#ifndef NETWORKADDRESS_H
#define NETWORKADDRESS_H

#ifndef K_SOCKETS_NETWORKADDRESS_H
#define K_SOCKETS_NETWORKADDRESS_H

#include "../exception.h"

#include <cstring>

#include <sys/socket.h>
#include <netinet/in.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <netdb.h>


class NetworkAddress {

public:

    /**
     * @brief create NetworkAddress from the given socket address. This will
     * mainly be used for incoming data frames. The ctor re-calculuates the
     * host-ip and port-number from the given address
     * @param address the socket address to parse
     */
    NetworkAddress(const struct sockaddr_in& address) : port(0), sockAddr(address) {
        port = ntohs(sockAddr.sin_port);
        ipFromAddressStruct();
    }

    /**
     * @brief create a new NetworkAddress identified by hostname and port-number
     * @param host the host to identify (e.g. "127.0.0.1" or "google.de")
     * @param port the 16-bit port-number to use
     */
    NetworkAddress(const std::string& host, const uint16_t port) : port(port) {

        // convert hostname to ip
        struct hostent* he = gethostbyname( host.c_str() );
        if (!he) {throw Exception("error while retrieving IP for hostname: '" + host + "'");}

        // sanity checks
        // https://www.cs.rutgers.edu/~pxk/417/notes/sockets/udp.html

        // build address struct
        memset( &sockAddr, 0, sizeof(sockAddr) );
        sockAddr.sin_family = AF_INET;
        //sockAddr.sin_addr = *((struct in_addr*)he->h_addr);
        sockAddr.sin_port = htons(port);
        memcpy((void*)&sockAddr.sin_addr, he->h_addr_list[0], he->h_length);

        ipFromAddressStruct();

    }


    /**
     * @brief create a new NetworkAddress identified by the given port-number and ANY host-name
     * @param port the 16-bit port-number to use
     */
    NetworkAddress(const uint16_t port) : port(port) {

        // build address struct
        memset( &sockAddr, 0, sizeof(sockAddr) );
        sockAddr.sin_family = AF_INET;
        sockAddr.sin_addr.s_addr = htonl(INADDR_ANY);
        sockAddr.sin_port = htons(port);

        ipFromAddressStruct();

    }

    /**
     * @brief create a new NetworkAddress matching ANY host and ANY port
     * e.g. used for receiving all UDP-datagrams sent to any local port / interface
     */
    NetworkAddress() : port(0) {

        // build address struct
        memset( &sockAddr, 0, sizeof(sockAddr) );
        sockAddr.sin_family = AF_INET;
        sockAddr.sin_addr.s_addr = htonl(INADDR_ANY);
        sockAddr.sin_port = htons(0);

        ipFromAddressStruct();

    }


    /** copy ctor */
    NetworkAddress(const NetworkAddress& other) :
        port(other.port), sockAddr(other.sockAddr) {

        ipFromAddressStruct();

    }

    /** get a NetworkAddress to broadcast to the given port */
    static NetworkAddress getForBroadcast(const uint16_t port) {
        NetworkAddress adr;
        memset(&adr.sockAddr, 0, sizeof(adr.sockAddr));
        adr.sockAddr.sin_family = AF_INET;
        adr.sockAddr.sin_addr.s_addr = htonl(INADDR_BROADCAST);
        adr.sockAddr.sin_port = htons(port);
        adr.port = port;
        return adr;
    }

//		/** assignment operator */
//		void operator = (const NetworkAddress& other) {
//			this->hostName = other.hostName;
//			this->hostIP = other.hostIP;
//			this->port = other.port;
//			this->sockAddr = other.sockAddr;
//		}


    /** dtor */
    ~NetworkAddress() {
        ;
    }



    /** get the network address as sockaddr_in struct */
    const struct sockaddr_in& getAsSocketAddress() const {
        return sockAddr;
    }

//		/** get the remote's port */
//		uint16_t getPort() const {
//			return port;
//		}

//		/** get the host's IP as string */
//		const std::string& getHostIP() const {
//			return hostIP;
//		}

//		/** get the host's name as string */
//		const std::string& getHostName() {
//			if (hostName.empty()) { hostNameFromAddressStruct(); }
//			return hostName;
//		}



        /** is the internal port valid for an outbound packet? */
        bool isValidTargetPort() const {
            return port != 0;
        }

        /** is the internal ip valid for an outbound packet? */
        bool isValidTargetHost() const {
            return sockAddr.sin_addr.s_addr != htonl(INADDR_ANY);
        }



//		/** check whether both NetworkAddresses are equal */
//		bool operator == (const NetworkAddress& other) const {
//			return memcmp( &this->sockAddr, &other.sockAddr, sizeof(sockAddr)) == 0;
//		}



private:

    /** fill the hostIP string from the address struct */
    void ipFromAddressStruct() {

        uint32_t ip = sockAddr.sin_addr.s_addr;
        hostIP =	std::to_string( (ip>> 0) & 0xFF ) + "." +
                    std::to_string( (ip>> 8) & 0xFF ) + "." +
                    std::to_string( (ip>>16) & 0xFF ) + "." +
                    std::to_string( (ip>>24) & 0xFF );

    }

//		/** fill the hostName string via reverse-lookup of the address struct */
//		void hostNameFromAddressStruct() {

//			char hostNameBuf[128];
//			const int flags = 0;

//			// reverse lookup
//			getnameinfo( (struct sockaddr*) &sockAddr, sizeof(sockAddr), hostNameBuf, 128, nullptr, 0, flags );
//			this->hostName = std::string(hostNameBuf);

//		}



private:

    /** the host's ip as string */
    std::string hostIP;

    /** the host's name as string */
    std::string hostName;

    /** the port-number from the ctor */
    uint16_t port;

    /** the resulting socket-address-struct */
    struct sockaddr_in sockAddr;

};


#endif // K_SOCKETS_NETWORKADDRESS_H


#endif // NETWORKADDRESS_H