#include "GameSingleton.hpp"

#include <godot_cpp/classes/file_access.hpp>
#include <godot_cpp/classes/json.hpp>
#include <godot_cpp/variant/utility_functions.hpp>

#include "openvic-extension/Utilities.hpp"

using namespace godot;
using namespace OpenVic;

Error GameSingleton::_generate_terrain_texture_array() {
	Error err = OK;
	if (terrain_variants.size() == 0) {
		UtilityFunctions::push_error("Failed to load terrain textures!");
		return FAILED;
	}
	// TerrainVariant count is limited by the data type representing it in the map image
	if (terrain_variants.size() > TerrainVariant::MAX_TERRIN_VARIANT_COUNT) {
		UtilityFunctions::push_error("Too many terrain textures - all after the first ",
			static_cast<uint64_t>(TerrainVariant::MAX_TERRIN_VARIANT_COUNT), " will be ignored");
		err = FAILED;
	}

	Array terrain_images;
	for (size_t i = 0; i < terrain_variants.size() && i < TerrainVariant::MAX_TERRIN_VARIANT_COUNT; ++i) {
		TerrainVariant const& var = *terrain_variants.get_item_by_index(i);
		terrain_images.append(var.get_image());
	}

	terrain_texture.instantiate();
	if (terrain_texture->create_from_images(terrain_images) != OK) {
		UtilityFunctions::push_error("Failed to create terrain texture array!");
		return FAILED;
	}
	return err;
}

Error GameSingleton::_load_map_images(String const& province_image_path, String const& terrain_image_path, bool flip_vertical) {
	if (province_shape_texture.is_valid()) {
		UtilityFunctions::push_error("Map images have already been loaded, cannot load: ", province_image_path, " and ", terrain_image_path);
		return FAILED;
	}

	Error err = OK;

	const Vector2i province_dims {
		static_cast<int32_t>(game_manager.get_map().get_width()),
		static_cast<int32_t>(game_manager.get_map().get_height()) };

	static constexpr int32_t GPU_DIM_LIMIT = 0x3FFF;
	// For each dimension of the image, this finds the small number of equal subdivisions required get the individual texture dims under GPU_DIM_LIMIT
	for (int i = 0; i < 2; ++i)
		for (image_subdivisions[i] = 1; province_dims[i] / image_subdivisions[i] > GPU_DIM_LIMIT ||
			province_dims[i] % image_subdivisions[i] != 0; ++image_subdivisions[i]);

	Map::shape_pixel_t const* province_shape_data = game_manager.get_map().get_province_shape_image().data();
	const Vector2i divided_dims = province_dims / image_subdivisions;
	Array province_shape_images;
	province_shape_images.resize(image_subdivisions.x * image_subdivisions.y);
	for (int32_t v = 0; v < image_subdivisions.y; ++v) {
		for (int32_t u = 0; u < image_subdivisions.x; ++u) {
			PackedByteArray index_data_array;
			index_data_array.resize(divided_dims.x * divided_dims.y * sizeof(Map::shape_pixel_t));

			for (int32_t y = 0; y < divided_dims.y; ++y)
				memcpy(index_data_array.ptrw() + y * divided_dims.x * sizeof(Map::shape_pixel_t),
					province_shape_data + (v * divided_dims.y + y) * province_dims.x + u * divided_dims.x,
					divided_dims.x * sizeof(Map::shape_pixel_t));

			const Ref<Image> province_shape_subimage = Image::create_from_data(divided_dims.x, divided_dims.y, false, Image::FORMAT_RGB8, index_data_array);
			if (province_shape_subimage.is_null()) {
				UtilityFunctions::push_error("Failed to create province shape image (", u, ", ", v, ")");
				err = FAILED;
			}
			province_shape_images[u + v * image_subdivisions.x] = province_shape_subimage;
		}
	}

	province_shape_texture.instantiate();
	if (province_shape_texture->create_from_images(province_shape_images) != OK) {
		UtilityFunctions::push_error("Failed to create terrain texture array!");
		err = FAILED;
	}

	if (_update_colour_image() != OK) err = FAILED;

	return err;
}