use std::collections::HashMap;
use std::sync::Arc;

use super::render::render_context::RenderContext;
use super::render::vulkan_context::VulkanContext;
use crate::core::input::InputManager;
use crate::core::scene::SceneManager;
use crate::core::timer::Timer;
use crate::game::main_scene::MainScene;
use egui_winit_vulkano::{Gui, GuiConfig, egui};
use vulkano::command_buffer::{
    AutoCommandBufferBuilder, CommandBufferUsage, RenderingAttachmentInfo, RenderingInfo,
};
use vulkano::pipeline::graphics::viewport::Viewport;
use vulkano::render_pass::{AttachmentLoadOp, AttachmentStoreOp};
use vulkano::swapchain::PresentMode;
use vulkano::sync::GpuFuture;
use vulkano_util::context::VulkanoContext;
use vulkano_util::renderer::VulkanoWindowRenderer;
use vulkano_util::window::{VulkanoWindows, WindowDescriptor};
use winit::application::ApplicationHandler;
use winit::event::WindowEvent;
use winit::event_loop::ActiveEventLoop;
use winit::window::WindowId;

pub struct App {
    vulkan_context: Arc<VulkanContext>,
    vulkano_windows: Arc<VulkanoWindows>,
    gui: HashMap<WindowId, Gui>,
    clear_color: [f32; 3],
    input_manager: InputManager,
    scene_manager: SceneManager,
    timer: Timer,
}

impl From<(&VulkanContext, &VulkanoWindowRenderer)> for RenderContext {
    fn from((vulkan_context, renderer): (&VulkanContext, &VulkanoWindowRenderer)) -> Self {
        RenderContext::new(
            vulkan_context.vulkano_context().instance().clone(),
            vulkan_context.vulkano_context().device().clone(),
            vulkan_context.vulkano_context().graphics_queue().clone(),
            vulkan_context.vulkano_context().compute_queue().clone(),
            vulkan_context.vulkano_context().transfer_queue().cloned(),
            vulkan_context.vulkano_context().memory_allocator().clone(),
            vulkan_context.command_buffer_allocator().clone(),
            vulkan_context.descriptor_set_allocator().clone(),
            renderer.resolution(),
            renderer.aspect_ratio(),
            renderer.swapchain_format(),
        )
    }
}

impl App {
    pub fn new(vulkano_context: VulkanoContext, input_manager: InputManager) -> Self {
        Self {
            vulkan_context: Arc::new(VulkanContext::new(vulkano_context)),
            vulkano_windows: Arc::new(VulkanoWindows::default()),
            gui: HashMap::new(),
            clear_color: [0.0, 0.0, 0.0],
            input_manager,
            scene_manager: SceneManager::new(),
            timer: Timer::new(),
        }
    }
}

impl ApplicationHandler for App {
    fn resumed(&mut self, event_loop: &ActiveEventLoop) {
        if let Some(vulkano_windows) = Arc::get_mut(&mut self.vulkano_windows) {
            let window_id = vulkano_windows.create_window(
                event_loop,
                self.vulkan_context.vulkano_context(),
                &WindowDescriptor {
                    title: "Rust ASH Test".to_string(),
                    width: 800.0,
                    height: 600.0,
                    present_mode: PresentMode::Fifo,
                    ..Default::default()
                },
                |_| {},
            );

            let gui = {
                let renderer = vulkano_windows.get_renderer_mut(window_id).unwrap();
                Gui::new(
                    event_loop,
                    renderer.surface(),
                    renderer.graphics_queue(),
                    renderer.swapchain_format(),
                    GuiConfig {
                        is_overlay: true,
                        ..Default::default()
                    },
                )
            };
            self.gui.insert(window_id, gui);
        }

        self.scene_manager
            .load_scene(Box::new(MainScene::default()));
    }

    fn window_event(&mut self, event_loop: &ActiveEventLoop, id: WindowId, event: WindowEvent) {
        let renderer = Arc::get_mut(&mut self.vulkano_windows)
            .unwrap()
            .get_renderer_mut(id)
            .unwrap();
        let gui = self.gui.get_mut(&id).unwrap();
        let render_context = RenderContext::from((self.vulkan_context.as_ref(), &*renderer));

        if !gui.update(&event) {
            self.input_manager.process_window_event(&event);
        }

        match event {
            WindowEvent::CloseRequested => {
                log::debug!("The close button was pressed; stopping");
                event_loop.exit();
            }
            WindowEvent::Resized(_) => {
                renderer.resize();
            }
            WindowEvent::ScaleFactorChanged { .. } => {
                renderer.resize();
            }
            WindowEvent::RedrawRequested => {
                self.input_manager.update();
                self.timer.update();
                self.scene_manager.load_scene_if_not_loaded(&render_context);
                if let Some(scene) = self.scene_manager.current_scene_mut() {
                    scene.update(&render_context, &self.input_manager, &self.timer);
                }

                let acquire_future = renderer.acquire(None, |_| {}).unwrap();

                let mut builder = AutoCommandBufferBuilder::primary(
                    self.vulkan_context.command_buffer_allocator().clone(),
                    self.vulkan_context
                        .vulkano_context()
                        .graphics_queue()
                        .queue_family_index(),
                    CommandBufferUsage::OneTimeSubmit,
                )
                .unwrap();

                {
                    let viewport = Viewport {
                        offset: [0.0, 0.0],
                        extent: renderer.resolution(),
                        depth_range: 0.0..=1.0,
                    };

                    builder
                        .begin_rendering(RenderingInfo {
                            color_attachments: vec![Some(RenderingAttachmentInfo {
                                load_op: AttachmentLoadOp::Clear,
                                store_op: AttachmentStoreOp::Store,
                                clear_value: Some(self.clear_color.into()),
                                ..RenderingAttachmentInfo::image_view(
                                    renderer.swapchain_image_view().clone(),
                                )
                            })],
                            ..Default::default()
                        })
                        .unwrap()
                        .set_viewport(0, [viewport].into_iter().collect())
                        .unwrap();
                }

                if let Some(scene) = self.scene_manager.current_scene() {
                    scene.render(&render_context, &mut builder);
                }

                builder.end_rendering().unwrap();

                let command_buffer = builder.build().unwrap();

                let render_future = acquire_future
                    .then_execute(
                        self.vulkan_context
                            .vulkano_context()
                            .graphics_queue()
                            .clone(),
                        command_buffer,
                    )
                    .unwrap();

                gui.immediate_ui(|gui| {
                    let ctx = gui.context();

                    egui::Window::new("Informations")
                        .vscroll(true)
                        .show(&ctx, |ui| {
                            ui.label(format!("Resolution: {:?}", renderer.resolution()));
                            ui.color_edit_button_rgb(&mut self.clear_color);

                            ui.label(format!("{:#?}", self.input_manager.get_virtual_input()));

                            ui.label(format!("Delta time: {:?}", self.timer.delta_time()));
                        });
                });

                let render_future =
                    gui.draw_on_image(render_future, renderer.swapchain_image_view());

                renderer.present(render_future.boxed(), true);
            }
            _ => {}
        }
    }

    fn about_to_wait(&mut self, _event_loop: &ActiveEventLoop) {
        let window = self.vulkano_windows.get_primary_window().unwrap();
        window.request_redraw();
    }
}