var client = require('../surface_client.js');

var builder = ProtoBuf.loadProtoFile(__dirname + '/../examples/math.proto');
var math = builder.build('math');

/**
 * Get a function that deserializes a specific type of protobuf.
 * @param {function()} cls The constructor of the message type to deserialize
 * @return {function(Buffer):cls} The deserialization function
 */
function deserializeCls(cls) {
  /**
   * Deserialize a buffer to a message object
   * @param {Buffer} arg_buf The buffer to deserialize
   * @return {cls} The resulting object
   */
  return function deserialize(arg_buf) {
    return cls.decode(arg_buf);
  };
}

/**
 * Serialize an object to a buffer
 * @param {*} arg The object to serialize
 * @return {Buffer} The serialized object
 */
function serialize(arg) {
  return new Buffer(arg.encode.toBuffer());
}

/**
 * Sends a Div request on the channel.
 * @param {client.Channel} channel The channel on which to make the request
 * @param {*} argument The argument to the call. Should be serializable with
 *     serialize
 * @param {function(?Error, value=)} The callback to for when the response is
 *     received
 * @param {array=} Array of metadata key/value pairs to add to the call
 * @param {(number|Date)=} deadline The deadline for processing this request.
 *     Defaults to infinite future
 * @return {EventEmitter} An event emitter for stream related events
 */
var div = client.makeUnaryRequestFunction('/Math/Div',
                                          serialize,
                                          deserialize(math.DivReply));

/**
 * Sends a Fib request on the channel.
 * @param {client.Channel} channel The channel on which to make the request
 * @param {*} argument The argument to the call. Should be serializable with
 *     serialize
 * @param {array=} Array of metadata key/value pairs to add to the call
 * @param {(number|Date)=} deadline The deadline for processing this request.
 *     Defaults to infinite future
 * @return {EventEmitter} An event emitter for stream related events
 */
var fib = client.makeServerStreamRequestFunction('/Math/Fib',
                                                 serialize,
                                                 deserialize(math.Num));

/**
 * Sends a Sum request on the channel.
 * @param {client.Channel} channel The channel on which to make the request
 * @param {function(?Error, value=)} The callback to for when the response is
 *     received
 * @param {array=} Array of metadata key/value pairs to add to the call
 * @param {(number|Date)=} deadline The deadline for processing this request.
 *     Defaults to infinite future
 * @return {EventEmitter} An event emitter for stream related events
 */
var sum = client.makeClientStreamRequestFunction('/Math/Sum',
                                                 serialize,
                                                 deserialize(math.Num));

/**
 * Sends a DivMany request on the channel.
 * @param {client.Channel} channel The channel on which to make the request
 * @param {array=} Array of metadata key/value pairs to add to the call
 * @param {(number|Date)=} deadline The deadline for processing this request.
 *     Defaults to infinite future
 * @return {EventEmitter} An event emitter for stream related events
 */
var divMany = client.makeBidiStreamRequestFunction('/Math/DivMany',
                                                   serialize,
                                                   deserialize(math.DivReply));

var channel = new client.Channel('localhost:7070');