dioxus/packages/liveview/src/interpreter.js

function main() {
  let root = window.document.getElementById("main");

  if (root != null) {
    // create a new ipc
    window.ipc = new IPC(root);

    window.ipc.send(serializeIpcMessage("initialize"));
  }
}

class IPC {
  constructor(root) {
    // connect to the websocket
    window.interpreter = new Interpreter(root);

    this.ws = new WebSocket(WS_ADDR);

    this.ws.onopen = () => {
      console.log("Connected to the websocket");
    };

    this.ws.onerror = (err) => {
      console.error("Error: ", err);
    };

    this.ws.onmessage = (event) => {
      let edits = JSON.parse(event.data);
      window.interpreter.handleEdits(edits);
    };
  }

  send(msg) {
    this.ws.send(msg);
  }
}

class Interpreter {
  constructor(root) {
    this.root = root;
    this.stack = [root];
    this.listeners = {};
    this.handlers = {};
    this.lastNodeWasText = false;
    this.nodes = [root];
  }
  top() {
    return this.stack[this.stack.length - 1];
  }
  pop() {
    return this.stack.pop();
  }
  PushRoot(root) {
    const node = this.nodes[root];
    this.stack.push(node);
  }
  AppendChildren(many) {
    let root = this.stack[this.stack.length - (1 + many)];
    let to_add = this.stack.splice(this.stack.length - many);
    for (let i = 0; i < many; i++) {
      root.appendChild(to_add[i]);
    }
  }
  ReplaceWith(root_id, m) {
    let root = this.nodes[root_id];
    let els = this.stack.splice(this.stack.length - m);
    root.replaceWith(...els);
  }
  InsertAfter(root, n) {
    let old = this.nodes[root];
    let new_nodes = this.stack.splice(this.stack.length - n);
    old.after(...new_nodes);
  }
  InsertBefore(root, n) {
    let old = this.nodes[root];
    let new_nodes = this.stack.splice(this.stack.length - n);
    old.before(...new_nodes);
  }
  Remove(root) {
    let node = this.nodes[root];
    if (node !== undefined) {
      node.remove();
    }
  }
  CreateTextNode(text, root) {
    // todo: make it so the types are okay
    const node = document.createTextNode(text);
    this.nodes[root] = node;
    this.stack.push(node);
  }
  CreateElement(tag, root) {
    const el = document.createElement(tag);
    // el.setAttribute("data-dioxus-id", `${root}`);
    this.nodes[root] = el;
    this.stack.push(el);
  }
  CreateElementNs(tag, root, ns) {
    let el = document.createElementNS(ns, tag);
    this.stack.push(el);
    this.nodes[root] = el;
  }
  CreatePlaceholder(root) {
    let el = document.createElement("pre");
    el.hidden = true;
    this.stack.push(el);
    this.nodes[root] = el;
  }
  NewEventListener(event_name, root, handler) {
    const element = this.nodes[root];
    element.setAttribute("data-dioxus-id", `${root}`);
    if (this.listeners[event_name] === undefined) {
      this.listeners[event_name] = 0;
      this.handlers[event_name] = handler;
      this.root.addEventListener(event_name, handler);
    } else {
      this.listeners[event_name]++;
    }
  }
  RemoveEventListener(root, event_name) {
    const element = this.nodes[root];
    element.removeAttribute(`data-dioxus-id`);
    this.listeners[event_name]--;
    if (this.listeners[event_name] === 0) {
      this.root.removeEventListener(event_name, this.handlers[event_name]);
      delete this.listeners[event_name];
      delete this.handlers[event_name];
    }
  }
  SetText(root, text) {
    this.nodes[root].textContent = text;
  }
  SetAttribute(root, field, value, ns) {
    const name = field;
    const node = this.nodes[root];
    if (ns === "style") {
      // @ts-ignore
      node.style[name] = value;
    } else if (ns != null || ns != undefined) {
      node.setAttributeNS(ns, name, value);
    } else {
      switch (name) {
        case "value":
          if (value !== node.value) {
            node.value = value;
          }
          break;
        case "checked":
          node.checked = value === "true";
          break;
        case "selected":
          node.selected = value === "true";
          break;
        case "dangerous_inner_html":
          node.innerHTML = value;
          break;
        default:
          // https://github.com/facebook/react/blob/8b88ac2592c5f555f315f9440cbb665dd1e7457a/packages/react-dom/src/shared/DOMProperty.js#L352-L364
          if (value === "false" && bool_attrs.hasOwnProperty(name)) {
            node.removeAttribute(name);
          } else {
            node.setAttribute(name, value);
          }
      }
    }
  }
  RemoveAttribute(root, name) {
    const node = this.nodes[root];

    if (name === "value") {
      node.value = "";
    } else if (name === "checked") {
      node.checked = false;
    } else if (name === "selected") {
      node.selected = false;
    } else if (name === "dangerous_inner_html") {
      node.innerHTML = "";
    } else {
      node.removeAttribute(name);
    }
  }
  handleEdits(edits) {
    this.stack.push(this.root);
    for (let edit of edits) {
      this.handleEdit(edit);
    }
  }
  handleEdit(edit) {
    switch (edit.type) {
      case "PushRoot":
        this.PushRoot(edit.root);
        break;
      case "AppendChildren":
        this.AppendChildren(edit.many);
        break;
      case "ReplaceWith":
        this.ReplaceWith(edit.root, edit.m);
        break;
      case "InsertAfter":
        this.InsertAfter(edit.root, edit.n);
        break;
      case "InsertBefore":
        this.InsertBefore(edit.root, edit.n);
        break;
      case "Remove":
        this.Remove(edit.root);
        break;
      case "CreateTextNode":
        this.CreateTextNode(edit.text, edit.root);
        break;
      case "CreateElement":
        this.CreateElement(edit.tag, edit.root);
        break;
      case "CreateElementNs":
        this.CreateElementNs(edit.tag, edit.root, edit.ns);
        break;
      case "CreatePlaceholder":
        this.CreatePlaceholder(edit.root);
        break;
      case "RemoveEventListener":
        this.RemoveEventListener(edit.root, edit.event_name);
        break;
      case "NewEventListener":
        // this handler is only provided on desktop implementations since this
        // method is not used by the web implementation
        let handler = (event) => {
          let target = event.target;
          if (target != null) {
            let realId = target.getAttribute(`data-dioxus-id`);
            let shouldPreventDefault = target.getAttribute(
              `dioxus-prevent-default`
            );

            if (event.type === "click") {
              // todo call prevent default if it's the right type of event
              if (shouldPreventDefault !== `onclick`) {
                if (target.tagName === "A") {
                  event.preventDefault();
                  const href = target.getAttribute("href");
                  if (href !== "" && href !== null && href !== undefined) {
                    window.ipc.send(
                      serializeIpcMessage("browser_open", { href })
                    );
                  }
                }
              }

              // also prevent buttons from submitting
              if (target.tagName === "BUTTON") {
                event.preventDefault();
              }
            }
            // walk the tree to find the real element
            while (realId == null) {
              // we've reached the root we don't want to send an event
              if (target.parentElement === null) {
                return;
              }

              target = target.parentElement;
              realId = target.getAttribute(`data-dioxus-id`);
            }

            shouldPreventDefault = target.getAttribute(
              `dioxus-prevent-default`
            );

            let contents = serialize_event(event);

            if (shouldPreventDefault === `on${event.type}`) {
              event.preventDefault();
            }
            if (event.type === "submit") {
              event.preventDefault();
            }

            if (target.tagName === "FORM") {
              for (let x = 0; x < target.elements.length; x++) {
                let element = target.elements[x];
                let name = element.getAttribute("name");
                if (name != null) {
                  if (element.getAttribute("type") === "checkbox") {
                    // @ts-ignore
                    contents.values[name] = element.checked ? "true" : "false";
                  } else {
                    // @ts-ignore
                    contents.values[name] =
                      element.value ?? element.textContent;
                  }
                }
              }
            }

            if (realId == null) {
              return;
            }
            window.ipc.send(
              serializeIpcMessage("user_event", {
                event: edit.event_name,
                mounted_dom_id: parseInt(realId),
                contents: contents,
              })
            );
          }
        };
        this.NewEventListener(edit.event_name, edit.root, handler);
        break;
      case "SetText":
        this.SetText(edit.root, edit.text);
        break;
      case "SetAttribute":
        this.SetAttribute(edit.root, edit.field, edit.value, edit.ns);
        break;
      case "RemoveAttribute":
        this.RemoveAttribute(edit.root, edit.name);
        break;
    }
  }
}

function serialize_event(event) {
  switch (event.type) {
    case "copy":
    case "cut":
    case "past": {
      return {};
    }
    case "compositionend":
    case "compositionstart":
    case "compositionupdate": {
      let { data } = event;
      return {
        data,
      };
    }
    case "keydown":
    case "keypress":
    case "keyup": {
      let {
        charCode,
        key,
        altKey,
        ctrlKey,
        metaKey,
        keyCode,
        shiftKey,
        location,
        repeat,
        which,
      } = event;
      return {
        char_code: charCode,
        key: key,
        alt_key: altKey,
        ctrl_key: ctrlKey,
        meta_key: metaKey,
        key_code: keyCode,
        shift_key: shiftKey,
        location: location,
        repeat: repeat,
        which: which,
        locale: "locale",
      };
    }
    case "focus":
    case "blur": {
      return {};
    }
    case "change": {
      let target = event.target;
      let value;
      if (target.type === "checkbox" || target.type === "radio") {
        value = target.checked ? "true" : "false";
      } else {
        value = target.value ?? target.textContent;
      }
      return {
        value: value,
        values: {},
      };
    }
    case "input":
    case "invalid":
    case "reset":
    case "submit": {
      let target = event.target;
      let value = target.value ?? target.textContent;
      if (target.type === "checkbox") {
        value = target.checked ? "true" : "false";
      }
      return {
        value: value,
        values: {},
      };
    }
    case "click":
    case "contextmenu":
    case "doubleclick":
    case "drag":
    case "dragend":
    case "dragenter":
    case "dragexit":
    case "dragleave":
    case "dragover":
    case "dragstart":
    case "drop":
    case "mousedown":
    case "mouseenter":
    case "mouseleave":
    case "mousemove":
    case "mouseout":
    case "mouseover":
    case "mouseup": {
      const {
        altKey,
        button,
        buttons,
        clientX,
        clientY,
        ctrlKey,
        metaKey,
        offsetX,
        offsetY,
        pageX,
        pageY,
        screenX,
        screenY,
        shiftKey,
      } = event;
      return {
        alt_key: altKey,
        button: button,
        buttons: buttons,
        client_x: clientX,
        client_y: clientY,
        ctrl_key: ctrlKey,
        meta_key: metaKey,
        offset_x: offsetX,
        offset_y: offsetY,
        page_x: pageX,
        page_y: pageY,
        screen_x: screenX,
        screen_y: screenY,
        shift_key: shiftKey,
      };
    }
    case "pointerdown":
    case "pointermove":
    case "pointerup":
    case "pointercancel":
    case "gotpointercapture":
    case "lostpointercapture":
    case "pointerenter":
    case "pointerleave":
    case "pointerover":
    case "pointerout": {
      const {
        altKey,
        button,
        buttons,
        clientX,
        clientY,
        ctrlKey,
        metaKey,
        pageX,
        pageY,
        screenX,
        screenY,
        shiftKey,
        pointerId,
        width,
        height,
        pressure,
        tangentialPressure,
        tiltX,
        tiltY,
        twist,
        pointerType,
        isPrimary,
      } = event;
      return {
        alt_key: altKey,
        button: button,
        buttons: buttons,
        client_x: clientX,
        client_y: clientY,
        ctrl_key: ctrlKey,
        meta_key: metaKey,
        page_x: pageX,
        page_y: pageY,
        screen_x: screenX,
        screen_y: screenY,
        shift_key: shiftKey,
        pointer_id: pointerId,
        width: width,
        height: height,
        pressure: pressure,
        tangential_pressure: tangentialPressure,
        tilt_x: tiltX,
        tilt_y: tiltY,
        twist: twist,
        pointer_type: pointerType,
        is_primary: isPrimary,
      };
    }
    case "select": {
      return {};
    }
    case "touchcancel":
    case "touchend":
    case "touchmove":
    case "touchstart": {
      const { altKey, ctrlKey, metaKey, shiftKey } = event;
      return {
        // changed_touches: event.changedTouches,
        // target_touches: event.targetTouches,
        // touches: event.touches,
        alt_key: altKey,
        ctrl_key: ctrlKey,
        meta_key: metaKey,
        shift_key: shiftKey,
      };
    }
    case "scroll": {
      return {};
    }
    case "wheel": {
      const { deltaX, deltaY, deltaZ, deltaMode } = event;
      return {
        delta_x: deltaX,
        delta_y: deltaY,
        delta_z: deltaZ,
        delta_mode: deltaMode,
      };
    }
    case "animationstart":
    case "animationend":
    case "animationiteration": {
      const { animationName, elapsedTime, pseudoElement } = event;
      return {
        animation_name: animationName,
        elapsed_time: elapsedTime,
        pseudo_element: pseudoElement,
      };
    }
    case "transitionend": {
      const { propertyName, elapsedTime, pseudoElement } = event;
      return {
        property_name: propertyName,
        elapsed_time: elapsedTime,
        pseudo_element: pseudoElement,
      };
    }
    case "abort":
    case "canplay":
    case "canplaythrough":
    case "durationchange":
    case "emptied":
    case "encrypted":
    case "ended":
    case "error":
    case "loadeddata":
    case "loadedmetadata":
    case "loadstart":
    case "pause":
    case "play":
    case "playing":
    case "progress":
    case "ratechange":
    case "seeked":
    case "seeking":
    case "stalled":
    case "suspend":
    case "timeupdate":
    case "volumechange":
    case "waiting": {
      return {};
    }
    case "toggle": {
      return {};
    }
    default: {
      return {};
    }
  }
}
function serializeIpcMessage(method, params = {}) {
  return JSON.stringify({ method, params });
}
const bool_attrs = {
  allowfullscreen: true,
  allowpaymentrequest: true,
  async: true,
  autofocus: true,
  autoplay: true,
  checked: true,
  controls: true,
  default: true,
  defer: true,
  disabled: true,
  formnovalidate: true,
  hidden: true,
  ismap: true,
  itemscope: true,
  loop: true,
  multiple: true,
  muted: true,
  nomodule: true,
  novalidate: true,
  open: true,
  playsinline: true,
  readonly: true,
  required: true,
  reversed: true,
  selected: true,
  truespeed: true,
};