/*
   Copyright (c)  2014 IOnU Security Inc. All rights reserved
   Created February 2014 by Kendrick Webster
 
   UdpIpc.h - header for UDP-based inter-process communication
*/
#pragma once
#include <string.h>
#include "Network.h"

namespace ionu { namespace udp_ipc {
    
    constexpr uint16_t PORT_DYNAMIC = 0;  // for InitSocket
    constexpr uint16_t PORT_LOOPBACK = 0; // for SendTo

    // Initialize the UDP socket to listen on <port> (host byte order, 0 for dynamic)
    // with socket timeout set to <timeout_milliseconds>.  Logs messages indicating result
    // (port number that was bound) or error details if an error occurs.  Use <Log::ignore>
    // to suppress log output, if desired.
    success_t InitSocket(uint16_t port, uint32_t timeout_milliseconds,
        Log::severity_t trace_loglevel = Log::informational,  // severity for logging bound address
        Log::severity_t error_loglevel = Log::error); // severity for logging errors


    // Sends message <s> to destination <a> via UDP best-effort delivery.
    // Returns <SUCCESS> if a message was sent, logs reason for failure otherwise.
    // If a catestrophic failure occurs, logs a message and calls exit(EXIT_FAILURE).
    success_t SendTo(ionu::network::CAddress a, const std::string& s);

    inline success_t SendTo(ionu::network::CAddress a, const std::string& s1, const std::string& s2)
    {
        std::string s(s1);
        s += s2;
        return SendTo(a, s);
    }

    inline success_t SendToSelf(const std::string& s)
    {
        ionu::network::CAddress a;
        return SendTo(a, s);
    }
        
    inline success_t SendToSelf(const std::string& s1, const std::string& s2)
    {
        std::string s(s1);
        s += s2;
        return SendToSelf(s);
    }

    // Checks for a received message, blocks for at most InitSocket( <timeout_milliseconds> ).
    // If a message was received, returns <true> with source address in <a> and message in <s>.
    // If a catestrophic failure occurs, logs a message and calls exit(EXIT_FAILURE).
    bool ReceiveFrom(ionu::network::CAddress& a, std::string& s);

        
    // String splitter for IPC message subfields
    constexpr char MESSAGE_FIELD_DELIMITER = ':';
    inline void SplitString(const std::string& s, std::string& s1, std::string& s2)
    {
        const char* p = s.c_str();
        const char* q = strchr(p, MESSAGE_FIELD_DELIMITER);
        if (q)
        {
            s1.assign(p, q - p);
            s2 = q + 1;
        }
        else
        {
            s1 = s;
            s2 = "";
        }
    }

}}