/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2002, Christos Ricudis
 *
 * Christos Ricudis <ricudis@itc.auth.gr>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Connect to festival
 *
 * \author Christos Ricudis <ricudis@itc.auth.gr>
 * 
 * \ingroup applications
 */

/*** MODULEINFO
	<depend>working_fork</depend>
 ***/

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include <sys/types.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <ctype.h>
#include <errno.h>
#ifdef HAVE_CAP
#include <sys/capability.h>
#endif /* HAVE_CAP */

#include "asterisk/file.h"
#include "asterisk/logger.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/module.h"
#include "asterisk/md5.h"
#include "asterisk/config.h"
#include "asterisk/utils.h"
#include "asterisk/lock.h"
#include "asterisk/options.h"

#define FESTIVAL_CONFIG "festival.conf"

static char *app = "Festival";

static char *synopsis = "Say text to the user";

static char *descrip = 
"  Festival(text[|intkeys]):  Connect to Festival, send the argument, get back the waveform,"
"play it to the user, allowing any given interrupt keys to immediately terminate and return\n"
"the value, or 'any' to allow any number back (useful in dialplan)\n";


static char *socket_receive_file_to_buff(int fd,int *size)
{
    /* Receive file (probably a waveform file) from socket using   */
    /* Festival key stuff technique, but long winded I know, sorry */
    /* but will receive any file without closeing the stream or    */
    /* using OOB data                                              */
    static char *file_stuff_key = "ft_StUfF_key"; /* must == Festival's key */
    char *buff;
    int bufflen;
    int n,k,i;
    char c;

    bufflen = 1024;
    if (!(buff = ast_malloc(bufflen)))
    {
        /* TODO: Handle memory allocation failure */
    }
    *size=0;

    for (k=0; file_stuff_key[k] != '\0';)
    {
        n = read(fd,&c,1);
        if (n==0) break;  /* hit stream eof before end of file */
        if ((*size)+k+1 >= bufflen)
        {   /* +1 so you can add a NULL if you want */
            bufflen += bufflen/4;
            if (!(buff = ast_realloc(buff, bufflen)))
            {
                /* TODO: Handle memory allocation failure */
            }
        }
        if (file_stuff_key[k] == c)
            k++;
        else if ((c == 'X') && (file_stuff_key[k+1] == '\0'))
        {   /* It looked like the key but wasn't */
            for (i=0; i < k; i++,(*size)++)
                buff[*size] = file_stuff_key[i];
            k=0;
            /* omit the stuffed 'X' */
        }
        else
        {
            for (i=0; i < k; i++,(*size)++)
                buff[*size] = file_stuff_key[i];
            k=0;
            buff[*size] = c;
            (*size)++;
        }

    }

    return buff;
}

static int send_waveform_to_fd(char *waveform, int length, int fd) {

        int res;
        int x;
#ifdef __PPC__ 
	char c;
#endif
	sigset_t fullset, oldset;
#ifdef HAVE_CAP
	cap_t cap;
#endif

	sigfillset(&fullset);
	pthread_sigmask(SIG_BLOCK, &fullset, &oldset);

	res = fork();
	if (res < 0)
		ast_log(LOG_WARNING, "Fork failed\n");
	if (res) {
		pthread_sigmask(SIG_SETMASK, &oldset, NULL);
		return res;
	}
#ifdef HAVE_CAP
	cap = cap_from_text("cap_net_admin-eip");

	if (cap_set_proc(cap)) {
		/* Careful with order! Logging cannot happen after we close FDs */
		ast_log(LOG_WARNING, "Unable to remove capabilities.\n");
	}
	cap_free(cap);
#endif
	for (x=0;x<256;x++) {
		if (x != fd)
			close(x);
	}
	if (ast_opt_high_priority)
		ast_set_priority(0);
	signal(SIGPIPE, SIG_DFL);
	pthread_sigmask(SIG_UNBLOCK, &fullset, NULL);
/*IAS */
#ifdef __PPC__  
	for( x=0; x<length; x+=2)
	{
		c = *(waveform+x+1);
		*(waveform+x+1)=*(waveform+x);
		*(waveform+x)=c;
	}
#endif
	
	if (write(fd,waveform,length) < 0) {
		ast_log(LOG_WARNING, "write() failed: %s\n", strerror(errno));
	}
	close(fd);
	exit(0);
}


static int send_waveform_to_channel(struct ast_channel *chan, char *waveform, int length, char *intkeys) {
	int res=0;
	int fds[2];
	int ms = -1;
	int pid = -1;
	int needed = 0;
	int owriteformat;
	struct ast_frame *f;
	struct myframe {
		struct ast_frame f;
		char offset[AST_FRIENDLY_OFFSET];
		char frdata[2048];
	} myf = {
		.f = { 0, },
	};
	
        if (pipe(fds)) {
                 ast_log(LOG_WARNING, "Unable to create pipe\n");
        	return -1;
        }
	                                                
	/* Answer if it's not already going */
	if (chan->_state != AST_STATE_UP)
		ast_answer(chan);
	ast_stopstream(chan);
	ast_indicate(chan, -1);
	
	owriteformat = chan->writeformat;
	res = ast_set_write_format(chan, AST_FORMAT_SLINEAR);
	if (res < 0) {
		ast_log(LOG_WARNING, "Unable to set write format to signed linear\n");
		return -1;
	}
	
	res=send_waveform_to_fd(waveform,length,fds[1]);
	if (res >= 0) {
		pid = res;
		/* Order is important -- there's almost always going to be mp3...  we want to prioritize the
		   user */
		for (;;) {
			ms = 1000;
			res = ast_waitfor(chan, ms);
			if (res < 1) {
				res = -1;
				break;
			}
			f = ast_read(chan);
			if (!f) {
				ast_log(LOG_WARNING, "Null frame == hangup() detected\n");
				res = -1;
				break;
			}
			if (f->frametype == AST_FRAME_DTMF) {
				ast_log(LOG_DEBUG, "User pressed a key\n");
				if (intkeys && strchr(intkeys, f->subclass)) {
					res = f->subclass;
					ast_frfree(f);
					break;
				}
			}
			if (f->frametype == AST_FRAME_VOICE) {
				/* Treat as a generator */
				needed = f->samples * 2;
				if (needed > sizeof(myf.frdata)) {
					ast_log(LOG_WARNING, "Only able to deliver %d of %d requested samples\n",
						(int)sizeof(myf.frdata) / 2, needed/2);
					needed = sizeof(myf.frdata);
				}
				res = read(fds[0], myf.frdata, needed);
				if (res > 0) {
					myf.f.frametype = AST_FRAME_VOICE;
					myf.f.subclass = AST_FORMAT_SLINEAR;
					myf.f.datalen = res;
					myf.f.samples = res / 2;
					myf.f.offset = AST_FRIENDLY_OFFSET;
					myf.f.src = __PRETTY_FUNCTION__;
					myf.f.data = myf.frdata;
					if (ast_write(chan, &myf.f) < 0) {
						res = -1;
						ast_frfree(f);
						break;
					}
					if (res < needed) { /* last frame */
						ast_log(LOG_DEBUG, "Last frame\n");
						res=0;
						ast_frfree(f);
						break;
					}
				} else {
					ast_log(LOG_DEBUG, "No more waveform\n");
					res = 0;
				}
			}
			ast_frfree(f);
		}
	}
	close(fds[0]);
	close(fds[1]);

/*	if (pid > -1) */
/*		kill(pid, SIGKILL); */
	if (!res && owriteformat)
		ast_set_write_format(chan, owriteformat);
	return res;
}

#define MAXLEN 180
#define MAXFESTLEN 2048




static int festival_exec(struct ast_channel *chan, void *vdata)
{
	int usecache;
	int res=0;
	struct ast_module_user *u;
 	struct sockaddr_in serv_addr;
	struct hostent *serverhost;
	struct ast_hostent ahp;
	int fd;
	FILE *fs;
	const char *host;
	const char *cachedir;
	const char *temp;
	const char *festivalcommand;
	int port=1314;
	int n;
	char ack[4];
	char *waveform;
	int filesize;
	int wave;
	char bigstring[MAXFESTLEN];
	int i;
	struct MD5Context md5ctx;
	unsigned char MD5Res[16];
	char MD5Hex[33] = "";
	char koko[4] = "";
	char cachefile[MAXFESTLEN]="";
	int readcache=0;
	int writecache=0;
	int strln;
	int fdesc = -1;
	char buffer[16384];
	int seekpos = 0;	
	char *data;	
	char *intstr;
	struct ast_config *cfg;
	char *newfestivalcommand;

	if (ast_strlen_zero(vdata)) {
		ast_log(LOG_WARNING, "festival requires an argument (text)\n");
		return -1;
	}

	u = ast_module_user_add(chan);

	cfg = ast_config_load(FESTIVAL_CONFIG);
	if (!cfg) {
		ast_log(LOG_WARNING, "No such configuration file %s\n", FESTIVAL_CONFIG);
		ast_module_user_remove(u);
		return -1;
	}
	if (!(host = ast_variable_retrieve(cfg, "general", "host"))) {
		host = "localhost";
	}
	if (!(temp = ast_variable_retrieve(cfg, "general", "port"))) {
		port = 1314;
	} else {
		port = atoi(temp);
	}
	if (!(temp = ast_variable_retrieve(cfg, "general", "usecache"))) {
		usecache=0;
	} else {
		usecache = ast_true(temp);
	}
	if (!(cachedir = ast_variable_retrieve(cfg, "general", "cachedir"))) {
		cachedir = "/tmp/";
	}
	if (!(festivalcommand = ast_variable_retrieve(cfg, "general", "festivalcommand"))) {
		festivalcommand = "(tts_textasterisk \"%s\" 'file)(quit)\n";
	} else { /* This else parses the festivalcommand that we're sent from the config file for \n's, etc */
		int i, j;
		newfestivalcommand = alloca(strlen(festivalcommand) + 1);

		for (i = 0, j = 0; i < strlen(festivalcommand); i++) {
			if (festivalcommand[i] == '\\' && festivalcommand[i + 1] == 'n') {
				newfestivalcommand[j++] = '\n';
				i++;
			} else if (festivalcommand[i] == '\\') {
				newfestivalcommand[j++] = festivalcommand[i + 1];
				i++;
			} else
				newfestivalcommand[j++] = festivalcommand[i];
		}
		newfestivalcommand[j] = '\0';
		festivalcommand = newfestivalcommand;
	}
	
	data = ast_strdupa(vdata);

	intstr = strchr(data, '|');
	if (intstr) {	
		*intstr = '\0';
		intstr++;
		if (!strcasecmp(intstr, "any"))
			intstr = AST_DIGIT_ANY;
	}
	
	ast_log(LOG_DEBUG, "Text passed to festival server : %s\n",(char *)data);
	/* Connect to local festival server */
	
    	fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

    	if (fd < 0) {
		ast_log(LOG_WARNING,"festival_client: can't get socket\n");
		ast_config_destroy(cfg);
		ast_module_user_remove(u);
        	return -1;
	}
        memset(&serv_addr, 0, sizeof(serv_addr));
        if ((serv_addr.sin_addr.s_addr = inet_addr(host)) == -1) {
	        /* its a name rather than an ipnum */
	        serverhost = ast_gethostbyname(host, &ahp);
	        if (serverhost == (struct hostent *)0) {
        	    	ast_log(LOG_WARNING,"festival_client: gethostbyname failed\n");
			ast_config_destroy(cfg);
			ast_module_user_remove(u);
	            	return -1;
        	}
	        memmove(&serv_addr.sin_addr,serverhost->h_addr, serverhost->h_length);
    	}
	serv_addr.sin_family = AF_INET;
	serv_addr.sin_port = htons(port);

	if (connect(fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) != 0) {
		ast_log(LOG_WARNING,"festival_client: connect to server failed\n");
		ast_config_destroy(cfg);
		ast_module_user_remove(u);
        	return -1;
    	}
    	
    	/* Compute MD5 sum of string */
    	MD5Init(&md5ctx);
    	MD5Update(&md5ctx,(unsigned char const *)data,strlen(data));
    	MD5Final(MD5Res,&md5ctx);
		MD5Hex[0] = '\0';
    	
    	/* Convert to HEX and look if there is any matching file in the cache 
    		directory */
    	for (i=0;i<16;i++) {
    		snprintf(koko, sizeof(koko), "%X",MD5Res[i]);
    		strncat(MD5Hex, koko, sizeof(MD5Hex) - strlen(MD5Hex) - 1);
    	}
    	readcache=0;
    	writecache=0;
    	if (strlen(cachedir)+strlen(MD5Hex)+1<=MAXFESTLEN && (usecache==-1)) {
    		snprintf(cachefile, sizeof(cachefile), "%s/%s", cachedir, MD5Hex);
    		fdesc=open(cachefile,O_RDWR);
    		if (fdesc==-1) {
    			fdesc=open(cachefile,O_CREAT|O_RDWR,0777);
    			if (fdesc!=-1) {
    				writecache=1;
    				strln=strlen((char *)data);
    				ast_log(LOG_DEBUG,"line length : %d\n",strln);
    				if (write(fdesc,&strln,sizeof(int)) < 0) {
					ast_log(LOG_WARNING, "write() failed: %s\n", strerror(errno));
				}
    				if (write(fdesc,data,strln) < 0) {
					ast_log(LOG_WARNING, "write() failed: %s\n", strerror(errno));
				}
				seekpos=lseek(fdesc,0,SEEK_CUR);
				ast_log(LOG_DEBUG,"Seek position : %d\n",seekpos);
    			}
    		} else {
    			if (read(fdesc,&strln,sizeof(int)) != sizeof(int)) {
				ast_log(LOG_WARNING, "read() failed: %s\n", strerror(errno));
			}
    			ast_log(LOG_DEBUG,"Cache file exists, strln=%d, strlen=%d\n",strln,(int)strlen((char *)data));
    			if (strlen((char *)data)==strln) {
    				ast_log(LOG_DEBUG,"Size OK\n");
    				if (read(fdesc,&bigstring,strln) != strln) {
					ast_log(LOG_WARNING, "read() failed: %s\n", strerror(errno));
				}
	    			bigstring[strln] = 0;
				if (strcmp(bigstring,data)==0) { 
	    				readcache=1;
	    			} else {
	    				ast_log(LOG_WARNING,"Strings do not match\n");
	    			}
	    		} else {
	    			ast_log(LOG_WARNING,"Size mismatch\n");
	    		}
	    	}
	}
    			
	if (readcache==1) {
		close(fd);
		fd=fdesc;
		ast_log(LOG_DEBUG,"Reading from cache...\n");
	} else {
		ast_log(LOG_DEBUG,"Passing text to festival...\n");
    		fs=fdopen(dup(fd),"wb");
		fprintf(fs,festivalcommand,(char *)data);
		fflush(fs);
		fclose(fs);
	}
	
	/* Write to cache and then pass it down */
	if (writecache==1) {
		ast_log(LOG_DEBUG,"Writing result to cache...\n");
		while ((strln=read(fd,buffer,16384))!=0) {
			if (write(fdesc,buffer,strln) < 0) {
				ast_log(LOG_WARNING, "write() failed: %s\n", strerror(errno));
			}
		}
		close(fd);
		close(fdesc);
		fd=open(cachefile,O_RDWR);
		lseek(fd,seekpos,SEEK_SET);
	}
	
	ast_log(LOG_DEBUG,"Passing data to channel...\n");
	
	/* Read back info from server */
	/* This assumes only one waveform will come back, also LP is unlikely */
	wave = 0;
	do {
               int read_data;
		for (n=0; n < 3; )
               {
                       read_data = read(fd,ack+n,3-n);
                       /* this avoids falling in infinite loop
                        * in case that festival server goes down
                        * */
                       if ( read_data == -1 )
                       {
                               ast_log(LOG_WARNING,"Unable to read from cache/festival fd\n");
			       close(fd);
			       ast_config_destroy(cfg);
			       ast_module_user_remove(u);
                               return -1;
                       }
                       n += read_data;
               }
		ack[3] = '\0';
		if (strcmp(ack,"WV\n") == 0) {         /* receive a waveform */
			ast_log(LOG_DEBUG,"Festival WV command\n");
			waveform = socket_receive_file_to_buff(fd,&filesize);
			res = send_waveform_to_channel(chan,waveform,filesize, intstr);
			free(waveform);
			break;
		}
		else if (strcmp(ack,"LP\n") == 0) {   /* receive an s-expr */
			ast_log(LOG_DEBUG,"Festival LP command\n");
			waveform = socket_receive_file_to_buff(fd,&filesize);
			waveform[filesize]='\0';
			ast_log(LOG_WARNING,"Festival returned LP : %s\n",waveform);
			free(waveform);
		} else if (strcmp(ack,"ER\n") == 0) {    /* server got an error */
			ast_log(LOG_WARNING,"Festival returned ER\n");
			res=-1;
			break;
    		}
	} while (strcmp(ack,"OK\n") != 0);
	close(fd);
	ast_config_destroy(cfg);
	ast_module_user_remove(u);
	return res;

}

static int unload_module(void)
{
	int res;

	res = ast_unregister_application(app);

	ast_module_user_hangup_all();

	return res;
}

static int load_module(void)
{
	struct ast_config *cfg = ast_config_load(FESTIVAL_CONFIG);
	if (!cfg) {
		ast_log(LOG_WARNING, "No such configuration file %s\n", FESTIVAL_CONFIG);
		return AST_MODULE_LOAD_DECLINE;
	}
	ast_config_destroy(cfg);
	return ast_register_application(app, festival_exec, synopsis, descrip);
}

AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Simple Festival Interface");