import { util } from "./util";
import { EventEmitter } from "eventemitter3";
import { Negotiator } from "./negotiator";

/**
 * Wraps the streaming interface between two Peers.
 */
export function MediaConnection(peer, provider, options) {
  if (!(this instanceof MediaConnection))
    return new MediaConnection(peer, provider, options);
  EventEmitter.call(this);

  this.options = util.extend({}, options);

  this.open = false;
  this.type = "media";
  this.peer = peer;
  this.provider = provider;
  this.metadata = this.options.metadata;
  this.localStream = this.options._stream;

  this.id =
    this.options.connectionId || MediaConnection._idPrefix + util.randomToken();
  if (this.localStream) {
    Negotiator.startConnection(this, {
      _stream: this.localStream,
      originator: true
    });
  }
}

util.inherits(MediaConnection, EventEmitter);

MediaConnection._idPrefix = "mc_";

MediaConnection.prototype.addStream = function(remoteStream) {
  util.log("Receiving stream", remoteStream);

  this.remoteStream = remoteStream;
  this.emit("stream", remoteStream); // Should we call this `open`?
};

MediaConnection.prototype.handleMessage = function(message) {
  var payload = message.payload;

  switch (message.type) {
    case "ANSWER":
      // Forward to negotiator
      Negotiator.handleSDP(message.type, this, payload.sdp);
      this.open = true;
      break;
    case "CANDIDATE":
      Negotiator.handleCandidate(this, payload.candidate);
      break;
    default:
      util.warn(
        "Unrecognized message type:",
        message.type,
        "from peer:",
        this.peer
      );
      break;
  }
};

MediaConnection.prototype.answer = function(stream) {
  if (this.localStream) {
    util.warn(
      "Local stream already exists on this MediaConnection. Are you answering a call twice?"
    );
    return;
  }

  this.options._payload._stream = stream;

  this.localStream = stream;
  Negotiator.startConnection(this, this.options._payload);
  // Retrieve lost messages stored because PeerConnection not set up.
  var messages = this.provider._getMessages(this.id);
  for (var i = 0, ii = messages.length; i < ii; i += 1) {
    this.handleMessage(messages[i]);
  }
  this.open = true;
};

/**
 * Exposed functionality for users.
 */

/** Allows user to close connection. */
MediaConnection.prototype.close = function() {
  if (!this.open) {
    return;
  }
  this.open = false;
  Negotiator.cleanup(this);
  this.emit("close");
};