/*
 * Processing of images uploaded by the user 
 * (resizing, cropping, saving)
 */

#include "img_handler.hpp"
#include "puzzle.hpp"

#define STB_IMAGE_IMPLEMENTATION
#define STB_IMAGE_WRITE_IMPLEMENTATION
#define STB_IMAGE_RESIZE_IMPLEMENTATION
#include "lib/stb_image.h"
#include "lib/stb_image_resize2.h"
#include "lib/stb_image_write.h"

#include <stdlib.h>
#include <filesystem>
#include <stdio.h>
#include <iostream>
#include <string>

ImageHandler::ImageHandler(const char *p) : source_path(p) {
    img_data = nullptr;
    resized_data = nullptr;
    /*
     * creating resources directory (if it didn't exist)
     */
    std::filesystem::path res_path = std::string("resources");
    if(!std::filesystem::exists(res_path))
        std::filesystem::create_directory(res_path);

#if defined(_WIN32)
    auto it = source_path.find_last_of('\\');
#else
    auto it = source_path.find_last_of('/');
#endif
    std::string file_name = source_path.substr(it + 1);
    std::string fn_withot_ext =
        file_name.substr(0, file_name.find_first_of('.'));
#if defined(_WIN32)
    destination_directory = "resources\\" + fn_withot_ext + "\\";
#else
    destination_directory = "resources/" + fn_withot_ext + '/';
#endif
    std::filesystem::create_directory(destination_directory);
}

void ImageHandler::load_img()
{
    img_data = stbi_load(source_path.c_str(), &in_width, &in_height,
                         &channel, 0);
}

void ImageHandler::resize_img()
{
    resized_data =
        reinterpret_cast<unsigned char*>(malloc(in_width * in_height *
                                                                    channel));
    stbir_resize_uint8_linear(img_data, in_width, in_height, 0, resized_data,
                              width, height, 0, (stbir_pixel_layout) channel);
}

void ImageHandler::save_img()
{
    int x, y, i, j, k = 0;
    for(i = 0; i < puzzles_per_side; ++i)
        for(j = 0; j < puzzles_per_side; ++j, ++k) {
            x = i * puzzle_size;
            y = j * puzzle_size;
            std::string tmp_path =
                destination_directory +
                std::to_string(k / puzzles_per_side) +
                std::to_string(k % puzzles_per_side) + ".png";
            stbi_write_png(tmp_path.c_str(), puzzle_size, puzzle_size, channel,
                           resized_data + channel * (x + y * width),
                           width * channel);
        }
    stbi_image_free(resized_data);
    stbi_image_free(img_data);
}