/**
 * Copyright (c) 2025 Dominic Masters
 * 
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#include "texture.h"
#include "assert/assert.h"
#include "util/memory.h"
#include "util/math.h"

const texture_t *TEXTURE_BOUND = NULL;

void textureInit(
  texture_t *texture,
  const int32_t width,
  const int32_t height,
  const textureformat_t format,
  const void *data
) {
  assertNotNull(texture, "Texture cannot be NULL");
  assertTrue(width > 0 && height > 0, "width/height must be greater than 0");

  memoryZero(texture, sizeof(texture_t));
  texture->width = width;
  texture->height = height;

  #if PSP
    assertTrue(
      width == mathNextPowTwo(width),
      "Width must be powers of 2 for PSP"
    );
    assertTrue(
      height == mathNextPowTwo(height),
      "Height must be powers of 2 for PSP"
    );
  #endif

  #if DUSK_DISPLAY_SDL2
    glGenTextures(1, &texture->id);
    glBindTexture(GL_TEXTURE_2D, texture->id);
    glTexImage2D(
      GL_TEXTURE_2D, 0, format, width, height, 0,
      format, GL_UNSIGNED_BYTE, data
    );

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
    
    glBindTexture(GL_TEXTURE_2D, 0);
  #endif
}

void textureBind(const texture_t *texture) {
  if(TEXTURE_BOUND == texture) return;

  if(texture == NULL) {
    #if DUSK_DISPLAY_SDL2
      glDisable(GL_TEXTURE_2D);
    #endif
    TEXTURE_BOUND = NULL;
    return;
  }

  assertTrue(
    texture->id != 0,
    "Texture ID must not be 0"
  );
  assertTrue(
    texture->width > 0 && texture->height > 0,
    "Texture width and height must be greater than 0"
  );

  #if DUSK_DISPLAY_SDL2
    glEnable(GL_TEXTURE_2D);
    glBindTexture(GL_TEXTURE_2D, texture->id);
  #endif
  TEXTURE_BOUND = texture;
}

void textureDispose(texture_t *texture) {
  assertNotNull(texture, "Texture cannot be NULL");
  assertTrue(texture->id != 0, "Texture ID must not be 0");

  #if DUSK_DISPLAY_SDL2
    glDeleteTextures(1, &texture->id);
  #endif
}