#include "cell.h"

#include <stdlib.h>

#define DR_FLAC_IMPLEMENTATION
#include "dr_flac.h"

static int flac_calc_size(drflac *flac, drflac_uint64 frames, size_t *out_bytes)
{
  if (!flac || !out_bytes)
    return -1;

  if (flac->channels == 0)
    return -1;

  size_t bytes_per_frame = (size_t)flac->channels * sizeof(drflac_int32);
  if (frames > SIZE_MAX / bytes_per_frame)
    return -1;

  *out_bytes = (size_t)(frames * bytes_per_frame);
  return 0;
}

static JSValue flac_make_info(JSContext *js, drflac *flac)
{
  JSValue obj = JS_NewObject(js);
  JS_SetPropertyStr(js, obj, "channels", JS_NewInt32(js, flac->channels));
  JS_SetPropertyStr(js, obj, "sample_rate", JS_NewInt32(js, flac->sampleRate));
  JS_SetPropertyStr(js, obj, "bits_per_sample", JS_NewInt32(js, flac->bitsPerSample));
  JS_SetPropertyStr(js, obj, "total_pcm_frames", JS_NewFloat64(js, (double)flac->totalPCMFrameCount));
  JS_SetPropertyStr(js, obj, "decoded_bytes_per_frame",
    JS_NewInt32(js, (int)((size_t)flac->channels * sizeof(drflac_int32))));
  JS_SetPropertyStr(js, obj, "format", JS_NewString(js, "s32"));
  return obj;
}

JSC_CCALL(flac_info,
  size_t len;
  void *data = js_get_blob_data(js, &len, argv[0]);
  if (data == -1)
    return JS_EXCEPTION;

  if (!data)
    return JS_ThrowReferenceError(js, "invalid FLAC data");

  drflac *flac = drflac_open_memory(data, len, NULL);
  if (!flac)
    return JS_ThrowReferenceError(js, "invalid FLAC data");

  JSValue info = flac_make_info(js, flac);
  drflac_close(flac);
  return info;
)

JSC_CCALL(flac_decode,
  size_t len;
  void *data = js_get_blob_data(js, &len, argv[0]);
  if (data == -1)
    return JS_EXCEPTION;
  if (!data)
    return JS_ThrowTypeError(js, "flac.decode expects a blob with data");

  drflac *flac = drflac_open_memory(data, len, NULL);
  if (!flac)
    return JS_ThrowReferenceError(js, "invalid FLAC data");

  size_t pcm_bytes;
  size_t bytes_per_frame = (size_t)flac->channels * sizeof(float);
  
  if (flac->totalPCMFrameCount > SIZE_MAX / bytes_per_frame) {
    drflac_close(flac);
    return JS_ThrowRangeError(js, "FLAC data too large to decode");
  }
  pcm_bytes = (size_t)(flac->totalPCMFrameCount * bytes_per_frame);

  float *pcm = NULL;
  if (pcm_bytes > 0) {
    pcm = malloc(pcm_bytes);
    if (!pcm) {
      drflac_close(flac);
      return JS_ThrowOutOfMemory(js);
    }
  }

  drflac_uint64 frames_read = 0;
  if (pcm_bytes > 0)
    frames_read = drflac_read_pcm_frames_f32(flac, flac->totalPCMFrameCount, pcm);

  size_t bytes_read = 0;
  if (pcm_bytes > 0)
    bytes_read = (size_t)(frames_read * bytes_per_frame);

  JSValue result = flac_make_info(js, flac);
  
  // Update format info
  JS_SetPropertyStr(js, result, "format", JS_NewString(js, "f32"));
  JS_SetPropertyStr(js, result, "decoded_bytes_per_frame", JS_NewInt32(js, (int)bytes_per_frame));
  
  JSValue blob = js_new_blob_stoned_copy(js, pcm, bytes_read);
  JS_SetPropertyStr(js, result, "pcm", blob);
  free(pcm);
  drflac_close(flac);
  return result;
)

static const JSCFunctionListEntry js_flac_funcs[] = {
  MIST_FUNC_DEF(flac, info, 1),
  MIST_FUNC_DEF(flac, decode, 1)
};

CELL_USE_FUNCS(js_flac_funcs)