/* the Music Player Daemon (MPD)
 * (c)2003-2006 by Warren Dukes (warren.dukes@gmail.com)
 * This project's homepage is: http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include "volume.h"

#include "command.h"
#include "conf.h"
#include "log.h"
#include "player.h"

#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <errno.h>
#ifdef HAVE_OSS
#include <sys/soundcard.h>
#endif
#ifdef HAVE_ALSA
#include <alsa/asoundlib.h>
#endif

#define VOLUME_MIXER_TYPE_SOFTWARE		0
#define VOLUME_MIXER_TYPE_OSS			1
#define VOLUME_MIXER_TYPE_ALSA			2

#define VOLUME_MIXER_SOFTWARE_DEFAULT		""
#define VOLUME_MIXER_OSS_DEFAULT		"/dev/mixer"
#define VOLUME_MIXER_ALSA_DEFAULT		"default"
#define VOLUME_MIXER_ALSA_CONTROL_DEFAULT	"PCM"

#ifdef HAVE_OSS
#define VOLUME_MIXER_TYPE_DEFAULT               VOLUME_MIXER_TYPE_OSS
#define VOLUME_MIXER_DEVICE_DEFAULT             VOLUME_MIXER_OSS_DEFAULT
#else
#ifdef HAVE_ALSA
#define VOLUME_MIXER_TYPE_DEFAULT               VOLUME_MIXER_TYPE_ALSA
#define VOLUME_MIXER_DEVICE_DEFAULT             VOLUME_MIXER_ALSA_DEFAULT
#else
#define VOLUME_MIXER_TYPE_DEFAULT               VOLUME_MIXER_TYPE_SOFTWARE
#define VOLUME_MIXER_DEVICE_DEFAULT             VOLUME_MIXER_SOFTWARE_DEFAULT
#endif
#endif

static int volume_mixerType = VOLUME_MIXER_TYPE_DEFAULT;
static char * volume_mixerDevice = VOLUME_MIXER_DEVICE_DEFAULT;

static int volume_softwareSet = 100;

#ifdef HAVE_OSS
static int volume_ossFd = -1;
static int volume_ossControl = SOUND_MIXER_PCM;
#endif

#ifdef HAVE_ALSA
static snd_mixer_t * volume_alsaMixerHandle = NULL;
static snd_mixer_elem_t * volume_alsaElem;
static long volume_alsaMin;
static long volume_alsaMax;
static int volume_alsaSet = -1;
#endif

#ifdef HAVE_OSS

static void closeOssMixer(void)
{
	while (close(volume_ossFd) && errno == EINTR);
	volume_ossFd = -1;
}

static int prepOssMixer(char * device) {
	ConfigParam * param;

	if((volume_ossFd = open(device,O_RDONLY))<0) {
		WARNING("unable to open oss mixer \"%s\"\n",device);
		return -1;
	}

        param = getConfigParam(CONF_MIXER_CONTROL);

	if(param) {
		char * labels[SOUND_MIXER_NRDEVICES] = SOUND_DEVICE_LABELS;
		char * dup;
		int i,j;
		int devmask = 0;

		if(ioctl(volume_ossFd,SOUND_MIXER_READ_DEVMASK,&devmask)<0) {
			WARNING("errors getting read_devmask for oss mixer\n");
			closeOssMixer();
			return -1;
		}

		for(i=0;i<SOUND_MIXER_NRDEVICES;i++) {
			dup = strdup(labels[i]);
			/* eliminate spaces at the end */
			j = strlen(dup)-1;
			while(j>=0 && dup[j]==' ') dup[j--] = '\0';
			if(strcasecmp(dup, param->value)==0) {
				free(dup);
				break;
			}
			free(dup);
		}

		if(i>=SOUND_MIXER_NRDEVICES) {
			WARNING("mixer control \"%s\" not found at line %i\n",
					        param->value, param->line);
			closeOssMixer();
			return -1;
		}
		else if(!( ( 1 << i ) & devmask )) {
			WARNING("mixer control \"%s\" not usable at line %i\n",
					        param->value, param->line);
			closeOssMixer();
			return -1;
		}

		volume_ossControl = i;
	}

	return 0;
}

static int ensure_oss_open(void)
{
	if ((volume_ossFd < 0 && prepOssMixer(volume_mixerDevice) < 0))
		return -1;
	return 0;
}

static int getOssVolumeLevel() {
	int left, right, level;

	if (ensure_oss_open() < 0)
		return -1;

	if(ioctl(volume_ossFd,MIXER_READ(volume_ossControl),&level) < 0) {
		closeOssMixer();
		WARNING("unable to read volume\n");
		return -1;
	}

	left = level & 0xff;
	right = (level & 0xff00) >> 8;

	if(left!=right) {
		WARNING("volume for left and right is not the same, \"%i\" and "
			"\"%i\"\n",left,right);
	}

	return left;
}

static int changeOssVolumeLevel(FILE * fp, int change, int rel) {
	int current;
	int new;
	int level;

	if (rel) {
		if((current = getOssVolumeLevel()) < 0) {
			commandError(fp, ACK_ERROR_SYSTEM,
                                        "problem getting current volume", NULL);
			return -1;
		}

		new = current+change;
	} else {
		if (ensure_oss_open() < 0)
			return -1;
		new = change;
	}

	if(new<0) new = 0;
	else if(new>100) new = 100;

	level = (new << 8) + new;

	if(ioctl(volume_ossFd,MIXER_WRITE(volume_ossControl),&level) < 0) {
		closeOssMixer();
		commandError(fp, ACK_ERROR_SYSTEM, "problems setting volume",
				NULL);
		return -1;
	}

	return 0;
}
#endif

#ifdef HAVE_ALSA
static void closeAlsaMixer(void) {
	snd_mixer_close(volume_alsaMixerHandle);
	volume_alsaMixerHandle = NULL;
}

static int prepAlsaMixer(char * card) {
	int err;
	snd_mixer_elem_t * elem;
	char * controlName = VOLUME_MIXER_ALSA_CONTROL_DEFAULT;
        ConfigParam * param;

	if((err = snd_mixer_open(&volume_alsaMixerHandle,0))<0) {
		WARNING("problems opening alsa mixer: %s\n",snd_strerror(err));
		return -1;
	}

	if((err = snd_mixer_attach(volume_alsaMixerHandle,card))<0) {
		closeAlsaMixer();
		WARNING("problems problems attaching alsa mixer: %s\n",
			snd_strerror(err));
		return -1;
	}

	if((err = snd_mixer_selem_register(volume_alsaMixerHandle,NULL,NULL))<0) {
		closeAlsaMixer();
		WARNING("problems snd_mixer_selem_register'ing: %s\n",
			snd_strerror(err));
		return -1;
	}

	if((err = snd_mixer_load(volume_alsaMixerHandle))<0) {
		closeAlsaMixer();
		WARNING("problems snd_mixer_selem_register'ing: %s\n",
			snd_strerror(err));
		return -1;
	}

	elem = snd_mixer_first_elem(volume_alsaMixerHandle);

	param = getConfigParam(CONF_MIXER_CONTROL);

	if(param) {
		controlName = param->value;
	}

	while(elem) {
		if(snd_mixer_elem_get_type(elem)==SND_MIXER_ELEM_SIMPLE) {
			if(strcasecmp(controlName,
					snd_mixer_selem_get_name(elem))==0)
			{
				break;
			}
		}
		elem = snd_mixer_elem_next(elem);
	}

	if(elem) {
		volume_alsaElem = elem;
		snd_mixer_selem_get_playback_volume_range(
				volume_alsaElem,
				&volume_alsaMin,&volume_alsaMax);
		return 0;
	}

	WARNING("can't find alsa mixer_control \"%s\"\n",controlName);

	closeAlsaMixer();
	return -1;
}

static int prep_alsa_get_level(long *level)
{
	const char *cmd;
	int err;

	if (!volume_alsaMixerHandle && prepAlsaMixer(volume_mixerDevice)<0)
		return -1;

	if ((err = snd_mixer_handle_events(volume_alsaMixerHandle)) < 0) {
		cmd = "handle_events";
		goto error;
	}
	if((err = snd_mixer_selem_get_playback_volume(volume_alsaElem,
			SND_MIXER_SCHN_FRONT_LEFT, level)) < 0) {
		cmd = "selem_get_playback_volume";
		goto error;
	}
	return 0;
error:
	WARNING("problems getting alsa volume: %s (snd_mixer_%s)\n",
						snd_strerror(err), cmd);
	closeAlsaMixer();
	return -1;
}

static int getAlsaVolumeLevel() {
	int ret;
	long level;
	long max = volume_alsaMax;
	long min = volume_alsaMin;

	if (prep_alsa_get_level(&level) < 0)
		return -1;

	ret = ((volume_alsaSet/100.0)*(max-min)+min)+0.5;
	if(volume_alsaSet>0 && ret==level) {
		ret = volume_alsaSet;
	}
	else ret =  (int)(100*(((float)(level-min))/(max-min))+0.5);

	return ret;
}

static int changeAlsaVolumeLevel(FILE * fp, int change, int rel) {
	float vol;
	long level;
	long test;
	long max = volume_alsaMax;
	long min = volume_alsaMin;
	int err;

	if (prep_alsa_get_level(&level) < 0)
		return -1;

	if (rel) {
		test = ((volume_alsaSet/100.0)*(max-min)+min)+0.5;
		if(volume_alsaSet >= 0 && level==test) {
			vol = volume_alsaSet;
		}
		else vol =  100.0*(((float)(level-min))/(max-min));
		vol+=change;
	}
	else
		vol = change;

	volume_alsaSet = vol+0.5;
	volume_alsaSet = volume_alsaSet>100 ? 100 : 
			(volume_alsaSet<0 ? 0 : volume_alsaSet);

	level = (long)(((vol/100.0)*(max-min)+min)+0.5);
	level = level>max?max:level;
	level = level<min?min:level;

	if((err = snd_mixer_selem_set_playback_volume_all(
				volume_alsaElem,level))<0) {
		commandError(fp, ACK_ERROR_SYSTEM, "problems setting volume",
				NULL);
		WARNING("problems setting alsa volume: %s\n",snd_strerror(err));
		closeAlsaMixer();
		return -1;
	}

	return 0;
}
#endif

static int prepMixer(char * device) {
	switch(volume_mixerType) {
#ifdef HAVE_ALSA
	case VOLUME_MIXER_TYPE_ALSA:
		return prepAlsaMixer(device);
#endif
#ifdef HAVE_OSS
	case VOLUME_MIXER_TYPE_OSS:
		return prepOssMixer(device);
#endif
	}

	return 0;
}

void finishVolume() {
	switch(volume_mixerType) {
#ifdef HAVE_ALSA
	case VOLUME_MIXER_TYPE_ALSA:
		closeAlsaMixer();
		break;
#endif
#ifdef HAVE_OSS
	case VOLUME_MIXER_TYPE_OSS:
		closeOssMixer();
		break;
#endif
	}
}

void initVolume() {
	ConfigParam * param = getConfigParam(CONF_MIXER_TYPE);

	if(param) {
	        if(0);
#ifdef HAVE_ALSA
		else if(strcmp(param->value, VOLUME_MIXER_ALSA)==0) {
			volume_mixerType = VOLUME_MIXER_TYPE_ALSA;
			volume_mixerDevice = VOLUME_MIXER_ALSA_DEFAULT;
		}
#endif
#ifdef HAVE_OSS
		else if(strcmp(param->value, VOLUME_MIXER_OSS)==0) {
			volume_mixerType = VOLUME_MIXER_TYPE_OSS;
			volume_mixerDevice = VOLUME_MIXER_OSS_DEFAULT;
		}
#endif
		else if(strcmp(param->value ,VOLUME_MIXER_SOFTWARE)==0) {
			volume_mixerType = VOLUME_MIXER_TYPE_SOFTWARE;
			volume_mixerDevice = VOLUME_MIXER_SOFTWARE_DEFAULT;
		}
		else {
			ERROR("unknown mixer type %s at line %i\n",
					param->value, param->line);
			exit(EXIT_FAILURE);
		}
	}

	param = getConfigParam(CONF_MIXER_DEVICE);

	if(param) {
		volume_mixerDevice = param->value;
	}
}

void openVolumeDevice() {
	if(prepMixer(volume_mixerDevice)<0) {
		WARNING("using software volume\n");
		volume_mixerType = VOLUME_MIXER_TYPE_SOFTWARE;
	}
}

static int getSoftwareVolume() {
	return volume_softwareSet;
}

int getVolumeLevel() {
	switch(volume_mixerType) {
#ifdef HAVE_ALSA
	case VOLUME_MIXER_TYPE_ALSA:
		return getAlsaVolumeLevel();
#endif
#ifdef HAVE_OSS
	case VOLUME_MIXER_TYPE_OSS:
		return getOssVolumeLevel();
#endif
	case VOLUME_MIXER_TYPE_SOFTWARE:
		return getSoftwareVolume();
	default:
		return -1;
	}
}

static int changeSoftwareVolume(FILE * fp, int change, int rel) {
	int new = change;

	if(rel) new+=volume_softwareSet;

	if(new>100) new = 100;
	else if(new<0) new = 0;

	volume_softwareSet = new;

	/*new = 100.0*(exp(new/50.0)-1)/(M_E*M_E-1)+0.5;*/
	if(new>=100) new = 1000;
	else if(new<=0) new = 0;
	else new = 1000.0*(exp(new/25.0)-1)/(54.5981500331F-1)+0.5;

	setPlayerSoftwareVolume(new);

	return 0;
}

int changeVolumeLevel(FILE * fp, int change, int rel) {
	switch(volume_mixerType) {
#ifdef HAVE_ALSA
	case VOLUME_MIXER_TYPE_ALSA:
		return changeAlsaVolumeLevel(fp,change,rel);
#endif
#ifdef HAVE_OSS
	case VOLUME_MIXER_TYPE_OSS:
		return changeOssVolumeLevel(fp,change,rel);
#endif
	case VOLUME_MIXER_TYPE_SOFTWARE:
		return changeSoftwareVolume(fp,change,rel);
	default:
		return 0;
		break;
	}
}