define(function (require) {

    var windingLine = require('./windingLine');

    var EPSILON = 1e-8;

    function isAroundEqual(a, b) {
        return Math.abs(a - b) < EPSILON;
    }

    function contain(points, x, y) {
        var w = 0;
        var p = points[0];

        if (!p) {
            return false;
        }

        for (var i = 1; i < points.length; i++) {
            var p2 = points[i];
            w += windingLine(p[0], p[1], p2[0], p2[1], x, y);
            p = p2;
        }

        // Close polygon
        var p0 = points[0];
        if (!isAroundEqual(p[0], p0[0]) || !isAroundEqual(p[1], p0[1])) {
            w += windingLine(p[0], p[1], p0[0], p0[1], x, y);
        }

        return w !== 0;
    }


    return {
        contain: contain
    };
});