/* ==========================================================================
 * Util.js
 *
 * Written by Kostas Symeonidis
 * Copyright (c) 2009, CyLog Software
 * ==========================================================================
 * History:
 *
 * 08.Jun.2009 Started
 * ==========================================================================
 * This is just a collection of small and useful functions
 * ==========================================================================
 * License
 * GNU General Public License version 3.0 (GPLv3)
 * ==========================================================================
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 * ==========================================================================
 */

/**
 * Returns 1 for TRUE boolean values, 0 for FALSE to be used in
 * arithmetical calculations.
 *
 * @param b
 */
function booleanToInt ( b )
{
    return b ? 1 : 0;
}

/**
 * Returns a random number between 0..n-1
 * @param n
 */
function random ( n )
{
    return Math.floor(Math.random() * n);
}

/**
 * Returns a random number between n1..n2 inclusive
 * @param n1
 * @param n2
 */
function randomRange ( n1, n2 )
{
    return Math.floor(Math.random() * (n2 - n1 + 1)) + n1;
}

/**
 * Returns a random number between -(n-1)..(n-1) except 0.
 * For exammple a n=3 will give you -3,-2,-1,1,2,3 as possible answers
 * @param n
 */
function randomSignedNoZero ( n )
{
    var i = random(n * 2) - n + 1;  // -(n-1), -(n-2), ..., 0, ..., n-1, n
    return (i < 1) ? i - 1 : i;
}

/**
 * Returns a floating point random between [0..n)
 * @param n
 */
function randomFloat ( n )
{
    return Math.random() * n;
}

/**
 * Returns a floating point random between [n1..n2)
 * @param n1 from
 * @param n2 to
 */
function randomFloatRange ( n1, n2 )
{
    return Math.random() * (n2 - n1) + n1;
}

/**
 * Returns the current time in milliseconds since 1970
 */
function timeInMillis ()
{
    return (new Date()).getTime();
}

/**
 * Returns TRUE if x is between start and finish (non inclusive)
 *
 * @param x
 * @param start
 * @param finish
 */
function inRange ( x, start, finish )
{
    return (x >= start) && (x < finish);
}