/* -*- compile-command: "make -j2 TARGET_OS=win32 DEBUG=TRUE" -*- */
/* 
 * Copyright 2005-2009 by Eric House (xwords@eehouse.org).  All rights
 * reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
#ifndef XWFEATURE_STANDALONE_ONLY

#include <winsock2.h>
#include <stdio.h>

#include "bufqueue.h"

#include "cesockwr.h"
#include "cemain.h"
#include "cedebug.h"
#include "debhacks.h"
#include "ceconnmg.h"


/* This object owns all network activity: sending and receiving packets.  It
   maintains two threads, one to send and the other to listen.  Incoming
   packets are passed out via a proc passed into the "constructor".  Outgoing
   packets are passed in directly.  Uses TCP, and the relay framing protocol
   wherein each packet is proceeded by its length in two bytes, network byte
   order.
*/

#define MAX_QUEUE_SIZE 6

struct CeSocketWrapper {
    HWND hWnd;
    DataRecvProc dataProc;
    StateChangeProc stateProc;
#if defined _WIN32_WCE
# if ! defined CEGCC_DOES_CONNMGR
    const CMProcs* cmProcs;
# endif
    HANDLE connMgrHandle;
#endif
    void* closure;

    union {
        HOSTENT hent;
        XP_U8 hostNameBuf[MAXGETHOSTSTRUCT];
    } hostNameUnion;
    HANDLE getHostTask;

    /* PENDING rewrite this as one sliding buffer */
    /* Outgoing queue */
    XP_U8 bufOut[512];
    BufQueue queueOut;

    /* Incoming */
    char in_buf[512];           /* char is what WSARecv wants */
    XP_U16 in_offset;

    CommsAddrRec addrRec;

    SOCKET socket;
    CeConnState connState;

#ifdef DEBUG
    XP_U16 nSent;
#endif

    MPSLOT
};

#ifdef _WIN32_WCE
# ifdef CEGCC_DOES_CONNMGR
#  define CMCALL(proc) proc
# else
#  define CMCALL(proc) (*self->cmProcs->proc)
# endif
#endif

#ifdef DEBUG
static const char*
ConnState2Str( CeConnState connState )
{
#define CASESTR(s)   case (s): return #s
    switch( connState ) {
        CASESTR( CE_IPST_START );
#ifdef _WIN32_WCE
        CASESTR( CE_IPST_OPENING_NETWORK );
        CASESTR( CE_IPST_NETWORK_OPENED );
#endif
        CASESTR( CE_IPST_RESOLVINGHOST );
        CASESTR( CE_IPST_HOSTRESOLVED );
        CASESTR( CE_IPST_CONNECTING );
        CASESTR( CE_IPST_CONNECTED );
    }
#undef CASESTR
    return "<unknown>";
}
#else
# define ConnState2Str(s)
#endif

/* Forward decls */
static void getHostAddr( CeSocketWrapper* self );
static XP_Bool connectIfNot( CeSocketWrapper* self );

static XP_Bool
sendAll( CeSocketWrapper* self, const XP_U8* buf, XP_U16 len )
{
    for ( ; ; ) {
        int nSent = send( self->socket, (char*)buf, len, 0 ); /* flags? */
        if ( nSent == SOCKET_ERROR ) {
            return XP_FALSE;
        } else if ( nSent == len ) {
            XP_LOGF( "sent %d bytes", nSent );
            return XP_TRUE;
        } else {
            XP_LOGF( "sent %d bytes", nSent );
            XP_ASSERT( nSent < len );
            len -= nSent;
            buf += nSent;
        }
    }
} /* sendAll */

static XP_Bool
sendLenAndData( CeSocketWrapper* self, const XP_U8* packet, XP_U16 len )
{
    XP_LOGF( "%s(len=%d)", __func__, len );
    XP_Bool success;
    XP_U16 lenData;
    XP_ASSERT( self->socket != -1 );

    lenData = XP_HTONS( len );
    success = sendAll( self, (XP_U8*)&lenData, sizeof(lenData) )
        && sendAll( self, packet, len );
    LOG_RETURNF( "%s", success?"success":"failed" );
    return success;
} /* sendLenAndData */

static void
send_packet_if( CeSocketWrapper* self )
{
    const XP_U8* packet;
    XP_U16 len;
    if ( self->socket == -1 ) {
        XP_LOGF( "%s: have no socket", __func__ );
    } else if ( bqGet( &self->queueOut, &packet, &len ) ) {
        if ( sendLenAndData( self, packet, len ) ) {
            /* successful send.  Remove our copy */
            bqRemoveOne( &self->queueOut );
        }
    }
}

static void
stateChanged( CeSocketWrapper* self, CeConnState newState )
{
    CeConnState curState = self->connState;
    self->connState = newState;

    XP_LOGF( "%s: %s -> %s", __func__, ConnState2Str( curState ), 
             ConnState2Str( newState ) );

    (*self->stateProc)( self->closure, curState, newState );

    switch( newState ) {
    case CE_IPST_START:
        break;
#ifdef _WIN32_WCE
    case CE_IPST_OPENING_NETWORK:
        break;
    case CE_IPST_NETWORK_OPENED:
        getHostAddr( self );
        break;
#endif
    case CE_IPST_RESOLVINGHOST:
        break;
    case CE_IPST_HOSTRESOLVED:
        connectIfNot( self );
        break;
    case CE_IPST_CONNECTING:
        break;
    case CE_IPST_CONNECTED:
        send_packet_if( self );
        break;
    }
} /* stateChanged */

static XP_Bool
connectSocket( CeSocketWrapper* self )
{
    SOCKET sock;

    if ( self->addrRec.u.ip_relay.ipAddr != 0 ) {
        sock = WSASocket( AF_INET, SOCK_STREAM, IPPROTO_IP, 
                          NULL, 0, WSA_FLAG_OVERLAPPED );
        XP_LOGF( "got socket %d", sock );

        if ( sock != INVALID_SOCKET ) {
            struct sockaddr_in name = {0};

            /* Put socket in non-blocking mode */
            if ( 0 != WSAAsyncSelect( sock, self->hWnd,
                                      XWWM_SOCKET_EVT,
                                      FD_READ | FD_WRITE | FD_CONNECT
                                      | FD_CLOSE ) ) {
                XP_WARNF( "WSAAsyncSelect failed" );
            }

            name.sin_family = AF_INET;
            name.sin_port = XP_HTONS( self->addrRec.u.ip_relay.port );
            name.sin_addr.S_un.S_addr = XP_HTONL(self->addrRec.u.ip_relay.ipAddr);

            XP_LOGF( "%s: calling WSAConnect: port=%d; host=%lx", __func__,
                     self->addrRec.u.ip_relay.port,
                     self->addrRec.u.ip_relay.ipAddr );

            if ( SOCKET_ERROR != WSAConnect( sock, (struct sockaddr *)&name, 
                                             sizeof(name), NULL, NULL, 
                                             NULL, NULL ) ) {
                self->socket = sock;
                stateChanged( self, CE_IPST_CONNECTING );
            } else if ( WSAEWOULDBLOCK == WSAGetLastError() ) {
                stateChanged( self, CE_IPST_CONNECTING );
            } else {
                XP_LOGF( "%s:%d: WSAGetLastError=>%d", __func__, __LINE__, 
                         WSAGetLastError() );
            }
        } else {
            XP_LOGF( "%s:%d: WSAGetLastError=>%d", __func__, __LINE__, 
                     WSAGetLastError() );
        }
    }

    LOG_RETURNF( "%d", self->connState == CE_IPST_CONNECTED );
    return self->connState == CE_IPST_CONNECTED;
} /* connectSocket */

static XP_Bool
connectIfNot( CeSocketWrapper* self )
{
    LOG_FUNC();
    XP_Bool success = self->connState == CE_IPST_CONNECTED;

    if ( !success && CE_IPST_HOSTRESOLVED == self->connState ) {
        success = connectSocket( self );
    }
    return success;
} /* connectIfNot */

static void
closeConnection( CeSocketWrapper* self )
{
    if ( self->connState >= CE_IPST_CONNECTED ) {
        XP_ASSERT( self->socket != -1 );
        if ( self->socket != -1 ) {
            closesocket( self->socket );
            self->socket = -1;
        }
    }

    bqRemoveAll( &self->queueOut );

    XP_ASSERT( self->socket == -1 );
    stateChanged( self, CE_IPST_START );
} /* closeConnection */

#ifdef _WIN32_WCE
static void
openNetwork( CeSocketWrapper* self )
{
    HRESULT res;

    if ( !!self->connMgrHandle ) { /* already have a connection? */
        DWORD status;
        res = CMCALL(ConnMgrConnectionStatus)( self->connMgrHandle, &status );
        if ( SUCCEEDED(res) && status == CONNMGR_STATUS_CONNECTED ) {
            stateChanged( self, CE_IPST_NETWORK_OPENED );
        } else {
            CMCALL(ConnMgrReleaseConnection)( self->connMgrHandle, 1 );
            self->connMgrHandle = NULL;
        }
    }

    if ( !self->connMgrHandle ) {
        CONNMGR_CONNECTIONINFO cmi;
        HANDLE hand;
        XP_MEMSET( &cmi, 0, sizeof(cmi) );

        res = CMCALL(ConnMgrMapURL)( L"http://google.com", 
                                               &cmi.guidDestNet, NULL );
        if ( SUCCEEDED(res) ) {
            cmi.cbSize = sizeof(cmi);
            cmi.bExclusive = FALSE;
            cmi.dwPriority = CONNMGR_PRIORITY_USERINTERACTIVE;
            cmi.dwParams = CONNMGR_PARAM_GUIDDESTNET;
            cmi.dwFlags = CONNMGR_FLAG_PROXY_HTTP;
            cmi.hWnd = self->hWnd;
            cmi.uMsg = XWWM_CONNMGR_EVT;

            res = CMCALL(ConnMgrEstablishConnection)( &cmi, &hand );
            if ( SUCCEEDED(res) ) {
                self->connMgrHandle = hand;
                stateChanged( self, CE_IPST_OPENING_NETWORK );
            }
        }
    }
} /* openNetwork */
#endif

static void
getHostAddr( CeSocketWrapper* self )
{
    if ( self->addrRec.u.ip_relay.hostName[0] ) {
        XP_LOGF( "%s: calling WSAAsyncGetHostByName(%s)", 
                 __func__, self->addrRec.u.ip_relay.hostName );
        XP_ASSERT( !self->getHostTask );
        self->getHostTask
            = WSAAsyncGetHostByName( self->hWnd,
                                     XWWM_HOSTNAME_ARRIVED,
                                     self->addrRec.u.ip_relay.hostName,
                                     (char*)&self->hostNameUnion,
                                     sizeof(self->hostNameUnion) );
        if ( NULL == self->getHostTask ) {
            XP_LOGF( "%s: WSAGetLastError=>%d", __func__, WSAGetLastError() );
        }

        stateChanged( self, CE_IPST_RESOLVINGHOST );
    }
}

CeSocketWrapper* 
ce_sockwrap_new( MPFORMAL HWND hWnd, DataRecvProc dataCB, 
                 StateChangeProc stateCB, 
#if defined _WIN32_WCE && ! defined CEGCC_DOES_CONNMGR
                 const CMProcs* cmProcs, 
#endif
                 void* closure )
{
    CeSocketWrapper* self = NULL;

    self = XP_MALLOC( mpool, sizeof(*self) );
    XP_MEMSET( self, 0, sizeof(*self) );

    self->hWnd = hWnd;
    self->dataProc = dataCB;
    self->stateProc = stateCB;
#if defined _WIN32_WCE && ! defined CEGCC_DOES_CONNMGR
    self->cmProcs = cmProcs;
#endif
    self->closure = closure;
    MPASSIGN(self->mpool, mpool );
    self->socket = -1;

    bqInit( &self->queueOut, self->bufOut, sizeof(self->bufOut) );

/* #ifdef _WIN32_WCE */
/*     openNetwork( self );    /\* kicks off connection process *\/ */
/* #else */
/*     getHostAddr( self );    /\* kicks off connection process *\/ */
/* #endif */
    return self;
} /* ce_sockwrap_new */

void
ce_sockwrap_delete( CeSocketWrapper* self )
{
    /* This isn't a good thing to do.  Better to signal them to exit
       some other way */
    closeConnection( self );

#ifdef _WIN32_WCE
    if ( !!self->connMgrHandle ) {
        CMCALL(ConnMgrReleaseConnection)( self->connMgrHandle, 1 );
        self->connMgrHandle = NULL;
    }
#endif

    XP_FREE( self->mpool, self );
} /* ce_sockwrap_delete */

void
ce_sockwrap_hostname( CeSocketWrapper* self, WPARAM wParam, LPARAM lParam )
{
    LOG_FUNC();
    XP_ASSERT( !!self );
    DWORD err = WSAGETASYNCERROR( lParam );

    XP_ASSERT( CE_IPST_RESOLVINGHOST == self->connState );

    if ( 0 == err ) {
        if ( (HANDLE)wParam != self->getHostTask ) {
            XP_LOGF( "%s: ignoring old event", __func__ );
        } else {

            XP_U32 tmp;
            XP_MEMCPY( &tmp, &self->hostNameUnion.hent.h_addr_list[0][0], 
                       sizeof(tmp) );
            self->addrRec.u.ip_relay.ipAddr = XP_NTOHL( tmp );

            XP_LOGF( "got address: %d.%d.%d.%d", 
                     (int)((tmp>>0) & 0xFF), 
                     (int)((tmp>>8) & 0xFF), 
                     (int)((tmp>>16) & 0xFF), 
                     (int)((tmp>>24) & 0xFF) );

            stateChanged( self, CE_IPST_HOSTRESOLVED );
            self->getHostTask = NULL;
        }
    } else {
        XP_LOGF( "%s: async operation failed: %ld", __func__, err );
/* WSAENETDOWN */
/* WSAENOBUFS */
/* WSAEFAULT */
/* WSAHOST_NOT_FOUND */
/* WSATRY_AGAIN */
/* WSANO_RECOVERY */
/* WSANO_DATA */
    }
} /* ce_sockwrap_hostname */

static XP_Bool
dispatch_msgs( CeSocketWrapper* self )
{
    XP_Bool draw = XP_FALSE;

    /* Repeat until we don't have a complete message in the buffer */
    for ( ; ; ) {
        XP_U16 lenInBuffer = self->in_offset;
        XP_U16 msgLen;
        XP_U16 lenUsed, lenLeft;

        XP_LOGF( "%s: have %d bytes", __func__, lenInBuffer );

        /* Do we even have the length header? */
        if ( lenInBuffer < sizeof(msgLen) ) {
            break;
        }

        XP_MEMCPY( &msgLen, self->in_buf, sizeof(msgLen) );
        msgLen = XP_NTOHS( msgLen );

        XP_LOGF( "%s: at least we have len: %d", __func__, msgLen );

        /* We know the length of the full buffer.  Do we have it? */
        if ( lenInBuffer < (msgLen + sizeof(msgLen)) ) {
            break;
        }

        /* first send */
        XP_LOGF( "%s: sending %d bytes to dataProc", __func__, msgLen );
        draw = (*self->dataProc)( (XP_U8*)&self->in_buf[sizeof(msgLen)], 
                                  msgLen, self->closure )
            || draw;

        /* then move down any additional bytes */
        lenUsed = msgLen + sizeof(msgLen);
        XP_ASSERT( lenInBuffer >= lenUsed );
        lenLeft = lenInBuffer - lenUsed;
        if ( lenLeft > 0 ) {
            XP_MEMCPY( self->in_buf, &self->in_buf[lenUsed], lenLeft );
        }

        self->in_offset = lenLeft;
    }

    return draw;
} /* dispatch_msgs */

static XP_Bool
read_from_socket( CeSocketWrapper* self )
{
    WSABUF wsabuf;
    DWORD flags = 0;
    DWORD nBytesRecvd = 0;

    wsabuf.buf = &self->in_buf[self->in_offset];
    wsabuf.len = sizeof(self->in_buf) - self->in_offset;

    int err = WSARecv( self->socket, &wsabuf, 1, &nBytesRecvd, 
                       &flags, NULL, NULL );
    XP_ASSERT( nBytesRecvd < 0xFFFF );

    if ( 0 == err ) {
        XP_LOGF( "%s: got %ld bytes", __func__, nBytesRecvd );
        self->in_offset += nBytesRecvd;
    } else {
        XP_ASSERT( err == SOCKET_ERROR );
        err = WSAGetLastError();
        XP_LOGF( "%s: WSARecv=>%d", __func__, err );
    }

    return nBytesRecvd > 0;
} /* read_from_socket */

/* MSDN: When one of the nominated network events occurs on the specified
   socket s, the application window hWnd receives message wMsg. The wParam
   parameter identifies the socket on which a network event has occurred. The
   low word of lParam specifies the network event that has occurred. The high
   word of lParam contains any error code. The error code be any error as
   defined in Winsock2.h.
 */
XP_Bool
ce_sockwrap_event( CeSocketWrapper* self, WPARAM wParam, LPARAM lParam )
{
    SOCKET socket = (SOCKET)wParam;
    long event = (long)LOWORD(lParam);
    XP_Bool draw = XP_FALSE;

    if ( 0 != (FD_WRITE & event) ) {
        send_packet_if( self );
        event &= ~FD_WRITE;
        XP_LOGF( "%s: got FD_WRITE", __func__ );
    }

    if ( 0 != (FD_READ & event) ) {
        XP_LOGF( "%s: got FD_READ", __func__ );
        if ( read_from_socket( self ) ) {
            draw = dispatch_msgs( self );
        }
        event &= ~FD_READ;
    }

    if ( 0 != (FD_CONNECT & event) ) {
        int err = WSAGETSELECTERROR(lParam);
        XP_LOGF( "%s: got FD_CONNECT; err=%d", __func__, err );
        event &= ~FD_CONNECT;
        if ( 0 == err ) {
            XP_ASSERT( self->socket == -1 || self->socket == socket );
            self->socket = socket;
            stateChanged( self, CE_IPST_CONNECTED );
        } else {
            closeConnection( self );
        }
    }

    if ( 0 != (FD_CLOSE & event) ) {
        event &= ~FD_CLOSE;
        closeConnection( self );
    }

    if ( 0 != event ) {
        XP_WARNF( "%s: unexpected bits left: 0x%lx", __func__, event );
    }
    return draw;
} /* ce_sockwrap_event */

#ifdef _WIN32_WCE
#ifdef DEBUG
static const char*
CMStatus2Str( WPARAM status )
{
#define CASESTR(s)   case (s): return #s
    switch( status ) {
        CASESTR( CONNMGR_STATUS_CONNECTED );
        CASESTR( CONNMGR_STATUS_NOPATHTODESTINATION );
        CASESTR( CONNMGR_STATUS_CONNECTIONCANCELED );
        CASESTR( CONNMGR_STATUS_CONNECTIONLINKFAILED );
        CASESTR( CONNMGR_STATUS_CONNECTIONDISABLED );
        CASESTR( CONNMGR_STATUS_AUTHENTICATIONFAILED );
        CASESTR( CONNMGR_STATUS_PHONEOFF );
        CASESTR( CONNMGR_STATUS_UNKNOWN );
        CASESTR( CONNMGR_STATUS_DISCONNECTED );
        CASESTR( CONNMGR_STATUS_CONNECTIONFAILED );
        CASESTR( CONNMGR_STATUS_WAITINGFORPATH );
        CASESTR( CONNMGR_STATUS_WAITINGFORPHONE );
        CASESTR( CONNMGR_STATUS_EXCLUSIVECONFLICT );
        CASESTR( CONNMGR_STATUS_WAITINGCONNECTION );
        CASESTR( CONNMGR_STATUS_WAITINGFORRESOURCE );
        CASESTR( CONNMGR_STATUS_WAITINGFORNETWORK );
        CASESTR( CONNMGR_STATUS_WAITINGDISCONNECTION );
        CASESTR( CONNMGR_STATUS_WAITINGCONNECTIONABORT );
        CASESTR( CONNMGR_STATUS_NOPATHWITHPROPERTY );
    }
#undef CASESTR
    XP_ASSERT(0);
    return "";
}
#endif

void
ce_connmgr_event( CeSocketWrapper* self, WPARAM wParam, ConnMgrErr* userErr )
{
    XP_LOGF( "%s: wParam=%s", __func__, CMStatus2Str(wParam) );

    *userErr = CONN_ERR_NONE;

    switch( wParam ) {
    case CONNMGR_STATUS_CONNECTED:
        stateChanged( self, CE_IPST_NETWORK_OPENED );
        break;

        /* no recovery from any of these */
    case CONNMGR_STATUS_NOPATHTODESTINATION:
    case CONNMGR_STATUS_CONNECTIONCANCELED:
    case CONNMGR_STATUS_CONNECTIONLINKFAILED:
    case CONNMGR_STATUS_CONNECTIONDISABLED:
    case CONNMGR_STATUS_AUTHENTICATIONFAILED:
        /* Do I want to release, or keep it around for status messages
           later? */
        //(*self->cmProcs->ConnMgrReleaseConnection)( self->connMgrHandle, 1 );
        //self->connMgrHandle = NULL;
        stateChanged( self, CE_IPST_START );
        *userErr = CONN_ERR_NONET;
        break;

        /* Error the user can fix.... */
    case CONNMGR_STATUS_PHONEOFF:
        closeConnection( self );
        *userErr = CONN_ERR_PHONE_OFF;
        break;

    case CONNMGR_STATUS_UNKNOWN:
    case CONNMGR_STATUS_DISCONNECTED:
    case CONNMGR_STATUS_CONNECTIONFAILED:
    case CONNMGR_STATUS_WAITINGFORPATH:
    case CONNMGR_STATUS_WAITINGFORPHONE:
    case CONNMGR_STATUS_EXCLUSIVECONFLICT:
    case CONNMGR_STATUS_WAITINGCONNECTION:
    case CONNMGR_STATUS_WAITINGFORRESOURCE:
    case CONNMGR_STATUS_WAITINGFORNETWORK:
    case CONNMGR_STATUS_WAITINGDISCONNECTION:
    case CONNMGR_STATUS_WAITINGCONNECTIONABORT:
    case CONNMGR_STATUS_NOPATHWITHPROPERTY:
        break;
    default:
        XP_LOGF( "unknown status: %x", wParam );
    }
}
#endif

XP_S16
ce_sockwrap_send( CeSocketWrapper* self, const XP_U8* buf, XP_U16 len, 
                  const CommsAddrRec* addr )
{
    XP_S16 nSent = -1;          /* error */
    XP_LOGF( "%s(len=%d)", __func__, len );

   /* If the address has changed, we need to close the connection, then call
      getHostAddr() to kick off the async reconnect process. */
    XP_ASSERT( addr->conType == COMMS_CONN_RELAY );
    if ( 0 != XP_STRCMP( addr->u.ip_relay.hostName, 
                         self->addrRec.u.ip_relay.hostName )
         || 0 != XP_STRCMP( addr->u.ip_relay.invite, 
                            self->addrRec.u.ip_relay.invite )
         || addr->u.ip_relay.port != self->addrRec.u.ip_relay.port ) {
        closeConnection( self );
        XP_MEMCPY( &self->addrRec, addr, sizeof(self->addrRec) );

    }

    if ( CE_IPST_START == self->connState ) {
#ifdef _WIN32_WCE
        openNetwork( self );    /* kicks off connection process */
#else
        getHostAddr( self );    /* kicks off connection process */
#endif
    }
    /* What if we're stuck in some other state?  Kick those here too? */

    if ( bqAdd( &self->queueOut, buf, len ) ) {
        send_packet_if( self );
        nSent = len;
    } else {
        XP_WARNF( "dropping packet; queue full" );
    }

    LOG_RETURNF( "%d", nSent );
    return nSent;
} /* ce_sockwrap_send */

#endif