script.js

// ------- Simple marquee for ticker -------
(function(){
  function initTicker(){
    const el = document.getElementById("zenTicker");
    if(!el) return;
    let speed = parseFloat(el.dataset.speed || "38"); // px/sec
    let x = el.offsetWidth;
    const step = () => {
      const dt = 1/60; // 60fps
      x -= speed*dt;
      if(x < -el.scrollWidth) x = el.offsetWidth;
      el.style.transform = `translateX(${x}px)`;
      requestAnimationFrame(step);
    };
    step();
  }
  setTimeout(initTicker, 100);
})();

// ------- Teleprompter controls -------
(function(){
  let raf = null;
  let y = 0;

  function elScroll(){ return document.getElementById("prompterScroll"); }
  function elSpeed(){ return document.getElementById("pSpeed"); }

  function loop(){
    const el = elScroll();
    if(!el) return;
    const playing = (el.dataset.playing === "true");
    const speed = parseFloat(el.dataset.speed || "40"); // px/s
    const dt = 1/60;
    if(playing){
      y -= speed*dt; // scroll up
      el.style.transform = `translateY(${y}px)`;
    }
    raf = requestAnimationFrame(loop);
  }

  function togglePlay(){
    const el = elScroll(); if(!el) return;
    const playing = (el.dataset.playing === "true");
    el.dataset.playing = (!playing).toString();
  }
  function speedDelta(d){
    const el = elScroll(); if(!el) return;
    let s = parseFloat(el.dataset.speed || "40");
    s = Math.max(5, Math.min(200, s + d));
    el.dataset.speed = String(s);
    const sp = elSpeed(); if(sp) sp.textContent = `${Math.round(s)}px/s`;
  }
  function fullScreen(){
    const vp = document.querySelector(".prompter__viewport");
    if(!vp) return;
    if(!document.fullscreenElement){
      vp.requestFullscreen().catch(()=>{});
    }else{
      document.exitFullscreen().catch(()=>{});
    }
  }
  function keyHandler(e){
    if(e.key === " "){ e.preventDefault(); togglePlay(); }
    if(e.key === "ArrowUp"){ e.preventDefault(); speedDelta(+5); }
    if(e.key === "ArrowDown"){ e.preventDefault(); speedDelta(-5); }
  }
  function clickBind(){
    const play = document.getElementById("pPlayPause");
    const slow = document.getElementById("pSlower");
    const fast = document.getElementById("pFaster");
    const full = document.getElementById("pFullscreen");
    if(play) play.onclick = togglePlay;
    if(slow) slow.onclick = ()=>speedDelta(-5);
    if(fast) fast.onclick = ()=>speedDelta(+5);
    if(full) full.onclick = fullScreen;
    document.addEventListener("keydown", keyHandler);
  }

  setTimeout(()=>{
    clickBind();
    if(!raf) raf = requestAnimationFrame(loop);
  }, 120);
})();