TwistyPuzzleLib

  private static final int[][] CORNER_MAP = new int[][]

      {

          {0,4,7,1,2,3,5,6},

          {2,0,1,6,3,4,7,5},

          {7,1,0,4,5,6,2,3},

          {1,6,2,0,7,5,3,4},

          {4,3,5,7,0,2,6,1},

          {3,2,6,5,4,0,1,7},

          {5,7,4,3,6,1,0,2},

          {6,5,3,2,1,7,4,0}

      };

  private static final int[][] EDGE_MAP = new int[][]

      {

          {0,3,5,1,4,7,2,6},

          {3,0,1,5,2,6,4,7},

          {5,1,0,3,7,4,6,2},

          {1,5,3,0,6,2,7,4},

          {2,4,7,6,0,1,3,5},

          {7,6,2,4,1,0,5,3},

          {4,2,6,7,3,5,0,1},

          {6,7,4,2,5,3,1,0}

      };

  private static boolean mUpper;

///////////////////////////////////////////////////////////////////////////////////////////////////

  public static void setUpper(boolean upper)

    {

    mUpper = upper;

    }

///////////////////////////////////////////////////////////////////////////////////////////////////

// if mUpper==true, then the edge3 is the 'half-fixed' front edge. Remove it from the permutation.

// Otherwise edge1 is the one; remove it.

  public static int[] edgePermTo7(int[] perm, boolean upper)

    {

    int val;

    int[] ret = new int[7];

    if( upper )

      {

      ret[0] = perm[0];

      ret[1] = perm[1];

      ret[2] = perm[2];

      ret[3] = perm[4];

      ret[4] = perm[5];

      ret[5] = perm[6];

      ret[6] = perm[7];

      val = perm[3];

      }

    else

      {

      ret[0] = perm[0];

      ret[1] = perm[2];

      ret[2] = perm[3];

      ret[3] = perm[4];

      ret[4] = perm[5];

      ret[5] = perm[6];

      ret[6] = perm[7];

      val = perm[1];

      }

    for(int i=0; i<7; i++)

      if( ret[i]>val ) ret[i]--;

    return ret;

    }

///////////////////////////////////////////////////////////////////////////////////////////////////

  private static int[] edgePermTo8(int[] perm, boolean inPlace)

    {

    int[] ret = new int[8];

    if( mUpper )

      {

      int val = inPlace ? 3:1;

      ret[0] = perm[0]; if( ret[0]>=val ) ret[0]++;

      ret[1] = perm[1]; if( ret[1]>=val ) ret[1]++;

      ret[2] = perm[2]; if( ret[2]>=val ) ret[2]++;

      ret[3] = val;

      ret[4] = perm[3]; if( ret[4]>=val ) ret[4]++;

      ret[5] = perm[4]; if( ret[5]>=val ) ret[5]++;

      ret[6] = perm[5]; if( ret[6]>=val ) ret[6]++;

      ret[7] = perm[6]; if( ret[7]>=val ) ret[7]++;

      }

    else

      {

      int val = inPlace ? 1:3;

      ret[0] = perm[0]; if( ret[0]>=val ) ret[0]++;

      ret[1] = val;

      ret[2] = perm[1]; if( ret[2]>=val ) ret[2]++;

      ret[3] = perm[2]; if( ret[3]>=val ) ret[3]++;

      ret[4] = perm[3]; if( ret[4]>=val ) ret[4]++;

      ret[5] = perm[4]; if( ret[5]>=val ) ret[5]++;

      ret[6] = perm[5]; if( ret[6]>=val ) ret[6]++;

      ret[7] = perm[6]; if( ret[7]>=val ) ret[7]++;

      }

    return ret;

    }

///////////////////////////////////////////////////////////////////////////////////////////////////

///////////////////////////////////////////////////////////////////////////////////////////////////

  private int findIndex(int[] table, int value)

    {

    for(int i=0; i<8; i++)

      if( table[i]==value ) return i;

    return -1;

    }

///////////////////////////////////////////////////////////////////////////////////////////////////

  private boolean isFrontEdgeInItsPlace(int[] perm)

    {

    return perm[mUpper ? 3 : 1]==0;

    }

    int cornerPermNum = index%20160;

    index /= 20160;

    boolean inPlace = ((index%2)==0);

    int edgePermNum = index/2;

    int[] corner_perm = new int[8];

    TablebaseHelpers.getPermutationFromNum(corner_perm,8,cornerPermNum);

    int[] edge_perm7 = new int[7];

    TablebaseHelpers.getPermutationFromNum(edge_perm7,7,edgePermNum);

    int[] edge_perm8 = edgePermTo8(edge_perm7,inPlace);

    int[] quats = new int[18];

    for(int i=0; i<8; i++)

      {

      int q = CORNER_MAP[i][corner_perm[i]];

      quats[i] = q;

      }

    for(int i=0; i<8; i++)

      {

      int q = EDGE_MAP[i][edge_perm8[i]];

      quats[i+8] = q;

      }

    return quats;

    int[] corner_perm = new int[8];

    int[] edge_perm8  = new int[8];

    for(int i=0; i<8; i++)

      {

      corner_perm[i] = findIndex( CORNER_MAP[i], quats[i  ]);

      edge_perm8[i]  = findIndex( EDGE_MAP[i]  , quats[i+8]);

      }

    int[] edge_perm7 = edgePermTo7(edge_perm8,mUpper);

    int corner_perm_num = TablebaseHelpers.computePermutationNum(corner_perm);

    int edge_perm_num = TablebaseHelpers.computePermutationNum(edge_perm7);

    boolean inPlace = isFrontEdgeInItsPlace(edge_perm8);

    return corner_perm_num + 20160*( (inPlace?0:1) + 2*edge_perm_num);