// Copyright (c) 2023 Dominic Masters
// 
// This software is released under the MIT License.
// https://opensource.org/licenses/MIT

#include "TextureGen.hpp"

using namespace Dawn;

std::vector<std::string> TextureGen::getRequiredFlags() {
  return std::vector<std::string>{ "input", "output" };
}

int32_t TextureGen::start() {
  // Finished with XML data, now we can write data out.
  File fileOut(flags["output"] + ".texture");
  if(fileOut.exists()) return 0;

  // Load input file
  File in(flags["input"]);
  if(!in.open(FILE_MODE_READ)) return 1;

  int w, h, channels;
  auto imageRaw = stbi_load_from_file(in.file, &w, &h, &channels, STBI_rgb_alpha);
  if(imageRaw == NULL) {
    std::cout << "Failed to load input texture!" << std::endl;
    return 1;
  }
  in.close();

  // Convert to floating points
  size_t len = STBI_rgb_alpha * w * h;
  float_t *dataImage = (float_t*)malloc(sizeof(float) * len);
  for(size_t i = 0; i < len; i++) {
    auto dataIn = imageRaw[i];
    dataImage[i] = ((float_t)dataIn) / 255.0f;
  }
  stbi_image_free(imageRaw);

  // Open and create output
  File out(flags["output"] + ".texture");
  if(!out.mkdirp()) {
    std::cout << "Failed to make output dir " << out.filename << std::endl;
    return 1;
  }
  if(!out.open(FILE_MODE_WRITE)) {
    std::cout << "Failed to open texture file for writing " << out.filename << std::endl;
    return 1;
  }

  // Write info
  char headerBuffer[64];
  size_t headerBufferLength = sprintf((char *)headerBuffer, "%i|%i|", w, h);
  if(!out.writeRaw(headerBuffer, headerBufferLength)) {
    std::cout << "Failed to write texture header for " << out.filename << std::endl;
    return 1;
  }

  // Write texture
  if(!out.writeRaw((char *)dataImage, sizeof(float_t) * len)) {
    std::cout << "Failed to write texture data for " << out.filename << std::endl;
    return 1;
  }
  free(dataImage);

  return 0;
}