Exams - Tetris Figures

/* In the classical Tetris game we have 7 Tetris figures (also called "tetriminos"): I, L, J, O, Z, S and T.
 You are given a rectangular Tetris game field consisting of full end empty cells. Your task is to write
 a JavaScript function to count the number of each of these 7 tetriminos (with overlapping, without rotations).
 The input is passed as array of strings holding the game field lines. Each game field line holds only
 two letters: '-' and 'o' (empty and full cells). All game field lines have the same length. Print at the console
 the number of I, L, J, O, Z, S and T tetriminos found in the game field (with overlapping and without rotations)
 as JSON string*/

"use strict";

function solve(args) {
    var tetriminos = {"I": 0, "L": 0, "J": 0, "O": 0, "Z": 0, "S": 0, "T": 0};
    for (var i = 0; i < args.length; i += 1) {
        for (var j = 0; j < args[i].length; j += 1) {
            if (args[i][j] == 'o') {
                tetriminosCounter(args, i, j, tetriminos);
            }
        }
    }

    console.log(JSON.stringify(tetriminos));

    function tetriminosCounter(matrix, row, col, object) {
        if (row + 3 < matrix.length && matrix[row + 1][col] == 'o' &&
            matrix[row + 2][col] == 'o' && matrix[row + 3][col] == 'o') {
            object.I += 1;
        }

        if (row + 2 < matrix.length && col + 1 < matrix[row + 2].length &&
            matrix[row + 1][col] == 'o' && matrix[row + 2][col] == 'o' &&
            matrix[row + 2][col + 1] == 'o') {
            object.L += 1;
        }

        if (row + 2 < matrix.length && col - 1 >= 0 && matrix[row + 1][col] == 'o' &&
            matrix[row + 2][col] == 'o' && matrix[row + 2][col - 1] == 'o') {
            object.J += 1;
        }

        if (row + 1 < matrix.length && col + 1 < matrix[row].length &&
            matrix[row][col + 1] == 'o' && matrix[row + 1][col] == 'o' &&
            matrix[row + 1][col + 1] == 'o') {
            object.O += 1;
        }

        if (row + 1 < matrix.length && col + 2 < matrix[row].length &&
            matrix[row][col + 1] == 'o' && matrix[row + 1][col + 1] == 'o' &&
            matrix[row + 1][col + 2] == 'o') {
            object.Z += 1;
        }

        if (row + 1 < matrix.length && col - 1 >= 0 && col + 1 < matrix[row].length &&
            matrix[row][col + 1] == 'o' && matrix[row + 1][col] == 'o' &&
            matrix[row + 1][col - 1] == 'o') {
            object.S += 1;
        }

        if (row + 1 < matrix.length && col + 2 < matrix[row].length &&
            matrix[row][col + 1] == 'o' && matrix[row][col + 2] == 'o' &&
            matrix[row + 1][col + 1] == 'o') {
            object.T += 1;
        }
    }
}

solve([
    '--o--o-',
    '--oo-oo',
    'ooo-oo-',
    '-ooooo-',
    '---oo--'
]);

solve([
    '-oo',
    'ooo',
    'ooo'
]);