wait.js

wait = function (data) {
    var check, context, fail, freq, isResetFunction, reset, resetAllTimers, success, timers, waitInner;
    timers = {};
    resetAllTimers = function () {
        clearTimeout(timers.timer);
        return clearTimeout(timers.resetTimer);
    };
    check = data.check || null;
    freq = data.frequency || data.freq || 0;
    reset = data.reset || null;
    context = data.context || global || window.top;
    if (typeof data.success === 'function') {
        success = function () {
            resetAllTimers();
            data.success();
            return typeof data.always === "function" ? data.always() : void 0;
        };
    } else {
        success = function () {
            resetAllTimers();
            return typeof data.always === "function" ? data.always() : void 0;
        };
    }
    if (typeof data.fail === 'function') {
        fail = function () {
            resetAllTimers();
            data.fail();
            return typeof data.always === "function" ? data.always() : void 0;
        };
    } else {
        fail = function () {
            resetAllTimers();
            return typeof data.always === "function" ? data.always() : void 0;
        };
    }
    isResetFunction = typeof reset === 'function' ? true : false;
    if (!isResetFunction) {
        reset = parseInt(reset, 10);
        reset = reset > -1 ? reset : null;
    }
    if (!check) {
        if (data.id) {
            check = function () {
                return context.document.getElementById(data.id);
            };
        } else if (data.selector) {
            check = function () {
                return context.document.querySelector(data.selector);
            };
        } else {
            throw new Error("wait: no condition specified");
        }
    }
    if (check()) {
        success();
    } else if (isResetFunction && reset()) {
        fail();
    } else {
        waitInner = function (data) {
            timers.timer = setTimeout(function() {
                if (check()) {
                    success();
                } else {
                    if (isResetFunction && reset()) {
                        fail();
                    } else {
                        waitInner(data);
                    }
                }
            }, freq);
        };
        if (reset && !isResetFunction) {
            timers.resetTimer = setTimeout(function() {
                return fail();
            }, reset);
        }
        waitInner(data);
    }
};

Usage:

// with reset timer
wait({
    freq: 100,
    reset: 3000,
    check: function () {
        return window.jQuery;
    },
    success: function () {
        console.log('jQuery was found')
    },
    fail: function () {
        console.log('jQuery wasn\'t found during 3 seconds')
    },
    always: function () {
        console.log('Anyway print something')
    }
});

// with reset function
wait({
    freq: 100,
    reset: function () {
        return 2 + 2 > -1;
    },
    check: function () {
        return window.Zepto;
    },
    success: function () {
        console.log('Zepto was found')
    },
    fail: function () {
        console.log('Zepto wasn\'t found')
    },
    always: function () {
        console.log('Anyway print something')
    }
});