/* 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/. */

const DEBUG = false;
function debug(s) {
  dump("-*- NotificationStorage.js: " + s + "\n");
}

const kMessageNotificationGetAllOk = "Notification:GetAll:Return:OK";
const kMessageNotificationGetAllKo = "Notification:GetAll:Return:KO";
const kMessageNotificationSaveKo = "Notification:Save:Return:KO";
const kMessageNotificationDeleteKo = "Notification:Delete:Return:KO";

const kMessages = [
  kMessageNotificationGetAllOk,
  kMessageNotificationGetAllKo,
  kMessageNotificationSaveKo,
  kMessageNotificationDeleteKo,
];

export function NotificationStorage() {
  this._requests = {};
  this._requestCount = 0;

  Services.obs.addObserver(this, "xpcom-shutdown");

  // Register for message listeners.
  this.registerListeners();
}

NotificationStorage.prototype = {
  registerListeners() {
    for (let message of kMessages) {
      Services.cpmm.addMessageListener(message, this);
    }
  },

  unregisterListeners() {
    for (let message of kMessages) {
      Services.cpmm.removeMessageListener(message, this);
    }
  },

  observe(aSubject, aTopic, aData) {
    if (DEBUG) {
      debug("Topic: " + aTopic);
    }
    if (aTopic === "xpcom-shutdown") {
      Services.obs.removeObserver(this, "xpcom-shutdown");
      this.unregisterListeners();
    }
  },

  put(
    origin,
    id,
    title,
    dir,
    lang,
    body,
    tag,
    icon,
    alertName,
    data,
    behavior,
    serviceWorkerRegistrationScope
  ) {
    if (DEBUG) {
      debug("PUT: " + origin + " " + id + ": " + title);
    }
    var notification = {
      id,
      title,
      dir,
      lang,
      body,
      tag,
      icon,
      alertName,
      timestamp: new Date().getTime(),
      origin,
      data,
      mozbehavior: behavior,
      serviceWorkerRegistrationScope,
    };

    Services.cpmm.sendAsyncMessage("Notification:Save", {
      origin,
      notification,
    });
  },

  get(origin, tag, callback) {
    if (DEBUG) {
      debug("GET: " + origin + " " + tag);
    }
    this._fetchFromDB(origin, tag, callback);
  },

  getByID(origin, id, callback) {
    if (DEBUG) {
      debug("GETBYID: " + origin + " " + id);
    }
    var GetByIDProxyCallback = function (id, originalCallback) {
      this.searchID = id;
      this.originalCallback = originalCallback;
      var self = this;
      this.handle = function (
        id,
        title,
        dir,
        lang,
        body,
        tag,
        icon,
        data,
        behavior,
        serviceWorkerRegistrationScope
      ) {
        if (id == this.searchID) {
          self.originalCallback.handle(
            id,
            title,
            dir,
            lang,
            body,
            tag,
            icon,
            data,
            behavior,
            serviceWorkerRegistrationScope
          );
        }
      };
      this.done = function () {
        self.originalCallback.done();
      };
    };

    return this.get(origin, "", new GetByIDProxyCallback(id, callback));
  },

  delete(origin, id) {
    if (DEBUG) {
      debug("DELETE: " + id);
    }
    Services.cpmm.sendAsyncMessage("Notification:Delete", {
      origin,
      id,
    });
  },

  receiveMessage(message) {
    var request = this._requests[message.data.requestID];

    switch (message.name) {
      case kMessageNotificationGetAllOk:
        delete this._requests[message.data.requestID];
        this._returnNotifications(
          message.data.notifications,
          request.origin,
          request.tag,
          request.callback
        );
        break;

      case kMessageNotificationGetAllKo:
        delete this._requests[message.data.requestID];
        try {
          request.callback.done();
        } catch (e) {
          debug("Error calling callback done: " + e);
        }
        break;
      case kMessageNotificationSaveKo:
      case kMessageNotificationDeleteKo:
        if (DEBUG) {
          debug(
            "Error received when treating: '" +
              message.name +
              "': " +
              message.data.errorMsg
          );
        }
        break;

      default:
        if (DEBUG) {
          debug("Unrecognized message: " + message.name);
        }
        break;
    }
  },

  _fetchFromDB(origin, tag, callback) {
    var request = {
      origin,
      tag,
      callback,
    };
    var requestID = this._requestCount++;
    this._requests[requestID] = request;
    Services.cpmm.sendAsyncMessage("Notification:GetAll", {
      origin,
      tag,
      requestID,
    });
  },

  _returnNotifications(notifications, origin, tag, callback) {
    // Pass each notification back separately.
    // The callback is called asynchronously to match the behaviour when
    // fetching from the database.
    notifications.forEach(function (notification) {
      try {
        Services.tm.dispatchToMainThread(
          callback.handle.bind(
            callback,
            notification.id,
            notification.title,
            notification.dir,
            notification.lang,
            notification.body,
            notification.tag,
            notification.icon,
            notification.data,
            notification.mozbehavior,
            notification.serviceWorkerRegistrationScope
          )
        );
      } catch (e) {
        if (DEBUG) {
          debug("Error calling callback handle: " + e);
        }
      }
    });
    try {
      Services.tm.dispatchToMainThread(callback.done);
    } catch (e) {
      if (DEBUG) {
        debug("Error calling callback done: " + e);
      }
    }
  },

  QueryInterface: ChromeUtils.generateQI(["nsINotificationStorage"]),
};