const chalk = require('chalk')


var cursorX = 0;
var cursorY = 0;

var placing = getRandomBlock(false);

var board = [];
var score = 0;
for (var y = 0; y < 7; y++) {
    board.push([]);
    for (var x = 0; x < 7; x++) {
        board[y].push(0);
    }
}

const blocksToPlace = 25;
const solidRows = 3;
for (var i = 0;i < solidRows;i++){
    for (var x = 0; x < 7; x++) {
        dropBlock(-2, x);

    }
}
for (var i = 0; i < blocksToPlace; i++) {
    dropBlock(getRandomBlock(true), Math.floor(Math.random() * 7));
}


const readline = require('readline');
readline.emitKeypressEvents(process.stdin);
process.stdin.setRawMode(true);
process.stdin.on('keypress', (str, key) => {
    if (key.ctrl && key.name === 'c') {
        process.exit();
        
    } else {
        switch (key.name) {
            case 'left':
                cursorX = Math.max(0, cursorX - 1);
                break;
            case 'right':
                cursorX = Math.min(6, cursorX + 1);
                break;
            case 'up':
                cursorY = Math.max(0, cursorY - 1);
                break;
            case 'down':
                cursorY = Math.min(6, cursorY + 1);
                break;
            case 'enter':
            case 'return':
                const successfullyDropped = dropBlock(placing, cursorX);
                if(successfullyDropped)
                    placing = getRandomBlock(false);

        }
        paintBoard();

    }
});
console.log('Press any key...');

function getRandomBlock(canBeSolid) {
    var value = Math.floor(Math.random() * (canBeSolid ? 10 : 8)) - (canBeSolid ? 2 : 0);
    if(value === 0) return getRandomBlock(canBeSolid); //value cannot be 0, try again.
    return value;
}
function dropBlock(value, column) {
    //find the lowest point it can sit.
    var yPos = -1;
    for (var y = 6; y >= 0; y--) {
        if (board[y][column] === 0) {
            yPos = y;
            break;
        }
    }
    if (yPos === -1) {
        //cannot place block, column full
        return false;
    }
    board[yPos][column] = value;

    var comboMultiplier = 1;
    var pointsEarned = 0;
    do {
        pointsEarned = detectScoring();
        score += pointsEarned * comboMultiplier;
        shakedownBoard();
        comboMultiplier *= 2;
    } while (pointsEarned > 0);

    return true;
}
function detectScoring() {
    //check vertical
    //how tall is each stack?
    var toPop = [];
    for (var x = 0; x < 7; x++) {
        var stackHeight = 7;
        for (var y = 6; y >= 0; y--) {
            if (board[y][x] === 0) {
                stackHeight = 6 - y;
                break;
            }
        }
        if (stackHeight <= 0) continue;
        //are there any in the stack that match the stack height
        var poppingWillOccur = false;
        for (var y = 0; y < 7; y++) {
            if (board[y][x] === stackHeight) {
                toPop.push({ x: x, y: y });
                poppingWillOccur = true;
            }
        }
        if (poppingWillOccur) {
            //break blank blocks by one level

            for (var y = 0; y < 7; y++) {
                if (board[y][x] < 0) {
                    toPop.push({ x: x, y: y });
                }
            }
        }
    }
    //check horizontal groups
    for (var y = 6; y >= 0; y--) { //start from the bottom up
        const groups = [[]]
        var buildingGroupIndex = 0;
        for (var x = 0; x < 7; x++) {
            if (groups[buildingGroupIndex].length === 0) {
                //if current group is empty
                if (board[y][x] === 0) continue;
                groups[buildingGroupIndex].push({
                    x: x,
                    y: y,
                    v: board[y][x]
                });
            } else {
                //current group has at least one element in it
                if (board[y][x] === 0) {
                    if (x < 6) {
                        //if we're not in the last column, create a new group for the next stuff
                        buildingGroupIndex++;
                        groups.push([]);
                    }
                    continue;
                } else {
                    groups[buildingGroupIndex].push({
                        x: x,
                        y: y,
                        v: board[y][x]
                    });
                }
            }
        }
        for (var g = 0; g < groups.length; g++) {
            var popWillOccurrInGroup = false;
            for (var j = 0; j < groups[g].length; j++) {
                if (groups[g].length === groups[g][j].v) {
                    popWillOccurrInGroup = true;
                    toPop.push({
                        x: groups[g][j].x,
                        y: groups[g][j].y
                    })
                }
            }
            if (popWillOccurrInGroup) {
                for (var j = 0; j < groups[g].length; j++) {
                    if (groups[g][j].v < 0) {
                        toPop.push({
                            x: groups[g][j].x,
                            y: groups[g][j].y
                        })
                    }
                }
            }
        }
    }
    var points = 0;
    for (var j = 0; j < toPop.length; j++) {
        const value = board[toPop[j].y][toPop[j].x]
        if (value < 0) {
            var newValue = value + 1;
            if (newValue === 0) {
                newValue = Math.floor(Math.random() * 7) + 1
            }
            board[toPop[j].y][toPop[j].x] = newValue;
        } else {
            points += board[toPop[j].y][toPop[j].x];
            board[toPop[j].y][toPop[j].x] = 0;

        }
    }

    return points;
}
function shakedownBoard() {
    for (var x = 0; x < 7; x++) { //loop through each column

        for (var y = 6; y >= 0; y--) {
            //check to see if we can push this element down
            if (y === 6) continue; // can't push any further than bottom
            const below = board[y + 1][x];
            if (below === 0) {
                //airspace directly below

                //get top of stack index and swap it with current.
                var newPos = -1;
                for (var a = 6; a >= 0; a--) {
                    if (board[a][x] === 0) {
                        newPos = a;
                        break;
                    }
                }
                if (newPos === -1) {
                    //cannot place block, column full
                    system.exit(); // shouldn't ever happen in a shakedown.
                }


                //do the swap
                board[newPos][x] = board[y][x];
                board[y][x] = 0;
                
            }


        }
    }
}
function getBlockColor(value){
    switch(value){
        case 7: return chalk.blue;
        case 6: return chalk.cyanBright;
        case 5: return chalk.magenta;
        case 4: return chalk.red;
        case 3: return chalk.yellow;
        case 2: return chalk.yellowBright;
        case 1: return chalk.greenBright;
        case 0: return chalk.black;
        case -1: return chalk.white;
        case -2: return chalk.white;
    }
}


function paintBoard() {
    console.clear();

    //paint the placing row;
    for(var x = 0;x < 7;x++)
        if(x === cursorX)
            process.stdout.write(`${placing} `);
        else
            process.stdout.write('  '); //semi solid

    process.stdout.write('\n');


    for (var y = 0; y < 7; y++) {

        for (var x = 0; x < 7; x++) {
            var charToPrint = ' ';
            switch (board[y][x]) {
                case 0:
                    charToPrint = ' ';
                    break;
                case -1:
                    charToPrint = '\u2591'; //semi solid
                    break;
                case -2:
                    charToPrint = '\u2593'; // dark block
                    break;
                default:
                    charToPrint = `${board[y][x]}`
            }
            process.stdout.write(`${getBlockColor(board[y][x])(charToPrint)} `)

        }
        process.stdout.write('\n');
    }
    process.stdout.write('-------------\n\nScore: ' + score + '\n');
}
paintBoard();