/*
    wearechat - generic multiplayer game with voip
    Copyright (C) 2025 metamuffin

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, version 3 of the License only.

    This program 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 Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/
use crate::{camera::Camera, download::Downloader, network::Network, renderer::Renderer};
use anyhow::{Context, Result};
use glam::{Vec2, Vec3};
use log::{info, warn};
use std::{net::TcpStream, sync::Arc, time::Instant};
use weareshared::{
    packets::{Packet, Resource},
    resources::PrefabIndex,
    store::ResourceStore,
    tree::SceneTree,
};
use winit::event::MouseButton;

pub struct State<'a> {
    pub network: Arc<Network>,
    pub downloader: Arc<Downloader>,
    pub renderer: Renderer<'a>,
    pub tree: SceneTree,
    pub camera: Camera,
    pub input_state: InputState,

    pub prefab_index: Arc<PrefabIndex>,
    pub prefab_index_res_loaded: Option<Resource<PrefabIndex>>,
    pub prefab_index_res: Option<Resource<PrefabIndex>>,
}

pub struct InputState {
    time: Instant,
    pub move_dir: Vec3,
    pub mouse_acc: Vec2,
    pub cursor_pos: Vec2,
    pub egui_events: Vec<egui::Event>,
}

impl<'a> State<'a> {
    pub fn new(conn: TcpStream, window: &'a winit::window::Window) -> Result<State<'a>> {
        info!("new state");
        let downloader = Arc::new(Downloader::new(ResourceStore::new_memory()));
        Ok(Self {
            camera: Camera::new(),
            network: Network::new(conn).into(),
            tree: SceneTree::default(),
            renderer: Renderer::new(window, downloader.clone())?,
            downloader,
            input_state: InputState {
                time: Instant::now(),
                move_dir: Vec3::ZERO,
                mouse_acc: Vec2::ZERO,
                cursor_pos: Vec2::ZERO,
                egui_events: Vec::new(),
            },
            prefab_index_res: None,
            prefab_index_res_loaded: None,
            prefab_index: PrefabIndex::default().into(),
        })
    }
    pub fn draw(&mut self) {
        if let Err(e) = self
            .renderer
            .draw(&self.tree, &self.camera, &self.input_state)
        {
            warn!("draw failed: {e:?}");
        }
    }
    pub fn resize(&mut self, width: u32, height: u32) {
        self.renderer.resize(width, height);
        self.camera.aspect = width as f32 / height as f32;
    }
    pub fn click(&mut self, button: MouseButton, down: bool) {
        self.input_state
            .egui_events
            .push(egui::Event::PointerButton {
                pos: egui::Pos2::new(self.input_state.cursor_pos.x, self.input_state.cursor_pos.y),
                button: match button {
                    MouseButton::Left => egui::PointerButton::Primary,
                    MouseButton::Right => egui::PointerButton::Secondary,
                    MouseButton::Middle => egui::PointerButton::Middle,
                    MouseButton::Back => egui::PointerButton::Extra1,
                    MouseButton::Forward => egui::PointerButton::Extra2,
                    MouseButton::Other(_) => egui::PointerButton::Extra1,
                },
                pressed: down,
                modifiers: egui::Modifiers::default(),
            });

        if !down || button != MouseButton::Right {
            return;
        }
        let pi = self.prefab_index.clone();
        self.renderer
            .ui_renderer
            .add_surface(self.camera.new_ui_affine(), move |ctx| {
                let mut open = true;
                egui::Window::new("Prefab Index")
                    .open(&mut open)
                    .show(ctx, |ui| {
                        for (key, _res) in &pi.0 {
                            ui.horizontal(|ui| {
                                ui.label(key);
                                if ui.button("Add").clicked() {}
                            });
                        }
                    });
                open
            });
    }
    pub fn update(&mut self) -> Result<()> {
        let now = Instant::now();
        let dt = (now - self.input_state.time).as_secs_f32();
        self.input_state.time = now;

        self.camera
            .update(self.input_state.move_dir, self.input_state.mouse_acc, dt);
        self.input_state.mouse_acc = Vec2::ZERO;

        for p in self.network.packet_recv.try_iter() {
            self.downloader.packet(&p)?;
            self.tree.packet(&p);
            if let Packet::PrefabIndex(res) = &p {
                self.prefab_index_res = Some(res.to_owned());
            }
        }
        self.downloader
            .update(&self.network)
            .context("downloader state")?;

        if self.prefab_index_res != self.prefab_index_res_loaded {
            if let Some(res) = &self.prefab_index_res {
                if let Some(index) = self.downloader.try_get(res.to_owned())? {
                    info!("prefab index loaded");
                    self.prefab_index = index.into();
                    self.prefab_index_res_loaded = Some(res.to_owned());
                }
            }
        }

        self.input_state.egui_events.clear();
        Ok(())
    }
}