#include "music.h"

#include "dsp.h"
#include "tsf.h"
#include "tml.h"
#include "mix.h"
#include "sound.h"
#include "log.h"
#include "resources.h"
#include <stdlib.h>

#define TSF_BLOCK 32

struct dsp_midi_song gsong;
struct dsp_filter songfil;

float music_pan = 0.f;

void dsp_midi_fillbuf(struct dsp_midi_song *song, void *out, int n)
{
  soundbyte *o = (soundbyte*)out;
  tml_message *midi = song->midi;

  for (int i = 0; i < n; i += TSF_BLOCK) {
    while (midi && song->time >= midi->time) {
      switch (midi->type) {
	 case TML_PROGRAM_CHANGE:
	   tsf_channel_set_presetnumber(song->sf, midi->channel, midi->program, (midi->channel == 9));
	   break;

	 case TML_NOTE_ON:
	   tsf_channel_note_on(song->sf, midi->channel, midi->key, midi->velocity / 127.f);
	   break;

	 case TML_NOTE_OFF:
	   tsf_channel_note_off(song->sf, midi->channel, midi->key);
	   break;

	 case TML_PITCH_BEND:
	   tsf_channel_set_pitchwheel(song->sf, midi->channel, midi->pitch_bend);
	   break;

	 case TML_CONTROL_CHANGE:
	   tsf_channel_midi_control(song->sf, midi->channel, midi->control, midi->control_value);
	   break;
       }

      midi = midi->next;
    }
    tsf_render_float(song->sf, o, TSF_BLOCK, 0);
    o += TSF_BLOCK*CHANNELS;
    song->time += TSF_BLOCK * (1000.f/SAMPLERATE);
  }

  song->midi = midi;
}

struct bus *musicbus;

void play_song(const char *midi, const char *sf)
{
    long rawlen;
    void *raw = slurp_file(midi, &rawlen);
    
    gsong.midi = tml_load_memory(raw, rawlen);
    if (gsong.midi == NULL) {
        YughWarn("Midi %s not found.", midi);
	free(raw);
        return;
    }
    free(raw);
    
    raw = slurp_file(sf, &rawlen);
    gsong.sf = tsf_load_memory(raw, rawlen);

    if (gsong.sf == NULL) {
        YughWarn("SF2 %s not found.", sf);
	free(raw);
        return;
    }
    free(raw);

    gsong.time = 0.f;

    tsf_set_output(gsong.sf, TSF_STEREO_INTERLEAVED, SAMPLERATE, 0.f);

    // Preset on 10th MIDI channel to use percussion sound bank if possible
    tsf_channel_set_bank_preset(gsong.sf, 9, 128, 0);

    songfil.data = &gsong;
    songfil.filter = dsp_midi_fillbuf;
    filter_to_bus(&songfil);
}

void music_stop()
{
  unplug_filter(&songfil);
}