/*
 * Copyright (C) 2023  Christopher J. Howard
 *
 * This file is part of Antkeeper source code.
 *
 * Antkeeper source code is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Antkeeper source code is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Antkeeper source code.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "game/menu.hpp"
#include <engine/scene/text.hpp>
#include <engine/animation/animation.hpp>
#include <engine/animation/animator.hpp>
#include <engine/animation/ease.hpp>
#include <engine/config.hpp>
#include <algorithm>
#include <engine/math/vector.hpp>

namespace menu {

void init_menu_item_index(::game& ctx, hash::fnv1a32_t menu_name)
{
	if (auto it = ctx.menu_item_indices.find(menu_name); it != ctx.menu_item_indices.end())
	{
		ctx.menu_item_index = &it->second;
	}
	else
	{
		ctx.menu_item_index = &ctx.menu_item_indices[menu_name];
		*ctx.menu_item_index = 0;
	}
}

void update_text_font(::game& ctx)
{
	for (auto [name, value]: ctx.menu_item_texts)
	{
		name->set_material(ctx.menu_font_material);
		name->set_font(&ctx.menu_font);
		
		if (value)
		{
			value->set_material(ctx.menu_font_material);
			value->set_font(&ctx.menu_font);
		}
	}
}

void update_text_color(::game& ctx)
{
	for (std::size_t i = 0; i < ctx.menu_item_texts.size(); ++i)
	{
		auto [name, value] = ctx.menu_item_texts[i];
		
		const math::fvec4& color = (i == *ctx.menu_item_index) ? config::menu_active_color : config::menu_inactive_color;
		
		name->set_color(color);
		if (value)
			value->set_color(color);
	}
}

void align_text(::game& ctx, bool center, bool has_back, float anchor_y)
{
	
	
	const math::fvec2 viewport_size = math::fvec2(ctx.window->get_viewport_size());
	const math::fvec2 viewport_center = viewport_size * 0.5f;
	
	const float viewport_padding = viewport_size.y() * (1.0f / 9.0f);
	
	// Calculate menu width
	float m_width = ctx.menu_font.get_glyph_metrics(U'M').width;
	float column_spacing = m_width * 2.0f;
	const float min_two_column_row_width = m_width * 18.0f;
	float menu_width = 0.0f;
	
	for (auto [name, value]: ctx.menu_item_texts)
	{
		float row_width = 0.0f;
		
		// Add name width to row width
		const auto& name_bounds = name->get_bounds();
		row_width += name_bounds.max.x() - name_bounds.min.x();
		
		if (value)
		{
			// Add value width to row width
			const auto& value_bounds = value->get_bounds();
			row_width += value_bounds.max.x() - value_bounds.min.x();
			
			// Add column spacing to row width
			row_width += column_spacing;
			
			row_width = std::max<float>(min_two_column_row_width, row_width);
		}
		
		menu_width = std::max<float>(menu_width, row_width);
	}
	
	// Align texts
	float menu_height;
	if (has_back)
		menu_height = (ctx.menu_item_texts.size() - 1) * ctx.menu_font.get_font_metrics().linespace - ctx.menu_font.get_font_metrics().linegap;
	else
		menu_height = ctx.menu_item_texts.size() * ctx.menu_font.get_font_metrics().linespace - ctx.menu_font.get_font_metrics().linegap;
	
	float menu_x = viewport_center.x() - menu_width * 0.5f;
	float menu_y = viewport_center.y() + anchor_y + menu_height * 0.5f - ctx.menu_font.get_font_metrics().size;
	
	for (std::size_t i = 0; i < ctx.menu_item_texts.size(); ++i)
	{
		auto [name, value] = ctx.menu_item_texts[i];
		
		float x = menu_x;
		float y = menu_y - ctx.menu_font.get_font_metrics().linespace * i;
		if (has_back && i == ctx.menu_item_texts.size() - 1)
		{
			y = viewport_padding;// + ctx.menu_font.get_font_metrics().linespace;
		}
		
		if (center || i == ctx.menu_item_texts.size() - 1)
		{
			const auto& name_bounds = name->get_bounds();
			const float name_width =  name_bounds.max.x() - name_bounds.min.x();
			x = viewport_center.x() - name_width * 0.5f;
		}
		
		name->set_translation({std::round(x), std::round(y), 0.0f});
		
		if (value)
		{
			const auto& value_bounds = value->get_bounds();
			const float value_width =  value_bounds.max.x() - value_bounds.min.x();
			
			if (center || i == ctx.menu_item_texts.size() - 1)
				x = viewport_center.x() - value_width * 0.5f;
			else
				x = menu_x + menu_width - value_width;
			
			value->set_translation({std::round(x), std::round(y), 0.0f});
		}
	}
}

void refresh_text(::game& ctx)
{
	for (auto [name, value]: ctx.menu_item_texts)
	{
		name->refresh();
		if (value)
			value->refresh();
	}
}

void add_text_to_ui(::game& ctx)
{
	for (auto [name, value]: ctx.menu_item_texts)
	{
		ctx.ui_scene->add_object(*name);
		if (value)
			ctx.ui_scene->add_object(*value);
	}
}

void remove_text_from_ui(::game& ctx)
{
	for (auto [name, value]: ctx.menu_item_texts)
	{
		ctx.ui_scene->remove_object(*name);
		if (value)
			ctx.ui_scene->remove_object(*value);
	}
}

void delete_text(::game& ctx)
{
	ctx.menu_item_texts.clear();
}

void delete_animations(::game& ctx)
{
	ctx.animator->remove_animation(ctx.menu_fade_animation.get());
	ctx.menu_fade_animation.reset();
}

void clear_callbacks(::game& ctx)
{
	// Clear menu item callbacks
	ctx.menu_left_callbacks.clear();
	ctx.menu_right_callbacks.clear();
	ctx.menu_select_callbacks.clear();
	ctx.menu_back_callback = nullptr;
}

void setup_animations(::game& ctx)
{
	ctx.menu_fade_animation = std::make_unique<animation<float>>();
	animation_channel<float>* opacity_channel = ctx.menu_fade_animation->add_channel(0);
	
	ctx.menu_fade_animation->set_frame_callback
	(
		[&ctx](int channel, const float& opacity)
		{
			for (std::size_t i = 0; i < ctx.menu_item_texts.size(); ++i)
			{
				auto [name, value] = ctx.menu_item_texts[i];
				
				math::fvec4 color = (i == *ctx.menu_item_index) ? config::menu_active_color : config::menu_inactive_color;
				color[3] = color[3] * opacity;
				
				if (name)
					name->set_color(color);
				if (value)
					value->set_color(color);
			}
		}
	);
	
	ctx.animator->add_animation(ctx.menu_fade_animation.get());
}

void fade_in(::game& ctx, const std::function<void()>& end_callback)
{
	ctx.menu_fade_animation->set_interpolator(ease<float>::out_cubic);
	animation_channel<float>* opacity_channel = ctx.menu_fade_animation->get_channel(0);
	opacity_channel->remove_keyframes();
	opacity_channel->insert_keyframe({0.0f, 0.0f});
	opacity_channel->insert_keyframe({config::menu_fade_in_duration, 1.0f});
	ctx.menu_fade_animation->set_end_callback(end_callback);
	
	for (std::size_t i = 0; i < ctx.menu_item_texts.size(); ++i)
	{
		auto [name, value] = ctx.menu_item_texts[i];
		
		math::fvec4 color = (i == *ctx.menu_item_index) ? config::menu_active_color : config::menu_inactive_color;
		color[3] = 0.0f;
		
		if (name)
		{
			name->set_color(color);
		}
		if (value)
		{
			value->set_color(color);
		}
	}
	
	ctx.menu_fade_animation->stop();
	ctx.menu_fade_animation->play();
}

void fade_out(::game& ctx, const std::function<void()>& end_callback)
{
	ctx.menu_fade_animation->set_interpolator(ease<float>::out_cubic);
	animation_channel<float>* opacity_channel = ctx.menu_fade_animation->get_channel(0);
	opacity_channel->remove_keyframes();
	opacity_channel->insert_keyframe({0.0f, 1.0f});
	opacity_channel->insert_keyframe({config::menu_fade_out_duration, 0.0f});
	ctx.menu_fade_animation->set_end_callback(end_callback);
	
	ctx.menu_fade_animation->stop();
	ctx.menu_fade_animation->play();
}

void fade_in_bg(::game& ctx)
{
	ctx.menu_bg_fade_out_animation->stop();
	ctx.menu_bg_fade_in_animation->stop();
	ctx.menu_bg_fade_in_animation->play();
}

void fade_out_bg(::game& ctx)
{
	ctx.menu_bg_fade_in_animation->stop();
	ctx.menu_bg_fade_out_animation->stop();
	ctx.menu_bg_fade_out_animation->play();
}

} // namespace menu