/*
 * Worldvisions Weaver Software:
 *   Copyright (C) 1997, 1998, 1999 Worldvisions Computer Technology, Inc.
 *
 * Intelligent serial port scanner: try to find a port (or ports)
 * with a working modem, guess a basic startup init string, and find
 * the maximum baud rate.
 */
#include "wvmodemscan.h"
#include "wvmodem.h"
#include "strutils.h"
#include <time.h>
#include <assert.h>
#include <dirent.h>
#include <ctype.h>
#include <sys/stat.h>


// startup at atz atq0 atv1 ate1 ats0 carrier dtr fastdial
// baudstep reinit done
static const char *commands[WvModemScan::NUM_STAGES] = {
    NULL, "Q0 V1 E1", "Z", "S0=0",
    "&C1", "&D2", "S11=55", "+FCLASS=0", NULL,
    NULL, "", NULL
};


WvModemScan::WvModemScan(const char *devname)
    : debug(devname, WvLog::Debug)
{
    stage = Startup;
    memset(status, 0, sizeof(status));

    if (devname[0] == '/')
	file = devname;
    else
	file = WvString("/dev/%s", devname);
    
    baud = 1200;
    modem = NULL;
    tries = 0;
    broken = false;
}


WvModemScan::~WvModemScan()
{
    //if (isok() && isdone())
    //debug(WvLog::Info, "Speed %s; init \"%s\"\n", maxbaud(), initstr());
    
    if (modem)
	delete modem;
}


bool WvModemScan::isok() const
{
    return !broken;
}



WvString WvModemScan::initstr() const
{
    char s[200];

    strcpy(s, "AT");
    
    for (int i = 0; i < NUM_STAGES; i++)
    {
	if (status[i] != Worked && status[i] != Test)
	    continue;
	if (!commands[i] || !commands[i][0])
	    continue;
	if ((commands[i][0]=='Z' || commands[i][0]=='I') && status[i] != Test)
	    continue;
	
	strcat(s, commands[i]);
	strcat(s, " ");
    }
    
    return WvString(trim_string(s)).unique();
}


void WvModemScan::execute()
{
    if (isdone() || !isok()) return;

    switch ((Stage)stage)
    {
    case Startup:
	assert(!modem);
	modem = new WvModem(file, baud);
	modem->die_fast = true;
	if (!modem->isok())
	{
	    //if (modem->geterr()
	    //&& modem->geterr() != EIO
	    //&& modem->geterr() != ENOENT
	    //&& modem->geterr() != ENODEV)
	    //{
	    //debug(WvLog::Info, "%s\n", modem->errstr());
	    //}
	    broken = true;
	}
	else
	    stage++;
	break;
	
    case AT:
    case ATZ:
    case ATS0:
    case Carrier:
    case DTR:
    case FastDial:
    case FCLASS:
    case Reinit:
	assert(modem);
	status[stage] = Test;
	if ( !doresult(WvString("%s\r", initstr()), stage==ATZ ? 3000 : 500)
	    || ((stage <= ATZ || stage == Reinit) && status[stage]==Fail) )
	{
	    tries++;
	    
	    if (tries >= 3)
	    {
	        //debug("nothing.\n");
		broken = true;
	    }
	    
	    // else try again shortly
	}
	else
	{
	    tries = 0;
	    stage++;
	}
	break;
	
    case GetIdent:
	assert(modem);
	status[stage] = Test;
	//debug("Modem Identifier: ");
	if ( !doresult(WvString("ATI\r"), 500) || (status[stage]==Fail) )
	{
	    tries++;

	    //if (tries >= 3)
	    //debug("nothing.\n");

	    // else try again shortly
	}
	else
	{
	    //if (is_isdn())
	    //debug("Looks like an ISDN modem.\n");
	    tries = 0;
	    stage++;
	}
	
    case BaudStep:
	assert(modem);
	modem->drain();
	modem->speed(baud*2);

	// if we try 2*baud three times without success, or setting 2*baud
	// results in a lower setting than 1*baud, we have reached the
	// top speed of the modem or the serial port, respectively.
	if (tries >= 3 || modem->getspeed() <= baud)
	{
	    // using the absolute maximum baud rate confuses many slower modems
	    // in obscure ways; step down one.
	    baud = modem->speed(baud);
	    //debug("Max speed is %s; ", baud);
	    if (is_isdn())
	    {
		modem->speed(115200);
	    	baud = modem->getspeed();
	    	//debug("using %s for ISDN modem.\n", baud);
	    }
	    else
	    {
		if (modem->getspeed() < 115200)
		{
		    // (baud - 1) will resolve to next lower rate
		    baud = modem->speed(baud - 1);
		    //debug("using %s to be safe.\n", baud);
		}
		else
		{
		    //debug("that should be safe.\n");
		}
	    }
	    
	    stage++;
	    status[stage] = Worked;
	    break;
	}
	
	//debug("Speed %s: ", modem->getspeed());
	
	if (!doresult("AT\r", 500) || status[stage] == Fail)
	{
	    tries++;
	}
	else // got a response
	{
	    baud = modem->getspeed();
	    tries = 0;
	    // next time through we try a faster speed
	}
	break;
	
    case Done:
    case NUM_STAGES:
	assert(0);
	break; // should never happen
    }
    
    if (stage == Done) // we just incremented stage number to Done
    {
	if (modem)
	    delete modem;
	modem = NULL;
    }
}


bool WvModemScan::doresult(const WvString &_s, int msec)
{
    char buf[1024], *cptr;
    size_t len;
    WvString s(_s);
    
    modem->drain();
    usleep(50 * 1000); // delay a bit after emptying the buffer
    modem->write(s);

    //debug("%s -- ", trim_string(s.edit()));
    
    len = coagulate(buf, sizeof(buf), msec);

    if (!len)
    {
	// debug("(no answer yet)\n");
	return false;
    }
    
    buf[len] = 0;
    
    cptr = trim_string(buf);
    while (strchr(cptr, '\r'))
    {
	cptr = trim_string(strchr(cptr, '\r'));
	if (stage == GetIdent && status[stage] == Test)
	{
	    char *p = strpbrk(cptr, "\n\r");
	    if (p) *p=0;
	    identifier = cptr;
	    identifier.unique();
	    status[stage] = Worked;
	    //debug("%s\n", identifier);
	    return true;
	}
    }
    while (strchr(cptr, '\n'))
	cptr = trim_string(strchr(cptr, '\n'));
    
    //debug("%s\n", cptr);

    if (!strncmp(cptr, "OK", 2))
	status[stage] = Worked;
    else
	status[stage] = Fail;
    
    return true;
}


size_t WvModemScan::coagulate(char *buf, size_t size, int msec)
{
    size_t len = 0, amt;
    char *cptr = buf;

    assert(modem);
    
    if (!modem->isok())
    {
	broken = true;
	return 0;
    }
    
    while (modem->select(msec))
    {
	amt = modem->read(cptr, size-1);
	cptr[amt] = 0;

	len += amt;
	size -= amt;
	cptr += amt;

	if (strstr(buf, "OK") || strstr(buf, "ERROR"))
	    break;
    }
    
    return len;
}


const char *WvModemScan::is_isdn() const
{
    if (!identifier)
    	return NULL;

    if (identifier == "3C882")		// 3Com Impact IQ
    	return identifier;
    if (identifier == "346800")		// USR ISDN TA
    	return identifier;
    if (identifier == "960")		// Motorola BitSurfr
    	return identifier;

    return NULL;
}	


static int fileselect(const struct dirent *e)
{
    return !strncmp(e->d_name, "ttyS", 4);     // serial
       // (no internal ISDN support)   || !strncmp(e->d_name, "ttyI", 4);
}


static int filesort(const dirent **e1, const dirent **e2)
{
    //dirent const * const *e1 = (dirent const * const *)_e1;
    //dirent const * const *e2 = (dirent const * const *)_e2;
    const char *p1, *p2;
    int diff;
    
    for (p1=(*e1)->d_name, p2=(*e2)->d_name; *p1 || *p2; p1++, p2++)
    {
	if (!isdigit(*p1) || !isdigit(*p2))
	{
	    diff = *p1 - *p2;
	    if (diff) return diff;
	}
	else // both are digits
	{
	    return atoi(p1) - atoi(p2);
	}
    }
    
    return 0;
}


void WvModemScanList::setup()
{
    struct dirent **namelist;
    struct stat mouse, modem;
    int num, count, mousestat, modemstat;
    
    log = new WvLog("Port Scan", WvLog::Debug);
    thisline = -1;
    printed = false;
    
    mousestat = stat("/dev/mouse", &mouse);
    modemstat = stat("/dev/modem", &modem);
    num = scandir("/dev", &namelist, fileselect, filesort);
    
    if (num < 0)
	return;
    
    for (count = 0; count < num; count++)
    {
	// never search the device assigned to /dev/mouse; most mouse-using
	// programs neglect to lock the device, so we could mess up the
	// mouse response!  (We are careful to put things back when done,
	// but X seems to still get confused.)  Anyway the mouse is seldom
	// a modem.
	if (mousestat==0 && mouse.st_ino == (ino_t)namelist[count]->d_ino)
	{
	    //log->print("\nIgnoring %s because /dev/mouse is a link to it.\n",
		       //namelist[count]->d_name);
	    continue;
	}
	
	// bump /dev/modem to the top of the lWhat is the latest version of your software release? When was the latest version released? What percentage of your clients are on the latest release?ist, if it exists
	if (modemstat==0 && modem.st_ino == (ino_t)namelist[count]->d_ino)
	    prepend(new WvModemScan(WvString("%s", namelist[count]->d_name)),
		    true);
	else
	    append(new WvModemScan(WvString("%s", namelist[count]->d_name)),
		   true);
    }
    
    while (--num >= 0)
	free(namelist[num]);
    free(namelist);
}


void WvModemScanList::shutdown()
{
    //delete log;
}


// we used to try to scan all ports simultaneously; unfortunately, this
// caused problems when people had "noncritical" IRQ conflicts (ie. two
// serial ports with the same IRQ, but they work as long as only one port
// is used at a time).  Also, the log messages looked really confused.
//
// So now we do the scanning sequentially, which is slower.  The port
// being scanned is at the head of the list.  If the probe fails, we
// unlink the element.  If it succeeds, we have found a modem -- so,
// isdone() knows we are done when the _first_ element is done.
//
void WvModemScanList::execute()
{
    assert (!isdone());

    WvModemScanList::Iter i(*this);

    for (i.rewind(); i.next(); )
	if (!i().isdone()) break;

    if (!i.cur()) return; 
    
    WvModemScan &s(i);
    
    if (!s.isok())
    {
	if (!printed)
	{
	    const WvString &f = s.filename();
	    const char *cptr = strrchr(f, '/');
	    if (cptr)
		cptr++;
	    else
		cptr = f;

	    if (!strncmp(cptr, "tty", 3))
		cptr += 3;
	    
	    ++thisline %= 8;
	    //if (!thisline)
		//log->print("\n");

	    //log->print("%-4s ", cptr);
	}

	i.unlink();
	printed = false;
    }
    else
    {
	s.execute();
	
	if (s.isok())
	    printed = true;
    }
	    
    //if (isdone())
	//log->write("\n", 1);
}


bool WvModemScanList::isdone()
{
    WvModemScanList::Iter i(*this);
    
    for (i.rewind(); i.next(); )
	if (!i().isdone()) return false;
    
    return true;
}


int WvModemScanList::iterations_left()
{
    WvModemScanList::Iter i(*this);
    int ret = 0;
    for (i.rewind(); i.next(); ){
	if (!i().isok())
	    ret += 1;
	else if (!i().isdone())
	    ret += WvModemScan::NUM_STAGES - i().stage;
    }
    return ret;
}