function echeck(str) {
    var at = "@";
    var dot = ".";
    var lat = str.indexOf(at);
    var lstr = str.length;
    var ldot = str.indexOf(dot);
    if (str.indexOf(at) == -1) {
        alert("Invalid E-mail Address");
        return false;
    }

    if (str.indexOf(at) == -1 || str.indexOf(at) == 0 || str.indexOf(at) == lstr) {
        alert("Invalid E-mail Address");
        return false;
    }

    if (str.indexOf(dot) == -1 || str.indexOf(dot) == 0 || str.indexOf(dot) == lstr) {
        alert("Invalid E-mail Address");
        return false;
    }

    if (str.indexOf(at, (lat + 1)) != -1) {
        alert("Invalid E-mail Address");
        return false;
    }

    if (str.substring(lat - 1, lat) == dot || str.substring(lat + 1, lat + 2) == dot) {
        alert("Invalid E-mail Address");
        return false;
    }

    if (str.indexOf(dot, (lat + 2)) == -1) {
        alert("Invalid E-mail Address");
        return false;
    }

    if (str.indexOf(" ") != -1) {
        alert("Invalid E-mail Address");
        return false;
    }

    return true;
}

function ValidateForm() {
    var to = document.getElementById("toField");
    if (to.value == "0") {
        alert("Please select a recipient.");
        to.focus();
        return false;
    }

    var name = document.getElementById("textbox_name");

    if (name.value == null || name.value == "" || name.value == name.defaultValue) {
        alert("Please enter your name.");
        name.focus();
        return false;
    }


    var emailID = document.getElementById("textbox_email");

    if ((emailID.value == null) || (emailID.value == "") || (emailID.value == emailID.defaultValue)) {
        alert("Please Enter your Email Address.");
        emailID.focus();
        return false;
    }
    if (echeck(emailID.value) == false) {
        emailID.value = "";
        emailID.focus();
        return false;
    }

    var msg = document.getElementById("textbox_message");
    if ((msg.value == null) || (msg.value == "")) {
        alert("Please enter a message.");
        msg.focus();
        return false;
    }
    return true;
}

function blankOut(field) {
    if (field.value == field.defaultValue) {
        field.value = "";
    }

}

function unBlank(field) {
    if (field.value == "") {
        field.value = field.defaultValue;
    }
}

function image_clear_onClick() {
    var toField = document.getElementById("toField");
    toField.value = "0";

    var name = document.getElementById("textbox_name");
    name.value = name.defaultValue;

    var email = document.getElementById("textbox_email");
    email.value = email.defaultValue;

    var phone = document.getElementById("textbox_phone");
    phone.value = phone.defaultValue;

    var company = document.getElementById("textbox_company");
    company.value = company.defaultValue;

    var message = document.getElementById("textbox_message");
    message.value = "";
}
function disableInputs() {
    var send = document.getElementById("ctl00_MainContent_lnk_Send");
    send.style.color = "gray";
    send.style.cursor = "default";
    send.onclick = null;

    var clear = document.getElementById("lnk_Clear");
    clear.style.color = "gray";
    clear.style.cursor = "default";
    clear.onclick = null;


    var toField = document.getElementById("toField");
    toField.readOnly = true;

    var name = document.getElementById("textbox_name");
    name.readOnly = true;

    var email = document.getElementById("textbox_email");
    email.readOnly = true;

    var phone = document.getElementById("textbox_phone");
    phone.readOnly = true;

    var company = document.getElementById("textbox_company");
    company.readOnly = true;

    var message = document.getElementById("textbox_message");
    message.readOnly = true;
}
function image_send_onClick() {
    if (ValidateForm()) {
        disableInputs();
        FormPostback();
    }
}

function hideInputs() {
    var inputs = document.getElementById("inputFields");
    inputs.style.display = "none";

    var sent = document.getElementById("message_sent");
    sent.style.display = "block";

}
function showInputs() {
    image_clear_onClick();
    var inputs = document.getElementById("inputFields");
    inputs.style.display = "block";

    var sent = document.getElementById("message_sent");
    sent.style.display = "none";
}
/**
* DHTML phone number validation script. Courtesy of SmartWebby.com (http://www.smartwebby.com/dhtml/)
*/
// Declaring required variables
var digits = "0123456789";
// non-digit characters which are allowed in phone numbers
var phoneNumberDelimiters = "()- ";
// characters which are allowed in international phone numbers
// (a leading + is OK)
var validWorldPhoneChars = phoneNumberDelimiters + "+";
// Minimum no of digits in an international phone no.
var minDigitsInIPhoneNumber = 10;

function isInteger(s) {
    var i;
    for (i = 0; i < s.length; i++) {
        // Check that current character is number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) return false;
    }
    // All characters are numbers.
    return true;
}

function stripCharsInBag(s, bag) {
    var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++) {
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

function checkInternationalPhone(strPhone) {
    s = stripCharsInBag(strPhone, validWorldPhoneChars);
    return (isInteger(s) && s.length >= minDigitsInIPhoneNumber);
}