components/webcomponentsjs/HTMLImports.js

/**
 * @license
 * Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
 * This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
 * The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
 * The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
 * Code distributed by Google as part of the polymer project is also
 * subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
 */
// @version 0.6.1
if (typeof WeakMap === "undefined") {
  (function() {
    var defineProperty = Object.defineProperty;
    var counter = Date.now() % 1e9;
    var WeakMap = function() {
      this.name = "__st" + (Math.random() * 1e9 >>> 0) + (counter++ + "__");
    };
    WeakMap.prototype = {
      set: function(key, value) {
        var entry = key[this.name];
        if (entry && entry[0] === key) entry[1] = value; else defineProperty(key, this.name, {
          value: [ key, value ],
          writable: true
        });
        return this;
      },
      get: function(key) {
        var entry;
        return (entry = key[this.name]) && entry[0] === key ? entry[1] : undefined;
      },
      "delete": function(key) {
        var entry = key[this.name];
        if (!entry || entry[0] !== key) return false;
        entry[0] = entry[1] = undefined;
        return true;
      },
      has: function(key) {
        var entry = key[this.name];
        if (!entry) return false;
        return entry[0] === key;
      }
    };
    window.WeakMap = WeakMap;
  })();
}

(function(global) {
  var registrationsTable = new WeakMap();
  var setImmediate;
  if (/Trident|Edge/.test(navigator.userAgent)) {
    setImmediate = setTimeout;
  } else if (window.setImmediate) {
    setImmediate = window.setImmediate;
  } else {
    var setImmediateQueue = [];
    var sentinel = String(Math.random());
    window.addEventListener("message", function(e) {
      if (e.data === sentinel) {
        var queue = setImmediateQueue;
        setImmediateQueue = [];
        queue.forEach(function(func) {
          func();
        });
      }
    });
    setImmediate = function(func) {
      setImmediateQueue.push(func);
      window.postMessage(sentinel, "*");
    };
  }
  var isScheduled = false;
  var scheduledObservers = [];
  function scheduleCallback(observer) {
    scheduledObservers.push(observer);
    if (!isScheduled) {
      isScheduled = true;
      setImmediate(dispatchCallbacks);
    }
  }
  function wrapIfNeeded(node) {
    return window.ShadowDOMPolyfill && window.ShadowDOMPolyfill.wrapIfNeeded(node) || node;
  }
  function dispatchCallbacks() {
    isScheduled = false;
    var observers = scheduledObservers;
    scheduledObservers = [];
    observers.sort(function(o1, o2) {
      return o1.uid_ - o2.uid_;
    });
    var anyNonEmpty = false;
    observers.forEach(function(observer) {
      var queue = observer.takeRecords();
      removeTransientObserversFor(observer);
      if (queue.length) {
        observer.callback_(queue, observer);
        anyNonEmpty = true;
      }
    });
    if (anyNonEmpty) dispatchCallbacks();
  }
  function removeTransientObserversFor(observer) {
    observer.nodes_.forEach(function(node) {
      var registrations = registrationsTable.get(node);
      if (!registrations) return;
      registrations.forEach(function(registration) {
        if (registration.observer === observer) registration.removeTransientObservers();
      });
    });
  }
  function forEachAncestorAndObserverEnqueueRecord(target, callback) {
    for (var node = target; node; node = node.parentNode) {
      var registrations = registrationsTable.get(node);
      if (registrations) {
        for (var j = 0; j < registrations.length; j++) {
          var registration = registrations[j];
          var options = registration.options;
          if (node !== target && !options.subtree) continue;
          var record = callback(options);
          if (record) registration.enqueue(record);
        }
      }
    }
  }
  var uidCounter = 0;
  function JsMutationObserver(callback) {
    this.callback_ = callback;
    this.nodes_ = [];
    this.records_ = [];
    this.uid_ = ++uidCounter;
  }
  JsMutationObserver.prototype = {
    observe: function(target, options) {
      target = wrapIfNeeded(target);
      if (!options.childList && !options.attributes && !options.characterData || options.attributeOldValue && !options.attributes || options.attributeFilter && options.attributeFilter.length && !options.attributes || options.characterDataOldValue && !options.characterData) {
        throw new SyntaxError();
      }
      var registrations = registrationsTable.get(target);
      if (!registrations) registrationsTable.set(target, registrations = []);
      var registration;
      for (var i = 0; i < registrations.length; i++) {
        if (registrations[i].observer === this) {
          registration = registrations[i];
          registration.removeListeners();
          registration.options = options;
          break;
        }
      }
      if (!registration) {
        registration = new Registration(this, target, options);
        registrations.push(registration);
        this.nodes_.push(target);
      }
      registration.addListeners();
    },
    disconnect: function() {
      this.nodes_.forEach(function(node) {
        var registrations = registrationsTable.get(node);
        for (var i = 0; i < registrations.length; i++) {
          var registration = registrations[i];
          if (registration.observer === this) {
            registration.removeListeners();
            registrations.splice(i, 1);
            break;
          }
        }
      }, this);
      this.records_ = [];
    },
    takeRecords: function() {
      var copyOfRecords = this.records_;
      this.records_ = [];
      return copyOfRecords;
    }
  };
  function MutationRecord(type, target) {
    this.type = type;
    this.target = target;
    this.addedNodes = [];
    this.removedNodes = [];
    this.previousSibling = null;
    this.nextSibling = null;
    this.attributeName = null;
    this.attributeNamespace = null;
    this.oldValue = null;
  }
  function copyMutationRecord(original) {
    var record = new MutationRecord(original.type, original.target);
    record.addedNodes = original.addedNodes.slice();
    record.removedNodes = original.removedNodes.slice();
    record.previousSibling = original.previousSibling;
    record.nextSibling = original.nextSibling;
    record.attributeName = original.attributeName;
    record.attributeNamespace = original.attributeNamespace;
    record.oldValue = original.oldValue;
    return record;
  }
  var currentRecord, recordWithOldValue;
  function getRecord(type, target) {
    return currentRecord = new MutationRecord(type, target);
  }
  function getRecordWithOldValue(oldValue) {
    if (recordWithOldValue) return recordWithOldValue;
    recordWithOldValue = copyMutationRecord(currentRecord);
    recordWithOldValue.oldValue = oldValue;
    return recordWithOldValue;
  }
  function clearRecords() {
    currentRecord = recordWithOldValue = undefined;
  }
  function recordRepresentsCurrentMutation(record) {
    return record === recordWithOldValue || record === currentRecord;
  }
  function selectRecord(lastRecord, newRecord) {
    if (lastRecord === newRecord) return lastRecord;
    if (recordWithOldValue && recordRepresentsCurrentMutation(lastRecord)) return recordWithOldValue;
    return null;
  }
  function Registration(observer, target, options) {
    this.observer = observer;
    this.target = target;
    this.options = options;
    this.transientObservedNodes = [];
  }
  Registration.prototype = {
    enqueue: function(record) {
      var records = this.observer.records_;
      var length = records.length;
      if (records.length > 0) {
        var lastRecord = records[length - 1];
        var recordToReplaceLast = selectRecord(lastRecord, record);
        if (recordToReplaceLast) {
          records[length - 1] = recordToReplaceLast;
          return;
        }
      } else {
        scheduleCallback(this.observer);
      }
      records[length] = record;
    },
    addListeners: function() {
      this.addListeners_(this.target);
    },
    addListeners_: function(node) {
      var options = this.options;
      if (options.attributes) node.addEventListener("DOMAttrModified", this, true);
      if (options.characterData) node.addEventListener("DOMCharacterDataModified", this, true);
      if (options.childList) node.addEventListener("DOMNodeInserted", this, true);
      if (options.childList || options.subtree) node.addEventListener("DOMNodeRemoved", this, true);
    },
    removeListeners: function() {
      this.removeListeners_(this.target);
    },
    removeListeners_: function(node) {
      var options = this.options;
      if (options.attributes) node.removeEventListener("DOMAttrModified", this, true);
      if (options.characterData) node.removeEventListener("DOMCharacterDataModified", this, true);
      if (options.childList) node.removeEventListener("DOMNodeInserted", this, true);
      if (options.childList || options.subtree) node.removeEventListener("DOMNodeRemoved", this, true);
    },
    addTransientObserver: function(node) {
      if (node === this.target) return;
      this.addListeners_(node);
      this.transientObservedNodes.push(node);
      var registrations = registrationsTable.get(node);
      if (!registrations) registrationsTable.set(node, registrations = []);
      registrations.push(this);
    },
    removeTransientObservers: function() {
      var transientObservedNodes = this.transientObservedNodes;
      this.transientObservedNodes = [];
      transientObservedNodes.forEach(function(node) {
        this.removeListeners_(node);
        var registrations = registrationsTable.get(node);
        for (var i = 0; i < registrations.length; i++) {
          if (registrations[i] === this) {
            registrations.splice(i, 1);
            break;
          }
        }
      }, this);
    },
    handleEvent: function(e) {
      e.stopImmediatePropagation();
      switch (e.type) {
       case "DOMAttrModified":
        var name = e.attrName;
        var namespace = e.relatedNode.namespaceURI;
        var target = e.target;
        var record = new getRecord("attributes", target);
        record.attributeName = name;
        record.attributeNamespace = namespace;
        var oldValue = e.attrChange === MutationEvent.ADDITION ? null : e.prevValue;
        forEachAncestorAndObserverEnqueueRecord(target, function(options) {
          if (!options.attributes) return;
          if (options.attributeFilter && options.attributeFilter.length && options.attributeFilter.indexOf(name) === -1 && options.attributeFilter.indexOf(namespace) === -1) {
            return;
          }
          if (options.attributeOldValue) return getRecordWithOldValue(oldValue);
          return record;
        });
        break;

       case "DOMCharacterDataModified":
        var target = e.target;
        var record = getRecord("characterData", target);
        var oldValue = e.prevValue;
        forEachAncestorAndObserverEnqueueRecord(target, function(options) {
          if (!options.characterData) return;
          if (options.characterDataOldValue) return getRecordWithOldValue(oldValue);
          return record;
        });
        break;

       case "DOMNodeRemoved":
        this.addTransientObserver(e.target);

       case "DOMNodeInserted":
        var changedNode = e.target;
        var addedNodes, removedNodes;
        if (e.type === "DOMNodeInserted") {
          addedNodes = [ changedNode ];
          removedNodes = [];
        } else {
          addedNodes = [];
          removedNodes = [ changedNode ];
        }
        var previousSibling = changedNode.previousSibling;
        var nextSibling = changedNode.nextSibling;
        var record = getRecord("childList", e.target.parentNode);
        record.addedNodes = addedNodes;
        record.removedNodes = removedNodes;
        record.previousSibling = previousSibling;
        record.nextSibling = nextSibling;
        forEachAncestorAndObserverEnqueueRecord(e.relatedNode, function(options) {
          if (!options.childList) return;
          return record;
        });
      }
      clearRecords();
    }
  };
  global.JsMutationObserver = JsMutationObserver;
  if (!global.MutationObserver) global.MutationObserver = JsMutationObserver;
})(this);

window.HTMLImports = window.HTMLImports || {
  flags: {}
};

(function(scope) {
  var IMPORT_LINK_TYPE = "import";
  var useNative = Boolean(IMPORT_LINK_TYPE in document.createElement("link"));
  var hasShadowDOMPolyfill = Boolean(window.ShadowDOMPolyfill);
  var wrap = function(node) {
    return hasShadowDOMPolyfill ? ShadowDOMPolyfill.wrapIfNeeded(node) : node;
  };
  var rootDocument = wrap(document);
  var currentScriptDescriptor = {
    get: function() {
      var script = HTMLImports.currentScript || document.currentScript || (document.readyState !== "complete" ? document.scripts[document.scripts.length - 1] : null);
      return wrap(script);
    },
    configurable: true
  };
  Object.defineProperty(document, "_currentScript", currentScriptDescriptor);
  Object.defineProperty(rootDocument, "_currentScript", currentScriptDescriptor);
  var isIE = /Trident|Edge/.test(navigator.userAgent);
  function whenReady(callback, doc) {
    doc = doc || rootDocument;
    whenDocumentReady(function() {
      watchImportsLoad(callback, doc);
    }, doc);
  }
  var requiredReadyState = isIE ? "complete" : "interactive";
  var READY_EVENT = "readystatechange";
  function isDocumentReady(doc) {
    return doc.readyState === "complete" || doc.readyState === requiredReadyState;
  }
  function whenDocumentReady(callback, doc) {
    if (!isDocumentReady(doc)) {
      var checkReady = function() {
        if (doc.readyState === "complete" || doc.readyState === requiredReadyState) {
          doc.removeEventListener(READY_EVENT, checkReady);
          whenDocumentReady(callback, doc);
        }
      };
      doc.addEventListener(READY_EVENT, checkReady);
    } else if (callback) {
      callback();
    }
  }
  function markTargetLoaded(event) {
    event.target.__loaded = true;
  }
  function watchImportsLoad(callback, doc) {
    var imports = doc.querySelectorAll("link[rel=import]");
    var parsedCount = 0, importCount = imports.length, newImports = [], errorImports = [];
    function checkDone() {
      if (parsedCount == importCount && callback) {
        callback({
          allImports: imports,
          loadedImports: newImports,
          errorImports: errorImports
        });
      }
    }
    function loadedImport(e) {
      markTargetLoaded(e);
      newImports.push(this);
      parsedCount++;
      checkDone();
    }
    function errorLoadingImport(e) {
      errorImports.push(this);
      parsedCount++;
      checkDone();
    }
    if (importCount) {
      for (var i = 0, imp; i < importCount && (imp = imports[i]); i++) {
        if (isImportLoaded(imp)) {
          parsedCount++;
          checkDone();
        } else {
          imp.addEventListener("load", loadedImport);
          imp.addEventListener("error", errorLoadingImport);
        }
      }
    } else {
      checkDone();
    }
  }
  function isImportLoaded(link) {
    return useNative ? link.__loaded || link.import && link.import.readyState !== "loading" : link.__importParsed;
  }
  if (useNative) {
    new MutationObserver(function(mxns) {
      for (var i = 0, l = mxns.length, m; i < l && (m = mxns[i]); i++) {
        if (m.addedNodes) {
          handleImports(m.addedNodes);
        }
      }
    }).observe(document.head, {
      childList: true
    });
    function handleImports(nodes) {
      for (var i = 0, l = nodes.length, n; i < l && (n = nodes[i]); i++) {
        if (isImport(n)) {
          handleImport(n);
        }
      }
    }
    function isImport(element) {
      return element.localName === "link" && element.rel === "import";
    }
    function handleImport(element) {
      var loaded = element.import;
      if (loaded) {
        markTargetLoaded({
          target: element
        });
      } else {
        element.addEventListener("load", markTargetLoaded);
        element.addEventListener("error", markTargetLoaded);
      }
    }
    (function() {
      if (document.readyState === "loading") {
        var imports = document.querySelectorAll("link[rel=import]");
        for (var i = 0, l = imports.length, imp; i < l && (imp = imports[i]); i++) {
          handleImport(imp);
        }
      }
    })();
  }
  whenReady(function(detail) {
    HTMLImports.ready = true;
    HTMLImports.readyTime = new Date().getTime();
    var evt = rootDocument.createEvent("CustomEvent");
    evt.initCustomEvent("HTMLImportsLoaded", true, true, detail);
    rootDocument.dispatchEvent(evt);
  });
  scope.IMPORT_LINK_TYPE = IMPORT_LINK_TYPE;
  scope.useNative = useNative;
  scope.rootDocument = rootDocument;
  scope.whenReady = whenReady;
  scope.isIE = isIE;
})(HTMLImports);

(function(scope) {
  var modules = [];
  var addModule = function(module) {
    modules.push(module);
  };
  var initializeModules = function() {
    modules.forEach(function(module) {
      module(scope);
    });
  };
  scope.addModule = addModule;
  scope.initializeModules = initializeModules;
})(HTMLImports);

HTMLImports.addModule(function(scope) {
  var CSS_URL_REGEXP = /(url\()([^)]*)(\))/g;
  var CSS_IMPORT_REGEXP = /(@import[\s]+(?!url\())([^;]*)(;)/g;
  var path = {
    resolveUrlsInStyle: function(style, linkUrl) {
      var doc = style.ownerDocument;
      var resolver = doc.createElement("a");
      style.textContent = this.resolveUrlsInCssText(style.textContent, linkUrl, resolver);
      return style;
    },
    resolveUrlsInCssText: function(cssText, linkUrl, urlObj) {
      var r = this.replaceUrls(cssText, urlObj, linkUrl, CSS_URL_REGEXP);
      r = this.replaceUrls(r, urlObj, linkUrl, CSS_IMPORT_REGEXP);
      return r;
    },
    replaceUrls: function(text, urlObj, linkUrl, regexp) {
      return text.replace(regexp, function(m, pre, url, post) {
        var urlPath = url.replace(/["']/g, "");
        if (linkUrl) {
          urlPath = new URL(urlPath, linkUrl).href;
        }
        urlObj.href = urlPath;
        urlPath = urlObj.href;
        return pre + "'" + urlPath + "'" + post;
      });
    }
  };
  scope.path = path;
});

HTMLImports.addModule(function(scope) {
  var xhr = {
    async: true,
    ok: function(request) {
      return request.status >= 200 && request.status < 300 || request.status === 304 || request.status === 0;
    },
    load: function(url, next, nextContext) {
      var request = new XMLHttpRequest();
      if (scope.flags.debug || scope.flags.bust) {
        url += "?" + Math.random();
      }
      request.open("GET", url, xhr.async);
      request.addEventListener("readystatechange", function(e) {
        if (request.readyState === 4) {
          var locationHeader = request.getResponseHeader("Location");
          var redirectedUrl = null;
          if (locationHeader) {
            var redirectedUrl = locationHeader.substr(0, 1) === "/" ? location.origin + locationHeader : locationHeader;
          }
          next.call(nextContext, !xhr.ok(request) && request, request.response || request.responseText, redirectedUrl);
        }
      });
      request.send();
      return request;
    },
    loadDocument: function(url, next, nextContext) {
      this.load(url, next, nextContext).responseType = "document";
    }
  };
  scope.xhr = xhr;
});

HTMLImports.addModule(function(scope) {
  var xhr = scope.xhr;
  var flags = scope.flags;
  var Loader = function(onLoad, onComplete) {
    this.cache = {};
    this.onload = onLoad;
    this.oncomplete = onComplete;
    this.inflight = 0;
    this.pending = {};
  };
  Loader.prototype = {
    addNodes: function(nodes) {
      this.inflight += nodes.length;
      for (var i = 0, l = nodes.length, n; i < l && (n = nodes[i]); i++) {
        this.require(n);
      }
      this.checkDone();
    },
    addNode: function(node) {
      this.inflight++;
      this.require(node);
      this.checkDone();
    },
    require: function(elt) {
      var url = elt.src || elt.href;
      elt.__nodeUrl = url;
      if (!this.dedupe(url, elt)) {
        this.fetch(url, elt);
      }
    },
    dedupe: function(url, elt) {
      if (this.pending[url]) {
        this.pending[url].push(elt);
        return true;
      }
      var resource;
      if (this.cache[url]) {
        this.onload(url, elt, this.cache[url]);
        this.tail();
        return true;
      }
      this.pending[url] = [ elt ];
      return false;
    },
    fetch: function(url, elt) {
      flags.load && console.log("fetch", url, elt);
      if (!url) {
        setTimeout(function() {
          this.receive(url, elt, {
            error: "href must be specified"
          }, null);
        }.bind(this), 0);
      } else if (url.match(/^data:/)) {
        var pieces = url.split(",");
        var header = pieces[0];
        var body = pieces[1];
        if (header.indexOf(";base64") > -1) {
          body = atob(body);
        } else {
          body = decodeURIComponent(body);
        }
        setTimeout(function() {
          this.receive(url, elt, null, body);
        }.bind(this), 0);
      } else {
        var receiveXhr = function(err, resource, redirectedUrl) {
          this.receive(url, elt, err, resource, redirectedUrl);
        }.bind(this);
        xhr.load(url, receiveXhr);
      }
    },
    receive: function(url, elt, err, resource, redirectedUrl) {
      this.cache[url] = resource;
      var $p = this.pending[url];
      for (var i = 0, l = $p.length, p; i < l && (p = $p[i]); i++) {
        this.onload(url, p, resource, err, redirectedUrl);
        this.tail();
      }
      this.pending[url] = null;
    },
    tail: function() {
      --this.inflight;
      this.checkDone();
    },
    checkDone: function() {
      if (!this.inflight) {
        this.oncomplete();
      }
    }
  };
  scope.Loader = Loader;
});

HTMLImports.addModule(function(scope) {
  var Observer = function(addCallback) {
    this.addCallback = addCallback;
    this.mo = new MutationObserver(this.handler.bind(this));
  };
  Observer.prototype = {
    handler: function(mutations) {
      for (var i = 0, l = mutations.length, m; i < l && (m = mutations[i]); i++) {
        if (m.type === "childList" && m.addedNodes.length) {
          this.addedNodes(m.addedNodes);
        }
      }
    },
    addedNodes: function(nodes) {
      if (this.addCallback) {
        this.addCallback(nodes);
      }
      for (var i = 0, l = nodes.length, n, loading; i < l && (n = nodes[i]); i++) {
        if (n.children && n.children.length) {
          this.addedNodes(n.children);
        }
      }
    },
    observe: function(root) {
      this.mo.observe(root, {
        childList: true,
        subtree: true
      });
    }
  };
  scope.Observer = Observer;
});

HTMLImports.addModule(function(scope) {
  var path = scope.path;
  var rootDocument = scope.rootDocument;
  var flags = scope.flags;
  var isIE = scope.isIE;
  var IMPORT_LINK_TYPE = scope.IMPORT_LINK_TYPE;
  var IMPORT_SELECTOR = "link[rel=" + IMPORT_LINK_TYPE + "]";
  var importParser = {
    documentSelectors: IMPORT_SELECTOR,
    importsSelectors: [ IMPORT_SELECTOR, "link[rel=stylesheet]", "style", "script:not([type])", 'script[type="text/javascript"]' ].join(","),
    map: {
      link: "parseLink",
      script: "parseScript",
      style: "parseStyle"
    },
    dynamicElements: [],
    parseNext: function() {
      var next = this.nextToParse();
      if (next) {
        this.parse(next);
      }
    },
    parse: function(elt) {
      if (this.isParsed(elt)) {
        flags.parse && console.log("[%s] is already parsed", elt.localName);
        return;
      }
      var fn = this[this.map[elt.localName]];
      if (fn) {
        this.markParsing(elt);
        fn.call(this, elt);
      }
    },
    parseDynamic: function(elt, quiet) {
      this.dynamicElements.push(elt);
      if (!quiet) {
        this.parseNext();
      }
    },
    markParsing: function(elt) {
      flags.parse && console.log("parsing", elt);
      this.parsingElement = elt;
    },
    markParsingComplete: function(elt) {
      elt.__importParsed = true;
      this.markDynamicParsingComplete(elt);
      if (elt.__importElement) {
        elt.__importElement.__importParsed = true;
        this.markDynamicParsingComplete(elt.__importElement);
      }
      this.parsingElement = null;
      flags.parse && console.log("completed", elt);
    },
    markDynamicParsingComplete: function(elt) {
      var i = this.dynamicElements.indexOf(elt);
      if (i >= 0) {
        this.dynamicElements.splice(i, 1);
      }
    },
    parseImport: function(elt) {
      if (HTMLImports.__importsParsingHook) {
        HTMLImports.__importsParsingHook(elt);
      }
      if (elt.import) {
        elt.import.__importParsed = true;
      }
      this.markParsingComplete(elt);
      if (elt.__resource && !elt.__error) {
        elt.dispatchEvent(new CustomEvent("load", {
          bubbles: false
        }));
      } else {
        elt.dispatchEvent(new CustomEvent("error", {
          bubbles: false
        }));
      }
      if (elt.__pending) {
        var fn;
        while (elt.__pending.length) {
          fn = elt.__pending.shift();
          if (fn) {
            fn({
              target: elt
            });
          }
        }
      }
      this.parseNext();
    },
    parseLink: function(linkElt) {
      if (nodeIsImport(linkElt)) {
        this.parseImport(linkElt);
      } else {
        linkElt.href = linkElt.href;
        this.parseGeneric(linkElt);
      }
    },
    parseStyle: function(elt) {
      var src = elt;
      elt = cloneStyle(elt);
      src.__appliedElement = elt;
      elt.__importElement = src;
      this.parseGeneric(elt);
    },
    parseGeneric: function(elt) {
      this.trackElement(elt);
      this.addElementToDocument(elt);
    },
    rootImportForElement: function(elt) {
      var n = elt;
      while (n.ownerDocument.__importLink) {
        n = n.ownerDocument.__importLink;
      }
      return n;
    },
    addElementToDocument: function(elt) {
      var port = this.rootImportForElement(elt.__importElement || elt);
      port.parentNode.insertBefore(elt, port);
    },
    trackElement: function(elt, callback) {
      var self = this;
      var done = function(e) {
        if (callback) {
          callback(e);
        }
        self.markParsingComplete(elt);
        self.parseNext();
      };
      elt.addEventListener("load", done);
      elt.addEventListener("error", done);
      if (isIE && elt.localName === "style") {
        var fakeLoad = false;
        if (elt.textContent.indexOf("@import") == -1) {
          fakeLoad = true;
        } else if (elt.sheet) {
          fakeLoad = true;
          var csr = elt.sheet.cssRules;
          var len = csr ? csr.length : 0;
          for (var i = 0, r; i < len && (r = csr[i]); i++) {
            if (r.type === CSSRule.IMPORT_RULE) {
              fakeLoad = fakeLoad && Boolean(r.styleSheet);
            }
          }
        }
        if (fakeLoad) {
          elt.dispatchEvent(new CustomEvent("load", {
            bubbles: false
          }));
        }
      }
    },
    parseScript: function(scriptElt) {
      var script = document.createElement("script");
      script.__importElement = scriptElt;
      script.src = scriptElt.src ? scriptElt.src : generateScriptDataUrl(scriptElt);
      scope.currentScript = scriptElt;
      this.trackElement(script, function(e) {
        script.parentNode.removeChild(script);
        scope.currentScript = null;
      });
      this.addElementToDocument(script);
    },
    nextToParse: function() {
      this._mayParse = [];
      return !this.parsingElement && (this.nextToParseInDoc(rootDocument) || this.nextToParseDynamic());
    },
    nextToParseInDoc: function(doc, link) {
      if (doc && this._mayParse.indexOf(doc) < 0) {
        this._mayParse.push(doc);
        var nodes = doc.querySelectorAll(this.parseSelectorsForNode(doc));
        for (var i = 0, l = nodes.length, p = 0, n; i < l && (n = nodes[i]); i++) {
          if (!this.isParsed(n)) {
            if (this.hasResource(n)) {
              return nodeIsImport(n) ? this.nextToParseInDoc(n.import, n) : n;
            } else {
              return;
            }
          }
        }
      }
      return link;
    },
    nextToParseDynamic: function() {
      return this.dynamicElements[0];
    },
    parseSelectorsForNode: function(node) {
      var doc = node.ownerDocument || node;
      return doc === rootDocument ? this.documentSelectors : this.importsSelectors;
    },
    isParsed: function(node) {
      return node.__importParsed;
    },
    needsDynamicParsing: function(elt) {
      return this.dynamicElements.indexOf(elt) >= 0;
    },
    hasResource: function(node) {
      if (nodeIsImport(node) && node.import === undefined) {
        return false;
      }
      return true;
    }
  };
  function nodeIsImport(elt) {
    return elt.localName === "link" && elt.rel === IMPORT_LINK_TYPE;
  }
  function generateScriptDataUrl(script) {
    var scriptContent = generateScriptContent(script);
    return "data:text/javascript;charset=utf-8," + encodeURIComponent(scriptContent);
  }
  function generateScriptContent(script) {
    return script.textContent + generateSourceMapHint(script);
  }
  function generateSourceMapHint(script) {
    var owner = script.ownerDocument;
    owner.__importedScripts = owner.__importedScripts || 0;
    var moniker = script.ownerDocument.baseURI;
    var num = owner.__importedScripts ? "-" + owner.__importedScripts : "";
    owner.__importedScripts++;
    return "\n//# sourceURL=" + moniker + num + ".js\n";
  }
  function cloneStyle(style) {
    var clone = style.ownerDocument.createElement("style");
    clone.textContent = style.textContent;
    path.resolveUrlsInStyle(clone);
    return clone;
  }
  scope.parser = importParser;
  scope.IMPORT_SELECTOR = IMPORT_SELECTOR;
});

HTMLImports.addModule(function(scope) {
  var flags = scope.flags;
  var IMPORT_LINK_TYPE = scope.IMPORT_LINK_TYPE;
  var IMPORT_SELECTOR = scope.IMPORT_SELECTOR;
  var rootDocument = scope.rootDocument;
  var Loader = scope.Loader;
  var Observer = scope.Observer;
  var parser = scope.parser;
  var importer = {
    documents: {},
    documentPreloadSelectors: IMPORT_SELECTOR,
    importsPreloadSelectors: [ IMPORT_SELECTOR ].join(","),
    loadNode: function(node) {
      importLoader.addNode(node);
    },
    loadSubtree: function(parent) {
      var nodes = this.marshalNodes(parent);
      importLoader.addNodes(nodes);
    },
    marshalNodes: function(parent) {
      return parent.querySelectorAll(this.loadSelectorsForNode(parent));
    },
    loadSelectorsForNode: function(node) {
      var doc = node.ownerDocument || node;
      return doc === rootDocument ? this.documentPreloadSelectors : this.importsPreloadSelectors;
    },
    loaded: function(url, elt, resource, err, redirectedUrl) {
      flags.load && console.log("loaded", url, elt);
      elt.__resource = resource;
      elt.__error = err;
      if (isImportLink(elt)) {
        var doc = this.documents[url];
        if (doc === undefined) {
          doc = err ? null : makeDocument(resource, redirectedUrl || url);
          if (doc) {
            doc.__importLink = elt;
            this.bootDocument(doc);
          }
          this.documents[url] = doc;
        }
        elt.import = doc;
      }
      parser.parseNext();
    },
    bootDocument: function(doc) {
      this.loadSubtree(doc);
      this.observer.observe(doc);
      parser.parseNext();
    },
    loadedAll: function() {
      parser.parseNext();
    }
  };
  var importLoader = new Loader(importer.loaded.bind(importer), importer.loadedAll.bind(importer));
  importer.observer = new Observer();
  function isImportLink(elt) {
    return isLinkRel(elt, IMPORT_LINK_TYPE);
  }
  function isLinkRel(elt, rel) {
    return elt.localName === "link" && elt.getAttribute("rel") === rel;
  }
  function hasBaseURIAccessor(doc) {
    return !!Object.getOwnPropertyDescriptor(doc, "baseURI");
  }
  function makeDocument(resource, url) {
    var doc = document.implementation.createHTMLDocument(IMPORT_LINK_TYPE);
    doc._URL = url;
    var base = doc.createElement("base");
    base.setAttribute("href", url);
    if (!doc.baseURI && !hasBaseURIAccessor(doc)) {
      Object.defineProperty(doc, "baseURI", {
        value: url
      });
    }
    var meta = doc.createElement("meta");
    meta.setAttribute("charset", "utf-8");
    doc.head.appendChild(meta);
    doc.head.appendChild(base);
    doc.body.innerHTML = resource;
    if (window.HTMLTemplateElement && HTMLTemplateElement.bootstrap) {
      HTMLTemplateElement.bootstrap(doc);
    }
    return doc;
  }
  if (!document.baseURI) {
    var baseURIDescriptor = {
      get: function() {
        var base = document.querySelector("base");
        return base ? base.href : window.location.href;
      },
      configurable: true
    };
    Object.defineProperty(document, "baseURI", baseURIDescriptor);
    Object.defineProperty(rootDocument, "baseURI", baseURIDescriptor);
  }
  scope.importer = importer;
  scope.importLoader = importLoader;
});

HTMLImports.addModule(function(scope) {
  var parser = scope.parser;
  var importer = scope.importer;
  var dynamic = {
    added: function(nodes) {
      var owner, parsed, loading;
      for (var i = 0, l = nodes.length, n; i < l && (n = nodes[i]); i++) {
        if (!owner) {
          owner = n.ownerDocument;
          parsed = parser.isParsed(owner);
        }
        loading = this.shouldLoadNode(n);
        if (loading) {
          importer.loadNode(n);
        }
        if (this.shouldParseNode(n) && parsed) {
          parser.parseDynamic(n, loading);
        }
      }
    },
    shouldLoadNode: function(node) {
      return node.nodeType === 1 && matches.call(node, importer.loadSelectorsForNode(node));
    },
    shouldParseNode: function(node) {
      return node.nodeType === 1 && matches.call(node, parser.parseSelectorsForNode(node));
    }
  };
  importer.observer.addCallback = dynamic.added.bind(dynamic);
  var matches = HTMLElement.prototype.matches || HTMLElement.prototype.matchesSelector || HTMLElement.prototype.webkitMatchesSelector || HTMLElement.prototype.mozMatchesSelector || HTMLElement.prototype.msMatchesSelector;
});

(function(scope) {
  var initializeModules = scope.initializeModules;
  var isIE = scope.isIE;
  if (scope.useNative) {
    return;
  }
  if (isIE && typeof window.CustomEvent !== "function") {
    window.CustomEvent = function(inType, params) {
      params = params || {};
      var e = document.createEvent("CustomEvent");
      e.initCustomEvent(inType, Boolean(params.bubbles), Boolean(params.cancelable), params.detail);
      return e;
    };
    window.CustomEvent.prototype = window.Event.prototype;
  }
  initializeModules();
  var rootDocument = scope.rootDocument;
  function bootstrap() {
    HTMLImports.importer.bootDocument(rootDocument);
  }
  if (document.readyState === "complete" || document.readyState === "interactive" && !window.attachEvent) {
    bootstrap();
  } else {
    document.addEventListener("DOMContentLoaded", bootstrap);
  }
})(HTMLImports);