#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <ctype.h>
#include <misc.h>
#include <pwd.h>
#include "pppdialin.h"
#include "pppdialin.m"
#include "../../paths.h"
#include <module_apis/fwinfo_apidef.h>
#include <netconf.h>

static HELP_FILE help_ipup ("pppdialin","ip-up");
extern HELP_FILE help_dialin;

static const char ppp_dialout[]="dialout";
static const char ppppostcon[]="/usr/lib/linuxconf/lib/ppppostlogin";
static const char ppppostdis[]="/usr/lib/linuxconf/lib/ppppostlogout";

static CONFIG_FILE f_ipup (ETC_PPP_IPUP
	,help_ipup
	,CONFIGF_MANAGED|CONFIGF_OPTIONAL
	,"root","root",0755,ppp_dialout);
static CONFIG_FILE f_ipdown (ETC_PPP_IPDOWN
	,help_ipup
	,CONFIGF_MANAGED|CONFIGF_OPTIONAL
	,"root","root",0755,ppp_dialout);

/*
	Make sure the config file has one call to the script
*/
static bool ipupupd_checkone(
	CONFIG_FILE &cf,
	const char *script,
	bool doit)
{
	bool ret = false;
	FILE_CFG *fin = cf.fopen ("r");
	if (fin != NULL){
		char buf[1000];
		int len = strlen(script);
		bool first = true;
		bool copy_sh = false;
		while (fgets(buf,sizeof(buf)-1,fin)!=NULL){
			strip_end (buf);
			if (first){
				if (strcmp(buf,"#!/bin/sh")==0 
					|| strcmp(buf,"#!/bin/bash")==0){
					copy_sh = true;
				}
				first = false;
			}
			if (strncmp(buf,script,len)==0 && isspace(buf[len])){
				ret = true;
				break;
			}
		}
		if (!ret && doit){
			/* #Specification: pppdialin / updating ip-up ip-down
				We must register a script in that file, but we can't
				put it at the end because some scripts ends with "exit 0".
				So we put it at the beginning, after the #!/bin/sh if
				there.
			*/
			const char *cfpath = cf.getpath();
			char pathnew[PATH_MAX];
			snprintf (pathnew,sizeof(pathnew)-1,"%s.NEW",cfpath);
			FILE_CFG *fout = cf.fopen (pathnew,"w");
			if (fout != NULL){
				rewind (fin);
				if (copy_sh){
					if (fgets(buf,sizeof(buf)-1,fin)!=NULL) fputs (buf,fout);
				}
				fprintf (fout,"%s \"$@\"\n",script);
				while (fgets(buf,sizeof(buf)-1,fin)!=NULL) fputs (buf,fout);
				if (fclose (fout)!=-1){
					char pathbak[PATH_MAX];
					snprintf (pathbak,sizeof(pathbak)-1,"%s.BAK",cfpath);
					rename (cfpath,pathbak);
					rename (pathnew,cfpath);
				}
			}
		}
		fclose (fin);
	}else if (doit){
		FILE_CFG *fout = cf.fopen ("w");
		if (fout != NULL){
			fprintf (fout,"#!/bin/sh\n");
			fprintf (fout,"%s \"$@\"\n",script);
			fclose (fout);
		}
	}
	return ret;
}

void ipupupd_check()
{
	if (!ipupupd_checkone (f_ipup,ppppostcon,false)
		|| !ipupupd_checkone (f_ipdown,ppppostdis,false)){
		if (dialog_yesno (MSG_U(T_MODIPUP,"Modify ip-up/ip-down")
			,MSG_U(I_MODIPUP
				,"The files /etc/ppp/ip-up and /etc/ppp/ip-down\n"
				 "must be modified to support the pppdialin module\n"
				 "\n"
				 "The following lines must be added respectivly to\n"
				 "each file:\n"
				 "\n"
				 "ip-up  : /usr/lib/linuxconf/lib/ppppostlogin \"$@\"\n"
				 "ip-down: /usr/lib/linuxconf/lib/ppppostlogout \"$@\"\n"
				 "\n"
				 "Do you want to do it ?")
			,help_dialin)==MENU_YES){
			ipupupd_checkone (f_ipup,ppppostcon,true);
			ipupupd_checkone (f_ipdown,ppppostdis,true);
		}
	}
}

static bool ipupupd_devexist (const char *devname)
{
	bool ret = false;
	if (strncmp(devname,"pppdialin/",10)==0){
		devname += 10;
		struct passwd *p = getpwnam(devname);
		ret = p != NULL;
	}
	return ret;
}

static int ipupupd_getdevlist  (SSTRINGS &devs, SSTRINGS &descs)
{
	devs.add (new SSTRING("pppdialin/account"));
	descs.add (new SSTRING(MSG_U(I_PPPDEV,"One PPP account")));
	return 1;
}

static int pppcon_readpid(const char *path)
{
	int ret = -1;
	FILE *fin = fopen (path,"r");
	if (fin != NULL){
		int pid;
		if (fscanf (fin,"%d",&pid)==1) ret = pid;
		fclose (fin);
	}
	return ret;
}

/*
	Return the PID and the PPP device of the pppd process owned by a ppp account
	Return -1 if the connection is not active.
*/
static int ipupupd_getinfo  (const char *user, SSTRING &kerneldev)
{
	int ret = -1;
	char pathdev[PATH_MAX];
	snprintf (pathdev,sizeof(pathdev)-1,"/var/run/pppdialin.%s",user);
	FILE *fin = fopen (pathdev,"r");
	if (fin != NULL){
		char dev[100];
		if (fscanf (fin,"%s\n",dev)==1){
			char pathpid[PATH_MAX];
			sprintf (pathpid,"/var/run/%s.pid",dev);
			kerneldev.setfrom (dev);
			ret = pppcon_readpid (pathpid);
		}
		fclose (fin);
	}
	if (ret != -1 && kill(ret,0)==-1) ret = -1;
	return ret;
}

int ipupupd_disconnect (const char *user)
{
	int ret = -1;
	SSTRING dev;
	int pid = ipupupd_getinfo(user,dev);
	if (pid != -1){
		ret = kill (pid,SIGTERM);
	}
	return ret;
}
	

static int ipupupd_getdevinfo  (const char *devname, SSTRINGS &kerneldevs)
{
	int ret = -1;
	if (strncmp(devname,"pppdialin/",10)==0){
		SSTRING kerneldev;
		ret = ipupupd_getinfo (devname+10,kerneldev);
		if (ret != -1){
			kerneldevs.add (new SSTRING(kerneldev));
		}
	}
	return ret;
}

// THe dialout module does not define any logical HOST
static bool ipupupd_hostexist (const char *hostname)
{
	return ipupupd_devexist (hostname);
}

static int ipupupd_gethostlist  (SSTRINGS &hosts, SSTRINGS &descs)
{
	return ipupupd_getdevlist (hosts,descs);
}
static int ipupupd_gethostinfo  (const char *host, SSTRINGS &ips)
{
	int ret = -1;
	SSTRINGS devs;
	if (ipupupd_getdevinfo(host,devs)!=-1){
		// We need the IP number associated with the device
		IFCONFIG_INFO info;
		const char *dev = devs.getitem(0)->get();
		if (ifconfig_getinfo_nocheck(dev,info)!=-1){
			ips.add (new SSTRING(info.ip_addr));
			ret = 0;
		}
	}
	return ret;
}

void *ipupupd_fwinfo_api_get()
{
	FWINFO_API *api = new FWINFO_API;
	api->devexist    = ipupupd_devexist;
	api->getdevlist  = ipupupd_getdevlist;
	api->getdevinfo  = ipupupd_getdevinfo;
	api->hostexist   = ipupupd_hostexist;
	api->gethostlist = ipupupd_gethostlist;
	api->gethostinfo = ipupupd_gethostinfo;
	return api;
}

void ipupupd_fwinfo_api_release(void *api)
{
	delete (FWINFO_API*)api;
}