/*************************************************************************/
/*  terrain_material_cache_pcm.cpp                                       */
/*************************************************************************/
/*                         This file is part of:                         */
/*                          PANDEMONIUM ENGINE                           */
/*             https://github.com/Relintai/pandemonium_engine            */
/*************************************************************************/
/* Copyright (c) 2022-present Péter Magyar.                              */
/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/

#include "terrain_material_cache_pcm.h"

#include "../../texture_packer/texture_packer.h"
#include "scene/resources/material/shader_material.h"
#include "scene/resources/material/spatial_material.h"
#include "scene/resources/texture.h"
#include "terrain_surface.h"
#include "terrain_surface_merger.h"

int TerrainMaterialCachePCM::get_texture_flags() const {
	return _packer->get_texture_flags();
}
void TerrainMaterialCachePCM::set_texture_flags(const int flags) {
	_packer->set_texture_flags(flags);
}

int TerrainMaterialCachePCM::get_max_atlas_size() const {
	return _packer->get_max_atlas_size();
}
void TerrainMaterialCachePCM::set_max_atlas_size(const int size) {
	_packer->set_max_atlas_size(size);
}

bool TerrainMaterialCachePCM::get_keep_original_atlases() const {
	return _packer->get_keep_original_atlases();
}
void TerrainMaterialCachePCM::set_keep_original_atlases(const bool value) {
	_packer->set_keep_original_atlases(value);
}

Color TerrainMaterialCachePCM::get_background_color() const {
	return _packer->get_background_color();
}
void TerrainMaterialCachePCM::set_background_color(const Color &color) {
	_packer->set_background_color(color);
}

int TerrainMaterialCachePCM::get_margin() const {
	return _packer->get_margin();
}
void TerrainMaterialCachePCM::set_margin(const int margin) {
	_packer->set_margin(margin);
}

Ref<AtlasTexture> TerrainMaterialCachePCM::additional_texture_get_atlas_tex(const Ref<Texture> &texture) {
	if (!_packer->contains_texture(texture)) {
		return Ref<AtlasTexture>();
	}

	return _packer->get_texture(texture);
}
Rect2 TerrainMaterialCachePCM::additional_texture_get_uv_rect(const Ref<Texture> &texture) {
	if (!texture.is_valid()) {
		return Rect2(0, 0, 1, 1);
	}

	Ref<AtlasTexture> at = _packer->get_texture(texture);

	if (!at.is_valid()) {
		return Rect2(0, 0, 1, 1);
	}

	Rect2 region = at->get_region();

	Ref<Texture> tex = at->get_atlas();

	if (!tex.is_valid()) {
		return Rect2(0, 0, 1, 1);
	}

	Ref<Image> image = tex->get_data();

	if (!image.is_valid()) {
		return Rect2(0, 0, 1, 1);
	}

	float w = tex->get_width();
	float h = tex->get_height();

	region.position = Size2(region.position.x / w, region.position.y / h);
	region.size = Size2(region.size.x / w, region.size.y / h);

	return region;
}

void TerrainMaterialCachePCM::refresh_rects() {
	bool texture_added = false;
	for (int i = 0; i < _surfaces.size(); i++) {
		Ref<TerrainSurfaceMerger> surface = Ref<TerrainSurfaceMerger>(_surfaces[i]);

		if (surface.is_valid()) {
			for (int j = 0; j < TerrainSurface::TERRAIN_SIDES_COUNT; ++j) {
				Ref<Texture> tex = surface->get_texture(static_cast<TerrainSurface::TerrainSurfaceSides>(j));

				if (!tex.is_valid())
					continue;

				if (!_packer->contains_texture(tex)) {
					texture_added = true;
					surface->set_region(static_cast<TerrainSurface::TerrainSurfaceSides>(j), _packer->add_texture(tex));
				} else {
					surface->set_region(static_cast<TerrainSurface::TerrainSurfaceSides>(j), _packer->get_texture(tex));
				}
			}
		}
	}

	for (int i = 0; i < _additional_textures.size(); i++) {
		Ref<Texture> tex = _additional_textures.get(i);

		ERR_CONTINUE(!tex.is_valid());

		if (!_packer->contains_texture(tex)) {
			_packer->add_texture(tex);
			texture_added = true;
		}
	}

	if (texture_added) {
		_packer->merge();

		ERR_FAIL_COND(_packer->get_texture_count() == 0);

		Ref<Texture> tex = _packer->get_generated_texture(0);

		setup_material_albedo(tex);
	}

	for (int i = 0; i < _surfaces.size(); i++) {
		Ref<TerrainSurfaceMerger> surface = _surfaces[i];

		if (surface.is_valid()) {
			surface->refresh_rects();
		}
	}

	_initialized = true;
}

void TerrainMaterialCachePCM::_setup_material_albedo(Ref<Texture> texture) {
	int count = material_get_num();

	for (int i = 0; i < count; ++i) {
		Ref<Material> m = material_get(i);

		Ref<SpatialMaterial> spmat = m;

		if (spmat.is_valid()) {
			spmat->set_texture(SpatialMaterial::TEXTURE_ALBEDO, texture);
			return;
		}

		Ref<ShaderMaterial> shmat = m;

		if (shmat.is_valid()) {
			shmat->set_shader_param("texture_albedo", texture);
		}
	}
}

TerrainMaterialCachePCM::TerrainMaterialCachePCM() {
	_packer.instance();

	_packer->set_texture_flags(Texture::FLAG_MIPMAPS | Texture::FLAG_FILTER);

	_packer->set_max_atlas_size(1024);
	_packer->set_keep_original_atlases(false);
	_packer->set_margin(0);
}

TerrainMaterialCachePCM::~TerrainMaterialCachePCM() {
	for (int i = 0; i < _surfaces.size(); ++i) {
		Ref<TerrainSurface> surface = _surfaces[i];

		if (surface.is_valid()) {
			surface->set_library(Ref<TerrainLibrary>());
		}
	}

	_surfaces.clear();

	_packer->clear();
	_packer.unref();
}

void TerrainMaterialCachePCM::_bind_methods() {
	ClassDB::bind_method(D_METHOD("get_texture_flags"), &TerrainMaterialCachePCM::get_texture_flags);
	ClassDB::bind_method(D_METHOD("set_texture_flags", "flags"), &TerrainMaterialCachePCM::set_texture_flags);
	ADD_PROPERTY(PropertyInfo(Variant::INT, "texture_flags", PROPERTY_HINT_FLAGS, "Mipmaps,Repeat,Filter,Anisotropic Linear,Convert to Linear,Mirrored Repeat,Video Surface"), "set_texture_flags", "get_texture_flags");

	ClassDB::bind_method(D_METHOD("get_max_atlas_size"), &TerrainMaterialCachePCM::get_max_atlas_size);
	ClassDB::bind_method(D_METHOD("set_max_atlas_size", "size"), &TerrainMaterialCachePCM::set_max_atlas_size);
	ADD_PROPERTY(PropertyInfo(Variant::INT, "max_atlas_size"), "set_max_atlas_size", "get_max_atlas_size");

	ClassDB::bind_method(D_METHOD("get_keep_original_atlases"), &TerrainMaterialCachePCM::get_keep_original_atlases);
	ClassDB::bind_method(D_METHOD("set_keep_original_atlases", "value"), &TerrainMaterialCachePCM::set_keep_original_atlases);
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "keep_original_atlases"), "set_keep_original_atlases", "get_keep_original_atlases");

	ClassDB::bind_method(D_METHOD("get_background_color"), &TerrainMaterialCachePCM::get_background_color);
	ClassDB::bind_method(D_METHOD("set_background_color", "color"), &TerrainMaterialCachePCM::set_background_color);
	ADD_PROPERTY(PropertyInfo(Variant::COLOR, "background_color"), "set_background_color", "get_background_color");

	ClassDB::bind_method(D_METHOD("get_margin"), &TerrainMaterialCachePCM::get_margin);
	ClassDB::bind_method(D_METHOD("set_margin", "size"), &TerrainMaterialCachePCM::set_margin);
	ADD_PROPERTY(PropertyInfo(Variant::INT, "margin"), "set_margin", "get_margin");

	ClassDB::bind_method(D_METHOD("_setup_material_albedo", "texture"), &TerrainMaterialCachePCM::_setup_material_albedo);
}