use crate::card_loader::*;
use crate::game::*;
use crate::AppState;
use crate::DmUserMethod::*;
use crate::GameHandlerMessage::*;
use crate::SendUserMessage::*;
use crate::UserHandlerMessage::*;
use axum::extract::ws::Message;
use lib::*;
use serde_json::to_string;
use std::{collections::HashMap, net::SocketAddr, sync::Arc};
use tokio::sync::mpsc::Sender;

/// For interacting with the game handler
pub enum GameHandlerMessage {
    NewGame(NewGameRequest, SocketAddr),
    JoinGame(String, SocketAddr),
    MoveRequest(PlayerMoveRequest, SocketAddr),
    JudgeDecision(JudgeDecisionRequest, SocketAddr),
    DeleteGame(GameDeleteRequest),
    SendGameStateUpdate(Vec<String>),
    SendGameMetaUpdate(Vec<String>),
    BroadcastGamesUpdate(),
    SendCardPacks(Sender<Message>),
}

/// Handles game stuff
pub struct GameHandler {
    /// Global state pointer
    state: Arc<AppState>,
    games: HashMap<String, Game>,
    packs: CardPacks,
    packs_meta: CardPacksMeta,
}

impl GameHandler {
    /// Returns a new game handler
    pub fn new(state: Arc<AppState>) -> Self {
        let games = HashMap::new();
        let (packs, packs_meta) = card_loader("data/cah-cards-full.json").unwrap();
        GameHandler {
            state,
            games,
            packs,
            packs_meta,
        }
    }

    /// Handles incoming messages
    pub async fn handle(&mut self, message: GameHandlerMessage) {
        match message {
            NewGame(request, addr) => self.create_new_game(request, addr).await,
            JoinGame(request, addr) => self.join_game(request, addr).await,
            MoveRequest(request, addr) => self.handle_player_move(request, addr),
            JudgeDecision(request, addr) => self.handle_judging(request, addr).await,
            DeleteGame(request) => self.delete_game(request).await,
            SendGameStateUpdate(game_ids) => self.send_game_state_update_all(game_ids),
            SendGameMetaUpdate(game_ids) => self.send_game_meta_update(game_ids),
            BroadcastGamesUpdate() => self.broadcast_game_browser_update(),
            SendCardPacks(tx) => self.send_card_packs(tx).await,
        }
    }

    /// Delete game
    async fn delete_game(&mut self, request: GameDeleteRequest) {
        // TODO: add auth lol
        if self.games.remove(&request.delete_game_id).is_some() {
            self.broadcast_game_browser_update();
        } else {
            tracing::error!("User tried to delete a nonexistent game!");
        }
    }

    /// Process judging
    async fn handle_judging(&mut self, request: JudgeDecisionRequest, addr: SocketAddr) {
        if let Some(this_game) = self.games.get_mut(&request.game_id) {
            if let Some(player_user) = self.state.online_users.read().unwrap().get(&addr) {
                let player_user_id = player_user.read().unwrap().uuid.to_string();
                let game_id = request.game_id.to_string();

                // Send to game
                this_game.judge_round(&request, player_user_id);

                self.send_game_state_update_all(vec![game_id.clone()]);
                self.send_game_meta_update(vec![game_id]);
            } else {
                tracing::error!("Received judge request for nonexistent judge player!");
            }
        } else {
            tracing::error!("Received judge request for nonexistent game!");
        }

        // Send updates for all players
        self.send_game_state_update_all(vec![request.game_id.clone()]);
        self.send_game_meta_update(vec![request.game_id]);
    }

    /// Process player move request
    fn handle_player_move(&mut self, request: PlayerMoveRequest, addr: SocketAddr) {
        if let Some(this_game) = self.games.get_mut(&request.game_id) {
            if let Some(player_user) = self.state.online_users.read().unwrap().get(&addr) {
                let player_user_id = player_user.read().unwrap().uuid.to_string();

                // Do the stuff
                match this_game.player_move(&request, player_user_id) {
                    Err(err) => {
                        let message = ChatMessage { text: err };
                        let users_tx = self.state.tx_user_handler.clone();
                        tokio::spawn(async move {
                            if let Err(e) = users_tx
                                .send(DmUser(SendChatMessage(message), Addr(addr)))
                                .await
                            {
                                tracing::error!("Could not send message: {}", e);
                            }
                        });
                    }
                    Ok(None) => {
                        tracing::debug!("TODO: whatever i'm supposed to do")
                    }
                    Ok(Some((judge_round, czar_id))) => {
                        let users_tx = self.state.tx_user_handler.clone();
                        tokio::spawn(async move {
                            if let Err(e) = users_tx
                                .send(DmUser(SendJudgeRound(judge_round), Id(czar_id)))
                                .await
                            {
                                tracing::error!("Could not send message: {}", e);
                            }
                        });
                    }
                };
            } else {
                tracing::error!("Nonexistent player tried to submit move for game!");
            }
        } else {
            tracing::error!("Player tried to submit move for nonexistent game!");
        }
        self.send_game_meta_update(vec![request.game_id]);
    }

    // Ties game ids to user for easier lookup
    fn register_user_in_game(&self, game_id: String, user_id: String) {
        if !self
            .state
            .games_by_user
            .read()
            .unwrap()
            .contains_key(&user_id)
        {
            self.state
                .games_by_user
                .write()
                .unwrap()
                .insert(user_id, vec![game_id]);
        } else if self
            .state
            .games_by_user
            .read()
            .unwrap()
            .contains_key(&user_id)
        {
            self.state
                .games_by_user
                .write()
                .unwrap()
                .get_mut(&user_id)
                .unwrap()
                .extend(vec![game_id]);
        }
    }

    /// Puts a user in a game
    async fn join_game(&mut self, game_id: String, addr: SocketAddr) {
        if self.games.contains_key(&game_id) {
            if let Some(this_user) = self.state.online_users.read().unwrap().get(&addr) {
                let this_user_id = this_user.read().unwrap().uuid.clone();

                // Register game to user
                self.register_user_in_game(game_id.clone(), this_user_id.clone());

                // Create player
                self.games
                    .get_mut(&game_id)
                    .unwrap()
                    .create_player(this_user.clone());

                // Send cards
                self.send_game_state_update_single(this_user_id, game_id.clone())
            } else {
                tracing::error!("Tried to add a nonexistent user to game!");
                return;
            }
        } else {
            tracing::error!("User tried to join a nonexistent game!");
            return;
        }

        // Send updates for all players
        self.send_game_meta_update(vec![game_id.clone()]);

        self.broadcast_game_browser_update();
        self.broadcast_game_count();
    }

    /// Send game meta update for all players of a game
    fn send_game_meta_update(&self, game_ids: Vec<String>) {
        for game_id in game_ids {
            if let Some(this_game) = self.games.get(&game_id) {
                let players = this_game
                    .players
                    .values()
                    .map(|player| GamePlayerMeta {
                        name: player.user.read().unwrap().name.clone(),
                        score: player.black.len().try_into().unwrap(),
                        submitted: this_game
                            .judge_pile_meta
                            .values()
                            .collect::<Vec<&String>>()
                            .contains(&&player.user.read().unwrap().uuid),
                    })
                    .collect::<Vec<GamePlayerMeta>>();

                for player in this_game.players.values() {
                    // Create update for user's game view
                    let meta = GameMeta {
                        uuid: game_id.clone(),
                        name: this_game.name.clone(),
                        host: this_game.host.read().unwrap().name.clone(),
                        players: players.clone(),
                        czar: this_game.czar.read().unwrap().name.clone(),
                        packs: this_game.packs.clone(),
                        white_count: this_game.white.len().try_into().unwrap(),
                        black_count: this_game.black.len().try_into().unwrap(),
                        white_discard_count: this_game.white_discard.len().try_into().unwrap(),
                    };

                    // Send user's update
                    let msg = Message::Text(to_string(&meta).unwrap());
                    let user_tx = player.user.read().unwrap().tx.clone();
                    tokio::spawn(async move {
                        // channel can still close after this point but it'll catch most of it
                        // TODO: handle this later? make this situation impossible to begin with?
                        if !user_tx.is_closed() {
                            if let Err(e) = user_tx.send(msg).await {
                                tracing::error!("Error sending user update: {}", e)
                            }
                        }
                    });
                }
            } else {
                tracing::error!("Attempted to create game meta update for nonexistent game!");
            }
        }
    }

    /// Send game state update for all players of a game
    fn send_game_state_update_all(&self, game_ids: Vec<String>) {
        for game_id in game_ids {
            if let Some(this_game) = self.games.get(&game_id) {
                for player in this_game.players.values() {
                    // Create update for user's game view
                    let meta = GameStateMeta {
                        black: Some(BlackCardMeta {
                            text: this_game.current_black.text.clone(),
                            pick: this_game.current_black.pick.try_into().unwrap(),
                        }),
                        white: player
                            .white
                            .iter()
                            .map(|card| WhiteCardMeta {
                                uuid: card.uuid.to_string(),
                                text: card.text.clone(),
                            })
                            .collect(),
                    };

                    // Send user's update
                    let msg = Message::Text(to_string(&meta).unwrap());
                    let user_tx = player.user.read().unwrap().tx.clone();
                    tokio::spawn(async move { user_tx.send(msg).await });
                }
            } else {
                tracing::error!("Attempted to create game state update for nonexistent game!");
            }
        }
    }

    /// Send game state update for a single user
    fn send_game_state_update_single(&self, user_id: String, game_id: String) {
        if let Some(this_game) = self.games.get(&game_id) {
            if let Some(player) = this_game.players.get(&user_id) {
                // Create update for user's game view
                let meta = GameStateMeta {
                    black: Some(BlackCardMeta {
                        text: this_game.current_black.text.clone(),
                        pick: this_game.current_black.pick.try_into().unwrap(),
                    }),
                    white: player
                        .white
                        .iter()
                        .map(|card| WhiteCardMeta {
                            uuid: card.uuid.to_string(),
                            text: card.text.clone(),
                        })
                        .collect(),
                };

                // Send user's update
                let msg = Message::Text(to_string(&meta).unwrap());
                let user_tx = player.user.read().unwrap().tx.clone();
                tokio::spawn(async move { user_tx.send(msg).await });
            } else {
                tracing::error!("Attempted to create game state update for nonexistent player!");
            }
        } else {
            tracing::error!("Attempted to create game state update for nonexistent game!");
        }
    }

    /// Creates a new game
    async fn create_new_game(&mut self, new_game: NewGameRequest, addr: SocketAddr) {
        if new_game.game_packs.is_empty() {
            tracing::error!("New game cards are empty!");
            return;
        } else if new_game.game_name.is_empty() {
            tracing::error!("New game name is empty!");
            return;
        }

        if let Some(host) = self.state.online_users.read().unwrap().get(&addr) {
            let new_game_name;
            let max_game_name_len = 32;

            if new_game.game_name.len() > max_game_name_len {
                new_game_name = new_game.game_name[..max_game_name_len].to_string()
            } else {
                new_game_name = new_game.game_name
            }

            // Create manifest
            let manifest = NewGameManifest {
                name: new_game_name,
                host: host.clone(),
                packs: new_game
                    .game_packs
                    .into_iter()
                    .map(|pack| u8::from_str_radix(&pack, 10).unwrap())
                    .collect(),
            };

            // Create game using manifest
            let mut new_game_object = Game::new(&self.packs, manifest);

            // Don't forget to create the host player!!!
            new_game_object.create_player(host.clone());

            let game_id = new_game_object.uuid.to_string();

            // Add game to active list
            self.games
                .insert(new_game_object.uuid.to_string(), new_game_object);

            // Register game to user
            self.register_user_in_game(game_id.clone(), host.read().unwrap().uuid.clone());
            self.send_game_state_update_all(vec![game_id.clone()]);
            self.send_game_meta_update(vec![game_id]);

            self.broadcast_game_browser_update();
            self.broadcast_game_count();
        } else {
            tracing::error!("Attempted to create game for nonexistent player!");
        }
    }

    /// Generate games list update
    fn broadcast_game_browser_update(&self) {
        // TODO: this may get expensive if there are many games

        let games = self
            .games
            .values()
            .map(|game| GameBrowserMeta {
                uuid: game.uuid.to_string(),
                name: game.name.clone(),
                host: game.host.read().unwrap().name.clone(),
                players: game.players.len().try_into().unwrap(),
                packs: game.packs.clone(),
            })
            .collect::<Vec<GameBrowserMeta>>();

        let msg = to_string::<GamesUpdate>(&GamesUpdate { games }).unwrap();
        let tx = self.state.tx_broadcast.clone();
        tokio::spawn(async move {
            if let Err(e) = tx.send(Message::Text(msg)) {
                tracing::error!("Error broadcasting games update: {}", e);
            }
        });
    }

    /// Broadcast updated game count
    fn broadcast_game_count(&self) {
        let tx = self.state.tx_broadcast.clone();
        let active_games: u32 = self.games.len().try_into().unwrap();
        let msg = to_string(&ServerActiveGames { active_games }).unwrap();
        tokio::spawn(async move {
            if let Err(e) = tx.send(Message::Text(msg)) {
                tracing::error!("Error broadcasting game count: {}", e);
            }
        });
    }

    /// Send available card packs to a user
    async fn send_card_packs(&self, tx: Sender<Message>) {
        let msg = Message::Text(to_string::<CardPacksMeta>(&self.packs_meta).unwrap());
        if let Err(e) = tx.send(msg).await {
            tracing::error!("Error sending card packs: {}", e)
        }
    }
}