/* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* vim: set sts=2 sw=2 et tw=80: */
"use strict";

/* global getDeveloperToolboxForContext, getLocalTabTargetForContext */

const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;

Cu.import("resource://gre/modules/ExtensionUtils.jsm");

const {SingletonEventManager} = ExtensionUtils;

// Map[context => observer]
let observerMap = new Map();

function getObserver(context) {
  let _observer = observerMap.get(context);
  if (!_observer) {
    _observer = {
      onNavigated: function(event, data) {
        if (event == "tabNavigated" && data.state == "stop") {
          this.emit("navigated", {url: data.url});
        }
      },
    };
    EventEmitter.decorate(_observer);
    const toolbox = getDeveloperToolboxForContext(context);
    if (!toolbox || !toolbox.target.isLocalTab) {
      throw new Error("unable to subscribe to the tabNavigated event for the current inspected tab");
    }
    getLocalTabTargetForContext(context, toolbox.target).then(clonedTarget => {
      clonedTarget.client.addListener("tabNavigated", _observer.onNavigated)
      observerMap.set(context, _observer);
    });
  }
  return _observer;
}
extensions.registerSchemaAPI("devtools.network", "devtools_parent", (context) => {
  return {
    devtools: {
      network: {
        onNavigated: new SingletonEventManager(context, "devtools.onNavigated", fire => {
          let listener = (event, data) => {
            context.runSafe(fire, data);
          };

          getObserver(context).on("navigated", listener);
          return () => {
            getObserver(context).off("navigated", listener);
          };
        }).api(),
      },
    },
  };
});