdi_raster_t*)data;
   unsigned width                   = gdi->video_width;
   unsigned height                  = gdi->video_height;
   SIZE text_size                   = {0};
   struct string_list msg_list      = {0};

   if (!font || string_is_empty(msg) || !font->gdi)
      return;

   if (params)
   {
      x                       = params->x;
      y                       = params->y;
      drop_x                  = params->drop_x;
      drop_y                  = params->drop_y;
      drop_mod                = params->drop_mod;
      drop_alpha              = params->drop_alpha;
      scale                   = params->scale;
      align                   = params->text_align;

      red                     = FONT_COLOR_GET_RED(params->color);
      green                   = FONT_COLOR_GET_GREEN(params->color);
      blue                    = FONT_COLOR_GET_BLUE(params->color);
   }
   else
   {
      settings_t *settings    = config_get_ptr();
      float video_msg_pos_x   = settings->floats.video_msg_pos_x;
      float video_msg_pos_y   = settings->floats.video_msg_pos_y;
      float video_msg_color_r = settings->floats.video_msg_color_r;
      float video_msg_color_g = settings->floats.video_msg_color_g;
      float video_msg_color_b = settings->floats.video_msg_color_b;
      x                       = video_msg_pos_x;
      y                       = video_msg_pos_y;
      drop_x                  = -2;
      drop_y                  = -2;
      drop_mod                = 0.3f;
      drop_alpha              = 1.0f;
      scale                   = 1.0f;
      align                   = TEXT_ALIGN_LEFT;
      red                     = video_msg_color_r * 255.0f;
      green                   = video_msg_color_g * 255.0f;
      blue                    = video_msg_color_b * 255.0f;
   }

   msg_local                  = utf8_to_local_string_alloc(msg);
   msg_len                    = strlen(msg_local);

   GetTextExtentPoint32(font->gdi->memDC, msg_local, (int)msg_len, &text_size);

   switch (align)
   {
      case TEXT_ALIGN_LEFT:
         new_x        = x * width * scale;
         new_drop_x   = drop_x * width * scale;
         break;
      case TEXT_ALIGN_RIGHT:
         new_x        = (x * width * scale) - text_size.cx;
         new_drop_x   = (drop_x * width * scale) - text_size.cx;
         break;
      case TEXT_ALIGN_CENTER:
         new_x        = (x * width * scale) - (text_size.cx / 2);
         new_drop_x   = (drop_x * width * scale) - (text_size.cx / 2);
         break;
      default:
         new_x        = 0;
         new_drop_x   = 0;
         break;
   }

   new_y              = height - (y * height * scale)      - text_size.cy;
   new_drop_y         = height - (drop_y * height * scale) - text_size.cy;

   font->gdi->bmp_old = (HBITMAP)SelectObject(font->gdi->memDC, font->gdi->bmp);

   SetBkMode(font->gdi->memDC, TRANSPARENT);

   string_list_initialize(&msg_list);
   string_split_noalloc(&msg_list, msg_local, "\n");

   if (drop_x || drop_y)
   {
      float    dark_alpha = drop_alpha;
      unsigned drop_red   = red * drop_mod * dark_alpha;
      unsigned drop_green = green * drop_mod * dark_alpha;
      unsigned drop_blue  = blue * drop_mod * dark_alpha;

      SetTextColor(font->gdi->memDC, RGB(drop_red, drop_green, drop_blue));

      for (i = 0; i < msg_list.size; i++)
         TextOut(font->gdi->memDC, new_drop_x,
               new_drop_y + (text_size.cy * i),
               msg_list.elems[i].data,
               strlen(msg_list.elems[i].data));
   }

   SetTextColor(font->gdi->memDC, RGB(red, green, blue));

   for (i = 0; i < msg_list.size; i++)
      TextOut(font->gdi->memDC, new_x, new_y + (text_size.cy * i),
            msg_list.elems[i].data,
            strlen(msg_list.elems[i].data));

   string_list_deinitialize(&msg_list);
   free(msg_local);

   SelectObject(font->gdi->memDC, font->gdi->bmp_old);
}

font_renderer_t gdi_font = {
   gdi_font_init,
   gdi_font_free,
   gdi_font_render_msg,
   "gdi_font",
   NULL,                      /* get_glyph */
   NULL,                      /* bind_block */
   NULL,                      /* flush */
   NULL,                      /* get_message_width */
   NULL                       /* get_line_metrics */
};