gecko-dev/toolkit/content/widgets/text.js

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

"use strict";

// This is loaded into all XUL windows. Wrap in a block to prevent
// leaking to window scope.
{
  const { Services } = ChromeUtils.import(
    "resource://gre/modules/Services.jsm"
  );
  const MozXULTextElement = MozElements.MozElementMixin(XULTextElement);

  let gInsertSeparator = false;
  let gAlwaysAppendAccessKey = false;
  let gUnderlineAccesskey =
    Services.prefs.getIntPref("ui.key.menuAccessKey") != 0;
  if (gUnderlineAccesskey) {
    try {
      const nsIPrefLocalizedString = Ci.nsIPrefLocalizedString;
      const prefNameInsertSeparator =
        "intl.menuitems.insertseparatorbeforeaccesskeys";
      const prefNameAlwaysAppendAccessKey =
        "intl.menuitems.alwaysappendaccesskeys";

      let val = Services.prefs.getComplexValue(
        prefNameInsertSeparator,
        nsIPrefLocalizedString
      ).data;
      gInsertSeparator = val == "true";

      val = Services.prefs.getComplexValue(
        prefNameAlwaysAppendAccessKey,
        nsIPrefLocalizedString
      ).data;
      gAlwaysAppendAccessKey = val == "true";
    } catch (e) {
      gInsertSeparator = gAlwaysAppendAccessKey = true;
    }
  }

  class MozTextLabel extends MozXULTextElement {
    constructor() {
      super();
      this._lastFormattedAccessKey = null;
      this.addEventListener("click", this._onClick);
    }

    static get observedAttributes() {
      return ["accesskey"];
    }

    set textContent(val) {
      super.textContent = val;
      this._lastFormattedAccessKey = null;
      this.formatAccessKey();
    }

    get textContent() {
      return super.textContent;
    }

    attributeChangedCallback(name, oldValue, newValue) {
      if (!this.isConnectedAndReady || oldValue == newValue) {
        return;
      }

      // Note that this is only happening when "accesskey" attribute change:
      this.formatAccessKey();
    }

    _onClick(event) {
      let controlElement = this.labeledControlElement;
      if (!controlElement || this.disabled) {
        return;
      }
      controlElement.focus();
      const XUL_NS =
        "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";

      if (controlElement.namespaceURI != XUL_NS) {
        return;
      }

      if (
        (controlElement.localName == "checkbox" ||
          controlElement.localName == "radio") &&
        controlElement.getAttribute("disabled") == "true"
      ) {
        return;
      }

      if (controlElement.localName == "checkbox") {
        controlElement.checked = !controlElement.checked;
      } else if (controlElement.localName == "radio") {
        controlElement.control.selectedItem = controlElement;
      }
    }

    connectedCallback() {
      if (this.delayConnectedCallback()) {
        return;
      }

      this.formatAccessKey();
    }

    set accessKey(val) {
      this.setAttribute("accesskey", val);
      var control = this.labeledControlElement;
      if (control) {
        control.setAttribute("accesskey", val);
      }
    }

    get accessKey() {
      let accessKey = this.getAttribute("accesskey");
      return accessKey ? accessKey[0] : null;
    }

    get labeledControlElement() {
      let control = this.control;
      return control ? document.getElementById(control) : null;
    }

    set control(val) {
      this.setAttribute("control", val);
    }

    get control() {
      return this.getAttribute("control");
    }

    // This is used to match the rendering of accesskeys from nsTextBoxFrame.cpp (i.e. when the
    // label uses [value]). So this is just for when we have textContent.
    formatAccessKey() {
      // Skip doing any DOM manipulation whenever possible:
      let accessKey = this.accessKey;
      if (
        !gUnderlineAccesskey ||
        !this.isConnectedAndReady ||
        this._lastFormattedAccessKey == accessKey ||
        !this.textContent
      ) {
        return;
      }
      this._lastFormattedAccessKey = accessKey;
      if (this.accessKeySpan) {
        // Clear old accesskey
        mergeElement(this.accessKeySpan);
        this.accessKeySpan = null;
      }

      if (this.hiddenColon) {
        mergeElement(this.hiddenColon);
        this.hiddenColon = null;
      }

      if (this.accessKeyParens) {
        this.accessKeyParens.remove();
        this.accessKeyParens = null;
      }

      // If we used to have an accessKey but not anymore, we're done here
      if (!accessKey) {
        return;
      }

      let labelText = this.textContent;
      let accessKeyIndex = -1;
      if (!gAlwaysAppendAccessKey) {
        accessKeyIndex = labelText.indexOf(accessKey);
        if (accessKeyIndex < 0) {
          // Try again in upper case
          accessKeyIndex = labelText
            .toUpperCase()
            .indexOf(accessKey.toUpperCase());
        }
      } else if (labelText.endsWith(`(${accessKey.toUpperCase()})`)) {
        accessKeyIndex = labelText.length - (1 + accessKey.length); // = index of accessKey.
      }

      const HTML_NS = "http://www.w3.org/1999/xhtml";
      this.accessKeySpan = document.createElementNS(HTML_NS, "span");
      this.accessKeySpan.className = "accesskey";

      // Note that if you change the following code, see the comment of
      // nsTextBoxFrame::UpdateAccessTitle.

      // If accesskey is in the string, underline it:
      if (accessKeyIndex >= 0) {
        wrapChar(this, this.accessKeySpan, accessKeyIndex);
        return;
      }

      // If accesskey is not in string, append in parentheses
      // If end is colon, we should insert before colon.
      // i.e., "label:" -> "label(X):"
      let colonHidden = false;
      if (/:$/.test(labelText)) {
        labelText = labelText.slice(0, -1);
        this.hiddenColon = document.createElementNS(HTML_NS, "span");
        this.hiddenColon.className = "hiddenColon";
        this.hiddenColon.style.display = "none";
        // Hide the last colon by using span element.
        // I.e., label<span style="display:none;">:</span>
        wrapChar(this, this.hiddenColon, labelText.length);
        colonHidden = true;
      }
      // If end is space(U+20),
      // we should not add space before parentheses.
      let endIsSpace = false;
      if (/ $/.test(labelText)) {
        endIsSpace = true;
      }

      this.accessKeyParens = document.createElementNS(
        "http://www.w3.org/1999/xhtml",
        "span"
      );
      this.appendChild(this.accessKeyParens);
      if (gInsertSeparator && !endIsSpace) {
        this.accessKeyParens.textContent = " (";
      } else {
        this.accessKeyParens.textContent = "(";
      }
      this.accessKeySpan.textContent = accessKey.toUpperCase();
      this.accessKeyParens.appendChild(this.accessKeySpan);
      if (!colonHidden) {
        this.accessKeyParens.appendChild(document.createTextNode(")"));
      } else {
        this.accessKeyParens.appendChild(document.createTextNode("):"));
      }
    }
  }

  customElements.define("label", MozTextLabel);

  function mergeElement(element) {
    // If the element has been removed already, return:
    if (!element.isConnected) {
      return;
    }
    if (element.previousSibling instanceof Text) {
      element.previousSibling.appendData(element.textContent);
    } else {
      element.parentNode.insertBefore(element.firstChild, element);
    }
    element.remove();
  }

  function wrapChar(parent, element, index) {
    let treeWalker = document.createNodeIterator(
      parent,
      NodeFilter.SHOW_TEXT,
      null
    );
    let node = treeWalker.nextNode();
    while (index >= node.length) {
      index -= node.length;
      node = treeWalker.nextNode();
    }
    if (index) {
      node = node.splitText(index);
    }

    node.parentNode.insertBefore(element, node);
    if (node.length > 1) {
      node.splitText(1);
    }
    element.appendChild(node);
  }

  class MozTextLink extends MozXULTextElement {
    constructor() {
      super();

      this.addEventListener(
        "click",
        event => {
          if (event.button == 0 || event.button == 1) {
            this.open(event);
          }
        },
        true
      );

      this.addEventListener("keypress", event => {
        if (event.keyCode != KeyEvent.DOM_VK_RETURN) {
          return;
        }
        this.click();
      });
    }

    connectedCallback() {
      this.classList.add("text-link");
    }

    set href(val) {
      this.setAttribute("href", val);
    }

    get href() {
      return this.getAttribute("href");
    }

    open(aEvent) {
      var href = this.href;
      if (!href || this.disabled || aEvent.defaultPrevented) {
        return;
      }

      var uri = null;
      try {
        const nsISSM = Ci.nsIScriptSecurityManager;
        const secMan = Cc["@mozilla.org/scriptsecuritymanager;1"].getService(
          nsISSM
        );

        uri = Services.io.newURI(href);

        let principal;
        if (this.getAttribute("useoriginprincipal") == "true") {
          principal = this.nodePrincipal;
        } else {
          principal = secMan.createNullPrincipal({});
        }
        try {
          secMan.checkLoadURIWithPrincipal(
            principal,
            uri,
            nsISSM.DISALLOW_INHERIT_PRINCIPAL
          );
        } catch (ex) {
          var msg =
            "Error: Cannot open a " +
            uri.scheme +
            ": link using \
                         the text-link binding.";
          Cu.reportError(msg);
          return;
        }

        const cID = "@mozilla.org/uriloader/external-protocol-service;1";
        const nsIEPS = Ci.nsIExternalProtocolService;
        var protocolSvc = Cc[cID].getService(nsIEPS);

        // if the scheme is not an exposed protocol, then opening this link
        // should be deferred to the system's external protocol handler
        if (!protocolSvc.isExposedProtocol(uri.scheme)) {
          protocolSvc.loadURI(uri, principal);
          aEvent.preventDefault();
          return;
        }
      } catch (ex) {
        Cu.reportError(ex);
      }

      aEvent.preventDefault();
      href = uri ? uri.spec : href;

      // Try handing off the link to the host application, e.g. for
      // opening it in a tabbed browser.
      var linkHandled = Cc["@mozilla.org/supports-PRBool;1"].createInstance(
        Ci.nsISupportsPRBool
      );
      linkHandled.data = false;
      let { shiftKey, ctrlKey, metaKey, altKey, button } = aEvent;
      let data = { shiftKey, ctrlKey, metaKey, altKey, button, href };
      Services.obs.notifyObservers(
        linkHandled,
        "handle-xul-text-link",
        JSON.stringify(data)
      );
      if (linkHandled.data) {
        return;
      }

      // otherwise, fall back to opening the anchor directly
      var win = window;
      if (window.isChromeWindow) {
        while (win.opener && !win.opener.closed) {
          win = win.opener;
        }
      }
      win.open(href, "_blank", "noopener");
    }
  }

  customElements.define("text-link", MozTextLink, { extends: "label" });
}