{
    "name": "Google-Home-Page-Alert-Chrome-Extension",
    "version": "1",
    "manifest_version": 2,
    "description": "When you visit Amazon's website, alert to Google Home",
    "content_scripts": [{
      "matches": ["https://www.amazon.co.jp/*"],
      "js": ["alert.js"]
    }],
    "permissions": [ "https://script.google.com/macros/s/*", "tabs" ]
}

var pageUrl = location.pathname;
var url = [YOUR URL];

if(window.sessionStorage.getItem(["GHAlert"]) === null){
    /* セッションで最初の訪問だったときの処理 */

    // セッションに値を登録
    window.sessionStorage.setItem(["GHAlert"],["1"]);

    var msg = "無駄遣いしないようにね";    
    postGHN(url, msg);    
}else if(~pageUrl.indexOf("/gp/cart/view.html")){
    /* カートページを訪れたときの処理 */

    var msg = "それ本当に必要なの？";    
    postGHN(url, msg);
}

/* google-home-notifierにPOSTするための関数 */
function postGHN(url, msg) {
    var xhr = new XMLHttpRequest();
    msg = encodeURIComponent(msg);

    xhr.open("POST", url, true);
    xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    xhr.withCredentials = "true";    
    xhr.send("msg=" + msg);
}