/*
 * Asterisk -- A telephony toolkit for Linux.
 *
 * Frame manipulation routines
 * 
 * Copyright (C) 1999, Mark Spencer
 *
 * Mark Spencer <markster@linux-support.net>
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License
 */

#include <asterisk/lock.h>
#include <asterisk/frame.h>
#include <asterisk/logger.h>
#include <asterisk/options.h>
#include <asterisk/cli.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <pthread.h>
#include "asterisk.h"

#ifdef TRACE_FRAMES
static int headers = 0;
static struct ast_frame *headerlist = NULL;
static pthread_mutex_t framelock = AST_MUTEX_INITIALIZER;
#endif

#define SMOOTHER_SIZE 8000

struct ast_smoother {
	int size;
	int format;
	int readdata;
	int optimizablestream;
	float samplesperbyte;
	struct ast_frame f;
	char data[SMOOTHER_SIZE];
	char framedata[SMOOTHER_SIZE + AST_FRIENDLY_OFFSET];
	struct ast_frame *opt;
	int len;
};

void ast_smoother_reset(struct ast_smoother *s, int size)
{
	memset(s, 0, sizeof(struct ast_smoother));
	s->size = size;
}

struct ast_smoother *ast_smoother_new(int size)
{
	struct ast_smoother *s;
	if (size < 1)
		return NULL;
	s = malloc(sizeof(struct ast_smoother));
	if (s)
		ast_smoother_reset(s, size);
	return s;
}

int ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f)
{
	if (f->frametype != AST_FRAME_VOICE) {
		ast_log(LOG_WARNING, "Huh?  Can't smooth a non-voice frame!\n");
		return -1;
	}
	if (!s->format) {
		s->format = f->subclass;
		s->samplesperbyte = (float)f->samples / (float)f->datalen;
	} else if (s->format != f->subclass) {
		ast_log(LOG_WARNING, "Smoother was working on %d format frames, now trying to feed %d?\n", s->format, f->subclass);
		return -1;
	}
	if (s->len + f->datalen > SMOOTHER_SIZE) {
		ast_log(LOG_WARNING, "Out of smoother space\n");
		return -1;
	}
	if ((f->datalen == s->size) && !s->opt) {
		if (!s->len) {
			/* Optimize by sending the frame we just got
			   on the next read, thus eliminating the douple
			   copy */
			s->opt = f;
			return 0;
		} else {
			s->optimizablestream++;
			if (s->optimizablestream > 10) {
				/* For the past 10 rounds, we have input and output
				   frames of the correct size for this smoother, yet
				   we were unable to optimize because there was still
				   some cruft left over.  Lets just drop the cruft so
				   we can move to a fully optimized path */
				s->len = 0;
				s->opt = f;
				return 0;
			}
		}
	} else 
		s->optimizablestream = 0;
	memcpy(s->data + s->len, f->data, f->datalen);
	s->len += f->datalen;
	return 0;
}

struct ast_frame *ast_smoother_read(struct ast_smoother *s)
{
	struct ast_frame *opt;

	/* IF we have an optimization frame, send it */
	if (s->opt) {
		opt = s->opt;
		s->opt = NULL;
		return opt;
	}

	/* Make sure we have enough data */
	if (s->len < s->size) {
		return NULL;
	}
	/* Make frame */
	s->f.frametype = AST_FRAME_VOICE;
	s->f.subclass = s->format;
	s->f.data = s->framedata + AST_FRIENDLY_OFFSET;
	s->f.offset = AST_FRIENDLY_OFFSET;
	s->f.datalen = s->size;
	s->f.samples = s->size * s->samplesperbyte;
	/* Fill Data */
	memcpy(s->f.data, s->data, s->size);
	s->len -= s->size;
	/* Move remaining data to the front if applicable */
	if (s->len) 
		memmove(s->data, s->data + s->size, s->len);
	/* Return frame */
	return &s->f;
}

void ast_smoother_free(struct ast_smoother *s)
{
	free(s);
}

static struct ast_frame *ast_frame_header_new(void)
{
	struct ast_frame *f;
	f = malloc(sizeof(struct ast_frame));
	if (f)
		memset(f, 0, sizeof(struct ast_frame));
#ifdef TRACE_FRAMES
	if (f) {
		headers++;
		f->prev = NULL;
		ast_pthread_mutex_lock(&framelock);
		f->next = headerlist;
		if (headerlist)
			headerlist->prev = f;
		headerlist = f;
		pthread_mutex_unlock(&framelock);
	}
#endif	
	return f;
}

/*
 * Important: I should be made more efficient.  Frame headers should
 * most definitely be cached
 */

void ast_frfree(struct ast_frame *fr)
{
	if (fr->mallocd & AST_MALLOCD_DATA) {
		if (fr->data) 
			free(fr->data - fr->offset);
	}
	if (fr->mallocd & AST_MALLOCD_SRC) {
		if (fr->src)
			free(fr->src);
	}
	if (fr->mallocd & AST_MALLOCD_HDR) {
#ifdef TRACE_FRAMES
		headers--;
		ast_pthread_mutex_lock(&framelock);
		if (fr->next)
			fr->next->prev = fr->prev;
		if (fr->prev)
			fr->prev->next = fr->next;
		else
			headerlist = fr->next;
		pthread_mutex_unlock(&framelock);
#endif			
		free(fr);
	}
}

struct ast_frame *ast_frisolate(struct ast_frame *fr)
{
	struct ast_frame *out;
	if (!(fr->mallocd & AST_MALLOCD_HDR)) {
		/* Allocate a new header if needed */
		out = ast_frame_header_new();
		if (!out) {
			ast_log(LOG_WARNING, "Out of memory\n");
			return NULL;
		}
		out->frametype = fr->frametype;
		out->subclass = fr->subclass;
		out->datalen = 0;
		out->samples = fr->samples;
		out->offset = 0;
		out->src = NULL;
		out->data = NULL;
	} else {
		out = fr;
	}
	if (!(fr->mallocd & AST_MALLOCD_SRC)) {
		if (fr->src)
			out->src = strdup(fr->src);
	} else
		out->src = fr->src;
	if (!(fr->mallocd & AST_MALLOCD_DATA))  {
		out->data = malloc(fr->datalen + AST_FRIENDLY_OFFSET);
		if (!out->data) {
			free(out);
			ast_log(LOG_WARNING, "Out of memory\n");
			return NULL;
		}
		out->data += AST_FRIENDLY_OFFSET;
		out->offset = AST_FRIENDLY_OFFSET;
		out->datalen = fr->datalen;
		memcpy(out->data, fr->data, fr->datalen);
	}
	out->mallocd = AST_MALLOCD_HDR | AST_MALLOCD_SRC | AST_MALLOCD_DATA;
	return out;
}

struct ast_frame *ast_frdup(struct ast_frame *f)
{
	struct ast_frame *ret;
	int p;
	p = f->mallocd;
	f->mallocd = 0;
	/* Make frisolate think this is a 100% static frame, and make a duplicate */
	ret = ast_frisolate(f);
	/* Restore its true malloc status */
	f->mallocd = p;
	return ret;
}

struct ast_frame *ast_fr_fdread(int fd)
{
	char buf[65536];
	int res;
	int ttl = sizeof(struct ast_frame);
	struct ast_frame *f = (struct ast_frame *)buf;
	/* Read a frame directly from there.  They're always in the
	   right format. */
	
	while(ttl) {
		res = read(fd, buf, ttl);
		if (res < 0) {
			ast_log(LOG_WARNING, "Bad read on %d: %s\n", fd, strerror(errno));
			return NULL;
		}
		ttl -= res;
	}
	
	/* read the frame header */
	f->mallocd = 0;
	/* Re-write data position */
	f->data = buf + sizeof(struct ast_frame);
	f->offset = 0;
	/* Forget about being mallocd */
	f->mallocd = 0;
	/* Re-write the source */
	f->src = __FUNCTION__;
	if (f->datalen > sizeof(buf) - sizeof(struct ast_frame)) {
		/* Really bad read */
		ast_log(LOG_WARNING, "Strange read (%d bytes)\n", f->datalen);
		return NULL;
	}
	if (f->datalen) {
		if ((res = read(fd, f->data, f->datalen)) != f->datalen) {
			/* Bad read */
			ast_log(LOG_WARNING, "How very strange, expected %d, got %d\n", f->datalen, res);
			return NULL;
		}
	}
	if ((f->frametype == AST_FRAME_CONTROL) && (f->subclass == AST_CONTROL_HANGUP)) {
		return NULL;
	}
	return ast_frisolate(f);
}

/* Some convenient routines for sending frames to/from stream or datagram
   sockets, pipes, etc (maybe even files) */

int ast_fr_fdwrite(int fd, struct ast_frame *frame)
{
	/* Write the frame exactly */
	if (write(fd, frame, sizeof(struct ast_frame)) != sizeof(struct ast_frame)) {
		ast_log(LOG_WARNING, "Write error: %s\n", strerror(errno));
		return -1;
	}
	if (write(fd, frame->data, frame->datalen) != frame->datalen) {
		ast_log(LOG_WARNING, "Write error: %s\n", strerror(errno));
		return -1;
	}
	return 0;
}

int ast_fr_fdhangup(int fd)
{
	struct ast_frame hangup = {
		AST_FRAME_CONTROL,
		AST_CONTROL_HANGUP
	};
	return ast_fr_fdwrite(fd, &hangup);
}

int ast_getformatbyname(char *name)
{
	if (!strcasecmp(name, "g723.1")) 
		return AST_FORMAT_G723_1;
	else if (!strcasecmp(name, "gsm"))
		return AST_FORMAT_GSM;
	else if (!strcasecmp(name, "ulaw"))
		return AST_FORMAT_ULAW;
	else if (!strcasecmp(name, "alaw"))
		return AST_FORMAT_ALAW;
	else if (!strcasecmp(name, "mp3"))
		return AST_FORMAT_MP3;
	else if (!strcasecmp(name, "slinear"))
		return AST_FORMAT_SLINEAR;
	else if (!strcasecmp(name, "lpc10"))
		return AST_FORMAT_LPC10;
	else if (!strcasecmp(name, "adpcm"))
		return AST_FORMAT_ADPCM;
	else if (!strcasecmp(name, "g729"))
		return AST_FORMAT_G729A;
	else if (!strcasecmp(name, "speex"))
		return AST_FORMAT_SPEEX;
	else if (!strcasecmp(name, "all"))
		return 0x7FFFFFFF;
	return 0;
}

#ifdef TRACE_FRAMES
static int show_frame_stats(int fd, int argc, char *argv[])
{
	struct ast_frame *f;
	int x=1;
	if (argc != 3)
		return RESULT_SHOWUSAGE;
	ast_cli(fd, "     Framer Statistics     \n");
	ast_cli(fd, "---------------------------\n");
	ast_cli(fd, "Total allocated headers: %d\n", headers);
	ast_cli(fd, "Queue Dump:\n");
	ast_pthread_mutex_lock(&framelock);
	for (f=headerlist; f; f = f->next) {
		ast_cli(fd, "%d.  Type %d, subclass %d from %s\n", x++, f->frametype, f->subclass, f->src ? f->src : "<Unknown>");
	}
	pthread_mutex_unlock(&framelock);
	return RESULT_SUCCESS;
}

static char frame_stats_usage[] =
"Usage: show frame stats\n"
"       Displays debugging statistics from framer\n";

struct ast_cli_entry cli_frame_stats =
{ { "show", "frame", "stats", NULL }, show_frame_stats, "Shows frame statistics", frame_stats_usage };
#endif

int init_framer(void)
{
#ifdef TRACE_FRAMES
	ast_cli_register(&cli_frame_stats);
#endif
	return 0;	
}