use std::collections::BTreeMap;
use std::convert::TryInto;

use crate::entity::account::*;
use crate::entity::character::*;
use crate::entity::gateway::{EntityGateway, GatewayError};
use crate::entity::item::*;

use std::sync::{Arc, Mutex};

#[derive(Clone)]
pub struct InMemoryGateway {
    users: Arc<Mutex<BTreeMap<UserAccountId, UserAccountEntity>>>,
    user_settings: Arc<Mutex<BTreeMap<UserSettingsId, UserSettingsEntity>>>,
    characters: Arc<Mutex<BTreeMap<CharacterEntityId, CharacterEntity>>>,
    items: Arc<Mutex<BTreeMap<ItemEntityId, ItemEntity>>>,
    mag_modifiers: Arc<Mutex<BTreeMap<ItemEntityId, Vec<mag::MagModifier>>>>,
}

impl InMemoryGateway {
    pub fn new() -> InMemoryGateway {
        InMemoryGateway {
            users: Arc::new(Mutex::new(BTreeMap::new())),
            user_settings: Arc::new(Mutex::new(BTreeMap::new())),
            characters: Arc::new(Mutex::new(BTreeMap::new())),
            items: Arc::new(Mutex::new(BTreeMap::new())),
            mag_modifiers: Arc::new(Mutex::new(BTreeMap::new())),
        }
    }
}

#[async_trait::async_trait]
impl EntityGateway for InMemoryGateway {
    async fn create_user(&mut self, user: NewUserAccountEntity) -> Result<UserAccountEntity, GatewayError> {
        let mut users = self.users.lock().unwrap();
        let id = users
            .iter()
            .fold(0, |sum, (i, _)| std::cmp::max(sum, i.0))
            + 1;
        let user = UserAccountEntity {
            id: UserAccountId(id),
            username: user.username,
            password: user.password,
            guildcard: user.guildcard,
            team_id: user.team_id,
            banned_until: user.banned_until,
            muted_until: user.muted_until,
            created_at: chrono::Utc::now(),
            flags: user.flags,
            activated: user.activated,
            at_login: false,
            at_character: false,
            at_ship: false,
        };
        users.insert(user.id, user.clone());
        Ok(user)
    }

    async fn get_user_by_id(&self, id: UserAccountId) -> Result<UserAccountEntity, GatewayError> {
        let users = self.users.lock().unwrap();
        users.get(&id).map(|k| k.clone()).ok_or(GatewayError::Error)
    }

    async fn get_user_by_name(&self, username: String) -> Result<UserAccountEntity, GatewayError> {
        let users = self.users.lock().unwrap();
        users
            .iter()
            .find(|(_, k)| k.username == username)
            .map(|(_, k)| k.clone())
            .ok_or(GatewayError::Error)
    }

    async fn save_user(&mut self, user: &UserAccountEntity) -> Result<(), GatewayError>  {
        let mut users = self.users.lock().unwrap();
        users.insert(user.id, user.clone());
        Ok(())
    }

    async fn create_user_settings(&mut self, settings: NewUserSettingsEntity) -> Result<UserSettingsEntity, GatewayError> {
        let mut user_settings = self.user_settings.lock().unwrap();
        let id = user_settings
            .iter()
            .fold(0, |sum, (i, _)| std::cmp::max(sum, i.0))
            + 1;
        let new_settings = UserSettingsEntity {
            id: UserSettingsId(id),
            user_id: settings.user_id,
            settings: settings.settings,
        };
        user_settings.insert(new_settings.id, new_settings.clone());
        Ok(new_settings)
    }

    async fn get_user_settings_by_user(&self, user: &UserAccountEntity) -> Result<UserSettingsEntity, GatewayError> {
        let user_settings = self.user_settings.lock().unwrap();
        user_settings
            .iter()
            .find(|(_, k)| k.user_id == user.id)
            .map(|(_, k)| k.clone())
            .ok_or(GatewayError::Error)
    }

    async fn get_characters_by_user(&self, user: &UserAccountEntity) -> Result<[Option<CharacterEntity>; 4], GatewayError> {
        let characters = self.characters.lock().unwrap();
        let mut chars = [None; 4];
        characters
            .iter()
            .filter(|(_, c)| c.user_id == user.id)
            .for_each(|(_, c)| chars[c.slot as usize] = Some(c.clone()));
        Ok(chars)
    }

    async fn create_character(&mut self, character: NewCharacterEntity) -> Result<CharacterEntity, GatewayError> {
        let mut characters = self.characters.lock().unwrap();
        let id = characters
            .iter()
            .fold(0, |sum, (i, _)| std::cmp::max(sum, i.0))
            + 1;

        let new_character = CharacterEntity {
            id: CharacterEntityId(id),
            user_id: character.user_id,
            slot: character.slot,
            name: character.name,
            exp: character.exp,
            char_class: character.char_class,
            section_id: character.section_id,
            appearance: character.appearance,
            techs: character.techs,
            config: character.config,
            info_board: character.info_board,
            guildcard: character.guildcard,
            materials: character.materials,
            tech_menu: character.tech_menu,
            meseta: character.meseta,
            bank_meseta: character.bank_meseta,
            option_flags: character.option_flags,
        };
        characters.insert(new_character.id, new_character.clone());
        Ok(new_character)
    }

    async fn save_character(&mut self, char: &CharacterEntity) -> Result<(), GatewayError>  {
        let mut characters = self.characters.lock().unwrap();
        characters.insert(char.id, char.clone());
        Ok(())
    }

    async fn get_guild_card_data_by_user(&self, user: &UserAccountEntity) -> Result<GuildCardDataEntity, GatewayError> {
        Ok(GuildCardDataEntity::new(user.id))
    }

    async fn create_item(&mut self, item: NewItemEntity) -> Result<ItemEntity, GatewayError> {
        let mut items = self.items.lock().unwrap();
        let id = items
            .iter()
            .fold(0, |sum, (i, _)| std::cmp::max(sum, i.0))
            + 1;
        let new_item = ItemEntity {
            id: ItemEntityId(id),
            location: item.location,
            item: item.item,
        };
        items.insert(ItemEntityId(id), new_item.clone());
        Ok(new_item)
    }

    async fn change_item(&mut self, id: &ItemEntityId, item: &ItemDetail) -> Result<(), GatewayError>  {
        let mut items = self.items.lock().unwrap();
        if let Some((_, ref mut old_item)) = items.iter_mut().find(|(existing_id, _)| **existing_id == *id) {
            old_item.item = item.clone();
        }

        Ok(())
    }

    async fn change_item_location(&mut self, item_id: &ItemEntityId, item_location: ItemLocation) -> Result<(), GatewayError> {
        self.items.lock().unwrap().get_mut(&item_id)
            .map(|item_entity| {
                item_entity.location = item_location
            });
        Ok(())
    }

    async fn feed_mag(&mut self, mag_item_id: &ItemEntityId, tool_item_id: &ItemEntityId) -> Result<(), GatewayError> {
        self.mag_modifiers.lock().unwrap()
            .entry(*mag_item_id)
            .or_insert(Vec::new())
            .push(mag::MagModifier::FeedMag {
                food: *tool_item_id
            });
        Ok(())
    }

    async fn change_mag_owner(&mut self, mag_item_id: &ItemEntityId, character: &CharacterEntity) -> Result<(), GatewayError> {
        self.mag_modifiers.lock().unwrap()
            .entry(*mag_item_id)
            .or_insert(Vec::new())
            .push(mag::MagModifier::OwnerChange(character.char_class, character.section_id));
        Ok(())
    }

    async fn use_mag_cell(&mut self, mag_item_id: &ItemEntityId, mag_cell_id: &ItemEntityId) -> Result<(), GatewayError> {
        self.mag_modifiers.lock().unwrap()
            .entry(*mag_item_id)
            .or_insert(Vec::new())
            .push(mag::MagModifier::MagCell(mag_cell_id.clone()));
        Ok(())
    }

    async fn get_items_by_character(&self, char_id: &CharacterEntityId) -> Result<Vec<ItemEntity>, GatewayError> {
        let items = self.items.lock().unwrap();
        Ok(items
            .iter()
            .filter(|(_, k)| {
                match k.location {
                    ItemLocation::Inventory{character_id, ..} => character_id == *char_id,
                    ItemLocation::Bank{character_id, ..} => character_id == *char_id,
                    _ => false
                }
            })
            .map(|(_, k)| {
                k.clone()
            })
            .map(|mut item| {
                item.item = match item.item {
                    ItemDetail::Mag(mut mag) => {
                        self.mag_modifiers.lock().unwrap().get(&item.id).map(|mag_modifiers| {
                            for mag_modifier in mag_modifiers.iter() {
                                match mag_modifier {
                                    mag::MagModifier::FeedMag {food} => {
                                        items.get(&food).map(|mag_feed| {
                                            match mag_feed.item {
                                                ItemDetail::Tool(mag_feed) => mag.feed(mag_feed.tool),
                                                _ => {}
                                            }
                                        });
                                    },
                                    mag::MagModifier::OwnerChange(class, section_id) => {
                                        mag.change_owner(*class, *section_id)
                                    },
                                    mag::MagModifier::MagCell(mag_cell_id) => {
                                        items.get(&mag_cell_id).map(|mag_cell| {
                                            match mag_cell.item {
                                                ItemDetail::Tool(mag_cell) => mag.apply_mag_cell(mag_cell.tool.try_into().unwrap()),
                                                _ => {}
                                            }
                                        });
                                    },
                                    _ => {}
                                }
                            }
                        });
                        ItemDetail::Mag(mag)
                    }
                    _ => item.item
                };
                item
            })
            .collect())
    }
}