/**
 * Copyright (c) 2026 Dominic Masters
 * 
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#include "asset/asset.h"
#include "assert/assert.h"
#include "display/texture/tileset.h"
#include "util/memory.h"
#include "util/endian.h"

errorret_t assetTilesetLoad(assetentire_t entire) {
  assertNotNull(entire.data, "Asset data cannot be null");
  assertNotNull(entire.output, "Asset output cannot be null");

  assettileset_t *tilesetData = (assettileset_t *)entire.data;
  tileset_t *tileset = (tileset_t *)entire.output;

  if(
    tilesetData->header[0] != 'D' || 
    tilesetData->header[1] != 'T' ||
    tilesetData->header[2] != 'F'
  ) {
    errorThrow("Invalid tileset header");
  }

  if(tilesetData->version != 0x00) {
    errorThrow("Unsupported tileset version");
  }

  // Fix endianness
  tilesetData->tileWidth = endianLittleToHost16(tilesetData->tileWidth);
  tilesetData->tileHeight = endianLittleToHost16(tilesetData->tileHeight);
  tilesetData->columnCount = endianLittleToHost16(tilesetData->columnCount);
  tilesetData->rowCount = endianLittleToHost16(tilesetData->rowCount);
  tilesetData->right = endianLittleToHost16(tilesetData->right);
  tilesetData->bottom = endianLittleToHost16(tilesetData->bottom);

  if(tilesetData->tileWidth == 0) {
    errorThrow("Tile width cannot be 0");
  }
  if(tilesetData->tileHeight == 0) {
    errorThrow("Tile height cannot be 0");
  }
  if(tilesetData->columnCount == 0) {
    errorThrow("Column count cannot be 0");
  }
  if(tilesetData->rowCount == 0) {
    errorThrow("Row count cannot be 0");
  }

  tilesetData->u0 = endianLittleToHostFloat(tilesetData->u0);
  tilesetData->v0 = endianLittleToHostFloat(tilesetData->v0);

  if(tilesetData->v0 < 0.0f || tilesetData->v0 > 1.0f) {
    errorThrow("Invalid v0 value in tileset");
  }

  // Setup tileset
  tileset->tileWidth = tilesetData->tileWidth;
  tileset->tileHeight = tilesetData->tileHeight;
  tileset->tileCount = tilesetData->columnCount * tilesetData->rowCount;
  tileset->columns = tilesetData->columnCount;
  tileset->rows = tilesetData->rowCount;
  tileset->uv[0] = tilesetData->u0;
  tileset->uv[1] = tilesetData->v0;
  errorOk();
}