GTA SA CLoadedCarGroup::PickRandomCar

signed int __thiscall CLoadedCarGroup::PickRandomCar(CLoadedCarGroup *this, char a2, char a3)
{
  signed int v3; // eax@1
  CLoadedCarGroup *v4; // edx@1
  int v5; // ebp@1
  signed int v7; // ebx@6
  int v8; // esi@7
  int *v9; // edi@8
  signed int v10; // eax@10
  CModelCars *v11; // edx@10
  __int16 v12; // cx@10
  int v13; // eax@16
  signed int v14; // ebp@19
  float v15; // ST1C_4@20
  unsigned __int64 v16; // qax@20
  int v17; // esi@20
  signed int i; // ecx@22
  CLoadedCarGroup *v19; // [sp+14h] [bp-38h]@1
  int v20; // [sp+1Ch] [bp-30h]@7
  signed __int16 v21; // [sp+48h] [bp-4h]@7

  v4 = this;
  v5 = 0;
  v19 = this;
  v3 = 0;
  do
  {
    if ( this->m_Array[v3] < 0 )
      break;
    ++v5;
    ++v3;
  }
  while ( v3 < 23 );
  if ( !v5 )
    return -1;
  v7 = 0;
  if ( !a3 )
  {
    v13 = 0;
    if ( v5 > 0 )
    {
      do
        v7 += CModelInfo::ms_modelInfoPtrs[this->m_Array[v13++]]->frq;
      while ( v13 < v5 );
      goto LABEL_18;
    }
    return -1;
  }
  memset(&v20, -1, 0x2Cu);
  v8 = 0;
  v21 = -1;
  if ( v5 <= 0 )
    return -1;
  v9 = &v20;
  while ( 1 )
  {
    v12 = v4->m_Array[v8];
    v11 = CModelInfo::ms_modelInfoPtrs[v4->m_Array[v8]];
    v10 = v11->vclass;
    if ( v10 >= 0 && (v10 <= 2 || v10 == 8) )
    {
      *(_WORD *)v9 = v12;
      v7 += v11->frq;
      v9 = (int *)((char *)v9 + 2);
    }
    ++v8;
    if ( v8 >= v5 )
      break;
    v4 = v19;
  }
LABEL_18:
  if ( !v7 )
    return -1;
  v14 = 0;
  while ( 1 )
  {
    v15 = (long double)v7;
    v16 = (unsigned __int64)((long double)(unsigned __int16)rand() * 0.000030517578 * v15);
    HIDWORD(v16) = v19;
    v17 = (signed __int16)v20;
    if ( !a3 )
      v17 = v19->m_Array[0];
    for ( i = CModelInfo::ms_modelInfoPtrs[v17]->frq; (signed int)v16 > i; i = CModelInfo::ms_modelInfoPtrs[v17]->frq )
    {
      LODWORD(v16) = v16 - i;
      HIDWORD(v16) += 2;
      if ( a3 )
        v17 = *(_WORD *)((char *)&v20 - (char *)v19 + HIDWORD(v16));
      else
        v17 = *HIDWORD(v16);
    }
    if ( !rcgIsModelDisabled(v17)
      && !sub_46A890(v17)
      && !(unsigned __int8)sub_407F80(v17)
      && (!a2 || CModelInfo::ms_modelInfoPtrs[v17]->__parent.__parent.m_wUsageCount < 3) )
      break;
    ++v14;
    if ( v14 >= 10 )
      return -1;
  }
  return v17;
}