/*
 * Asterisk -- A telephony toolkit for Linux.
 *
 * Generic File Format Support.
 * 
 * Copyright (C) 1999, Adtran Inc. and Linux Support Services, LLC
 *
 * Mark Spencer <markster@linux-support.net>
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License
 */

#include <asterisk/frame.h>
#include <asterisk/file.h>
#include <asterisk/logger.h>
#include <asterisk/channel.h>
#include <asterisk/sched.h>
#include <asterisk/options.h>
#include <asterisk/translate.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <stdio.h>
#include <fcntl.h>
#include <dirent.h>
#include <sys/stat.h>
#include "asterisk.h"

struct ast_format {
	/* Name of format */
	char name[80];
	/* Extensions (separated by | if more than one) 
	   this format can read.  First is assumed for writing (e.g. .mp3) */
	char exts[80];
	/* Format of frames it uses/provides (one only) */
	int format;
	/* Open an input stream, and start playback */
	struct ast_filestream * (*open)(int fd);
	/* Open an output stream, of a given file descriptor and comment it appropriately if applicable */
	struct ast_filestream * (*rewrite)(int fd, char *comment);
	/* Apply a reading filestream to a channel */
	int (*apply)(struct ast_channel *, struct ast_filestream *);
	/* Write a frame to a channel */
	int (*write)(struct ast_filestream *, struct ast_frame *);
	/* Read the next frame from the filestream (if available) */
	struct ast_frame * (*read)(struct ast_filestream *);
	/* Close file, and destroy filestream structure */
	void (*close)(struct ast_filestream *);
	/* Retrieve file comment */
	char * (*getcomment)(struct ast_filestream *);
	/* Link */
	struct ast_format *next;
};

struct ast_filestream {
	/* Everybody reserves a block of AST_RESERVED_POINTERS pointers for us */
	struct ast_format *fmt;
	/* Transparently translate from another format -- just once */
	struct ast_trans_pvt *trans;
	struct ast_tranlator_pvt *tr;
};

static pthread_mutex_t formatlock = PTHREAD_MUTEX_INITIALIZER;

static struct ast_format *formats = NULL;

int ast_format_register(char *name, char *exts, int format,
						struct ast_filestream * (*open)(int fd),
						struct ast_filestream * (*rewrite)(int fd, char *comment),
						int (*apply)(struct ast_channel *, struct ast_filestream *),
						int (*write)(struct ast_filestream *, struct ast_frame *),
						struct ast_frame * (*read)(struct ast_filestream *),
						void (*close)(struct ast_filestream *),
						char * (*getcomment)(struct ast_filestream *))
{
	struct ast_format *tmp;
	if (pthread_mutex_lock(&formatlock)) {
		ast_log(LOG_WARNING, "Unable to lock format list\n");
		return -1;
	}
	tmp = formats;
	while(tmp) {
		if (!strcasecmp(name, tmp->name)) {
			pthread_mutex_unlock(&formatlock);
			ast_log(LOG_WARNING, "Tried to register '%s' format, already registered\n", name);
			return -1;
		}
		tmp = tmp->next;
	}
	tmp = malloc(sizeof(struct ast_format));
	if (!tmp) {
		ast_log(LOG_WARNING, "Out of memory\n");
		pthread_mutex_unlock(&formatlock);
		return -1;
	}
	strncpy(tmp->name, name, sizeof(tmp->name));
	strncpy(tmp->exts, exts, sizeof(tmp->exts));
	tmp->open = open;
	tmp->rewrite = rewrite;
	tmp->apply = apply;
	tmp->read = read;
	tmp->write = write;
	tmp->close = close;
	tmp->format = format;
	tmp->getcomment = getcomment;
	tmp->next = formats;
	formats = tmp;
	pthread_mutex_unlock(&formatlock);
	if (option_verbose > 1)
		ast_verbose( VERBOSE_PREFIX_2 "Registered file format %s, extension(s) %s\n", name, exts);
	return 0;
}

int ast_format_unregister(char *name)
{
	struct ast_format *tmp, *tmpl = NULL;
	if (pthread_mutex_lock(&formatlock)) {
		ast_log(LOG_WARNING, "Unable to lock format list\n");
		return -1;
	}
	tmp = formats;
	while(tmp) {
		if (!strcasecmp(name, tmp->name)) {
			if (tmpl) 
				tmpl->next = tmp->next;
			else
				formats = tmp->next;
			free(tmp);
			pthread_mutex_unlock(&formatlock);
			if (option_verbose > 1)
				ast_verbose( VERBOSE_PREFIX_2 "Unregistered format %s\n", name);
			return 0;
		}
		tmp = tmp->next;
	}
	ast_log(LOG_WARNING, "Tried to unregister format %s, already unregistered\n", name);
	return -1;
}

int ast_stopstream(struct ast_channel *tmp)
{
	if (tmp->trans)
		tmp = tmp->trans;
	/* Stop a running stream if there is one */
	if (!tmp->stream) 
		return 0;
	tmp->stream->fmt->close(tmp->stream);
	if (tmp->master) {
		ast_translator_destroy(tmp);
	}
	return 0;
}

int ast_closestream(struct ast_filestream *f)
{
	if (f->trans) {
		ast_translator_free_path(f->trans);
	}
	/* Stop a running stream if there is one */
	f->fmt->close(f);
	return 0;
}

int ast_writestream(struct ast_filestream *fs, struct ast_frame *f)
{
	struct ast_frame_chain *fc, *f2;
	int res = -1;
	int count=0;
	if (f->frametype != AST_FRAME_VOICE) {
		ast_log(LOG_WARNING, "Tried to write non-voice frame\n");
		return -1;
	}
	if ((fs->fmt->format & f->subclass) == f->subclass)
		return fs->fmt->write(fs, f);
	else {
		/* XXX If they try to send us a type of frame that isn't the normal frame, and isn't
		       the one we've setup a translator for, we do the "wrong thing" XXX */
		if (!fs->trans) 
			fs->trans = ast_translator_build_path(f->subclass, fs->fmt->format);
		if (!fs->trans)
			ast_log(LOG_WARNING, "Unable to translate to format %s, source format %d\n", fs->fmt->name, f->subclass);
		else {
			/* Build a chain of translated frames */
			fc = ast_translate(fs->trans, f);
			f2 = fc;
			while(f2) {
				res = fs->fmt->write(fs, f2->fr);
				if (res) {
					ast_log(LOG_WARNING, "Frame write failed\n");
					break;
				}
				f2 = f2->next;
				count++;
				if (count > 1) 
					ast_log(LOG_DEBUG, "Count is %d\n", count);
			}
			if (fc)
				ast_frchain(fc);
		}
		return res;
	}
}

static char *build_filename(char *filename, char *ext)
{
	char *fn;
	fn = malloc(strlen(AST_SOUNDS) + strlen(filename) + strlen(ext) + 10);
	if (fn) {
		if (filename[0] == '/') 
			sprintf(fn, "%s.%s", filename, ext);
		else
			sprintf(fn, "%s/%s.%s", AST_SOUNDS, filename, ext);
	}
	return fn;
	
}

#define ACTION_EXISTS 1
#define ACTION_DELETE 2
#define ACTION_RENAME 3
#define ACTION_OPEN   4

static int ast_filehelper(char *filename, char *filename2, char *fmt, int action)
{
	struct stat st;
	struct ast_format *f;
	struct ast_filestream *s;
	int res=0, ret = 0;
	char *ext=NULL, *exts, *fn, *nfn;
	struct ast_channel *trans = (struct ast_channel *)filename2;
	
	/* Start with negative response */
	if (action == ACTION_EXISTS)
		res = 0;
	else
		res = -1;
	if (action == ACTION_OPEN)
		ret = -1;
	/* Check for a specific format */
	if (pthread_mutex_lock(&formatlock)) {
		ast_log(LOG_WARNING, "Unable to lock format list\n");
		if (action == ACTION_EXISTS)
			return 0;
		else
			return -1;
	}
	f = formats;
	while(f) {
		if (!fmt || !strcasecmp(f->name, fmt)) {
			exts = strdup(f->exts);
			/* Try each kind of extension */
			ext = strtok(exts, "|");
			do {
				fn = build_filename(filename, ext);
				if (fn) {
					res = stat(fn, &st);
					if (!res) {
						switch(action) {
						case ACTION_EXISTS:
							ret |= f->format;
							break;
						case ACTION_DELETE:
							res = unlink(fn);
							if (res)
								ast_log(LOG_WARNING, "unlink(%s) failed: %s\n", fn, strerror(errno));
							break;
						case ACTION_RENAME:
							nfn = build_filename(filename2, ext);
							if (nfn) {
								res = rename(fn, nfn);
								if (res)
									ast_log(LOG_WARNING, "rename(%s,%s) failed: %s\n", fn, nfn, strerror(errno));
								free(nfn);
							} else
								ast_log(LOG_WARNING, "Out of memory\n");
							break;
						case ACTION_OPEN:
							if ((ret < 0) && ((trans->format & f->format) /* == trans->format */)) {
								ret = open(fn, O_RDONLY);
								if (ret >= 0) {
									s = f->open(ret);
									if (s) {
										s->fmt = f;
										s->trans = NULL;
										trans->stream = s;
										if (f->apply(trans, s)) {
											f->close(s);
											trans->stream = NULL;
											ast_log(LOG_WARNING, "Unable to apply stream to channel %s\n", trans->name);
											close(ret);
											ret = 0;
										}
									} else {
										close(ret);
										ast_log(LOG_WARNING, "Unable to open fd on %s\n", filename);
									}
								} else
									ast_log(LOG_WARNING, "Couldn't open file %s\n", fn);
							}
							break;
						default:
							ast_log(LOG_WARNING, "Unknown helper %d\n", action);
						}
						/* Conveniently this logic is the same for all */
						if (res)
							break;
					}
					free(fn);
				}
				ext = strtok(NULL, "|");
			} while(ext);
			free(exts);
		}
		f = f->next;
	}
	pthread_mutex_unlock(&formatlock);
	if ((action == ACTION_EXISTS) || (action == ACTION_OPEN))
		res = ret ? ret : -1;
	return res;
}

int ast_fileexists(char *filename, char *fmt)
{
	return ast_filehelper(filename, NULL, fmt, ACTION_EXISTS);
}

int ast_filedelete(char *filename, char *fmt)
{
	return ast_filehelper(filename, NULL, fmt, ACTION_DELETE);
}

int ast_filerename(char *filename, char *filename2, char *fmt)
{
	return ast_filehelper(filename, filename2, fmt, ACTION_RENAME);
}

int ast_streamfile(struct ast_channel *chan, char *filename)
{
	/* This is a fairly complex routine.  Essentially we should do 
	   the following:
	   
	   1) Find which file handlers produce our type of format.
	   2) Look for a filename which it can handle.
	   3) If we find one, then great.  
	   *4) If not, see what files are there
	   *5) See what we can actually support
	   *6) Choose the one with the least costly translator path and
	       set it up.
		   
		XXX * = unimplemented XXX
	*/
	int fd = -1;
	struct ast_channel *trans;
	int fmts;
	ast_stopstream(chan);
	fmts = ast_fileexists(filename, NULL);
	if (fmts < 1) {
		ast_log(LOG_WARNING, "File %s does not exist in any format\n", filename);
		return -1;
	}
	if (fmts & chan->format) {
		/* No translation necessary -- we have a file in a format our channel can 
		   handle */
		trans = chan;
	} else {
		/* Find the best */
		fmts = ast_translator_best_choice(chan->format, fmts);
		if (fmts < 1) {
			ast_log(LOG_WARNING, "Unable to find a translator method\n");
			return -1;
		}
		trans = ast_translator_create(chan, fmts, AST_DIRECTION_OUT);
		if (!trans) {
			ast_log(LOG_WARNING, "Unable to create translator\n");
			return -1;
		}
	}
 	fd = ast_filehelper(filename, (char *)trans, NULL, ACTION_OPEN);
	if (fd >= 0) {
#if 0
		ast_verbose(VERBOSE_PREFIX_3 "Playing '%s'\n", filename);
#endif
		return 0;
	}
	ast_log(LOG_WARNING, "Unable to open %s (format %d): %s\n", filename, chan->format, strerror(errno));
	if (chan != trans)
		ast_translator_destroy(trans);	
	return -1;
}


struct ast_filestream *ast_writefile(char *filename, char *type, char *comment, int flags, int check, mode_t mode)
{
	int fd;
	struct ast_format *f;
	struct ast_filestream *fs=NULL;
	char *fn;
	char *ext;
	if (pthread_mutex_lock(&formatlock)) {
		ast_log(LOG_WARNING, "Unable to lock format list\n");
		return NULL;
	}
	f = formats;
	while(f) {
		if (!strcasecmp(f->name, type)) {
			/* XXX Implement check XXX */
			ext = strdup(f->exts);
			ext = strtok(ext, "|");
			fn = build_filename(filename, ext);
			fd = open(fn, flags | O_WRONLY | O_CREAT, mode);
			if (fd >= 0) {
				errno = 0;
				if ((fs = f->rewrite(fd, comment))) {
					fs->trans = NULL;
					fs->fmt = f;
				} else {
					ast_log(LOG_WARNING, "Unable to rewrite %s\n", fn);
					close(fd);
					unlink(fn);
				}
			} else if (errno != EEXIST)
				ast_log(LOG_WARNING, "Unable to open file %s: %s\n", fn, strerror(errno));
			free(fn);
			free(ext);
			break;
		}
		f = f->next;
	}
	pthread_mutex_unlock(&formatlock);
	if (!f) 
		ast_log(LOG_WARNING, "No such format '%s'\n", type);
	return fs;
}

char ast_waitstream(struct ast_channel *c, char *breakon)
{
	int res;
	struct ast_frame *fr;
	if (c->trans)
		c=c->trans;
	while(c->stream) {
		res = ast_sched_wait(c->sched);
		if (res < 0) {
			/* Okay, stop :) */
			return 0;
		}
		res = ast_waitfor(c, res);
		if (res < 0) {
			ast_log(LOG_WARNING, "Select failed (%s)\n", strerror(errno));
			return res;
		} else
		if (res > 0) {
			fr = ast_read(c);
			if (!fr) {
#if 0
				ast_log(LOG_DEBUG, "Got hung up\n");
#endif
				return -1;
			}
			
			switch(fr->frametype) {
			case AST_FRAME_DTMF:
				res = fr->subclass;
				ast_frfree(fr);
				if (strchr(breakon, res))
					return res;
				break;
			case AST_FRAME_CONTROL:
				switch(fr->subclass) {
				case AST_CONTROL_HANGUP:
					ast_frfree(fr);
					return -1;
				default:
					ast_log(LOG_WARNING, "Unexpected control subclass '%d'\n", fr->subclass);
				}
			default:
				/* Ignore */
				ast_frfree(fr);
			}
		} else
			ast_sched_runq(c->sched);
	
		
	}
	return 0;
}