/* 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 EXPORTED_SYMBOLS = ["Stanza", "XMPPParser"];

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

const NS = {
  xml                       : "http://www.w3.org/XML/1998/namespace",
  xhtml                     : "http://www.w3.org/1999/xhtml",
  xhtml_im                  : "http://jabber.org/protocol/xhtml-im",

  //auth
  client                    : "jabber:client",
  streams                   : "http://etherx.jabber.org/streams",
  stream                    : "urn:ietf:params:xml:ns:xmpp-streams",
  sasl                      : "urn:ietf:params:xml:ns:xmpp-sasl",
  tls                       : "urn:ietf:params:xml:ns:xmpp-tls",
  bind                      : "urn:ietf:params:xml:ns:xmpp-bind",
  session                   : "urn:ietf:params:xml:ns:xmpp-session",
  auth                      : "jabber:iq:auth",
  auth_feature              : "http://jabber.org/features/iq-auth",
  http_bind                 : "http://jabber.org/protocol/httpbind",
  http_auth                 : "http://jabber.org/protocol/http-auth",
  xbosh                     : "urn:xmpp:xbosh",

  "private"                 : "jabber:iq:private",
  xdata                     : "jabber:x:data",

  //roster
  roster                    : "jabber:iq:roster",
  roster_versioning         : "urn:xmpp:features:rosterver",
  roster_delimiter          : "roster:delimiter",

  //privacy lists
  privacy                   : "jabber:iq:privacy",

  //discovering
  disco_info                : "http://jabber.org/protocol/disco#info",
  disco_items               : "http://jabber.org/protocol/disco#items",
  caps                      : "http://jabber.org/protocol/caps",

  //addressing
  address                   : "http://jabber.org/protocol/address",

  muc_user                  : "http://jabber.org/protocol/muc#user",
  muc                       : "http://jabber.org/protocol/muc",
  register                  : "jabber:iq:register",
  delay                     : "urn:xmpp:delay",
  delay_legacy              : "jabber:x:delay",
  bookmarks                 : "storage:bookmarks",
  chatstates                : "http://jabber.org/protocol/chatstates",
  event                     : "jabber:x:event",
  stanzas                   : "urn:ietf:params:xml:ns:xmpp-stanzas",
  vcard                     : "vcard-temp",
  vcard_update              : "vcard-temp:x:update",
  ping                      : "urn:xmpp:ping",

  geoloc                    : "http://jabber.org/protocol/geoloc",
  geoloc_notify             : "http://jabber.org/protocol/geoloc+notify",
  mood                      : "http://jabber.org/protocol/mood",
  tune                      : "http://jabber.org/protocol/tune",
  nick                      : "http://jabber.org/protocol/nick",
  nick_notify               : "http://jabber.org/protocol/nick+notify",
  activity                  : "http://jabber.org/protocol/activity",
  last                      : "jabber:iq:last",
  avatar_data               : "urn:xmpp:avatar:data",
  avatar_data_notify        : "urn:xmpp:avatar:data+notify",
  avatar_metadata           : "urn:xmpp:avatar:metadata",
  avatar_metadata_notify    : "urn:xmpp:avatar:metadata+notify",
  pubsub                    : "http://jabber.org/protocol/pubsub",
  pubsub_event              : "http://jabber.org/protocol/pubsub#event"
};

var TOP_LEVEL_ELEMENTS = {
  "message"             : "jabber:client",
  "presence"            : "jabber:client",
  "iq"                  : "jabber:client",
  "stream:features"     : "http://etherx.jabber.org/streams",
  "proceed"             : "urn:ietf:params:xml:ns:xmpp-tls",
  "failure"             : ["urn:ietf:params:xml:ns:xmpp-tls",
                           "urn:ietf:params:xml:ns:xmpp-sasl"],
  "success"             : "urn:ietf:params:xml:ns:xmpp-sasl",
  "challenge"           : "urn:ietf:params:xml:ns:xmpp-sasl",
  "error"               : "urn:ietf:params:xml:ns:xmpp-streams"
};

/* Stanza Builder */
const Stanza = {
  NS: NS,

  /* Create a presence stanza */
  presence: function(aAttr, aData) Stanza.node("presence", null, aAttr, aData),

  /* Create a message stanza */
  message: function(aTo, aMsg, aState, aAttr, aData) {
    if (!aAttr)
      aAttr = {};

    aAttr.to = aTo;
    if (!("type" in aAttr))
      aAttr.type = "chat";

    if (!aData)
      aData = [];

    if (aMsg)
      aData.push(Stanza.node("body", null, null, aMsg));

    if (aState)
      aData.push(Stanza.node(aState, Stanza.NS.chatstates));

    return Stanza.node("message", null, aAttr, aData);
  },

  /* Create a iq stanza */
  iq: function(aType, aId, aTo, aData) {
    let attrs = {type: aType};
    if (aId)
      attrs.id = aId;
    if (aTo)
      attrs.to = aTo;
    return this.node("iq", null, attrs, aData);
  },

  /* Create a XML node */
  node: function(aName, aNs, aAttr, aData) {
    let n = new XMLNode(null, aNs, aName, aName, null);

    if (aAttr) {
      for (let at in aAttr)
        n.attributes[at] = aAttr[at];
    }

    if (aData) {
      if (!Array.isArray(aData))
        aData = [aData];
      for each (let child in aData)
        n[typeof(child) == "string" ? "addText" : "addChild"](child);
    }

    return n;
  }
};

/* Text node
 * Contains a text */
function TextNode(aText) {
  this.text = aText;
}
TextNode.prototype = {
  get type() "text",

  append: function(aText) {
    this.text += aText;
  },

  /* For debug purposes, returns an indented (unencoded) string */
  convertToString: function(aIndent) aIndent + this.text + "\n",

  /* Returns the encoded XML */
  getXML: function()
    Cc["@mozilla.org/txttohtmlconv;1"]
      .getService(Ci.mozITXTToHTMLConv)
      .scanTXT(this.text, Ci.mozITXTToHTMLConv.kEntities),

  /* To read the unencoded data. */
  get innerText() this.text
};

/* XML node */
function XMLNode(aParentNode, aUri, aLocalName, aQName, aAttr) {
  this._parentNode = aParentNode; // Used only for parsing
  this.uri = aUri;
  this.localName = aLocalName;
  this.qName = aQName;
  this.attributes = {};
  this.children = [];

  if (aAttr) {
    for (let i = 0; i < aAttr.length; ++i)
      this.attributes[aAttr.getQName(i)] = aAttr.getValue(i);
  }
}
XMLNode.prototype = {
  get type() "node",

  /* Add a new child node */
  addChild: function(aNode) {
    this.children.push(aNode);
  },

  /* Add text node */
  addText: function(aText) {
    let lastIndex = this.children.length - 1;
    if (lastIndex >= 0 && this.children[lastIndex] instanceof TextNode)
      this.children[lastIndex].append(aText);
    else
      this.children.push(new TextNode(aText));
  },

  /* Get child elements by namespace */
  getChildrenByNS: function(aNS)
    this.children.filter(function(c) c.uri == aNS),

  /* Get the first element inside the node that matches a query. */
  getElement: function(aQuery) {
    if (aQuery.length == 0)
      return this;

    let nq = aQuery.slice(1);
    for each (let child in this.children) {
      if (child.qName != aQuery[0])
        continue;
      let n = child.getElement(nq);
      if (n)
        return n;
    }

    return null;
  },

  /* Get all elements matching the query */
  getElements: function(aQuery) {
    if (aQuery.length == 0)
      return [this];

    let c = this.getChildren(aQuery[0]);
    let nq = aQuery.slice(1);
    let res = [];
    for each (let child in c) {
      let n = child.getElements(nq);
      res = res.concat(n);
    }

    return res;
  },

  /* Get immediate children by the node name */
  getChildren: function(aName)
    this.children.filter(function(c) c.qName == aName),

  /* Test if the node is a stanza */
  isXmppStanza: function() {
    if (!TOP_LEVEL_ELEMENTS.hasOwnProperty(this.qName))
      return false;
    let ns = TOP_LEVEL_ELEMENTS[this.qName];
    return ns == this.uri || (Array.isArray(ns) && ns.indexOf(this.uri) != -1);
  },

  /* Returns indented XML */
  convertToString: function(aIndent) {
    if (!aIndent)
      aIndent = "";

    let s =
      aIndent + "<" + this.qName + this._getXmlns() + this._getAttributeText();
    let content = "";
    for each (let child in this.children)
      content += child.convertToString(aIndent + " ");
    return s + (content ? ">\n" + content + aIndent + "</" + this.qName : "/") + ">\n";
  },

  /* Returns the XML */
  getXML: function() {
    let s = "<" + this.qName + this._getXmlns() + this._getAttributeText();
    let innerXML = this.innerXML;
    return s + (innerXML ? ">" + innerXML + "</" + this.qName : "/") + ">";
  },

  get innerXML() this.children.map(function(c) c.getXML()).join(""),
  get innerText() this.children.map(function(c) c.innerText).join(""),

  /* Private methods */
  _getXmlns: function() this.uri ? " xmlns=\"" + this.uri + "\"" : "",
  _getAttributeText: function() {
    let s = "";
    for (let name in this.attributes)
      s += " " +name + "=\"" + this.attributes[name] + "\"";
    return s;
  }
};

function XMPPParser(aListener) {
  this._parser = Cc["@mozilla.org/saxparser/xmlreader;1"]
                   .createInstance(Ci.nsISAXXMLReader);
  this._parser.contentHandler = this;
  this._parser.errorHandler = this;
  this._parser.parseAsync(null);
  this._listener = aListener;
  this._parser.onStartRequest(this._dummyRequest, null);
}
XMPPParser.prototype = {
  _destroyPending: false,
  destroy: function() {
    // Avoid reference cycles
    this._parser.contentHandler = null;
    delete this._listener;
    // Calling onStopRequest while we are in an onDataAvailable
    // callback crashes, don't do it.
    if (this._inOnDataAvailable) {
      this._destroyPending = true;
      return;
    }
    this._parser.onStopRequest(this._dummyRequest, null, Cr.NS_OK);
    // Stopping the request causes parse errors (because we parsed
    // only partial XML documents?), so the error handler is still
    // needed to avoid the errors being reported to the error console.
    this._parser.errorHandler = null;
    delete this._parser;
  },
  _dummyRequest: {
    cancel: function() { },
    isPending: function() { },
    resume: function() { },
    suspend: function() { }
  },

  _logReceivedData: function(aData) {
    this._listener.LOG("received:\n" + aData);
  },
  _inOnDataAvailable: false,
  onDataAvailable: function(aInputStream, aOffset, aCount) {
    this._inOnDataAvailable = true;
    this._parser.onDataAvailable(this._dummyRequest, null,
                                 aInputStream, aOffset, aCount);
    delete this._inOnDataAvailable;
    if (this._destroyPending)
      this.destroy();
  },

  /* nsISAXContentHandler implementation */
  startDocument: function() { },
  endDocument: function() { },

  startElement: function(aUri, aLocalName, aQName, aAttributes) {
    if (aQName == "stream:stream") {
      let node = new XMLNode(null, aUri, aLocalName, aQName, aAttributes);
      // The node we created doesn't have children, but
      // <stream:stream> isn't closed, so avoid displaying /> at the end.
      this._logReceivedData(node.convertToString().slice(0, -3) + ">\n");

      if ("_node" in this) {
        this._listener.onXMLError("unexpected-stream-start",
                                  "stream:stream inside an already started stream");
        return;
      }

      this._listener._streamId = node.attributes["id"];
      if (!("version" in node.attributes))
        this._listener.startLegacyAuth();

      this._node = null;
      return;
    }

    let node = new XMLNode(this._node, aUri, aLocalName, aQName, aAttributes);
    if (this._node)
      this._node.addChild(node);

    this._node = node;
  },

  characters: function(aCharacters) {
    if (!this._node) {
      // Ignore whitespace received on the stream to keep the connection alive.
      if (aCharacters.trim()) {
        this._listener.onXMLError("parsing-characters",
                                  "No parent for characters: " + aCharacters);
      }
      return;
    }

    this._node.addText(aCharacters);
  },

  endElement: function(aUri, aLocalName, aQName) {
    if (aQName == "stream:stream") {
      this._logReceivedData("</stream:stream>");
      delete this._node;
      return;
    }

    if (!this._node) {
      this._listener.onXMLError("parsing-node",
                                "No parent for node : " + aLocalName);
      return;
    }

    if (this._node.isXmppStanza()) {
      this._logReceivedData(this._node.convertToString());
      try {
        this._listener.onXmppStanza(this._node);
      } catch (e) {
        Cu.reportError(e);
        dump(e + "\n");
      }
    }

    this._node = this._node._parentNode;
  },

  processingInstruction: function(aTarget, aData) { },
  ignorableWhitespace: function(aWhitespace) { },
  startPrefixMapping: function(aPrefix, aUri) { },
  endPrefixMapping: function(aPrefix) { },

  /* nsISAXErrorHandler implementation */
  error: function(aLocator, aError) {
    if (this._listener)
      this._listener.onXMLError("parse-error", aError);
  },
  fatalError: function(aLocator, aError) {
    if (this._listener)
      this._listener.onXMLError("parse-fatal-error", aError);
  },
  ignorableWarning: function(aLocator, aError) {
    if (this._listener)
      this._listener.onXMLError("parse-warning", aError);
  },

  QueryInterface: function(aInterfaceId) {
    if (!aInterfaceId.equals(Ci.nsISupports) &&
        !aInterfaceId.equals(Ci.nsISAXContentHandler) &&
        !aInterfaceId.equals(Ci.nsISAXErrorHandler))
      throw Cr.NS_ERROR_NO_INTERFACE;
    return this;
  }
};
