image.cpp

#include "image.h"

#include <algorithm>
#include <cstring>
#include <span>
#include <stdexcept>
#include <string>

#define STB_IMAGE_IMPLEMENTATION
#include "stb_image.h"
#define STB_IMAGE_WRITE_IMPLEMENTATION
#include "stb_image_write.h"

Image::Image(std::span<const uint8_t> data) {
  data_ = (uint32_t *)stbi_load_from_memory(data.data(), data.size(), &width,
                                            &height, nullptr, 4);
  if (data_ == nullptr) {
    throw std::runtime_error("failed to load image");
  }
}

Image::Image(const std::string &path) {
  data_ = (uint32_t *)stbi_load(path.c_str(), &width, &height, nullptr, 4);
  if (data_ == nullptr) {
    throw std::runtime_error("failed to load image");
  }
}

Image::Image(int width, int height) : width(width), height(height) {
  data_ = (uint32_t *)malloc(width * height * 4);
  std::memset(data_, 0, width * height * 4);
}

Image::Image(Image &&other) noexcept {
  data_ = other.data_;
  width = other.width;
  height = other.height;

  other.data_ = nullptr;
  other.width = 0;
  other.height = 0;
}

Image::Image(const char *data, size_t size) {
  data_ = (uint32_t *)stbi_load_from_memory((stbi_uc *)data, size, &width,
                                            &height, nullptr, 4);
  if (data_ == nullptr) {
    throw std::runtime_error("failed to load image");
  }
}

Image::~Image() { free(data_); }

void Image::save_png(const std::string &path) {
  stbi_write_png(path.c_str(), width, height, 4, data_, width * 4);
}

const void *Image::get_png(int *len) {
  return stbi_write_png_to_mem((const unsigned char *)data_, width * 4, width,
                               height, 4, len);
}

void Image::save_png_from_data(const std::string &path, const void *data, int w,
                               int h) {
  stbi_write_png(path.c_str(), w, h, 4, data, w * 4);
}