/*
 * IPAddressChangeNotifier.h 
 * Copyright (c) 2011 Antillia.com TOSHIYUKI ARAI. ALL RIGHTS RESERVED. 
 */


#pragma once

// SOL9
// 2008/10/10
//

#include <sol\WSAInitializer.h>
#include <sol\Thread.h>

#include <sol\net\NetworkInterfaceInfo.h>
#include <sol\StringBuffer.h>

#include <process.h>


#define WM_IPADDRESS_CHANGE    (WM_USER + 2009)

namespace SOL {

/**
 * IPAddressChangeNotifier thread class is to detect change of IPAddress and post a message 
 * WM_IADDRESS_CHANGE to a thread or window specified by Constructor.
 * The WPARAM parameter associated with the message will be TRUE or FALSE
 * which means the status of connected to the Internet or disconnected from Internet respectively.
 *
 * In this class Windows API NotifyAddrChange is used to detect an IPAddress change 
 * with non-blocking mode.
 */

class IPAddressChangeNotifier :public Thread {

private:
    NetworkInterfaceInfo info;

private:
    HANDLE termEvent;

private:
    bool looping;

private:
    DWORD threadIdNotified;

private:
    HWND  hwndNotified;

private:
    UINT  notifyMessage;

private:
    BOOL  connected;


public:
    /**
     * Constructor
     * @param threadId    Thread ID to receive a windows message to notify IP AddressChanged
     *                    (connected or disconnected to/from Internet). 
     */
    IPAddressChangeNotifier(DWORD threadId, UINT message=WM_IPADDRESS_CHANGE)
    :Thread(),
     looping(false),

     threadIdNotified(threadId),
     hwndNotified(NULL),
     notifyMessage(message),
     termEvent(NULL),
     connected(FALSE)
    {
        termEvent = CreateEvent(0,FALSE,FALSE,0);    
    }


public:
    /**
     * Constructor
     * @param hwnd    Window handle to receive a windows message to notify IP AddressChanged
     *                    (connected or disconnected to/from Internet). 
     */
    IPAddressChangeNotifier(HWND hwnd, UINT message=WM_IPADDRESS_CHANGE)
    :Thread(),
     looping(false),
     threadIdNotified(0),
     hwndNotified(hwnd),
     notifyMessage(message),
     termEvent(NULL),
     connected(FALSE)
    {
        termEvent = CreateEvent(0,FALSE,FALSE,0);    
    }

public:
    ~IPAddressChangeNotifier() {
        close();
    }


private:
    bool close()
    {
        bool rc = false;
        if (termEvent) {
            CloseHandle(termEvent);
            termEvent = NULL;
        }
        return rc;
    }

public:
    // Set termEvent to stop the run method loop.
    void stop() {
        SetEvent(termEvent);
        looping  = false;
    }


private:

    /**
     * At the first time, post a notifyMessage with a parameter of current status of connected or disconnected to/from
     * Internet to threaIdNotified or hwndNotified
     *
     */
    virtual void notifyFirstTime()
    {
        BOOL status = FALSE;
        info.listup();
        
        if (info.isConnectedToInternet()) {
            status = TRUE;        
        }

        if (threadIdNotified>0) {
            PostThreadMessage(threadIdNotified, notifyMessage, status, 0);
        }
        if (hwndNotified !=NULL) {
            PostMessage(hwndNotified, notifyMessage, status, 0);
        }
        this->connected = status;
    }

private:

    /**
     * IPAddress has been changed, so post a notifyMessage to threaIdNotified or hwndNotified
     *
     */
    virtual void notify()
    {
        BOOL status = FALSE;
        info.listup();
        
        if (info.isConnectedToInternet()) {
            status = TRUE;        
        }

        if (threadIdNotified>0 && (status != this->connected)) {
            PostThreadMessage(threadIdNotified, notifyMessage, status, 0);
        }
        if (hwndNotified !=NULL && (status != this->connected)) {
            PostMessage(hwndNotified, notifyMessage, status, 0);
        }
        this->connected = status;
    }


public:
    /**
     * Thread procedure to get notification of IPAddress changes of NeworkInterface. 
     */
    void run()
    {
        notifyFirstTime();

        OVERLAPPED ovl;
        memset(&ovl, 0, sizeof(ovl));
        ovl.hEvent   = CreateEvent(NULL, FALSE, FALSE, NULL);

        HANDLE waitEvents[2];
        waitEvents[0] = this->termEvent;
        waitEvents[1] = ovl.hEvent;

        HANDLE hFile = NULL;

        this->looping = true;

        while (looping) {
            //printf("Waiting NotifyAddrChange.No blocking here\n");

            DWORD rc = NotifyAddrChange(&hFile, &ovl);
            if (rc != NO_ERROR) {
                if (WSAGetLastError() != WSA_IO_PENDING) {
                    printf("NotifyAddrChange error...%d\n", WSAGetLastError());
                    break;
                }
            }
        
            //printf("Call Wait \n");
            
            int r = WaitForMultipleObjects(2, waitEvents, FALSE, INFINITE); 
            if (r == WAIT_OBJECT_0 ) {
                //If termEvent set to terminate this thread, 
                //then, we break this while loppStopped 
                printf("\nTerminateEvent has been set, so break this thread loop\n");
                break;
            }
            /**
            if (r == WAIT_OBJECT_0 +1) {
                notify();
            }
            */
            
            DWORD dwBytes = 0;
            //printf("Call GetOverlapped \n");
            BOOL b = GetOverlappedResult(hFile, &ovl, &dwBytes, TRUE); 
            if (b == TRUE) {
                notify();
            }
        }
        CloseHandle(ovl.hEvent);
    }

};

}