/*
 * Asterisk -- A telephony toolkit for Linux.
 *
 * Connect to festival
 * 
 * Copyright (C) 2002, Christos Ricudis
 *
 * Christos Ricudis <ricudis@paiko.gr>
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License
 */

#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 <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 <pthread.h>


#define FESTIVAL_CONFIG "festival.conf"

static char *tdesc = "Simple Festival Interface";

static char *app = "Festival";

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

static char *descrip = 
"  Festival():  Connect to Festival, send the argument, get back the waveform,"
"play it to the user.\n";

STANDARD_LOCAL_USER;

LOCAL_USER_DECL;

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;
    buff = (char *)malloc(bufflen);
    *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;
            buff = (char *)realloc(buff,bufflen);
        }
        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;
        res = fork();
        if (res < 0)
                ast_log(LOG_WARNING, "Fork failed\n");
        if (res)
                return res;
        for (x=0;x<256;x++) {
                if (x != fd)
                        close(x);
        }
	write(fd,waveform,length);
	write(fd,"a",1);
	close(fd);
	exit(0);
}


static int send_waveform_to_channel(struct ast_channel *chan, char *waveform, int length) {
	int res=0;
	int fds[2];
	int rfds[1 + AST_MAX_FDS];
	int ms = -1;
	int pid = -1;
	int us;
	int exception;
	int owriteformat;
	struct timeval tv;
	struct timeval last;
	struct ast_frame *f;
	int x;
	struct myframe {
		struct ast_frame f;
		char offset[AST_FRIENDLY_OFFSET];
		char frdata[160];
	} myf;
	last.tv_usec = 0;
	last.tv_sec = 0;
	
        if (pipe(fds)) {
                 ast_log(LOG_WARNING, "Unable to create pipe\n");
        	return -1;
        }
	                                                
	ast_stopstream(chan);

	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 */
		rfds[AST_MAX_FDS] = fds[0];
		for (;;) {
			CHECK_BLOCKING(chan);
			for (x=0;x<AST_MAX_FDS;x++) 
				rfds[x] = chan->fds[x];
  			res = ast_waitfor_n_fd(rfds, AST_MAX_FDS+1, &ms, &exception);
			chan->blocking = 0;
			if (res < 1) {
				ast_log(LOG_DEBUG, "Hangup detected\n");
				res = -1;
				break;
			}
			for(x=0;x<AST_MAX_FDS;x++) 
				if (res == chan->fds[x])
					break;

			if (x < AST_MAX_FDS) {
				if (exception)
					chan->exception = 1;
				f = ast_read(chan);
				if (!f) {
					ast_log(LOG_DEBUG, "Null frame == hangup() detected\n");
					res = -1;
					break;
				}
				if (f->frametype == AST_FRAME_DTMF) {
					ast_log(LOG_DEBUG, "User pressed a key\n");
					ast_frfree(f);
					res = 0;
					break;
				}
				ast_frfree(f);
			} else if (res == fds[0]) {
				gettimeofday(&tv, NULL);
				if (last.tv_sec || last.tv_usec) {
					/* We should wait at least a frame length */
					us = sizeof(myf.frdata) / 16 * 1000;
					/* Subtract 1,000,000 us for each second late we've passed */
					us -= (tv.tv_sec - last.tv_sec) * 1000000;
					/* And one for each us late we've passed */
					us -= (tv.tv_usec - last.tv_usec);
					/* Sleep that long if needed */
					if (us > 0)
						usleep(us);
				}
				last = tv;
				res = read(fds[0], myf.frdata, sizeof(myf.frdata));
				if (res > 0) {
					myf.f.frametype = AST_FRAME_VOICE;
					myf.f.subclass = AST_FORMAT_SLINEAR;
					myf.f.datalen = res;
					myf.f.timelen = res / 16;
					myf.f.mallocd = 0;
					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;
						break;
					}
					if (res < sizeof(myf.frdata)) { // last frame
						ast_log(LOG_WARNING, "Last frame\n");
						res=0;
						break;
					}
				} else {
					ast_log(LOG_WARNING, "No more waveform\n");
					res = 0;
				}
			} else {
				ast_log(LOG_DEBUG, "HuhHHH?\n");
				res = -1;
				break;
			}
		}
	}
	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 *data)
{
	int usecache;
	int res=0;
	struct localuser *u;
 	struct sockaddr_in serv_addr;
	struct hostent *serverhost;
	int fd;
	FILE *fs;
	char *host;
	char *cachedir;
	char *temp;
	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[32];
	char koko[4];
	char cachefile[MAXFESTLEN];
	int readcache=0;
	int writecache=0;
	int strln;
	int fdesc;
	char buffer[16384];
	int seekpos;	
	
	struct ast_config *cfg;
	cfg = ast_load(FESTIVAL_CONFIG);
	if (!cfg) {
		ast_log(LOG_WARNING, "No such configuration file %s\n", FESTIVAL_CONFIG);
		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 {
		if (strcasecmp(temp,"yes")==0) {
			usecache=1;
		}
	}
	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";
	}
	
		

	if (!data) {
		ast_log(LOG_WARNING, "festival requires an argument (text)\n");
		return -1;
	}
	LOCAL_USER_ADD(u);
	ast_log(LOG_WARNING, "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");
        	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 = gethostbyname(host);
	        if (serverhost == (struct hostent *)0) {
        	    	ast_log(LOG_WARNING,"festival_client: gethostbyname failed\n");
	            	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");
        	return -1;
    	}
    	
    	/* Compute MD5 sum of string */
    	MD5Init(&md5ctx);
    	MD5Update(&md5ctx,(unsigned char const *)data,strlen(data));
    	MD5Final(MD5Res,&md5ctx);
    	strcpy(MD5Hex,"");
    	
    	/* Convert to HEX and look if there is any matching file in the cache 
    		directory */
    	for (i=0;i<16;i++) {
    		sprintf(koko,"%X",MD5Res[i]);
    		strcat(MD5Hex,koko);
    	}
    	readcache=0;
    	writecache=0;
    	if (strlen(cachedir)+strlen(MD5Hex)+1<=MAXFESTLEN && (usecache==1)) {
    		sprintf(cachefile,"%s/%s",cachedir,MD5Hex);
    		fdesc=open(cachefile,O_RDWR);
    		if (fdesc==-1) {
    			fdesc=open(cachefile,O_CREAT|O_RDWR,0);
    			if (fdesc!=-1) {
    				writecache=1;
    				strln=strlen((char *)data);
    				ast_log(LOG_WARNING,"line length : %d\n",strln);
    				write(fdesc,&strln,sizeof(int));
    				write(fdesc,data,strln);
				seekpos=lseek(fdesc,0,SEEK_CUR);
				ast_log(LOG_WARNING,"Seek position : %d\n",seekpos);
    			}
    		} else {
    			read(fdesc,&strln,sizeof(int));
    			ast_log(LOG_WARNING,"Cache file exists, strln=%d, strlen=%d\n",strln,strlen((char *)data));
    			if (strlen((char *)data)==strln) {
    				ast_log(LOG_WARNING,"Size OK\n");
    				read(fdesc,&bigstring,strln);
	    			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_WARNING,"Reading from cache...\n");
	} else {
		ast_log(LOG_WARNING,"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_WARNING,"Writing result to cache...\n");
		while ((strln=read(fd,buffer,16384))!=0) {
			write(fdesc,buffer,strln);
		}
		close(fd);
		close(fdesc);
		fd=open(cachefile,O_RDWR);
		lseek(fd,seekpos,SEEK_SET);
	}
	
	ast_log(LOG_WARNING,"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 {
		for (n=0; n < 3; )
			n += read(fd,ack+n,3-n);
		ack[3] = '\0';
		if (strcmp(ack,"WV\n") == 0) {         /* receive a waveform */
			ast_log(LOG_WARNING,"Festival WV command");
			waveform = socket_receive_file_to_buff(fd,&filesize);
			send_waveform_to_channel(chan,waveform,filesize);
			free(waveform);
			res=0;
			break;
		}
		else if (strcmp(ack,"LP\n") == 0) {   /* receive an s-expr */
			ast_log(LOG_WARNING,"Festival LP command");
			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);
	LOCAL_USER_REMOVE(u);                                                                                
	return res;

}

int unload_module(void)
{
	STANDARD_HANGUP_LOCALUSERS;
	return ast_unregister_application(app);
}

int load_module(void)
{
	
	return ast_register_application(app, festival_exec, synopsis, descrip);
}

char *description(void)
{
	return tdesc;
}

int usecount(void)
{
	int res;
	STANDARD_USECOUNT(res);
	return res;
}

char *key()
{
	return ASTERISK_GPL_KEY;
}