use mio;

use super::common::rnd_reply;

use crate::utils::to_engine_msg;

use crate::{

    core::{

        room::{HwRoom, RoomFlags, MAX_TEAMS_IN_ROOM},

        server::HwServer,

        types,

        types::{ClientId, GameCfg, RoomId, VoteType, Voting, MAX_HEDGEHOGS_PER_TEAM},

    },

    protocol::messages::{

        add_flags, remove_flags, server_chat, HwProtocolMessage, HwServerMessage::*,

        ProtocolFlags as Flags,

    },

    utils::is_name_illegal,

};

use base64::{decode, encode};

use log::*;

use std::{cmp::min, iter::once, mem::swap};

#[derive(Clone)]

struct ByMsg<'a> {

    messages: &'a [u8],

}

impl<'a> Iterator for ByMsg<'a> {

    type Item = &'a [u8];

    fn next(&mut self) -> Option<<Self as Iterator>::Item> {

        if let Some(size) = self.messages.get(0) {

            let (msg, next) = self.messages.split_at(*size as usize + 1);

            self.messages = next;

            Some(msg)

        } else {

            None

        }

    }

}

fn by_msg(source: &[u8]) -> ByMsg {

    ByMsg { messages: source }

}

const VALID_MESSAGES: &[u8] =

    b"M#+LlRrUuDdZzAaSjJ,NpPwtgfhbc12345\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8A";

const NON_TIMED_MESSAGES: &[u8] = b"M#hb";

#[cfg(canhazslicepatterns)]

fn is_msg_valid(msg: &[u8], team_indices: &[u8]) -> bool {

    match msg {

        [size, typ, body..MAX] => {

            VALID_MESSAGES.contains(typ)

                && match body {

                    [1..=MAX_HEDGEHOGS_PER_TEAM, team, ..] if *typ == b'h' => {

                        team_indices.contains(team)

                    }

                    _ => *typ != b'h',

                }

        }

        _ => false,

    }

}

fn is_msg_valid(msg: &[u8], _team_indices: &[u8]) -> bool {

    if let Some(typ) = msg.get(1) {

        VALID_MESSAGES.contains(typ)

    } else {

        false

    }

}

fn is_msg_empty(msg: &[u8]) -> bool {

    msg.get(1).filter(|t| **t == b'+').is_some()

}

fn is_msg_timed(msg: &[u8]) -> bool {

    msg.get(1)

        .filter(|t| !NON_TIMED_MESSAGES.contains(t))

        .is_some()

}

fn voting_description(kind: &VoteType) -> String {

    format!(

        "New voting started: {}",

        match kind {

            VoteType::Kick(nick) => format!("kick {}", nick),

            VoteType::Map(name) => format!("map {}", name.as_ref().unwrap()),

            VoteType::Pause => "pause".to_string(),

            VoteType::NewSeed => "new seed".to_string(),

            VoteType::HedgehogsPerTeam(number) => format!("hedgehogs per team: {}", number),

        }

    )

}

fn room_message_flag(msg: &HwProtocolMessage) -> RoomFlags {

    use crate::protocol::messages::HwProtocolMessage::*;

    match msg {

        ToggleRestrictJoin => RoomFlags::RESTRICTED_JOIN,

        ToggleRestrictTeams => RoomFlags::RESTRICTED_TEAM_ADD,

        ToggleRegisteredOnly => RoomFlags::RESTRICTED_UNREGISTERED_PLAYERS,

        _ => RoomFlags::empty(),

    }

}

pub fn handle(

    server: &mut HwServer,

    client_id: ClientId,

    response: &mut super::Response,

    room_id: RoomId,

    message: HwProtocolMessage,

) {

    let client = &mut server.clients[client_id];

    let room = &mut server.rooms[room_id];

    use crate::protocol::messages::HwProtocolMessage::*;

    match message {

        Part(msg) => {

            let msg = match msg {

                Some(s) => format!("part: {}", s),

                None => "part".to_string(),

            };

            super::common::exit_room(server, client_id, response, &msg);

        }

        Chat(msg) => {

            response.add(

                ChatMsg {

                    nick: client.nick.clone(),

                    msg,

                }

                .send_all()

                .in_room(room_id),

            );

        }

        TeamChat(msg) => {

            let room = &server.rooms[room_id];

            if let Some(ref info) = room.game_info {

                if let Some(clan_color) = room.find_team_color(client_id) {

                    let client = &server.clients[client_id];

                    let engine_msg =

                        to_engine_msg(format!("b{}]{}\x20\x20", client.nick, msg).bytes());

                    let team = room.clan_team_owners(clan_color).collect();

                    response.add(ForwardEngineMessage(vec![engine_msg]).send_many(team))

                }

            }

        }

        Fix => {

            if client.is_admin() {

                room.set_is_fixed(true);

                room.set_join_restriction(false);

                room.set_team_add_restriction(false);

                room.set_unregistered_players_restriction(true);

            }

        }

        Unfix => {

            if client.is_admin() {

                room.set_is_fixed(false);

            }

        }

        Greeting(text) => {

            if client.is_admin() || client.is_master() && !room.is_fixed() {

                room.greeting = text.unwrap_or(String::new());

            }

        }

        MaxTeams(count) => {

            if !client.is_master() {

                response.add(Warning("You're not the room master!".to_string()).send_self());

            } else if !(2..=MAX_TEAMS_IN_ROOM).contains(&count) {

                response

                    .add(Warning("/maxteams: specify number from 2 to 8".to_string()).send_self());

            } else {

                server.rooms[room_id].max_teams = count;

            }

        }

        RoomName(new_name) => {

            if is_name_illegal(&new_name) {

                response.add(Warning("Illegal room name! A room name must be between 1-40 characters long, must not have a trailing or leading space and must not have any of these characters: $()*+?[]^{|}".to_string()).send_self());

            } else if server.has_room(&new_name) {

                response.add(

                    Warning("A room with the same name already exists.".to_string()).send_self(),

                );

            } else {

                let room = &mut server.rooms[room_id];

                if room.is_fixed() || room.master_id != Some(client_id) {

                    response.add(Warning("Access denied.".to_string()).send_self());

                } else {

                    let mut old_name = new_name.clone();

                    let client = &server.clients[client_id];

                    swap(&mut room.name, &mut old_name);

                    super::common::get_room_update(Some(old_name), room, Some(&client), response);

                }

            }

        }

        ToggleReady => {

            let flags = if client.is_ready() {

                room.ready_players_number -= 1;

                remove_flags(&[Flags::Ready])

            } else {

                room.ready_players_number += 1;

                add_flags(&[Flags::Ready])

            };

            let msg = if client.protocol_number < 38 {

                LegacyReady(client.is_ready(), vec![client.nick.clone()])

            } else {

                ClientFlags(flags, vec![client.nick.clone()])

            };

            response.add(msg.send_all().in_room(room.id));

            client.set_is_ready(!client.is_ready());

            if room.is_fixed() && room.ready_players_number == room.players_number {

                super::common::start_game(server, room_id, response);

            }

        }

        AddTeam(mut info) => {

            if room.teams.len() >= room.max_teams as usize {

                response.add(Warning("Too many teams!".to_string()).send_self());

            } else if room.addable_hedgehogs() == 0 {

                response.add(Warning("Too many hedgehogs!".to_string()).send_self());

            } else if room.find_team(|t| t.name == info.name) != None {

                response.add(

                    Warning("There's already a team with same name in the list.".to_string())

                        .send_self(),

                );

            } else if room.game_info.is_some() {

                response.add(

                    Warning("Joining not possible: Round is in progress.".to_string()).send_self(),

                );

            } else if room.is_team_add_restricted() {

                response.add(

                    Warning("This room currently does not allow adding new teams.".to_string())

                        .send_self(),

                );

            } else {

                info.owner = client.nick.clone();

                let team = room.add_team(client.id, *info, client.protocol_number < 42);

                client.teams_in_game += 1;

                client.clan = Some(team.color);

                response.add(TeamAccepted(team.name.clone()).send_self());

                response.add(

                    TeamAdd(team.to_protocol())

                        .send_all()

                        .in_room(room_id)

                        .but_self(),

                );

                response.add(

                    TeamColor(team.name.clone(), team.color)

                        .send_all()

                        .in_room(room_id),

                );

                response.add(

                    HedgehogsNumber(team.name.clone(), team.hedgehogs_number)

                        .send_all()

                        .in_room(room_id),

                );

                let room_master = if let Some(id) = room.master_id {

                    Some(&server.clients[id])

                } else {

                    None

                };

                super::common::get_room_update(None, room, room_master, response);

            }

        }

        RemoveTeam(name) => match room.find_team_owner(&name) {

            None => response.add(

                Warning("Error: The team you tried to remove does not exist.".to_string())

                    .send_self(),

            ),

            Some((id, _)) if id != client_id => response

                .add(Warning("You can't remove a team you don't own.".to_string()).send_self()),

            Some((_, name)) => {

                client.teams_in_game -= 1;

                client.clan = room.find_team_color(client.id);

                let names = vec![name.to_string()];

                super::common::remove_teams(room, names, client.is_in_game(), response);

                match room.game_info {

                    Some(ref info) if info.teams_in_game == 0 => {

                        super::common::end_game(server, room_id, response)

                    }

                    _ => (),

                }

            }

        },

        SetHedgehogsNumber(team_name, number) => {

            let addable_hedgehogs = room.addable_hedgehogs();

            if let Some((_, team)) = room.find_team_and_owner_mut(|t| t.name == team_name) {

                let max_hedgehogs = min(

                    MAX_HEDGEHOGS_PER_TEAM,

                    addable_hedgehogs + team.hedgehogs_number,

                );

                if !client.is_master() {

                    response.add(Error("You're not the room master!".to_string()).send_self());

                } else if !(1..=max_hedgehogs).contains(&number) {

                    response

                        .add(HedgehogsNumber(team.name.clone(), team.hedgehogs_number).send_self());

                } else {

                    team.hedgehogs_number = number;

                    response.add(

                        HedgehogsNumber(team.name.clone(), number)

                            .send_all()

                            .in_room(room_id)

                            .but_self(),

                    );

                }

            } else {

                response.add(Warning("No such team.".to_string()).send_self());

            }

        }

        SetTeamColor(team_name, color) => {

            if let Some((owner, team)) = room.find_team_and_owner_mut(|t| t.name == team_name) {

                if !client.is_master() {

                    response.add(Error("You're not the room master!".to_string()).send_self());

                } else {

                    team.color = color;

                    response.add(

                        TeamColor(team.name.clone(), color)

                            .send_all()

                            .in_room(room_id)

                            .but_self(),

                    );

                    server.clients[owner].clan = Some(color);

                }

            } else {

                response.add(Warning("No such team.".to_string()).send_self());

            }

        }

        Cfg(cfg) => {

            if room.is_fixed() {

                response.add(Warning("Access denied.".to_string()).send_self());

            } else if !client.is_master() {

                response.add(Error("You're not the room master!".to_string()).send_self());

            } else {

                let cfg = match cfg {

                    GameCfg::Scheme(name, mut values) => {

                        if client.protocol_number == 49 && values.len() >= 2 {

                            let mut s = "X".repeat(50);

                            s.push_str(&values.pop().unwrap());

                            values.push(s);

                        }

                        GameCfg::Scheme(name, values)

                    }

                    cfg => cfg,

                };

                response.add(cfg.to_server_msg().send_all().in_room(room.id).but_self());

                room.set_config(cfg);

            }

        }

        Save(name, location) => {

            response.add(

                server_chat(format!("Room config saved as {}", name))

                    .send_all()

                    .in_room(room_id),

            );

            room.save_config(name, location);

        }

        #[cfg(feature = "official-server")]

        SaveRoom(filename) => {

            if client.is_admin() {

                match room.get_saves() {

                    Ok(contents) => response.request_io(super::IoTask::SaveRoom {

                        room_id,

                        filename,

                        contents,

                    }),

                    Err(e) => {

                        warn!("Error while serializing the room configs: {}", e);

                        response.add(

                            Warning("Unable to serialize the room configs.".to_string())

                                .send_self(),

                        )

                    }

                }

            }

        }

        #[cfg(feature = "official-server")]

        LoadRoom(filename) => {

            if client.is_admin() {

                response.request_io(super::IoTask::LoadRoom { room_id, filename });

            }

        }

        Delete(name) => {

            if !room.delete_config(&name) {

                response.add(Warning(format!("Save doesn't exist: {}", name)).send_self());

            } else {

                response.add(

                    server_chat(format!("Room config {} has been deleted", name))

                        .send_all()

                        .in_room(room_id),

                );

            }

        }

        CallVote(None) => {

            response.add(server_chat("Available callvote commands: kick <nickname>, map <name>, pause, newseed, hedgehogs <number>".to_string())

                .send_self());

        }

        CallVote(Some(kind)) => {

            let is_in_game = room.game_info.is_some();

            let error = match &kind {

                VoteType::Kick(nick) => {

                    if server

                        .find_client(&nick)

                        .filter(|c| c.room_id == Some(room_id))

                        .is_some()

                    {

                        None

                    } else {

                        Some("/callvote kick: No such user!".to_string())

                    }

                }

                VoteType::Map(None) => {

                    let names: Vec<_> = server.rooms[room_id].saves.keys().cloned().collect();

                    if names.is_empty() {

                        Some("/callvote map: No maps saved in this room!".to_string())

                    } else {

                        Some(format!("Available maps: {}", names.join(", ")))

                    }

                }

                VoteType::Map(Some(name)) => {

                    if room.saves.get(&name[..]).is_some() {

                        None

                    } else {

                        Some("/callvote map: No such map!".to_string())

                    }

                }

                VoteType::Pause => {

                    if is_in_game {

                        None

                    } else {

                        Some("/callvote pause: No game in progress!".to_string())

                    }

                }

                VoteType::NewSeed => None,

                VoteType::HedgehogsPerTeam(number) => match number {

                    1..=MAX_HEDGEHOGS_PER_TEAM => None,

                    _ => Some("/callvote hedgehogs: Specify number from 1 to 8.".to_string()),

                },

            };

            match error {

                None => {

                    let msg = voting_description(&kind);

                    let voting = Voting::new(kind, server.room_clients(client_id).collect());

                    let room = &mut server.rooms[room_id];

                    room.voting = Some(voting);

                    response.add(server_chat(msg).send_all().in_room(room_id));

                    super::common::submit_vote(

                        server,

                        types::Vote {

                            is_pro: true,

                            is_forced: false,

                        },

                        response,

                    );

                }

                Some(msg) => {

                    response.add(server_chat(msg).send_self());

                }

            }

        }

        Vote(vote) => {

            super::common::submit_vote(

                server,

                types::Vote {

                    is_pro: vote,

                    is_forced: false,

                },

                response,

            );

        }

        ForceVote(vote) => {

            let is_forced = client.is_admin();

            super::common::submit_vote(

                server,

                types::Vote {

                    is_pro: vote,

                    is_forced,

                },

                response,

            );