// ==UserScript==
// @name         Save Unsent AI Prompts
// @namespace    Violent Monkey Scripts
// @version      1.0
// @description  Auto-save unsent AI prompts as drafts
// @match        https://chatgpt.com/*
// @grant        none
// ==/UserScript==


(async function(){
 for await (let newTarget of targetDivs()) {
  applyHandler(newTarget);
 }
})();

function timeout(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
 }

 // Continuously looks for new #prompt-textarea divs
 async function* targetDivs() {
  let found = new Set();
  while(true) {
   let divs = document.querySelectorAll('#prompt-textarea');
   for(let div of divs) {
    if(!found.has(div)) {
     found.add(div);
     yield div;
    }
   }
   await timeout(500);
  }
 }

function shouldSaveDraft(oldVal, newVal) {
  // Save if text was added or replaced (not pure deletion).
  if (newVal.length > oldVal.length) return true;
  if (newVal.length === oldVal.length && newVal !== oldVal) return true;
  return false;
}

function saveDraft(id, text) {
 localStorage.setItem('draft-'+id, text);
}

function applyHandler(div) {
 let currentId = null;
 let oldValue = '';

 // Called whenever mutations occur
 function onDivMutate() {
  let newValue = div.innerHTML.trim();
  if (!newValue) {
   // If there's nothing left, reset
   currentId = null;
   oldValue = '';
   return;
  }
  // If we had no oldValue, this is the first time we're typing => new ID
  if (!oldValue || !currentId) {
   currentId = Date.now();
  }
  // Only save if something was added (newValue got longer than oldValue)
  if(shouldSaveDraft(oldValue,newValue)) {
   saveDraft(currentId,newValue);
  }
  // Update the known current content
  oldValue = newValue;
 }

 // Observe changes in the div (childList & characterData changes)
 let observer = new MutationObserver(onDivMutate);
 observer.observe(div, {childList: true, characterData: true, subtree: true});
}