EPUBJS.Book = function(_url){  
  // Promises
  this.opening = new RSVP.defer();
  this.opened = this.opening.promise;

  this.url = undefined;

  this.spine = undefined;

  this.loading = {
    manifest: new RSVP.defer(),
    spine: new RSVP.defer(),
    metadata: new RSVP.defer(),
    cover: new RSVP.defer(),
    navigation: new RSVP.defer(),
    pageList: new RSVP.defer()
  };

  this.loaded = {
    manifest: this.loading.manifest.promise,
    spine: this.loading.spine.promise,
    metadata: this.loading.metadata.promise,
    cover: this.loading.cover.promise,
    navigation: this.loading.navigation.promise,
    pageList: this.loading.pageList.promise
  };

  this.loaders = [];
  for(var promise in this.loaded){
    this.loaders.push(this.loaded[promise]);
  }

  this.ready = RSVP.all(this.loaders);

  // this.pageList = [];


  // this.ready.all.then(this._ready.bind(this));

  if(_url) {
    this.open(_url);
  }
};

EPUBJS.Book.prototype.open = function(_url){
  var uri;
  var parse = new EPUBJS.Parser();
  var epubPackage;
  var book = this;
  var containerPath = "META-INF/container.xml";

  // Reuse parsed url or create a new uri object
  if(typeof(_url) === "object") {
    uri = _url;
  } else {
    uri = EPUBJS.core.uri(_url);
  }

  // Find path to the Container
  if(uri.extension === "opf") {
    // Direct link to package, no container
    this.packageUrl = uri.href;
    this.containerUrl = '';
    
    if(uri.origin) {
      this.url = uri.origin + "/" + uri.directory;
    } else {
      this.url = uri.directory;
    }

    epubPackage = this.request(this.packageUrl);

  } else if(uri.extension === "epub" || uri.extension === "zip" ) {
      // Book is archived
      this.archived = true;
      this.url = '';
  }

  // Find the path to the Package from the container 
  else if (!uri.extension) {
    
    this.containerUrl = _url + containerPath;

    epubPackage = this.request(this.containerUrl).
      then(function(containerXml){
        return parse.container(containerXml); // Container has path to content
      }).
      then(function(paths){
        var packageUri = EPUBJS.core.uri(paths.packagePath);
        book.packageUrl = _url + paths.packagePath;
        book.url = _url + packageUri.directory; // Set Url relative to the content
        book.encoding = paths.encoding;

        return book.request(book.packageUrl); 
      }).catch(function(error) {
        // handle errors in either of the two requests
        console.error("Could not load book at: " + (this.packageUrl || this.containerPath));
        book.trigger("book:loadFailed", (this.packageUrl || this.containerPath));
        book.opening.reject(error);
      });
  }


  epubPackage.then(function(packageXml) {
    // Get package information from epub opf
    book.unpack(packageXml);

    // Resolve promises
    book.loading.manifest.resolve(book.package.manifest);
    book.loading.metadata.resolve(book.package.metadata);
    book.loading.spine.resolve(book.spine);
    book.loading.cover.resolve(book.cover);

    // Resolve book opened promise
    book.opening.resolve(book);

    // Clear queue of any waiting book request

  }).catch(function(error) {
    // handle errors in parsing the book
    console.error(error.message, error.stack);
    book.opening.reject(error);
  });

  return this.opened;
};

EPUBJS.Book.prototype.unpack = function(packageXml){
  var book = this,
      parse = new EPUBJS.Parser();

  book.package = parse.packageContents(packageXml); // Extract info from contents
  book.package.baseUrl = book.url; // Provides a url base for resolving paths

  book.spine = new EPUBJS.Spine(book.package, this.request);

  book.navigation = new EPUBJS.Navigation(book.package, this.request);
  book.navigation.load().then(function(toc){
    book.toc = toc;
    book.loading.navigation.resolve(book.navigation);
  });
  
  // //-- Set Global Layout setting based on metadata
  // MOVE TO RENDER
  // book.globalLayoutProperties = book.parseLayoutProperties(book.package.metadata);

  book.cover = book.url + book.package.coverPath;
};

// Alias for book.spine.get
EPUBJS.Book.prototype.section = function(target) {
  return this.spine.get(target);
};

EPUBJS.Book.prototype.request = function(_url) {
  // Switch request methods
  if(this.archived) {
    // TODO: handle archived 
  } else {
    return EPUBJS.core.request(_url, 'xml', this.credentials);
  }

};

EPUBJS.Book.prototype.setCredentials = function(_credentials) {
  this.credentials = _credentials;
};

//-- Enable binding events to book
RSVP.EventTarget.mixin(EPUBJS.Book.prototype);

//-- Handle RSVP Errors
RSVP.on('error', function(event) {
  //console.error(event, event.detail);
});

RSVP.configure('instrument', true); //-- true | will logging out all RSVP rejections
// RSVP.on('created', listener);
// RSVP.on('chained', listener);
// RSVP.on('fulfilled', listener);
RSVP.on('rejected', function(event){
  console.error(event.detail.message, event.detail.stack);
});