const express = require('express'),
    router = express.Router(),
    mdEmoji = require('markdown-it-emoji'),
    mdMark = require('markdown-it-mark'),
    mdSmartarrows = require('markdown-it-smartarrows'),
    md = require('markdown-it')()
        .use(mdEmoji)
        .use(mdMark)
        .use(mdSmartarrows),
    utils = require('../lib/utils'),
    globals = require('../lib/globals');

let pgPool = globals.pgPool;
let bingoSessions = {};

/**
 * Class to manage the bingo data in the database.
 */
class BingoDataManager {
    /**
     * constructor functino
     * @param postgresPool {pg.Pool} - the postgres pool
     */
    constructor(postgresPool) {
        this.pgPool = postgresPool;
        this.queries = utils.parseSqlYaml('./sql/bingo');
    }

    async init() {
        await this.pgPool.query(this.queries.createTables.sql);
        setInterval(async () => await this._databaseCleanup(), 5*60*1000);  // database cleanup every 5 minutes
    }

    /**
     * Try-catch wrapper around the pgPool.query.
     * @param query {String} - the sql query
     * @param [values] {Array} - an array of values
     * @returns {Promise<*>}
     */
    async _queryDatabase(query, values) {
        try {
            return await this.pgPool.query(query, values);
        } catch (err) {
            console.error(`Error on query "${query}" with values ${JSON.stringify(values)}.`);
            console.error(err);
            console.error(err.stack);
            return {
                rows: null
            };
        }
    }

    /**
     * Queries the database and returns all resulting rows
     * @param query {String} - the sql query
     * @param values {Array} - an array of parameters needed in the query
     * @returns {Promise<*>}
     * @private
     */
    async _queryAllResults(query, values) {
        let result = await this._queryDatabase(query, values);
        return result.rows || [];
    }

    /**
     * Query the database and return the first result or null
     * @param query {String} - the sql query
     * @param values {Array} - an array of parameters needed in the query
     * @returns {Promise<*>}
     */
    async _queryFirstResult(query, values) {
        let result = await this._queryDatabase(query, values);
        if (result.rows && result.rows.length > 0)
            return result.rows[0];
    }

    /**
     * Clears expired values from the database.
     */
    async _databaseCleanup() {
        await this._queryDatabase(this.queries.cleanup.sql);
    }

    /**
     * Add a player to the players table
     * @param username {String} - the username of the player
     * @returns {Promise<*>}
     */
    async addPlayer(username) {
        let result = await this._queryFirstResult(this.queries.addPlayer.sql, [username]);
        if (result)
            return result;
        else
            return {};  // makes things easier
    }

    /**
     * Updates the username of a player
     * @param playerId {Number} - the id of the player
     * @param username {String} - the new username
     * @returns {Promise<void>}
     */
    async updatePlayerUsername(playerId, username) {
        return await this._queryFirstResult(this.queries.updatePlayerUsername.sql, [username, playerId]);
    }

    /**
     * Returns the username for a player-id
     * @param playerId {Number} - the id of the player
     * @returns {Promise<*>}
     */
    async getPlayerInfo(playerId) {
        return await this._queryFirstResult(this.queries.getPlayerInfo.sql, [playerId]);
    }

    /**
     * Updates the expiration date of a player
     * @param playerId {Request} - thie id of the player
     * @returns {Promise<void>}
     */
    async updatePlayerExpiration(playerId) {
        await this._queryDatabase(this.queries.updatePlayerExpire.sql, [playerId]);
    }

    /**
     * Creates a bingo lobby.
     * @param playerId
     * @param gridSize
     * @returns {Promise<*>}
     */
    async createLobby(playerId, gridSize) {
        return await this._queryFirstResult(this.queries.addLobby.sql, [playerId, gridSize]);
    }

    /**
     * Updates the expiration date of a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<*>}
     */
    async updateLobbyExpiration(lobbyId) {
        return await this._queryDatabase(this.queries.updateLobbyExpire.sql, [lobbyId]);
    }

    /**
     * Returns the row of the lobby.
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<*>}
     */
    async getLobbyInfo(lobbyId) {
        return await this._queryFirstResult(this.queries.getLobbyInfo.sql, [lobbyId]);
    }

    /**
     * Checks if a player is in a lobby.
     * @param playerId {Number} - the id of the player
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<*>}
     */
    async getPlayerInLobby(playerId, lobbyId) {
        return (await this._queryFirstResult(this.queries.getPlayerInLobby.sql, [playerId, lobbyId]));
    }

    /**
     * Returns all players in a lobby.
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<*>}
     */
    async getLobbyPlayers(lobbyId) {
        return await this._queryAllResults(this.queries.getLobbyPlayers.sql, [lobbyId]);
    }

    /**
     * Returns the last messages in a lobby with a limit
     * @param lobbyId {Number} - the id of the lobby
     * @param [limit] {Number} - the maximum of messages to fetch
     * @returns {Promise<*>}
     */
    async getLobbyMessages(lobbyId, limit=20) {
        return await this._queryAllResults(this.queries.getLobbyMessages.sql, [lobbyId, limit]);
    }

    /**
     * Adds a player to a lobby.
     * @param playerId {Number} - the id of the player
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<*>}
     */
    async addPlayerToLobby(playerId, lobbyId) {
        let entry = await this.getPlayerInLobby(playerId, lobbyId);
        if (entry) {
            entry.lobby_id = entry.id;
            return entry;
        } else {
            return await this._queryFirstResult(this.queries.addPlayerToLobby.sql, [playerId, lobbyId]);
        }
    }

    /**
     * Sets the current round property of the lobby
     * @param lobbyId {Number} - the id of the lobby
     * @param roundId {Number} - the id of the round
     * @returns {Promise<*>}
     */
    async setLobbyCurrentRound(lobbyId, roundId) {
        return await this._queryFirstResult(this.queries.setLobbyCurrentRound.sql, [lobbyId, roundId]);
    }

    /**
     * Updates the grid size of a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @param gridSize {Number} - the new grid size
     * @returns {Promise<*>}
     */
    async setLobbyGridSize(lobbyId, gridSize) {
        return await this._queryFirstResult(this.queries.setLobbyGridSize.sql, [lobbyId, gridSize]);
    }

    /**
     * Removes a player from a lobbby
     * @param playerId {Number} - the id of the player
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<*>}
     */
    async removePlayerFromLobby(playerId, lobbyId) {
        return await this._queryFirstResult(this.queries.removePlayerFromLobby.sql, [playerId, lobbyId]);
    }

    /**
     * Adds a word to a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @param word {Number} - the id of the word
     * @returns {Promise<void>}
     */
    async addWordToLobby(lobbyId, word) {
        return await this._queryFirstResult(this.queries.addWord.sql, [lobbyId, word]);
    }

    /**
     * Returns all words used in a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<void>}
     */
    async getWordsForLobby(lobbyId) {
        return await this._queryAllResults(this.queries.getWordsForLobby.sql, [lobbyId]);
    }

    /**
     * Returns information about a word
     * @param wordId {Number} - the id of the word
     * @returns {Promise<*>}
     */
    async getWordInfo(wordId) {
        return await this._queryFirstResult(this.queries.getWordInfo.sql, [wordId]);
    }

    /**
     * Returns all rounds of a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<*>}
     */
    async getLobbyRounds(lobbyId) {
        return await this._queryAllResults(this.queries.getLobbyRounds.sql, [lobbyId]);
    }

    /**
     * Returns the round row of a round
     * @param roundId {Number} - the id of the round
     * @returns {Promise<*>}
     */
    async getRoundInfo(roundId) {
        return await this._queryFirstResult(this.queries.getRoundInfo.sql, [roundId]);
    }

    /**
     * Updates the status of a round
     * @param roundId {Number} - the id of the round
     * @param status {String<8>} - the new status
     * @returns {Promise<*>}
     */
    async updateRoundStatus(roundId, status) {
        return await this._queryFirstResult(this.queries.updateRoundStatus.sql, [roundId, status]);
    }

    /**
     * Returns the number of wins the player had in a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @param playerId {Number} - the id of the player
     * @returns {Promise<*>}
     */
    async getLobbyPlayerWins(lobbyId, playerId) {
        return await this._queryFirstResult(this.queries.getLobbyPlayerWins.sql, [lobbyId, playerId]);
    }

    /**
     * Adds a grid for a user to a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @param playerId {Number} - the id of the user
     * @param roundId {Number} - the id of the round
     * @returns {Promise<*>}
     */
    async addGrid(lobbyId, playerId, roundId) {
        return await this._queryFirstResult(this.queries.addGrid.sql, [playerId, lobbyId, roundId]);
    }

    /**
     * Adds a word to a grid with specific location
     * @param gridId {Number} - the id of the gird
     * @param wordId {Number} - the id of the word
     * @param row {Number} - the number of the row
     * @param column {Number} - the number of the column
     */
    async addWordToGrid(gridId, wordId, row, column) {
        return await this._queryFirstResult(this.queries.addWordToGrid.sql, [gridId, wordId, row, column]);
    }

    /**
     * Returns all words in the grid with location
     * @param gridId {Number} - the id of the grid
     * @returns {Promise<*>}
     */
    async getWordsInGrid(gridId) {
        return await this._queryAllResults(this.queries.getWordsForGridId.sql, [gridId]);
    }

    /**
     * Returns the grid row for a player and lobby id
     * @param lobbyId {Number} - the id of the lobby
     * @param playerId {Number} - the id of the player
     * @param roundId {Number} - the id of the round
     * @returns {Promise<*>}
     */
    async getGridForPlayerLobbyRound(lobbyId, playerId, roundId) {
        return await this._queryFirstResult(this.queries.getGridByPlayerLobbyRound.sql, [playerId, lobbyId, roundId]);
    }

    /**
     * Returns the grid row for a grid id
     * @param gridId {Number} - the id of the grid
     * @returns {Promise<*>}
     */
    async getGridInfo(gridId) {
        return await this._queryFirstResult(this.queries.getGridInfo.sql, [gridId]);
    }

    /**
     * Sets a field of the grid to submitted/unsubmitted depending on the previous value
     * @param gridId {Number} - the id of the grid
     * @param fieldRow {Number} - the row of the field
     * @param fieldColumn {Number} - the column of the field
     * @returns {Promise<*>}
     */
    async toggleGridFieldSubmitted(gridId, fieldRow, fieldColumn) {
        return await this._queryFirstResult(this.queries.toggleGridFieldSubmitted.sql, [gridId, fieldRow, fieldColumn]);
    }

    /**
     * Adds a round for a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<*>}
     */
    async addRound(lobbyId) {
        return await this._queryFirstResult(this.queries.addRound.sql, [lobbyId]);
    }

    /**
     * Updates a round to the "FINISHED" status and sets the finish time
     * @param roundId {Number}
     * @returns {Promise<*>}
     */
    async setRoundFinished(roundId) {
        return await this._queryFirstResult(this.queries.setRoundFinished.sql, [roundId]);
    }

    /**
     * Updates the rounds winner
     * @param winnerId {Number} - the id of the winner
     * @returns {Promise<*>}
     */
    async setRoundWinner(winnerId) {
        return await this._queryFirstResult(this.queries.setRoundWiner.sql, [winnerId]);
    }

    /**
     * Inserts a message of type "USER" into the database
     * @param lobbyId {Number} - the id of the lobby
     * @param playerId {Number} - the id of the author (player)
     * @param messageContent {String} - the content of the message
     * @returns {Promise<*>}
     */
    async addUserMessage(lobbyId, playerId, messageContent) {
        return await this._queryFirstResult(this.queries.addUserMessage.sql, [playerId, lobbyId, messageContent]);
    }

    /**
     * Removes all words of a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<*>}
     */
    async clearLobbyWords(lobbyId) {
        return await this._queryFirstResult(this.queries.clearLobbyWords.sql, [lobbyId]);
    }

    /**
     * Returns a single entry from grid_words
     * @param gridId {Number} - the id of the grid
     * @param row {Number} - the row of the field
     * @param column {Number} - the column of the row
     * @returns {Promise<*>}
     */
    async getGridField(gridId, row, column) {
        return await this._queryFirstResult(this.queries.getGriedField.sql, [gridId, row, column]);
    }
}

class WordWrapper {
    /**
     * constructor
     * @param id {Number} - the id of the word
     * @param [row] {Object} - the database row of the word
     */
    constructor(id, row) {
        this.id = id;
        this._infoLoaded = false;
        if (row)
            this._assignProperties(row);
    }

    /**
     * Loads the word information from the database
     * @returns {Promise<void>}
     * @private
     */
    async _loadWordInfo() {
        if (!this._infoLoaded) {
            let row = await bdm.getWordInfo(this.id);
            if (row)
                this._assignProperties(row);
        }
    }

    /**
     * Assign the row as properties
     * @param row {Object} - the word row
     * @private
     */
    _assignProperties(row) {
        this._content = row.content;
        this._heared = row.heared;
        this._lobbyId = row.lobbyId;
        this._infoLoaded = this._content && this._heared && this._lobbyId;
    }

    /**
     * Returns a new lobby wrapper for the words lobby
     * @returns {Promise<LobbyWrapper>}
     */
    async lobby() {
        await this._loadWordInfo();
        return new LobbyWrapper(this._lobbyId);
    }

    /**
     * Returns the word iteself
     * @returns {Promise<Object.content|*>}
     */
    async content() {
        await this._loadWordInfo();
        return this._content;
    }

    /**
     * Returns the number of people that heared the word
     * @returns {Promise<Object.heared|(function())>}
     */
    async heared() {
        await  this._loadWordInfo();
        return this._heared;
    }

    /**
     * Returns if the word was confirmed heared
     * @returns {Promise<boolean>}
     */
    async confirmed() {
        await this._loadWordInfo();
        return true; // TODO confirmation logic
    }
}

class GridFieldWrapper {
    /**
     * constructor
     * @param row {Object} - the resulting row
     */
    constructor(row) {
        this.row = row.grid_row;
        this.column = row.grid_column;
        this.submitted = row.submitted;
        this.word = new WordWrapper(row.word_id, row);
        this.grid = new GridWrapper(row.grid_id);
    }
}

class GridWrapper {
    constructor(id) {
        this.id = id;
        this._infoLoaded = false;
    }

    /**
     * Loads all direct grid information
     * @returns {Promise<void>}
     * @private
     */
    async _loadGridInfo() {
        if (!this._infoLoaded) {
            let result = await bdm.getGridInfo(this.id);
            if (result) {
                this.playerId = result.player_id;
                this.lobbyId = result.lobby_id;
                this.size = result.grid_size;
            }
        }
    }

    /**
     * Gets a matrix of the submitted-values of each grid field
     * @returns {Promise<Array[[boolean]]>}
     * @private
     */
    async _getSubmittedMatrix() {
        await this._loadGridInfo();
        let rows = await bdm.getWordsInGrid(this.id);
        let matrix = [];
        for (let i = 0; i < this.size; i++) {
            matrix[i] = [];
            for (let j = 0; j < this.size; j++)
                matrix[i][j] = rows.find(x => (x.grid_row === i && x.grid_column === j)).submitted;
        }
        return matrix;
    }

    /**
     * Returns all fields in the grid
     * @returns {Promise<Array>}
     */
    async fields() {
        let rows = await bdm.getWordsInGrid(this.id);
        let fields = [];
        for (let row of rows)
            fields.push(new GridFieldWrapper(row));
        return fields;
    }

    /**
     * Returns a field with the current row and column
     * @param row {Number} - the fields row
     * @param column {Number} - the fields column
     * @returns {Promise<GridFieldWrapper>}
     */
    async field({row, column}) {
        let result = await bdm.getGridField(this.id, row, column);
        return new GridFieldWrapper(result);
    }

    /**
     * Returns if a bingo is possible
     * @returns {Promise<boolean>}
     */
    async bingo() {
        let subMatrix = await this._getSubmittedMatrix();
        return checkBingo(subMatrix);
    }

    /**
     * Returns the lobby of the grid
     * @returns {Promise<LobbyWrapper>}
     */
    async lobby() {
        await this._loadGridInfo();
        return new LobbyWrapper(this.lobbyId);
    }

    /**
     * Returns the player of the grid
     * @returns {Promise<PlayerWrapper>}
     */
    async player() {
        await this._loadGridInfo();
        return new PlayerWrapper(this.playerId);
    }

    /**
     * Toggles submitted of a grid field
     * @param row {Number} - the row of the field
     * @param column {Number} - the column of the field
     * @returns {Promise<GridFieldWrapper>}
     */
    async toggleField(row, column) {
        let result = await bdm.toggleGridFieldSubmitted(this.id, row, column);
        return new GridFieldWrapper(result);
    }
}

class MessageWrapper {
    /**
     * constructor
     * @param row {Object} - the database row of the message
     */
    constructor(row) {
        this.id = row.id;
        this.content = row.content;
        this.htmlContent = md.renderInline(this.content);
        this.author = new PlayerWrapper(row.player_id);
        this.lobby = new LobbyWrapper(row.lobby_id);
        this.type = row.type;
        this.created = row.created;
    }
}

class PlayerWrapper {
    /**
     * constructor
     * @param id {Number} - the id of the player
     */
    constructor(id) {
        this.id = id;
        this._infoLoaded = false;
    }

    /**
     * Loads all player information
     * @returns {Promise<void>}
     * @private
     */
    async _loadPlayerInfo() {
        if (!this._infoLoaded) {
            let result = await bdm.getPlayerInfo(this.id);
            if (result) {
                this._uname = result.username;
                this.expire = result.expire;
                this._infoLoaded = true;
            }
        }
    }

    /**
     * Returns the grid for a specific lobby
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<GridWrapper>}
     */
    async grid({lobbyId}) {
        let currentRound = (await new LobbyWrapper(lobbyId).currentRound()).id;
        let result = await bdm.getGridForPlayerLobbyRound(lobbyId, this.id, currentRound);
        if (result)
            return new GridWrapper(result.id);
    }

    /**
     * Returns the username of the player
     * @returns {Promise<String|null>}
     */
    async username() {
        await this._loadPlayerInfo();
        return this._uname;
    }

    /**
     * Returns the number of wins of a player in a lobby
     * @param lobbyId {Number} - the id of the lobby
     * @returns {Promise<null|PlayerWrapper.wins>}
     */
    async wins({lobbyId}) {
        let result = await bdm.getLobbyPlayerWins(lobbyId, this.id);
        if (result && result.wins)
            return result.wins;
        else
            return null;
    }
}

class RoundWrapper {
    /**
     * constructor
     * @param id {Number} - the id of the round
     * @param [row] {Object} - already queried row of the row
     */
    constructor(id, row) {
        this.id = id;
        this._infoLoaded = false;
        if (row)
            this._assignProperties(row);
    }

    /**
     * Adds data to the round wrapper
     * @param row
     * @private
     */
    _assignProperties(row) {
        this._start = row.start;
        this._finish = row.finish;
        this._status = row.status;
        this._lobbyId = row.lobby_id;
        this._winnerId = row.winner;
        this._infoLoaded = true;
    }

    /**
     * Loads the round info from the database
     * @returns {Promise<void>}
     * @private
     */
    async _loadRoundInfo() {
        if (!this._infoLoaded) {
            let row = await bdm.getRoundInfo(this.id);
            if (row)
                this._assignProperties(row);
        }
    }

    /**
     * Returns the winner of the bingo round (if exists)
     * @returns {Promise<PlayerWrapper>}
     */
    async winner() {
        await this._loadRoundInfo();
        if (this._winnerId)
            return new PlayerWrapper(this._winnerId);
    }

    /**
     * Returns the start timestamp of the round
     * @returns {Promise<String>}
     */
    async start() {
        await this._loadRoundInfo();
        return this._start;
    }

    /**
     * Returns the finish timestamp of the round if it exists
     * @returns {Promise<String|null>}
     */
    async finish() {
        await this._loadRoundInfo();
        return this._finish;
    }

    /**
     * Returns the status of a round
     * @returns {Promise<String>}
     */
    async status() {
        await this._loadRoundInfo();
        return this._status;
    }

    /**
     * Returns the lobby the round is belonging to
     * @returns {Promise<LobbyWrapper>}
     */
    async lobby() {
        await this._loadRoundInfo();
        return new LobbyWrapper(this._lobbyId);
    }

    /**
     * Updates the status of the round to a new one
     * @param status {String<8>} - the new status
     * @returns {Promise<void>}
     */
    async updateStatus(status) {
        let updateResult = await bdm.updateRoundStatus(this.id, status);
        if (updateResult)
            this._assignProperties(updateResult);
    }

    /**
     * Sets the round to finished
     * @returns {Promise<void>}
     */
    async setFinished() {
        let updateResult = await bdm.setRoundFinished(this.id);
        if (updateResult)
            this._assignProperties(updateResult);
    }

    /**
     * Sets the winner of the round
     * @param winnerId {Number} - the id of the winner
     */
    async setWinner(winnerId) {
        let status = await this.status();
        if (status !== "FINISHED") {
            let updateResult = await bdm.setRoundWinner(winnerId);
            if (updateResult)
                await this.setFinished();
            return true;
        }
    }
}

class LobbyWrapper {
    /**
     * constructor
     * @param id {Number} - the id of the lobby
     * @param [row] {Object} - the optional row object of the lobby to load info from
     */
    constructor(id, row) {
        this.id = id;
        this._infoLoaded = false;
        if (row)
            this._assignProperties(row);
    }

    /**
     * Loads information about the lobby if it hasn't been loaded yet
     * @returns {Promise<void>}
     * @private
     */
    async _loadLobbyInfo() {
        if (!this._infoLoaded) {
            let row = await bdm.getLobbyInfo(this.id);
            this._assignProperties(row);
        }
    }

    /**
     * Assigns properties to the lobby wrapper
     * @param row {Object} - the row to assign properties from
     * @private
     */
    _assignProperties(row) {
        if (row) {
            this.admin_id = row.admin_id;
            this.grid_size = row.grid_size;
            this.expire = row.expire;
            this.current_round = row.current_round;
            this._infoLoaded = true;
        }
    }

    /**
     * returns the players in the lobby
     * @returns {Promise<Array>}
     */
    async players() {
        let rows = await bdm.getLobbyPlayers(this.id);
        let players = [];
        for (let row of rows)
            players.push(new PlayerWrapper(row.player_id));
        return players;
    }

    /**
     * Returns the admin of the lobby
     * @returns {Promise<PlayerWrapper>}
     */
    async admin() {
        await this._loadLobbyInfo();
        return new PlayerWrapper(this.admin_id);
    }

    /**
     * Returns the active round of the lobby
     * @returns {Promise<RoundWrapper>}
     */
    async currentRound() {
        await this._loadLobbyInfo();
        if (this.current_round)
            return new RoundWrapper(this.current_round);
    }

    /**
     * Returns all round of a lobby
     * @returns {Promise<Array>}
     */
    async rounds() {
        let rows = await bdm.getLobbyRounds(this.id);
        let rounds = [];
        for (let row of rows)
            rounds.push(new RoundWrapper(row.id, row));
        return rounds;
    }

    /**
     * Returns the grid-size of the lobby
     * @returns {Promise<void>}
     */
    async gridSize() {
        await this._loadLobbyInfo();
        return this.grid_size;
    }

    /**
     * Returns a number of messages send in the lobby
     * @param limit
     * @returns {Promise<Array>}
     */
    async messages({limit}) {
        let rows = await bdm.getLobbyMessages(this.id, limit);
        let messages = [];
        for (let row of rows)
            messages.push(new MessageWrapper(row));
        return messages;
    }

    /**
     * Returns all words in a lobby
     * @returns {Promise<Array>}
     */
    async words() {
        let rows = await bdm.getWordsForLobby(this.id);
        let words = [];
        for (let row of rows)
            words.push(new WordWrapper(row.id, row));
        return words;
    }

    /**
     * Creates a new round
     * @returns {Promise<*>}
     */
    async _createRound() {
        let result = await bdm.addRound(this.id);
        if (result && result.id) {
            let updateResult = await bdm.setLobbyCurrentRound(this.id, result.id);
            this._assignProperties(updateResult);
            return result.id;
        }
    }

    /**
     * Creates a grid for each player
     * @returns {Promise<void>}
     */
    async _createGrids() {
        let words = await this.words();
        let players = await this.players();
        let currentRound = this.current_round;
        for (let player of players) {
            // eslint-disable-next-line no-await-in-loop
            let gridId = (await bdm.addGrid(this.id, player.id, currentRound)).id;
            let gridContent = generateWordGrid(this.grid_size, words);

            for (let i = 0; i < gridContent.length; i++)
                for (let j = 0; j < gridContent[i].length; j++)
                    // eslint-disable-next-line no-await-in-loop
                    await bdm.addWordToGrid(gridId, gridContent[i][j].id, i, j);
        }
    }

    /**
     * Creates a new round and new grids for each player
     * @returns {Promise<void>}
     */
    async startNewRound() {
        let words = await this.words();
        if (words && words.length > 0) {
            let currentRound = await this.currentRound();
            if (currentRound)
                await currentRound.setFinished();
            await this._createRound();
            await this._createGrids();
        }
    }

    /**
     * Sets the grid size of the lobby
     * @param gridSize {Number} - the new grid size
     * @returns {Promise<void>}
     */
    async setGridSize(gridSize) {
        let updateResult = await bdm.setLobbyGridSize(this.id, gridSize);
        this._assignProperties(updateResult);
    }

    /**
     * Returns if the specific player exists in the lobby
     * @param playerId
     * @returns {Promise<*>}
     */
    async hasPlayer(playerId) {
        let result = (await bdm.getPlayerInLobby(playerId, this.id));
        return (result && result.player_id);
    }

    /**
     * Sets the words of the lobby
     * @param words
     * @returns {Promise<void>}
     */
    async setWords(words) {
        if (words.length > 0) {
            await bdm.clearLobbyWords(this.id);
            for (let word of words)
                // eslint-disable-next-line no-await-in-loop
                await bdm.addWordToLobby(this.id, word);
        }
    }
}


/**
 * Replaces tag signs with html-escaped signs.
 * @param htmlString
 * @returns {string}
 */
function replaceTagSigns(htmlString) {
    return htmlString.replace(/</g, '&#60;').replace(/>/g, '&#62;');
}

/**
 * Shuffles the elements in an array
 * @param array  {Array<*>}
 * @returns {Array<*>}
 */
function shuffleArray(array) {
    let counter = array.length;
    while (counter > 0) {
        let index = Math.floor(Math.random() * counter);
        counter--;
        let temp = array[counter];
        array[counter] = array[index];
        array[index] = temp;
    }
    return array;
}

/**
 * Inflates an array to a minimum Size
 * @param array {Array} - the array to inflate
 * @param minSize {Number} - the minimum size that the array needs to have
 * @returns {Array}
 */
function inflateArray(array, minSize) {
    let resultArray = array;
    let iterations = Math.ceil(minSize/array.length)-1;
    for (let i = 0; i < iterations; i++)
        resultArray = [...resultArray, ...resultArray];
    return resultArray;
}

/**
 * Generates a word grid with random word placements in the given dimensions
 * @param size {Array<Number>} - the dimensions of the grid
 * @param words {Array<*>} - the words included in the grid
 * @returns {Array}
 */
function generateWordGrid(size, words) {
    let shuffledWords = shuffleArray(inflateArray(words, size**2));
    let grid = [];
    for (let x = 0; x < size; x++) {
        grid[x] = [];
        for (let y = 0; y < size; y++)
            grid[x][y] = shuffledWords[(x * size) + y];
    }
    return grid;
}

/**
 * Checks if a diagonal bingo is possible
 * @param fg {Array<Array<boolean>>} - the grid with the checked (submitted) values
 * @returns {boolean|boolean|*}
 */
function checkBingoDiagnoal(fg) {
    let bingoCheck = true;
    // diagonal check
    for (let i = 0; i < fg.length; i++)
        bingoCheck = fg[i][i] && bingoCheck;
    if (bingoCheck)
        return true;
    bingoCheck = true;
    for (let i = 0; i < fg.length; i++)
        bingoCheck = fg[i][fg.length - i - 1] && bingoCheck;
    return bingoCheck;
}

/**
 * Checks if a vertical bingo is possible
 * @param fg {Array<Array<boolean>>} - the grid with the checked (submitted) values
 * @returns {boolean|boolean|*}
 */
function checkBingoVertical(fg) {
    let bingoCheck = true;
    for (let row of fg) {
        bingoCheck = true;
        for (let field of row)
            bingoCheck = field && bingoCheck;
        if (bingoCheck)
            return true;
    }
    return bingoCheck;
}

/**
 * Checks if a horizontal bingo is possible
 * @param fg {Array<Array<boolean>>} - the grid with the checked (submitted) values
 * @returns {boolean|boolean|*}
 */
function checkBingoHorizontal(fg) {
    let bingoCheck = true;
    // vertical check
    for (let i = 0; i < fg.length; i++) {
        bingoCheck = true;
        for (let j = 0; j < fg.length; j++)
            bingoCheck = fg[j][i] && bingoCheck;
        if (bingoCheck)
            return true;
    }
    return bingoCheck;
}

/**
 * Checks if a bingo exists in the bingo grid.
 * @param fg {Array<[Boolean]>}
 * @returns {boolean}
 */
function checkBingo(fg) {
    let diagonalBingo = checkBingoDiagnoal(fg);
    let verticalCheck = checkBingoVertical(fg);
    let horizontalCheck = checkBingoHorizontal(fg);
    return diagonalBingo || verticalCheck || horizontalCheck;
}


// -- Router stuff


let bdm = new BingoDataManager(pgPool);

router.init = async () => {
    await bdm.init();
};

router.use(async (req, res, next) => {
    if (req.session.bingoPlayerId)
        await bdm.updatePlayerExpiration(req.session.bingoPlayerId);
    next();
});

router.get('/', (req, res) => {
    let bingoUser = req.session.bingoUser;
    if (req.query.game) {
        let gameId = req.query.game || bingoUser.game;

        if (bingoSessions[gameId] && !bingoSessions[gameId].finished) {
            bingoUser.game = gameId;
            let bingoSession = bingoSessions[gameId];
            if (!bingoSession.users[bingoUser.id])
                bingoSession.addUser(bingoUser);

            if (!bingoUser.grids[gameId])
                bingoUser.grids[gameId] = generateWordGrid(bingoSession.gridSize, bingoSession.words);

            res.render('bingo/bingo-game', {
                grid: bingoUser.grids[gameId].fieldGrid,
                username: bingoUser.username,
                players: bingoSession.players()
            });
        } else {
            res.render('bingo/bingo-submit');
        }
    } else {
        res.render('bingo/bingo-submit');
    }
});

router.graphqlResolver = async (req, res) => {
    let playerId = req.session.bingoPlayerId;
    if (playerId)
        await bdm.updatePlayerExpiration(playerId);

    return {
        // queries
        lobby: ({id}) => {
            return new LobbyWrapper(id);
        },
        player: ({id}) => {
            if (id)
                return new PlayerWrapper(id);
            else
                if (playerId)
                    return new PlayerWrapper(playerId);
                else
                    res.status(400);
        },
        // mutations
        setUsername: async ({username}) => {
            username = username.substring(0, 30); // only allow 30 characters

            if (!playerId) {
                req.session.bingoPlayerId = (await bdm.addPlayer(username)).id;
                playerId = req.session.bingoPlayerId;
            } else {
                await bdm.updatePlayerUsername(playerId, username);
            }
            return new PlayerWrapper(playerId);
        },
        createLobby: async({gridSize}) => {
            if (playerId) {
                let result = await bdm.createLobby(playerId, gridSize);
                return new LobbyWrapper(result.id);
            } else {
                res.status(400);
            }
        },
        mutateLobby: async ({id}) => {
            let lobbyId = id;
            await bdm.updateLobbyExpiration(lobbyId);
            let lobbyWrapper = new LobbyWrapper(lobbyId);
            return {
                join: async () => {
                    if (playerId) {
                        let result = await bdm.addPlayerToLobby(playerId, lobbyId);
                        return new LobbyWrapper(result.lobby_id);
                    } else {
                        res.status(400);
                    }
                },
                leave: async () => {
                    if (playerId) {
                        await bdm.removePlayerFromLobby(playerId, lobbyId);
                        return true;
                    } else {
                        res.status(400);
                    }
                },
                kickPlayer: async ({pid}) => {
                    let result = await bdm.removePlayerFromLobby(pid, lobbyId);
                    return new LobbyWrapper(result.id, result);
                },
                startRound: async () => {
                    await lobbyWrapper.startNewRound();
                    return lobbyWrapper.currentRound();
                },
                setGridSize: async ({gridSize}) => {
                    await lobbyWrapper.setGridSize(gridSize);
                    return lobbyWrapper;
                },
                setWords: async({words}) => {
                    let admin = await lobbyWrapper.admin();
                    if (admin.id === playerId) {
                        await lobbyWrapper.setWords(words);
                        return lobbyWrapper;
                    } else {
                        res.status(400);
                    }
                },
                sendMessage: async ({message}) => {
                    if (await lobbyWrapper.hasPlayer(playerId)) {
                        let result = await bdm.addUserMessage(lobbyId, playerId, message);
                        return new MessageWrapper(result);
                    } else {
                        res.status(400);
                    }
                },
                submitBingo: async () => {
                    let isBingo = await (await (new PlayerWrapper(playerId)).grid({lobbyId: lobbyId})).bingo();
                    let currentRound = await lobbyWrapper.currentRound();
                    if (isBingo) {
                        let result = await currentRound.setWinner(playerId);
                        if (result)
                            return currentRound;
                        else
                            res.status(400);
                    } else {
                        res.status(400);
                    }
                },
                toggleGridField: async ({location}) => {
                    let {row, column} = location;
                    return await (await (new PlayerWrapper(playerId)).grid({lobbyId: lobbyId}))
                        .toggleField(row, column);
                }
            };
        }
    };
};

module.exports = router;