/* 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";

var EXPORTED_SYMBOLS = ["AutoCompleteParent"];

const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");

// Stores the browser and actor that has the active popup, used by formfill
let currentBrowserWeakRef = null;
let currentActor = null;

let autoCompleteListeners = new Set();

function compareContext(message) {
  if (
    !currentActor ||
    (currentActor.browsingContext != message.data.browsingContext &&
      currentActor.browsingContext.top != message.data.browsingContext)
  ) {
    return false;
  }

  return true;
}

// These are two synchronous messages sent by the child.
// The browsingContext within the message data is either the one that has
// the active autocomplete popup or the top-level of the one that has
// the active autocomplete popup.
Services.ppmm.addMessageListener(
  "FormAutoComplete:GetSelectedIndex",
  message => {
    if (compareContext(message)) {
      let actor = currentActor;
      if (actor && actor.openedPopup) {
        return actor.openedPopup.selectedIndex;
      }
    }

    return -1;
  }
);

Services.ppmm.addMessageListener("FormAutoComplete:SelectBy", message => {
  if (compareContext(message)) {
    let actor = currentActor;
    if (actor && actor.openedPopup) {
      actor.openedPopup.selectBy(message.data.reverse, message.data.page);
    }
  }
});

// AutoCompleteResultView is an abstraction around a list of results.
// It implements enough of nsIAutoCompleteController and
// nsIAutoCompleteInput to make the richlistbox popup work. Since only
// one autocomplete popup should be open at a time, this is a singleton.
var AutoCompleteResultView = {
  // nsISupports
  QueryInterface: ChromeUtils.generateQI([
    Ci.nsIAutoCompleteController,
    Ci.nsIAutoCompleteInput,
  ]),

  // Private variables
  results: [],

  // The AutoCompleteParent currently showing results or null otherwise.
  currentActor: null,

  // nsIAutoCompleteController
  get matchCount() {
    return this.results.length;
  },

  getValueAt(index) {
    return this.results[index].value;
  },

  getFinalCompleteValueAt(index) {
    return this.results[index].value;
  },

  getLabelAt(index) {
    // Backwardly-used by richlist autocomplete - see getCommentAt.
    // The label is used for secondary information.
    return this.results[index].comment;
  },

  getCommentAt(index) {
    // The richlist autocomplete popup uses comment for its main
    // display of an item, which is why we're returning the label
    // here instead.
    return this.results[index].label;
  },

  getStyleAt(index) {
    return this.results[index].style;
  },

  getImageAt(index) {
    return this.results[index].image;
  },

  handleEnter(aIsPopupSelection) {
    if (this.currentActor) {
      this.currentActor.handleEnter(aIsPopupSelection);
    }
  },

  stopSearch() {},

  searchString: "",

  // nsIAutoCompleteInput
  get controller() {
    return this;
  },

  get popup() {
    return null;
  },

  _focus() {
    if (this.currentActor) {
      this.currentActor.requestFocus();
    }
  },

  // Internal JS-only API
  clearResults() {
    this.currentActor = null;
    this.results = [];
  },

  setResults(actor, results) {
    this.currentActor = actor;
    this.results = results;
  },
};

class AutoCompleteParent extends JSWindowActorParent {
  willDestroy() {
    if (this.openedPopup) {
      this.openedPopup.closePopup();
    }
  }

  static getCurrentActor() {
    return currentActor;
  }

  static getCurrentBrowser() {
    return currentBrowserWeakRef ? currentBrowserWeakRef.get() : null;
  }

  static addPopupStateListener(listener) {
    autoCompleteListeners.add(listener);
  }

  static removePopupStateListener(listener) {
    autoCompleteListeners.delete(listener);
  }

  handleEvent(evt) {
    switch (evt.type) {
      case "popupshowing": {
        this.sendAsyncMessage("FormAutoComplete:PopupOpened", {});
        break;
      }

      case "popuphidden": {
        let selectedIndex = this.openedPopup.selectedIndex;
        let selectedRowStyle =
          selectedIndex != -1
            ? AutoCompleteResultView.getStyleAt(selectedIndex)
            : "";
        this.sendAsyncMessage("FormAutoComplete:PopupClosed", {
          selectedRowStyle,
        });
        AutoCompleteResultView.clearResults();
        // adjustHeight clears the height from the popup so that
        // we don't have a big shrink effect if we closed with a
        // large list, and then open on a small one.
        this.openedPopup.adjustHeight();
        this.openedPopup = null;
        currentBrowserWeakRef = null;
        currentActor = null;
        evt.target.removeEventListener("popuphidden", this);
        evt.target.removeEventListener("popupshowing", this);
        break;
      }
    }
  }

  showPopupWithResults({ rect, dir, results }) {
    if (!results.length || this.openedPopup) {
      // We shouldn't ever be showing an empty popup, and if we
      // already have a popup open, the old one needs to close before
      // we consider opening a new one.
      return;
    }

    let browser = this.browsingContext.top.embedderElement;
    let window = browser.ownerGlobal;
    // Also check window top in case this is a sidebar.
    if (
      Services.focus.activeWindow !== window.top &&
      Services.focus.focusedWindow.top !== window.top
    ) {
      // We were sent a message from a window or tab that went into the
      // background, so we'll ignore it for now.
      return;
    }

    // Non-empty result styles
    let resultStyles = new Set(results.map(r => r.style).filter(r => !!r));
    currentBrowserWeakRef = Cu.getWeakReference(browser);
    currentActor = this;
    this.openedPopup = browser.autoCompletePopup;
    // the layout varies according to different result type
    this.openedPopup.setAttribute("resultstyles", [...resultStyles].join(" "));
    this.openedPopup.hidden = false;
    // don't allow the popup to become overly narrow
    this.openedPopup.setAttribute("width", Math.max(100, rect.width));
    this.openedPopup.style.direction = dir;

    AutoCompleteResultView.setResults(this, results);
    this.openedPopup.view = AutoCompleteResultView;
    this.openedPopup.selectedIndex = -1;

    // Reset fields that were set from the last time the search popup was open
    this.openedPopup.mInput = AutoCompleteResultView;
    // Temporarily increase the maxRows as we don't want to show
    // the scrollbar in login or form autofill popups.
    if (
      resultStyles.size &&
      (resultStyles.has("autofill-profile") || resultStyles.has("loginsFooter"))
    ) {
      this.openedPopup._normalMaxRows = this.openedPopup.maxRows;
      this.openedPopup.mInput.maxRows = 100;
    }
    this.openedPopup.addEventListener("popuphidden", this);
    this.openedPopup.addEventListener("popupshowing", this);
    this.openedPopup.openPopupAtScreenRect(
      "after_start",
      rect.left,
      rect.top,
      rect.width,
      rect.height,
      false,
      false
    );
    this.openedPopup.invalidate();
    this._maybeRecordTelemetryEvents(results);
  }

  /**
   * @param {object[]} results - Non-empty array of autocomplete results.
   */
  _maybeRecordTelemetryEvents(results) {
    let actor = this.browsingContext.currentWindowGlobal.getActor(
      "LoginManager"
    );
    actor.maybeRecordPasswordGenerationShownTelemetryEvent(results);

    // Assume the result with the start time (loginsFooter) is last.
    let lastResult = results[results.length - 1];
    if (lastResult.style != "loginsFooter") {
      return;
    }

    // The comment field of `loginsFooter` results have many additional pieces of
    // information for telemetry purposes. After bug 1555209, this information
    // can be passed to the parent process outside of nsIAutoCompleteResult APIs
    // so we won't need this hack.
    let rawExtraData = JSON.parse(lastResult.comment);
    if (!rawExtraData.searchStartTimeMS) {
      throw new Error("Invalid autocomplete search start time");
    }

    if (rawExtraData.stringLength > 1) {
      // To reduce event volume, only record for lengths 0 and 1.
      return;
    }

    let duration =
      Services.telemetry.msSystemNow() - rawExtraData.searchStartTimeMS;
    delete rawExtraData.searchStartTimeMS;

    delete rawExtraData.formHostname;

    // Add counts by result style to rawExtraData.
    results.reduce((accumulated, r) => {
      // Keys can be a maximum of 15 characters and values must be strings.
      let truncatedStyle = r.style.substring(0, 15);
      accumulated[truncatedStyle] = (accumulated[truncatedStyle] || 0) + 1;
      return accumulated;
    }, rawExtraData);

    // Convert extra values to strings since recordEvent requires that.
    let extraStrings = Object.fromEntries(
      Object.entries(rawExtraData).map(([key, val]) => {
        let stringVal = "";
        if (typeof val == "boolean") {
          stringVal += val ? "1" : "0";
        } else {
          stringVal += val;
        }
        return [key, stringVal];
      })
    );

    Services.telemetry.recordEvent(
      "form_autocomplete",
      "show",
      "logins",
      // Convert to a string
      duration + "",
      extraStrings
    );
  }

  invalidate(results) {
    if (!this.openedPopup) {
      return;
    }

    if (!results.length) {
      this.closePopup();
    } else {
      AutoCompleteResultView.setResults(this, results);
      this.openedPopup.invalidate();
      this._maybeRecordTelemetryEvents(results);
    }
  }

  closePopup() {
    if (this.openedPopup) {
      // Note that hidePopup() closes the popup immediately,
      // so popuphiding or popuphidden events will be fired
      // and handled during this call.
      this.openedPopup.hidePopup();
    }
  }

  receiveMessage(message) {
    let browser = this.browsingContext.top.embedderElement;
    if (!browser || !browser.autoCompletePopup) {
      // If there is no browser or popup, just make sure that the popup has been closed.
      if (this.openedPopup) {
        this.openedPopup.closePopup();
      }

      // Returning false to pacify ESLint, but this return value is
      // ignored by the messaging infrastructure.
      return false;
    }

    switch (message.name) {
      case "FormAutoComplete:SetSelectedIndex": {
        let { index } = message.data;
        if (this.openedPopup) {
          this.openedPopup.selectedIndex = index;
        }
        break;
      }

      case "FormAutoComplete:MaybeOpenPopup": {
        let { results, rect, dir } = message.data;
        this.showPopupWithResults({
          rect,
          dir,
          results,
        });

        this.notifyListeners();
        break;
      }

      case "FormAutoComplete:Invalidate": {
        let { results } = message.data;
        this.invalidate(results);
        break;
      }

      case "FormAutoComplete:ClosePopup": {
        this.closePopup();
        break;
      }

      case "FormAutoComplete:Disconnect": {
        // The controller stopped controlling the current input, so clear
        // any cached data.  This is necessary cause otherwise we'd clear data
        // only when starting a new search, but the next input could not support
        // autocomplete and it would end up inheriting the existing data.
        AutoCompleteResultView.clearResults();
        break;
      }
    }
    // Returning false to pacify ESLint, but this return value is
    // ignored by the messaging infrastructure.
    return false;
  }

  notifyListeners() {
    let window = this.browsingContext.top.embedderElement.ownerGlobal;
    for (let listener of autoCompleteListeners) {
      try {
        listener(window);
      } catch (ex) {
        Cu.reportError(ex);
      }
    }
  }

  /**
   * Despite its name, this handleEnter is only called when the user clicks on
   * one of the items in the popup since the popup is rendered in the parent process.
   * The real controller's handleEnter is called directly in the content process
   * for other methods of completing a selection (e.g. using the tab or enter
   * keys) since the field with focus is in that process.
   * @param {boolean} aIsPopupSelection
   */
  handleEnter(aIsPopupSelection) {
    if (this.openedPopup) {
      this.sendAsyncMessage("FormAutoComplete:HandleEnter", {
        selectedIndex: this.openedPopup.selectedIndex,
        isPopupSelection: aIsPopupSelection,
      });
    }
  }

  stopSearch() {}

  /**
   * Sends a message to the browser that is requesting the input
   * that the open popup should be focused.
   */
  requestFocus() {
    // Bug 1582722 - See the response in AutoCompleteChild.jsm for why this disabled.
    /*
    if (this.openedPopup) {
      this.sendAsyncMessage("FormAutoComplete:Focus");
    }
    */
  }
}