diff --git a/public/javascripts/codejom_timeout.js b/public/javascripts/codejom_timeout.js
new file mode 100644
--- /dev/null
+++ b/public/javascripts/codejom_timeout.js
@@ -0,0 +1,58 @@
+var CodejomTimeout = {
+
+    timeStarted: null,
+
+    inputDataDuration: 5,  // 5 minutes
+
+    timeouts: [],
+
+    updateProblemMessages: function() {
+	CodejomTimeout.timeouts.each(function(data) {
+	    if(data.timeout==null) {
+		$("problem-submission-form-" + data.problem).hide();
+	    } else if(data.timeout==0) {
+		$("problem-timing-message-" + data.problem).innerHTML = 
+		    "The recent input data is expired.  Please download a new one.  You'll have 5 minute to submit.";
+		$("problem-submission-form-" + data.problem).hide();
+	    } else {
+		$("problem-timing-message-" + data.problem).innerHTML = 
+		    "You have about " + parseInt(data.timeout/60) + " minute(s) and " + parseInt(data.timeout % 60) + " second(s) to submit.";
+		$("problem-submission-form-" + data.problem).show();
+	    }
+	});
+    },
+
+    refreshProblemMessages: function() {
+	var timeElapsed = ((new Date()).getTime() - CodejomTimeout.timeStarted)/1000;
+	// update timeout info
+	CodejomTimeout.timeouts.each(function(data) {
+	    if(data.timeout > timeElapsed) {
+		data.timeout -= timeElapsed;
+	    } else if(data.timeout > 0) {
+		data.timeout = 0;
+	    }
+	});	
+
+	CodejomTimeout.updateProblemMessages();
+	CodejomTimeout.registerRefreshEvent();
+    },
+
+    registerRefreshEvent: function() {
+	CodejomTimeout.timeStarted = (new Date()).getTime(),
+	setTimeout(function () {
+	    CodejomTimeout.refreshProblemMessages();
+	}, 2700);
+    },
+
+    updateTimeoutAfterDownloadClick: function(problem) {
+	CodejomTimeout.timeouts
+	    .filter(function(data) { return data.problem==problem; })
+	    .each(function(data) {
+		if(data.timeout==0 || data.timeout==null) {
+		    // TODO: use value from rails app.
+		    data.timeout = CodejomTimeout.inputDataDuration * 60;  
+		}
+	    });
+	CodejomTimeout.updateProblemMessages();
+    },
+};