use anyhow::{Result, anyhow};
use clap::Parser;
use futures_util::{SinkExt, StreamExt};
use hurrycurry_protocol::{
    Gamedata, Hand, Message, PacketC, PacketS, PlayerClass, PlayerID, TileIndex, VERSION,
    glam::{IVec2, Vec2, ivec2},
    movement::MovementBase,
};
use log::{debug, info, warn};
use std::{
    collections::{HashMap, HashSet},
    net::SocketAddr,
    time::Instant,
};
use tokio::net::{TcpListener, TcpStream};

#[derive(Parser)]
struct Args {
    #[arg(short, long, default_value = "127.0.0.1")]
    bind_addr: String,
    #[arg(short, long, default_value = "27035")]
    port: u16,
}

#[derive(Parser)]
#[clap(multicall = true)]
enum Command {
    Play,
}

#[tokio::main]
async fn main() -> Result<()> {
    env_logger::init_from_env("LOG");
    let args = Args::parse();
    let ws_listener = TcpListener::bind((args.bind_addr, args.port)).await?;
    loop {
        let (sock, addr) = ws_listener.accept().await?;
        if let Err(e) = handle_conn(sock, addr).await {
            warn!("client error: {e}");
        }
    }
}

const TILES: &[&str] = &[
    "grass",
    "floor",
    "counter",
    "oven",
    "stove",
    "cuttingboard",
    "chair",
    "table",
];

#[allow(unused_assignments)]
async fn handle_conn(sock: TcpStream, addr: SocketAddr) -> Result<()> {
    let sock = tokio_tungstenite::accept_async(sock).await?;
    info!("{addr} connected via websocket");

    let mut state = State {
        out: Vec::new(),
        tiles: HashMap::new(),
        walkable: HashSet::new(),
        joined: false,
        movement: MovementBase::new(Vec2::ZERO),
        last_movement: Instant::now(),
        tile: TileIndex(0),
    };

    state.out.push(PacketC::Version {
        major: VERSION.0,
        minor: VERSION.1,
        supports_bincode: false,
    });
    state.out.push(PacketC::Data {
        data: Gamedata {
            tile_collide: TILES.iter().map(|_| false).collect(),
            tile_interact: TILES.iter().map(|_| true).collect(),
            tile_names: TILES.iter().map(|s| s.to_string()).collect(),
            current_map: "editor".to_owned(),
            ..Default::default()
        },
    });
    state.out.push(PacketC::SetIngame {
        state: true,
        lobby: false, // very ironic
    });

    state.build_start_platform();

    let (mut write, mut read) = sock.split();

    loop {
        for p in state.out.drain(..) {
            debug!("-> {p:?}");
            write
                .send(tokio_tungstenite::tungstenite::Message::Text(
                    serde_json::to_string(&p).unwrap(),
                ))
                .await?;
        }

        let Some(message) = read.next().await.transpose()? else {
            break;
        };
        let packet = match message {
            tokio_tungstenite::tungstenite::Message::Text(line) => {
                match serde_json::from_str::<PacketS>(&line) {
                    Ok(p) => p,
                    Err(e) => {
                        warn!("Invalid json packet: {e}");
                        break;
                    }
                }
            }
            tokio_tungstenite::tungstenite::Message::Close(_) => break,
            _ => continue,
        };
        debug!("<- {packet:?}");

        if let Err(e) = state.handle_packet(packet) {
            state.out.push(PacketC::ServerMessage {
                message: Message::Text(format!("{e}")),
                error: true,
            });
        }
    }
    Ok(())
}

struct State {
    tiles: HashMap<IVec2, TileIndex>,
    walkable: HashSet<IVec2>,
    out: Vec<PacketC>,
    joined: bool,
    movement: MovementBase,
    last_movement: Instant,
    tile: TileIndex,
}

impl State {
    pub fn set_tile(&mut self, pos: IVec2, tile: TileIndex) {
        self.tiles.insert(pos, tile);
        self.walkable.insert(pos);
        self.out.push(PacketC::UpdateMap {
            tile: pos,
            kind: Some(tile),
            neighbors: [
                self.tiles.get(&(pos + IVec2::NEG_Y)).copied(),
                self.tiles.get(&(pos + IVec2::NEG_X)).copied(),
                self.tiles.get(&(pos + IVec2::Y)).copied(),
                self.tiles.get(&(pos + IVec2::X)).copied(),
            ],
        })
    }
    pub fn flush(&mut self) {
        // send every existing tile once move because client does not remember
        // TODO remove when client is fixed
        for (tile, _) in &self.tiles {
            self.out.push(PacketC::UpdateMap {
                tile: *tile,
                kind: None,
                neighbors: [None; 4],
            })
        }
        for (tile, kind) in &self.tiles {
            self.out.push(PacketC::UpdateMap {
                tile: *tile,
                kind: Some(*kind),
                neighbors: [
                    self.tiles.get(&(tile + IVec2::NEG_Y)).copied(),
                    self.tiles.get(&(tile + IVec2::NEG_X)).copied(),
                    self.tiles.get(&(tile + IVec2::Y)).copied(),
                    self.tiles.get(&(tile + IVec2::X)).copied(),
                ],
            })
        }
        self.out.push(PacketC::FlushMap);
    }
    pub fn build_start_platform(&mut self) {
        for x in 0..10 {
            for y in 0..10 {
                self.set_tile(ivec2(x, y), TileIndex(1));
            }
        }
        self.flush();
    }

    pub fn handle_packet(&mut self, packet: PacketS) -> Result<()> {
        match packet {
            PacketS::Join {
                character, name, ..
            } if !self.joined => {
                self.out.push(PacketC::Joined { id: PlayerID(0) });
                self.out.push(PacketC::AddPlayer {
                    id: PlayerID(0),
                    position: self.movement.position,
                    class: PlayerClass::Chef,
                    character,
                    name,
                });
                self.joined = true;
            }
            PacketS::Leave { .. } if self.joined => {
                self.out.push(PacketC::RemovePlayer { id: PlayerID(0) });
                self.joined = false;
            }
            PacketS::Movement {
                player,
                dir,
                boost,
                pos,
            } => {
                let dt = self.last_movement.elapsed();
                self.last_movement += dt;
                self.movement.position = pos.unwrap_or(self.movement.position);
                self.movement.input(dir, boost);
                self.movement.update(&self.walkable, dt.as_secs_f32());
                self.out.push(self.movement.movement_packet_c(player));
            }
            PacketS::Communicate {
                message: Some(Message::Text(t)),
                ..
            } => {
                self.handle_command(
                    Command::try_parse_from(
                        shlex::split(&t)
                            .ok_or(anyhow!("invalid quoting"))?
                            .into_iter(),
                    )
                    .map_err(|e| anyhow!("{e}"))?,
                )?;
            }
            PacketS::Interact {
                hand: Hand(1),
                pos: Some(_),
                ..
            } => {
                self.tile.0 += 1;
                self.tile.0 %= TILES.len();
                self.out.push(PacketC::ServerMessage {
                    message: Message::Text(format!("tile brush: {}", TILES[self.tile.0])),
                    error: false,
                });
            }
            PacketS::Interact {
                hand: Hand(0),
                pos: Some(_),
                ..
            } => {
                let bpos = self.movement.position.floor().as_ivec2();
                self.set_tile(bpos, self.tile);
                for off in [IVec2::NEG_X, IVec2::NEG_Y, IVec2::X, IVec2::Y] {
                    if !self.tiles.contains_key(&(bpos + off)) {
                        self.set_tile(bpos + off, self.tile);
                    }
                }
                self.flush();
            }
            _ => (),
        }
        Ok(())
    }

    pub fn handle_command(&mut self, command: Command) -> Result<()> {
        match command {
            Command::Play => {
                self.out.push(PacketC::Redirect {
                    uri: vec!["ws://127.0.0.1:27032".to_string()],
                });
            }
        }
        Ok(())
    }
}