// Copyright (c) 2011 by Kris Maglione <maglione.k@gmail.com>
//
// This work is licensed for reuse under an MIT license. Details are
// given in the LICENSE.txt file included with this file.
"use strict";

try {

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

var EXPORTED_SYMBOLS = ["JSMLoader"];

var BOOTSTRAP_CONTRACT = "@dactyl.googlecode.com/base/bootstrap";
var JSMLoader = BOOTSTRAP_CONTRACT in Components.classes &&
    Components.classes[BOOTSTRAP_CONTRACT].getService().wrappedJSObject.loader;

if (!JSMLoader && "@mozilla.org/fuel/application;1" in Components.classes)
    JSMLoader = Components.classes["@mozilla.org/fuel/application;1"]
                          .getService(Components.interfaces.extIApplication)
                          .storage.get("dactyl.JSMLoader", null);

if (JSMLoader && JSMLoader.bump === 5)
    JSMLoader.global = this;
else
    JSMLoader = {
        bump: 5,

        builtin: Cu.Sandbox(this),

        canonical: {},

        factories: [],

        global: this,

        globals: JSMLoader ? JSMLoader.globals : {},

        io: Cc["@mozilla.org/network/io-service;1"].getService(Ci.nsIIOService),

        loader: Cc["@mozilla.org/moz/jssubscript-loader;1"].getService(Ci.mozIJSSubScriptLoader),

        manager: Components.manager.QueryInterface(Ci.nsIComponentRegistrar),

        modules: JSMLoader && JSMLoader.modules || {},

        stale: JSMLoader ? JSMLoader.stale : {},

        suffix: "",

        times: {
            all: 0,
            add: function add(major, minor, delta) {
                this.all += delta;

                this[major] = (this[major] || 0) + delta;
                if (minor) {
                    minor = ":" + minor;
                    this[minor] = (this[minor] || 0) + delta;
                    this[major + minor] = (this[major + minor] || 0) + delta;
                }
            },
            clear: function clear() {
                for (let key in this)
                    if (typeof this[key] !== "number")
                        delete this[key];
            }
        },

        init: function init(suffix) {
            this.initialized = true;
            this.suffix = suffix || "";

            let base = this.load("base.jsm", this.global);
            this.global.EXPORTED_SYMBOLS = base.EXPORTED_SYMBOLS;
            this.global.JSMLoader = this;
            base.JSMLoader = this;
        },

        getTarget: function getTarget(url) {
            if (url.indexOf(":") === -1)
                url = "resource://dactyl" + this.suffix + "/" + url;

            let chan = this.io.newChannel(url, null, null);
            chan.cancel(Cr.NS_BINDING_ABORTED);
            return chan.name;
        },

        load: function load(name, target) {
            let url = name;
            if (url.indexOf(":") === -1)
                url = "resource://dactyl" + this.suffix + "/" + url;
            let targetURL = this.getTarget(url);

            let stale = this.stale[name] || this.stale[targetURL];
            if (stale) {
                delete this.stale[name];
                delete this.stale[targetURL];

                let loadURL = url.replace(RegExp("^(resource://dactyl)/"), "$1" + this.suffix + "/");

                let global = this.globals[name];
                if (stale === targetURL)
                    this.loadSubScript(loadURL, global.global || global);
            }

            try {
                let now = Date.now();
                this.modules[url] = true;
                let global = Cu.import(url, target);

                if (!(name in this.globals))
                    this.times.add("require", name, Date.now() - now);

                return this.globals[name] = global;
            }
            catch (e) {
                dump("Importing " + url + ": " + e + "\n" + (e.stack || Error().stack));
                throw e;
            }
        },

        loadSubScript: function loadSubScript(script) {
            let now = Date.now();
            this.loader.loadSubScript.apply(this.loader, arguments);
            this.times.add("loadSubScript", script, Date.now() - now);
        },

        cleanup: function unregister() {
            for each (let factory in this.factories.splice(0))
                this.manager.unregisterFactory(factory.classID, factory);
        },

        purge: function purge() {
            dump("dactyl: JSMLoader: purge\n");

            if (Cu.unload) {
                Object.keys(this.modules).reverse().forEach(function (url) {
                    try {
                        Cu.unload(url);
                    }
                    catch (e) {
                        Cu.reportError(e);
                    }
                });
            }
            else {
                for (let [url, global] in Iterator(this.globals)) {
                    if (url === "bootstrap.jsm" || url === "resource://dactyl/bootstrap.jsm")
                        continue;

                    let target = this.getTarget(url);
                    this.stale[url] = target;
                    this.stale[target] = target;

                    for each (let prop in Object.getOwnPropertyNames(global))
                        try {
                            if (!(prop in this.builtin) &&
                                ["JSMLoader", "Set", "set", "EXPORTED_SYMBOLS"].indexOf(prop) < 0 &&
                                !global.__lookupGetter__(prop))
                                global[prop] = undefined;
                        }
                        catch (e) {
                            dump("Deleting property " + prop + " on " + url + ":\n    " + e + "\n");
                            Cu.reportError(e);
                        }
                }
            }
        },

        registerFactory: function registerFactory(factory) {
            this.manager.registerFactory(factory.classID,
                                         String(factory.classID),
                                         factory.contractID,
                                         factory);
            this.factories.push(factory);
        }
    };

}catch(e){ dump(e + "\n" + (e.stack || Error().stack)); Components.utils.reportError(e) }

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