gistfile1.swift

//
//  HarmonyDiscovery.swift
//  XMPPFun
//
//  Created by Joshua Weinberg on 4/25/15.
//  Copyright (c) 2015 Joshua Weinberg. All rights reserved.
//

import Foundation

@objc public class HarmonyDiscovery : NSObject {
    private let _socketQueue: dispatch_queue_t
    private let _timer: dispatch_source_t
    private var _socketSource: dispatch_source_t?
    
    override init() {
        _socketQueue = dispatch_queue_create("com.jweinberg.socket", DISPATCH_QUEUE_SERIAL)
        _timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, dispatch_get_main_queue());
    }
    
    private func readDeviceInformation(data: NSData) -> [String:String] {
        if let string = NSString(bytes: data.bytes, length: data.length, encoding: NSUTF8StringEncoding) as? String {
            var deviceInformation = [String:String]()
            for source in string.componentsSeparatedByString(";") {
                let pair = source.componentsSeparatedByString(":")
                if pair.count > 1 {
                    deviceInformation[pair[0]] = pair[1]
                }
            }
            return deviceInformation
        }
        return [:]
    }
    
    public func startDiscovery(callback: ([String:String]?) -> ()) {
        var server = sockaddr_in()
        server.sin_family = sa_family_t(AF_INET)
        server.sin_addr = in_addr(s_addr: 0)
        server.sin_port = CFSwapInt16HostToBig(58391)
        
        let tcpsock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)
        
        _socketSource = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, UInt(tcpsock), 0, _socketQueue)
        
        setsockopt(tcpsock, SOL_SOCKET, SO_REUSEADDR, &server, socklen_t(sizeof(sockaddr_in)))
        
        var saddr = unsafeBitCast(server, sockaddr.self)
        bind(tcpsock, &saddr, socklen_t(sizeof(sockaddr)))
        
        dispatch_source_set_event_handler(_socketSource!) {
            let data = NSMutableData()
            var buff = [UInt8](count: 1024, repeatedValue: 0)
            let accepted = accept(tcpsock, nil, nil)
            
            var count = 0;
            do {
                count = read(accepted, &buff, 1024)
                data.appendBytes(buff, length: count)
            } while count > 0
    
            callback(self.readDeviceInformation(data))
        }
        
        dispatch_resume(_socketSource!)
        listen(tcpsock, 1024)
        
        var bPort = sockaddr_in()
        bPort.sin_family = sa_family_t(AF_INET)
        
        var bAddr = in_addr()
        inet_pton(AF_INET, "192.168.2.255", &bAddr)
        bPort.sin_addr = bAddr
        bPort.sin_port = CFSwapInt16HostToBig(5224)

        let sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)
        
        // set socket options enable broadcast
        var broadcastEnable = 1
        setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &broadcastEnable, socklen_t(sizeof(Int)))

        dispatch_source_set_timer(_timer, DISPATCH_TIME_NOW, 5 * NSEC_PER_SEC, NSEC_PER_SEC / 10)
        dispatch_source_set_event_handler(_timer) {
            let request = "_logitech-reverse-bonjour._tcp.local.\n58391";
            let buf = [UInt8](request.utf8)
            var bAddr = unsafeBitCast(bPort, sockaddr.self)
            sendto(sock, buf, Int(count(buf)), Int32(0), &bAddr, socklen_t(sizeof(sockaddr_in)))
        }
        
        dispatch_resume(_timer)
    }
}