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

#include "assettexture.h"
#include "asset/assettype.h"
#include "assert/assert.h"
#include "display/texture/texture.h"
#include "util/endian.h"

errorret_t assetTextureLoad(assetentire_t entire) {
  assertNotNull(entire.data, "Data pointer cannot be NULL.");
  assertNotNull(entire.output, "Output pointer cannot be NULL.");

  assettexture_t *assetData = (assettexture_t *)entire.data;
  texture_t *texture = (texture_t *)entire.output;

  // Read header and version (first 4 bytes)
  if(
    assetData->header[0] != 'D' || 
    assetData->header[1] != 'T' ||
    assetData->header[2] != 'X'
  ) {
    errorThrow("Invalid texture header");
  }
  
  // Version (can only be 1 atm)
  if(assetData->version != 0x01) {
    errorThrow("Unsupported texture version");
  }

  // Fix endian
  assetData->width = endianLittleToHost32(assetData->width);
  assetData->height = endianLittleToHost32(assetData->height);

  // Check dimensions.
  if(
    assetData->width == 0 || assetData->width > ASSET_TEXTURE_WIDTH_MAX ||
    assetData->height == 0 || assetData->height > ASSET_TEXTURE_HEIGHT_MAX
  ) {
    errorThrow("Invalid texture dimensions");
  }

  // Validate format
  textureformat_t format;
  texturedata_t data;

  switch(assetData->type) {
    case 0x00: // RGBA8888
      format = TEXTURE_FORMAT_RGBA;
      data.rgbaColors = (color_t *)assetData->data;
      break;

    // case 0x01:
    //   format = TEXTURE_FORMAT_RGB;
    //   break;
    
    // case 0x02:
    //   format = TEXTURE_FORMAT_RGB565;
    //   break;

    // case 0x03:
    //   format = TEXTURE_FORMAT_RGB5A3;
    //   break;

    default:
      errorThrow("Unsupported texture format");
  }

  errorChain(textureInit(
    texture, assetData->width, assetData->height, format, data
  ));

  errorOk();
}