int __fastcall sub_401638(int a1, int a2, int a3, _DWORD *a4)
{
  int result; // r0
  int *v9; // r1
  char *v10; // r7
  int i; // r0
  char v12; // t1
  char *v13; // r6
  int j; // r0
  char v15; // t1
  _DWORD *v16; // [sp+Ch] [bp-338h]
  _BYTE v17[4]; // [sp+10h] [bp-334h] BYREF
  int v18; // [sp+14h] [bp-330h]
  int v19; // [sp+18h] [bp-32Ch]
  int v20; // [sp+30h] [bp-314h] BYREF
  int v21; // [sp+34h] [bp-310h] BYREF
  int v22; // [sp+38h] [bp-30Ch] BYREF
  int v23; // [sp+3Ch] [bp-308h] BYREF
  _BYTE v24[256]; // [sp+40h] [bp-304h] BYREF
  _BYTE v25[256]; // [sp+140h] [bp-204h] BYREF
  _DWORD v26[64]; // [sp+240h] [bp-104h] BYREF
  int v27; // [sp+340h] [bp-4h]

  v27 = dword_401954;
  v23 = 0;
  v21 = 0;
  v22 = 0;
  sub_401130(a1: v25, a2: 256);
  sub_401130(a1: v24, a2: 256);
  v20 = a2;
  sub_401130(a1: v17, a2: 32);
  if ( sub_401C2A(a1: v17) == 0 )
  {
    result = 7;
    switch ( v18 )
    {
      case 1:
        goto LABEL_6;
      case 4:
        if ( v19 == 1 )
LABEL_6:
          v9 = dword_4038D8;
        else
          v9 = (int *)sub_403D98;
        goto LABEL_11;
      case 5:
        v9 = dword_404258;
        goto LABEL_11;
      case 6:
        v9 = dword_401C58;
        goto LABEL_11;
      case 8:
        v9 = dword_4025D8;
LABEL_11:
        sub_401088(a1: 4220928, a2: v9, a3: 1216);
        if ( sub_401C40(a1: 4220928) != 0 )
        {
          result = 8;
          goto LABEL_24;
        }
        if ( MEMORY[0x406824] != 2048 )
        {
          result = 5;
          goto LABEL_24;
        }
        v16 = a4;
        v10 = (char *)v26;
        sub_4010EC(a1: (char *)v26 + 3, a2: 253);
        LOWORD(v26[0]) = MEMORY[0x406830];
        LOBYTE(v21) = MEMORY[0x406832];
        BYTE1(v21) = MEMORY[0x406831];
        BYTE2(v21) = MEMORY[0x406830];
        sub_401088(a1: v26, a2: 4220980, a3: 256);
        for ( i = 255; i != -1; --i )
        {
          v12 = *v10++;
          v24[i] = v12;
        }
        v13 = (char *)v26;
        sub_401088(a1: v26, a2: 4221236, a3: 256);
        a4 = v16;
        for ( j = 255; j != -1; --j )
        {
          v15 = *v13++;
          v25[j] = v15;
        }
        if ( sub_401A54(a1: -1593835472, a2: 2048, a3: &v22) == 0 )
        {
          v26[1] = &v21;
          v26[4] = v25;
          v26[5] = 256;
          v26[7] = v24;
          v26[8] = 256;
          v26[6] = -1073741008;
          v26[3] = -805306064;
          v26[0] = -805305808;
          v26[2] = 3;
          if ( sub_401B86(a1: v22, a2: v26, a3: 3) == 0
            && sub_401A24(a1: &v23, a2: 1616970288, a3: 1, a4: 2048) == 0
            && sub_401BB6(a1: v23, a2: v22) == 0 )
          {
            break;
          }
        }
        result = 9;
        goto LABEL_24;
      case 11:
      case 12:
      case 13:
      case 14:
      case 15:
      case 16:
      case 17:
        abort();
      default:
        goto LABEL_24;
    }
    goto LABEL_26;
  }
  result = 6;
LABEL_24:
  while ( dword_401954 != v27 )
  {
    ((void (__fastcall *)(int, int))loc_401958)(a1: result, a2: dword_401954 - v27);
LABEL_26:
    if ( sub_401A84(a1: v23, a2: 0, a3: 0, a4: a1, a5: a2, a6: a3, a7: &v20) != 0 )
    {
      if ( v22 != 0 )
        sub_401AF6();
      if ( v23 != 0 )
        sub_401AD6();
      result = 10;
    }
    else
    {
      *a4 = v20;
      if ( v22 != 0 )
        sub_401AF6();
      if ( v23 != 0 )
        sub_401AD6();
      result = 0;
    }
  }
  return result;
}