// This script will remove all videos from watch later list 
//
// Usage
//
// #1 go to https://www.youtube.com/playlist?list=WL
// #2 run following script
//    adjust REMOVE_BUTTON_TEXT to your language (default is english)

(async function() {
  const REMOVE_BUTTON_TEXT = "Remove from"
  
  const sleep = (timeout) => new Promise(res => setTimeout(res, timeout))
  const untilDefined = async (factory, timeout = 100) => {
    while (true) {
      let value = factory()
      if (value != null) return value
      await sleep(timeout)
    }
  }

  console.info("start...")
  while(true) {
    let videos = document.querySelectorAll('#primary ytd-playlist-video-renderer')
    if(videos.length == 0) break;
    
    for (let videoElement of videos) {
      let videoTitle = videoElement.querySelector('a#video-title')
      console.info("remove: " + videoTitle.innerText)
      console.info("        " + videoTitle.href)

      let actionMenu = videoElement.querySelector('#menu')
      let actionMenuButton = actionMenu.querySelector('#button');

      console.debug("click actionMenuButton")
      actionMenuButton.click();
      let removeButton = await untilDefined(() => document.evaluate('//span[contains(text(), "' + REMOVE_BUTTON_TEXT + '")]',
        actionMenu, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue);

      console.debug("click removeButton")
      removeButton.click();
      await sleep(200)
    }
  } 
  console.info("done!")
})();