// ==UserScript==
// @name     Auto Facebook Marketplace Messanger
// @version  1
// @grant    GM.getValue
// @grant    GM.setValue
// @run-at document-idle
// @include https://www.facebook.com/marketplace*/search/*
// ==/UserScript==



function sleep (delay) {
  return new Promise(resolve => setTimeout(resolve, delay));
}

function setNativeValue(element, value) {
    let lastValue = element.value;
    element.value = value;
    let event = new Event("input", { target: element, bubbles: true });
    // React 15
    event.simulated = true;
    // React 16
    let tracker = element._valueTracker;
    if (tracker) {
        tracker.setValue(lastValue);
    }
    element.dispatchEvent(event);
}

var listingsViewed = [];


var interval;


var main_script = function() {
  var elements = document.querySelectorAll("*[data-testid='marketplace_feed_item']");
  console.log(elements);
  console.log("Going through " + elements.length + " listings....");


  if (elements.length > 0) {
    clearInterval(interval);

    (async () => {
      for(var i=0;i<elements.length; ++i) {
        if (elements[i].parentElement.previousSibling != null && elements[i].parentElement.previousSibling.innerHTML == "You Might Also Like") {
          console.log("we reached the the extra listing stuff... quitting.");
          break;
        }

        if (elements[i].parentElement.parentElement.previousSibling != null && elements[i].parentElement.parentElement.previousSibling.innerText == "Results From Marketplace Stores\nSee All") {
          console.log("we reached facebook marketplace store ads... quitting.");
          break;
        }


        let page_visited = await GM.getValue("visited_"+elements[i].href, false);
        if (page_visited) {
          console.log("We have visited " + elements[i].title + " - " + elements[i].href + " before - skipping.");
        } else {
          console.log("We have never visited " + elements[i].title + " - " + elements[i].href + " before, executing script.");
          GM.setValue("visited_"+elements[i].href, true);

          elements[i].click();
          await sleep(1000);

          var fullComponent = document.querySelector("[data-testid='marketplace_pdp_component']");

          let expandButton = document.querySelector("*[title='More']");

          if (expandButton !== null) {
            expandButton.click();
          }

          let details = "";
          if (fullComponent.querySelector("p span") === null) {
            details = "no detailed description";
          } else {
            details = fullComponent.querySelector("p span").innerText;
          }


          console.log("Details of this listing: " + details);


          listingsViewed.push({ "title": elements[i].title, "details": details, url: elements[i].href })

          console.log("selecting text box");
          var inputBox = document.querySelector("*[placeholder='Send a private message...']");

          if (inputBox !== null) {
            console.log("filling in text box");
            setNativeValue(inputBox, "how old is this?");
            console.log("Firing reactJS update to run");
            inputBox.dispatchEvent(new Event('input', { bubbles: true }));

            await sleep(1000);
            console.log("hitting submit button");
            var submitButton = fullComponent.querySelectorAll("button")[1];
            //submitButton.click();
            await sleep(1000);

          } else {
            console.log("no text box - did you already manually message this posting already?");
          }


          //var close_button = document.querySelector("*[title='Close']");
          //close_button.click();
          await sleep(500);
        }
      }

      console.log(listingsViewed);
      console.log(JSON.stringify(listingsViewed));
    })();
  }
}

console.log("greasemonkey script firing..");

if (window.confirm("Do you really want to run the auto-responder?")) {
  interval = setInterval(main_script, 5000);
}


//
/*
function resolved(result) {
  console.log('Resolved');
}

function rejected(result) {
  console.error(result);
}*/


//GM.setValue("visited_"+window.location.href, true);
/*(async () => {
  let page_visited = await GM.getValue("visited_"+window.location.href, false);
	if (page_visited) {
  	alert("We have visited " + window.location.href + " before.");
	} else {
	  alert("We have never visited " + window.location.href + " before.");
	  GM.setValue("visited_"+window.location.href, true);
	}

	window.addEventListener('popstate', (event) => {
 		console.log("location: " + document.location + ", state: " + JSON.stringify(event.state));
	});
})();*/