#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>

#include <pulse/simple.h>
#include <pulse/error.h>
#include <pulse/gccmacro.h>
#include <pulse/pulseaudio.h>

#define BUFSIZE 1024
#define UINT32_MAX  (0xffffffff)

struct pa_simple {
    pa_threaded_mainloop *mainloop;
    pa_context *context;
    pa_stream *stream;
    pa_stream_direction_t direction;

    const void *read_data;
    size_t read_index, read_length;

    int operation_success;
};
int indexV = -1;

static void pm_default_sink_info_callback (pa_context *c,const pa_sink_info *info,int eol,void *userdata) {
    if (eol > 0)
        return;
    else {
        indexV = info->index;
        printf("#  set default sink to %d\n",indexV);
    }
}

static void pm_server_info_callback (pa_context *c,const pa_server_info *info,void *userdata) {
    printf("#  server info \n");
    pa_operation *operation;
    if (info == NULL) {
        printf("No PulseAudio Server\n");
        return;
    }
    if (!(operation = pa_context_get_sink_info_by_name (c,info->default_sink_name,pm_default_sink_info_callback,userdata) )) {
    }
}

int setVolume(float volume){
    static pa_sample_spec ss;
        ss.format = PA_SAMPLE_S16LE;
        ss.rate = 44100;
        ss.channels = 2;
    int error;
    pa_simple *s = NULL;
    if (!(s = pa_simple_new(NULL, "thinta", PA_STREAM_PLAYBACK, NULL, "playback", &ss, NULL, NULL, &error))) {
        fprintf(stderr, __FILE__": pa_simple_new() failed: %s\n", pa_strerror(error));
        exit(-1);
    }
    printf("*  connected to server\n");

    printf("*  requesting server info\n");
    pa_context_get_server_info (s->context, pm_server_info_callback, NULL);
    printf("*  waiting for response\n");
    while(indexV == -1){usleep(100);} //waiting for callback to set default-sink-index

    pa_cvolume vol;
    printf("*  Linear Volume: %f\n",volume);
    pa_cvolume_set(&vol, ss.channels,pa_sw_volume_from_linear(volume));

    printf("-> got default sink.. changing volume!\n");
    pa_context_set_sink_volume_by_index(s->context, indexV, &vol, NULL, NULL);

    indexV = -1;
    pa_simple_free(s);
    return 0;
}

int main(){ setVolume(0.1); }