(function () {
  var wsProto = window.location.protocol === 'https:' ? 'wss:' : 'ws:';
  var ws = new WebSocket(wsProto + '//' + window.location.host + '/__WS_PATH__/__CR_ID__/__RB_ID__');
  var h = {};              // event handlers keyed as "e:eventName" or "stream_start:name" etc.
  var streams = {};        // name → {canvas, w, h, cssW, cssH, autoSize, el}
  var streamLastStart = {} // name → last stream_start message, so mountStream called late still sizes correctly

  ws.onopen = function () {
    ws.send(JSON.stringify({ type: 'viewport', width: window.innerWidth, height: window.innerHeight }));
  };

  // Apply stream_start sizing to an already-mounted stream entry.
  function applyStreamStart(st, m) {
    st.canvas.width  = m.width;
    st.canvas.height = m.height;
    st.w = m.width;
    st.h = m.height;
    // Display size = element's true CSS-pixel dimensions.
    // Replace cssText entirely so there is no max-width left to fight against.
    var dw = m.cssWidth  || m.width;
    var dh = m.cssHeight || m.height;
    st.cssW = dw;
    st.cssH = dh;
    st.canvas.style.cssText = 'display:block;outline:none;width:' + dw + 'px;height:' + dh + 'px;';
    if (st.autoSize) {
      st.el.style.width  = dw + 'px';
      st.el.style.height = dh + 'px';
    }
  }

  ws.onmessage = function (e) {
    try {
      var m = JSON.parse(e.data);

      if (m.type === 'event' && m.key) {
        (h['e:' + m.key] || []).forEach(function (f) { f(m.value); });

      } else if (m.type === 'stream_start' && m.name) {
        // Always store so mountStream() called inside the handler still gets sized.
        streamLastStart[m.name] = m;
        var st = streams[m.name];
        if (st) {
          // Stream already mounted — this is a resize/reposition update only.
          // Do NOT re-fire user handlers; that would call mountStream() again
          // and create duplicate canvases.
          applyStreamStart(st, m);
        } else {
          // First stream_start for this name: fire user handlers so the page can
          // call mountStream() to attach a canvas.
          (h['stream_start:' + m.name] || []).forEach(function (f) {
            f(m.cssWidth || m.width, m.cssHeight || m.height);
          });
          // If the handler called mountStream() just now, apply sizing immediately.
          if (streams[m.name]) {
            applyStreamStart(streams[m.name], m);
          }
        }

      } else if (m.type === 'stream_frame' && m.name) {
        var st = streams[m.name];
        if (!st) return;
        var img = new Image();
        img.onload = function () {
          if (st.canvas.width  !== img.naturalWidth)  { st.canvas.width  = img.naturalWidth;  st.w = img.naturalWidth; }
          if (st.canvas.height !== img.naturalHeight) { st.canvas.height = img.naturalHeight; st.h = img.naturalHeight; }
          st.canvas.getContext('2d').drawImage(img, 0, 0);
        };
        img.src = 'data:image/jpeg;base64,' + m.frame;

      } else if (m.type === 'done') {
        (h['e:done'] || []).forEach(function (f) { f(); });

      } else if (m.type === 'stream_stop' && m.name) {
        // Remove the canvas from DOM and clear the tracking entry so the next
        // stream_start for the same name triggers a fresh mountStream() call.
        // Without this, a stop→start cycle (e.g. element removed and re-added)
        // leaves a stale canvas in `streams` that silently receives frames while
        // subsequent mountStream() calls add new canvases on top.
        var stStopped = streams[m.name];
        if (stStopped && stStopped.canvas && stStopped.canvas.parentNode) {
          stStopped.canvas.parentNode.removeChild(stStopped.canvas);
        }
        delete streams[m.name];
        delete streamLastStart[m.name];
        (h['stream_stop:' + m.name] || []).forEach(function (f) { f(); });
      }
    } catch (ex) {}
  };

  window.remoteBrowser = {
    on: function (ev, nameOrFn, fn) {
      if (typeof nameOrFn === 'function') {
        h['e:' + ev] = h['e:' + ev] || [];
        h['e:' + ev].push(nameOrFn);
      } else {
        var k = ev + ':' + nameOrFn;
        h[k] = h[k] || [];
        h[k].push(fn);
      }
    },

    send: function (ev, data) {
      if (ws.readyState === 1) ws.send(JSON.stringify({ event: ev, data: data || {} }));
    },

    mountStream: function (name, el, opts) {
      // stream_start fires on every viewport/JPEG-dimension change; guard against
      // appending a second canvas if the stream is already mounted.
      if (streams[name]) return;

      var autoSize    = !!(opts && opts.autoSize);
      var allowScroll = !!(opts && opts.scroll);
      var allowArrows = !!(opts && opts.arrowKeys);
      var ARROW_KEYS  = { ArrowUp: 1, ArrowDown: 1, ArrowLeft: 1, ArrowRight: 1 };

      var canvas = document.createElement('canvas');
      canvas.style.cssText = 'display:block;outline:none;';
      canvas.setAttribute('tabindex', '0');
      el.appendChild(canvas);

      var st = { canvas: canvas, w: 0, h: 0, autoSize: autoSize, el: el };
      streams[name] = st;

      // If stream_start already arrived (e.g. mountStream called inside the handler),
      // apply the stored sizing now so the canvas has the right CSS dimensions immediately.
      if (streamLastStart[name]) {
        applyStreamStart(st, streamLastStart[name]);
      }

      function coords(e) {
        var r  = canvas.getBoundingClientRect();
        var sx = st.w > 0 ? st.w / r.width  : 1;
        var sy = st.h > 0 ? st.h / r.height : 1;
        return { x: Math.round((e.clientX - r.left) * sx), y: Math.round((e.clientY - r.top) * sy) };
      }

      function snd(o) {
        if (ws.readyState === 1) ws.send(JSON.stringify(o));
      }

      canvas.addEventListener('mousedown', function (e) {
        e.preventDefault();
        canvas.focus();
        var p = coords(e);
        snd({ type: 'stream_input', name: name, action: 'mousedown', x: p.x, y: p.y,
              button: e.button === 2 ? 'right' : 'left' });
      });

      canvas.addEventListener('mouseup', function (e) {
        var p = coords(e);
        snd({ type: 'stream_input', name: name, action: 'mouseup', x: p.x, y: p.y,
              button: e.button === 2 ? 'right' : 'left' });
      });

      canvas.addEventListener('mousemove', function (e) {
        var p = coords(e);
        snd({ type: 'stream_input', name: name, action: 'mousemove', x: p.x, y: p.y });
      });

      // Scroll: disabled by default to avoid accidentally scrolling the remote browser.
      // Enable with { scroll: true } in mountStream options.
      if (allowScroll) {
        canvas.addEventListener('wheel', function (e) {
          e.preventDefault();
          var p = coords(e);
          snd({ type: 'stream_input', name: name, action: 'scroll', x: p.x, y: p.y,
                deltaX: e.deltaX, deltaY: e.deltaY });
        }, { passive: false });
      }

      // Arrow keys: always preventDefault (prevent page scroll when canvas is focused),
      // but only forwarded to the remote browser when { arrowKeys: true }.
      canvas.addEventListener('keydown', function (e) {
        var isArrow = !!ARROW_KEYS[e.key];
        e.preventDefault();
        if (isArrow && !allowArrows) return;
        snd({ type: 'stream_input', name: name, action: 'keydown',
              key: e.key, code: e.code, keyCode: e.keyCode,
              modifiers: (e.altKey ? 1 : 0) | (e.ctrlKey ? 2 : 0) | (e.metaKey ? 4 : 0) | (e.shiftKey ? 8 : 0),
              charText: (e.ctrlKey || e.metaKey) ? '' : (e.key === 'Enter' ? '\r' : e.key.length === 1 ? e.key : '') });
      });

      canvas.addEventListener('keyup', function (e) {
        var isArrow = !!ARROW_KEYS[e.key];
        e.preventDefault();
        if (isArrow && !allowArrows) return;
        snd({ type: 'stream_input', name: name, action: 'keyup',
              key: e.key, code: e.code, keyCode: e.keyCode,
              modifiers: (e.altKey ? 1 : 0) | (e.ctrlKey ? 2 : 0) | (e.metaKey ? 4 : 0) | (e.shiftKey ? 8 : 0) });
      });

      canvas.addEventListener('contextmenu', function (e) { e.preventDefault(); });
    }
  };

  window.rb = window.remoteBrowser;
})();