/* Copyright (c) 1997-1999 Miller Puckette.
* For information on usage and redistribution, and for a DISCLAIMER OF ALL
* WARRANTIES, see the file, "LICENSE.txt," in this distribution.  */

#ifndef MSW     /* in unix this only works first; in MSW it only works last. */
#include "tk.h"
#endif

#include "t_tk.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <sys/types.h>

#ifndef MSW
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <netdb.h>
#ifdef HAVE_BSTRING_H
#include <bstring.h>
#endif
#include <sys/time.h>
#include <errno.h>
#include <fcntl.h>
#endif
#ifdef MSW
#include <winsock.h>
#include <io.h>
#endif
#ifdef MSW
#pragma warning( disable : 4305 )  /* uncast const double to float */
#pragma warning( disable : 4244 )  /* uncast double to float */
#pragma warning( disable : 4101 )  /* unused local variables */
#endif

#ifdef MSW
#include "tk.h"
#endif

#ifdef MACOSX
#define STARTGUI
#endif

#ifdef __linux__
#define STARTGUI
#endif

#define FIRSTPORTNUM 5600

void tcl_mess(char *s);
static Tcl_Interp *tk_pdinterp;
static int pd_portno = 0;


/***************** the socket setup code ********************/

/* If this is reset by pdgui_setsock(), it's the port number Pd will try to
connect to; but if zero, that means we should set it and start Pd ourselves. */


        /* some installations of linux don't know about "localhost" so give
        the loopback address; NT, on the other hand, can't understand the
        hostname "127.0.0.1". */
char hostname[100] =
#ifdef __linux__
    "127.0.0.1";
#else
    "localhost";
#endif

void pdgui_setsock(int port)
{
    pd_portno = port;
}

    /* why is this here??? probably never used (see t_main.c). */
void pdgui_sethost(char *name)
{
    strncpy(hostname, name, 100);
    hostname[99] = 0;
}

static void pdgui_sockerror(char *s)
{
#ifdef MSW
    int err = WSAGetLastError();
#endif
#ifndef MSW
    int err = errno;
#endif

    fprintf(stderr, "%s: %s (%d)\n", s, strerror(err), err);
    tcl_mess("exit\n");
    exit(1);
}

static int sockfd;

/* The "pd_suck" command, which polls the socket. */

#define CHUNKSIZE 20000 /* chunks to allocate memory for reading socket */
#define READSIZE 10000  /* size of read to issue */

static char *pd_tkbuf = 0;      /* buffer for reading */
static int pd_tkbufsize = 0;    /* current buffer size */
static int pd_tkgotbytes = 0;   /* number of bytes already in buffer */

static void pd_readsocket(ClientData cd, int mask)
{
    int ngot;
    fd_set readset, writeset, exceptset;
    struct timeval timout;

    timout.tv_sec = 0;
    timout.tv_usec = 0;
    FD_ZERO(&writeset);
    FD_ZERO(&readset);
    FD_ZERO(&exceptset);
    FD_SET(sockfd, &readset);
    FD_SET(sockfd, &exceptset);
    if (!pd_tkbuf)
    {
        if (!(pd_tkbuf = malloc(CHUNKSIZE)))
        {
            fprintf(stderr, "pd-gui: out of memory\n");
            tcl_mess("exit\n");
        }
        pd_tkbufsize = CHUNKSIZE;
    }
    if (pd_tkgotbytes + READSIZE + 1 > pd_tkbufsize)
    {   
        int newsize = pd_tkbufsize + CHUNKSIZE;
        char *newbuf = realloc(pd_tkbuf, newsize);
        if (!newbuf)
        {
            fprintf(stderr, "pd-gui: out of memory\n");
            tcl_mess("exit\n");
        }
        pd_tkbuf = newbuf;
        pd_tkbufsize = newsize;     
    }
    if (select(sockfd+1, &readset, &writeset, &exceptset, &timout) < 0)
        perror("select");
    if (FD_ISSET(sockfd, &exceptset) || FD_ISSET(sockfd, &readset))
    {
        int ret;
        ret = recv(sockfd, pd_tkbuf + pd_tkgotbytes, READSIZE, 0);
        if (ret < 0)
            pdgui_sockerror("socket receive error");
        else if (ret == 0)
        {
            /* fprintf(stderr, "read %d\n", SOCKSIZE - pd_tkgotbytes); */
            fprintf(stderr, "pd_gui: pd process exited\n");
            tcl_mess("exit\n");
        }
        else
        {
            char *lastcr = 0, *bp = pd_tkbuf, *ep = bp + (pd_tkgotbytes + ret);
            int brace = 0;
            char lastc = 0;
                /* search for locations that terminate a complete TK
                command.  These are carriage returns which are not inside
                any braces.  Braces can be escaped with backslashes (but
                backslashes themselves can't.) */
            while (bp < ep)
            {
                char c = *bp;
                if (c == '}' && brace)
                    brace--;
                else if (c == '{')
                    brace++;
                else if (!brace && c == '\n' && lastc != '\\')
                    lastcr = bp;
                lastc = c;
                bp++;
            }
                /* if lastcr is set there is at least one complete TK
                command in the buffer.  Execute it or them, and slide any
                extra bytes to beginning of the buffer. */
            if (lastcr)
            {
                int xtra = pd_tkbuf + pd_tkgotbytes + ret - (lastcr+1);
                char bashwas = lastcr[1];
                lastcr[1] = 0;
                tcl_mess(pd_tkbuf);
                lastcr[1] = bashwas;
                if (xtra)
                {
                    /* fprintf(stderr, "x %d\n", xtra); */
                    memmove(pd_tkbuf, lastcr+1, xtra);
                }
                pd_tkgotbytes = xtra;
            }
            else
            {
                pd_tkgotbytes += ret;
            }
        }
    }
}

#ifdef MSW
    /* if we're in Gatesland, we add a tcl command to poll the
    socket for data.  */
static int pd_pollsocketCmd(ClientData cd, Tcl_Interp *interp,
    int argc, char **argv)
{
    pd_readsocket(cd, 0);
    return (TCL_OK);
}
#endif

static void pd_sockerror(char *s)
{
#ifdef MSW
    int err = WSAGetLastError();
    if (err == 10054) return;
    else if (err == 10044)
    {
        fprintf(stderr,
            "Warning: you might not have TCP/IP \"networking\" turned on\n");
        fprintf(stderr, "which is needed for Pd to talk to its GUI layer.\n");
    }
#else
    int err = errno;
#endif
    fprintf(stderr, "%s: %s (%d)\n", s, strerror(err), err);
}

static void pdgui_connecttosocket(void)
{
    struct sockaddr_in server;
    struct hostent *hp;
#ifndef MSW
    int retry = 10;
#else
    int retry = 1;
#endif
#ifdef MSW
    short version = MAKEWORD(2, 0);
    WSADATA nobby;

    if (WSAStartup(version, &nobby)) pdgui_sockerror("setup");
#endif

    /* create a socket */
    sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd < 0) pdgui_sockerror("socket");

    /* connect socket using hostname provided in command line */
    server.sin_family = AF_INET;

    hp = gethostbyname(hostname);

    if (hp == 0)
    {
        fprintf(stderr,
            "localhost not found (inet protocol not installed?)\n");
        exit(1);
    }
    memcpy((char *)&server.sin_addr, (char *)hp->h_addr, hp->h_length);

    /* assign client port number */
    server.sin_port = htons((unsigned short)pd_portno);

        /* try to connect */
    while (1)
    {
        if (connect(sockfd, (struct sockaddr *) &server, sizeof (server)) >= 0)
            goto gotit;
        retry--;
        if (retry <= 0)
            break;
          /* In unix there's a race condition; the child won't be
          able to connect before the parent (pd) has shed its
          setuid-ness.  In case this is the problem, sleep and
          retry. */
        else
        {
#ifndef MSW
            fd_set readset, writeset, exceptset;
            struct timeval timout;

            timout.tv_sec = 0;
            timout.tv_usec = 100000;
            FD_ZERO(&writeset);
            FD_ZERO(&readset);
            FD_ZERO(&exceptset);
            fprintf(stderr, "retrying connect...\n");
            if (select(1, &readset, &writeset, &exceptset, &timout) < 0)
                perror("select");
#endif /* !MSW */
        }
    }
    pdgui_sockerror("connecting stream socket");
gotit: ;
#ifndef MSW
        /* normally we ask TK to call us back; but in MSW we have to poll. */
    Tk_CreateFileHandler(sockfd, TK_READABLE | TK_EXCEPTION,
        pd_readsocket, 0);
#endif /* !MSW */
}

#ifdef STARTGUI

/* #define DEBUGCONNECT */

#ifdef DEBUGCONNECT
static FILE *debugfd;
#endif


static void pd_startfromgui( void)
{
    pid_t childpid;
    char cmdbuf[1000], pdbuf[1000], *lastchar;
    const char *arg0;
    struct sockaddr_in server;
    int msgsock;
    int len = sizeof(server), nchar;
    int ntry = 0, portno = FIRSTPORTNUM;
    int xsock = -1;
    char morebuf[256];
#ifdef MSW
    short version = MAKEWORD(2, 0);
    WSADATA nobby;
    char scriptbuf[1000], wishbuf[1000], portbuf[80];
    int spawnret;
    char intarg;
#else
    int intarg;
#endif

    arg0 = Tcl_GetVar(tk_pdinterp, "argv0", 0);
    if (!arg0)
    {
        fprintf(stderr, "Pd-gui: can't get arg 0\n");
        return;
    }
    lastchar = strrchr(arg0, '/');
    if (lastchar)
        snprintf(pdbuf, lastchar - arg0 + 1, "%s", arg0);
    else strcpy(pdbuf, ".");
    strcat(pdbuf, "/../bin/pd");
#ifdef DEBUGCONNECT     
    fprintf(stderr, "pdbuf is %s\n", pdbuf);
#endif

#ifdef MSW
    if (WSAStartup(version, &nobby))
        pd_sockerror("WSAstartup");
#endif

    /* create a socket */
    xsock = socket(AF_INET, SOCK_STREAM, 0);
    if (xsock < 0) pd_sockerror("socket");
    intarg = 1;
    if (setsockopt(xsock, IPPROTO_TCP, TCP_NODELAY,
        &intarg, sizeof(intarg)) < 0)
            fprintf(stderr, "setsockopt (TCP_NODELAY) failed\n");

    server.sin_family = AF_INET;
    server.sin_addr.s_addr = INADDR_ANY;

    /* assign server port number */
    server.sin_port =  htons((unsigned short)portno);

        /* name the socket */
    while (bind(xsock, (struct sockaddr *)&server, sizeof(server)) < 0)
    {
#ifdef MSW
        int err = WSAGetLastError();
#else
        int err = errno;
#endif
        if ((ntry++ > 20) || (err != EADDRINUSE))
        {
            perror("bind");
            fprintf(stderr,
                "couldn't open GUI-to-pd network connection\n");
            return;
        }
        portno++;
        server.sin_port = htons((unsigned short)(portno));
    }

#ifdef DEBUGCONNECT     
    fprintf(debugfd, "port %d\n", portno);
        fflush(debugfd);
#endif

#ifdef UNISTD
    childpid = fork();
    if (childpid < 0)
    {
        if (errno) perror("sys_startgui");
        else fprintf(stderr, "sys_startgui failed\n");
        return;
    }
    else if (!childpid)                 /* we're the child */
    {
        sprintf(cmdbuf, "\"%s\" -guiport %d\n", pdbuf, portno);
#ifdef DEBUGCONNECT     
        fprintf(debugfd, "%s", cmdbuf);
        fflush(debugfd);
#endif
        execl("/bin/sh", "sh", "-c", cmdbuf, 0);
        perror("pd: exec");
        _exit(1);
    }
#endif /* UNISTD */

#ifdef MSW       

#error not yet used.... sys_bashfilename() not filled in here

    strcpy(cmdbuf, pdcmd);
    strcat(cmdbuf, "/pd.exe");
    sys_bashfilename(scriptbuf, scriptbuf);

    sprintf(portbuf, "%d", portno);

    spawnret = _spawnl(P_NOWAIT, cmdbuf, "pd.exe", "-port", portbuf, 0);
    if (spawnret < 0)
    {
        perror("spawnl");
        fprintf(stderr, "%s: couldn't start\n", cmdbuf);
        return;
    }

#endif /* MSW */

#ifdef DEBUGCONNECT
        fprintf(stderr, "Waiting for connection request... \n");
#endif
    if (listen(xsock, 5) < 0) pd_sockerror("listen");
    sockfd = accept(xsock, (struct sockaddr *) &server, (unsigned int *)&len);
    if (sockfd < 0) pd_sockerror("accept");
#ifdef DEBUGCONNECT
        fprintf(stderr, "... connected\n");
#endif

#ifndef MSW
        /* normally we ask TK to call us back; but in MSW we have to poll. */
    Tk_CreateFileHandler(sockfd, TK_READABLE | TK_EXCEPTION,
        pd_readsocket, 0);
#endif /* !MSW */
}

#endif /* STARTGUI */

static void pdgui_setupsocket(void)
{
#ifdef DEBUGCONNECT
        debugfd = fopen("/Users/msp/bratwurst", "w");
        fprintf(debugfd, "turning stderr back on\n");
        fflush(debugfd);
        dup2(fileno(debugfd), 2);
        fprintf(stderr, "duped to stderr?\n");
#endif
#ifdef MSW
        pdgui_connecttosocket();
#else
    if (pd_portno)
        pdgui_connecttosocket();
    else pd_startfromgui() ;
#endif
}

/**************************** commands ************************/
static char *pdgui_path;

/* The "pd" command, which cats its args together and throws the result
* at the Pd interpreter.
*/
#define MAXWRITE 1024

static int pdCmd(ClientData cd, Tcl_Interp *interp, int argc,  char **argv)
{
    if (argc == 2)
    {
        int n = strlen(argv[1]);
        if (send(sockfd, argv[1], n, 0) < n)
        {
            perror("stdout");
            tcl_mess("exit\n");
        }
    }
    else
    {
        int i;
        char buf[MAXWRITE];
        buf[0] = 0;
        for (i = 1; i < argc; i++)
        {
            if (strlen(argv[i]) + strlen(buf) + 2 > MAXWRITE)
            {
                interp->result = "pd: arg list too long";
                return (TCL_ERROR);     
            }
            if (i > 1) strcat(buf, " ");
            strcat(buf, argv[i]);
        }
        if (send(sockfd, buf, strlen(buf), 0) < 0)
        {
            perror("stdout");
            tcl_mess("exit\n");
        }
    }
    return (TCL_OK);
}

/***********  "c" level access to tk functions. ******************/

void tcl_mess(char *s)
{
    int result;
    result = Tcl_Eval(tk_pdinterp,  s);
    if (result != TCL_OK)
    {
        if (*tk_pdinterp->result) printf("%s\n",  tk_pdinterp->result);
    }
}

    /* in linux, we load the tk code from here (in MSW and MACOS, this
    is done by passing the name of the file as a startup argument to
    the wish shell.) */
#if !defined(MSW) && !defined(MACOSX)
void pdgui_doevalfile(Tcl_Interp *interp, char *s)
{
    char buf[GUISTRING];
    sprintf(buf, "set pd_guidir \"%s\"\n", pdgui_path);
    tcl_mess(buf);
    strcpy(buf, pdgui_path);
    strcat(buf, "/bin/");
    strcat(buf, s);
    if (Tcl_EvalFile(interp, buf) != TCL_OK)
    {
        char buf2[1000];
        sprintf(buf2, "puts [concat tcl: %s: can't open script]\n",
            buf);
        tcl_mess(buf2);
    }
}

void pdgui_evalfile(char *s)
{
    pdgui_doevalfile(tk_pdinterp, s);
}
#endif

void pdgui_startup(Tcl_Interp *interp)
{
        /* save pointer to the main interpreter */
    tk_pdinterp = interp;

        /* add our own TK commands */
    Tcl_CreateCommand(interp, "pd",  (Tcl_CmdProc*)pdCmd, (ClientData)NULL, 
        (Tcl_CmdDeleteProc *)NULL); 
#ifdef MSW
    Tcl_CreateCommand(interp, "pd_pollsocket",(Tcl_CmdProc*)  pd_pollsocketCmd,
        (ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);
#endif
    pdgui_setupsocket();
        /* read in the startup file */
#if !defined(MSW) && !defined(MACOSX)
    pdgui_evalfile("pd.tk");
#endif
}

#ifndef MSW
void pdgui_setname(char *s)
{
    char *t;
    char *str;
    int n;
    if (t = strrchr(s, '/')) str = s, n = (t-s) + 1;
    else str = "./", n = 2;
    if (n > GUISTRING-100) n = GUISTRING-100;
    pdgui_path = malloc(n+9);

    strncpy(pdgui_path, str, n);
    while (strlen(pdgui_path) > 0 && pdgui_path[strlen(pdgui_path)-1] == '/')
        pdgui_path[strlen(pdgui_path)-1] = 0;
    if (t = strrchr(pdgui_path, '/'))
        *t = 0;
}
#endif

    /* this is called when an off-the-shelf "wish" has to "load" this module
    at runtime.  In Linux, this module is linked in and Pdtcl_Init() is not
    called; instead, the code in t_main.c calls pdgui_setsock() and
    pdgui_startup(). */ 

int Pdtcl_Init(Tcl_Interp *interp)
{
    const char *argv = Tcl_GetVar(interp, "argv", 0);
    int portno, argno = 0;
    if (argv && (portno = atoi(argv)) > 1)
        pdgui_setsock(portno);
    tk_pdinterp = interp;
    pdgui_startup(interp);
    interp->result = "loaded pdtcl_init";

    return (TCL_OK);
}

#if 0
int Pdtcl_SafeInit(Tcl_Interp *interp) {
    fprintf(stderr, "Pdtcl_Safeinit 51\n");
        return (TCL_OK);
}
#endif