// @flow

import Piece from "./Piece";
import ScoreManager from "./ScoreManager";
import GridManager from "./GridManager";

export default class GameLogic {

    static levelTicks = [
        1000,
        800,
        600,
        400,
        300,
        200,
        150,
        100,
    ];

    scoreManager: ScoreManager;
    gridManager: GridManager;

    height: number;
    width: number;

    gameRunning: boolean;
    gamePaused: boolean;
    gameTime: number;

    currentObject: Piece;

    gameTick: number;
    gameTickInterval: IntervalID;
    gameTimeInterval: IntervalID;

    pressInInterval: TimeoutID;
    isPressedIn: boolean;
    autoRepeatActivationDelay: number;
    autoRepeatDelay: number;

    nextPieces: Array<Piece>;
    nextPiecesCount: number;

    onTick: Function;
    onClock: Function;
    endCallback: Function;

    colors: Object;

    constructor(height: number, width: number, colors: Object) {
        this.height = height;
        this.width = width;
        this.gameRunning = false;
        this.gamePaused = false;
        this.colors = colors;
        this.autoRepeatActivationDelay = 300;
        this.autoRepeatDelay = 50;
        this.nextPieces = [];
        this.nextPiecesCount = 3;
        this.scoreManager = new ScoreManager();
        this.gridManager = new GridManager(this.getWidth(), this.getHeight(), this.colors);
    }

    getHeight(): number {
        return this.height;
    }

    getWidth(): number {
        return this.width;
    }

    getCurrentGrid() {
        return this.gridManager.getCurrentGrid();
    }

    isGameRunning(): boolean {
        return this.gameRunning;
    }

    isGamePaused(): boolean {
        return this.gamePaused;
    }

    onFreeze() {
        this.gridManager.freezeTetromino(this.currentObject, this.scoreManager);
        this.createTetromino();
    }

    setNewGameTick(level: number) {
        if (level >= GameLogic.levelTicks.length)
            return;
        this.gameTick = GameLogic.levelTicks[level];
        clearInterval(this.gameTickInterval);
        this.gameTickInterval = setInterval(this.onTick, this.gameTick);
    }

    onTick(callback: Function) {
        this.currentObject.tryMove(0, 1,
            this.gridManager.getCurrentGrid(), this.getWidth(), this.getHeight(),
            () => this.onFreeze());
        callback(
            this.scoreManager.getScore(),
            this.scoreManager.getLevel(),
            this.gridManager.getFinalGrid(this.currentObject));
        if (this.scoreManager.canLevelUp())
            this.setNewGameTick(this.scoreManager.getLevel());
    }

    onClock(callback: Function) {
        this.gameTime++;
        callback(this.gameTime);
    }

    canUseInput() {
        return this.gameRunning && !this.gamePaused
    }

    rightPressed(callback: Function) {
        this.isPressedIn = true;
        this.movePressedRepeat(true, callback, 1, 0);
    }

    leftPressedIn(callback: Function) {
        this.isPressedIn = true;
        this.movePressedRepeat(true, callback, -1, 0);
    }

    downPressedIn(callback: Function) {
        this.isPressedIn = true;
        this.movePressedRepeat(true, callback, 0, 1);
    }

    movePressedRepeat(isInitial: boolean, callback: Function, x: number, y: number) {
        if (!this.canUseInput() || !this.isPressedIn)
            return;
        const moved = this.currentObject.tryMove(x, y,
            this.gridManager.getCurrentGrid(), this.getWidth(), this.getHeight(),
            () => this.onFreeze());
        if (moved) {
            if (y === 1) {
                this.scoreManager.incrementScore();
                callback(this.gridManager.getFinalGrid(this.currentObject), this.scoreManager.getScore());
            } else
                callback(this.gridManager.getFinalGrid(this.currentObject));
        }
        this.pressInInterval = setTimeout(() => this.movePressedRepeat(false, callback, x, y), isInitial ? this.autoRepeatActivationDelay : this.autoRepeatDelay);
    }

    pressedOut() {
        this.isPressedIn = false;
        clearTimeout(this.pressInInterval);
    }

    rotatePressed(callback: Function) {
        if (!this.canUseInput())
            return;

        if (this.currentObject.tryRotate(this.gridManager.getCurrentGrid(), this.getWidth(), this.getHeight()))
            callback(this.gridManager.getFinalGrid(this.currentObject));
    }

    getNextPiecesPreviews() {
        let finalArray = [];
        for (let i = 0; i < this.nextPieces.length; i++) {
            finalArray.push(this.gridManager.getEmptyGrid(4, 4));
            this.nextPieces[i].toGrid(finalArray[i], true);
        }

        return finalArray;
    }

    recoverNextPiece() {
        this.currentObject = this.nextPieces.shift();
        this.generateNextPieces();
    }

    generateNextPieces() {
        while (this.nextPieces.length < this.nextPiecesCount) {
            this.nextPieces.push(new Piece(this.colors));
        }
    }

    createTetromino() {
        this.pressedOut();
        this.recoverNextPiece();
        if (!this.currentObject.isPositionValid(this.gridManager.getCurrentGrid(), this.getWidth(), this.getHeight()))
            this.endGame(false);
    }

    togglePause() {
        if (!this.gameRunning)
            return;
        this.gamePaused = !this.gamePaused;
        if (this.gamePaused) {
            clearInterval(this.gameTickInterval);
            clearInterval(this.gameTimeInterval);
        } else {
            this.gameTickInterval = setInterval(this.onTick, this.gameTick);
            this.gameTimeInterval = setInterval(this.onClock, 1000);
        }
    }

    endGame(isRestart: boolean) {
        this.gameRunning = false;
        this.gamePaused = false;
        clearInterval(this.gameTickInterval);
        clearInterval(this.gameTimeInterval);
        this.endCallback(this.gameTime, this.scoreManager.getScore(), isRestart);
    }

    startGame(tickCallback: Function, clockCallback: Function, endCallback: Function) {
        if (this.gameRunning)
            this.endGame(true);
        this.gameRunning = true;
        this.gamePaused = false;
        this.gameTime = 0;
        this.scoreManager = new ScoreManager();
        this.gameTick = GameLogic.levelTicks[this.scoreManager.getLevel()];
        this.gridManager = new GridManager(this.getWidth(), this.getHeight(), this.colors);
        this.nextPieces = [];
        this.generateNextPieces();
        this.createTetromino();
        tickCallback(
            this.scoreManager.getScore(),
            this.scoreManager.getLevel(),
            this.gridManager.getFinalGrid(this.currentObject));
        clockCallback(this.gameTime);
        this.onTick = this.onTick.bind(this, tickCallback);
        this.onClock = this.onClock.bind(this, clockCallback);
        this.gameTickInterval = setInterval(this.onTick, this.gameTick);
        this.gameTimeInterval = setInterval(this.onClock, 1000);
        this.endCallback = endCallback;
    }
}