/**
 * @file dist.cpp
 * @brief Routines to calculate PCB editor auto routing distances.
 */

/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 1992-2012 KiCad Developers, see AUTHORS.txt for contributors.
 *
 * First copyright (C) Randy Nevin, 1989 (see PCBCA package)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */
#include <autorout.h>
#include <cell.h>


/* The tables of distances and keep out areas are established on the basis of a
 * 50 units grid size (the pitch between the cells is 50 units).
 * The actual distance could be computed by a scaling factor, but this is
 * not needed, we can use only reduced values
 */

 /* calculate approximate distance (manhattan distance)
 */
int GetApxDist( int r1, int c1, int r2, int c2 )
{
    int d1, d2; /* row and column deltas */

    if( ( d1 = r1 - r2 ) < 0 ) /* get absolute row delta */
        d1 = -d1;

    if( ( d2 = c1 - c2 ) < 0 ) /* get absolute column delta */
        d2 = -d2;

    return ( d1+d2 ) * 50;
}


/* distance to go thru a cell (en mils) */
static const int dist[10][10] =
{ /* OT=Otherside, OR=Origin (source) cell */
/*..........N, NE,  E, SE,  S, SW,  W, NW,   OT, OR */
/* N  */ { 50, 60, 35, 60, 99, 60, 35, 60,   12, 12 },
/* NE */ { 60, 71, 60, 71, 60, 99, 60, 71,   23, 23 },
/* E  */ { 35, 60, 50, 60, 35, 60, 99, 60,   12, 12 },
/* SE */ { 60, 71, 60, 71, 60, 71, 60, 99,   23, 23 },
/* S  */ { 99, 60, 35, 60, 50, 60, 35, 60,   12, 12 },
/* SW */ { 60, 99, 60, 71, 60, 71, 60, 71,   23, 23 },
/* W  */ { 35, 60, 99, 60, 35, 60, 50, 60,   12, 12 },
/* NW */ { 60, 71, 60, 99, 60, 71, 60, 71,   23, 23 },

/* OT */ { 12, 23, 12, 23, 12, 23, 12, 23,   99, 99 },
/* OR */ { 99, 99, 99, 99, 99, 99, 99, 99,   99, 99 }
};

/* penalty for extraneous holes and corners, scaled by sharpness of turn */
static const int penalty[10][10] =
{ /* OT=Otherside, OR=Origin (source) cell */
/*......... N, NE,  E, SE,  S, SW,  W, NW,   OT, OR */
/* N  */ {  0,  5, 10, 15, 20, 15, 10,  5,   50, 0 },
/* NE */ {  5,  0,  5, 10, 15, 20, 15, 10,   50, 0 },
/* E  */ { 10,  5,  0,  5, 10, 15, 20, 15,   50, 0 },
/* SE */ { 15, 10,  5,  0,  5, 10, 15, 20,   50, 0 },
/* S  */ { 20, 15, 10,  5,  0,  5, 10, 15,   50, 0 },
/* SW */ { 15, 20, 15, 10,  5,  0,  5, 10,   50, 0 },
/* W  */ { 10, 15, 20, 15, 10,  5,  0,  5,   50, 0 },
/* NW */ {  5, 10, 15, 20, 15, 10,  5,  0,   50, 0 },

/* OT */ { 50, 50, 50, 50, 50, 50, 50, 50,  100, 0 },
/* OR */ {  0,  0,  0,  0,  0,  0,  0,  0,    0, 0 }
};

/* penalty pour directions preferencielles */
#define PN 20
static const int dir_penalty_TOP[10][10] =
{
/* OT=Otherside, OR=Origin (source) cell */
/*......... N, NE,  E, SE,  S, SW,  W, NW,   OT, OR */
/* N  */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 },
/* NE */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 },
/* E  */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 },
/* SE */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 },
/* S  */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 },
/* SW */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 },
/* W  */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 },
/* NW */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 },

/* OT */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 },
/* OR */ { PN,  0,  0,  0, PN,  0,  0,  0,    0, 0 }
};

static int dir_penalty_BOTTOM[10][10] =
{
/* OT=Otherside, OR=Origin (source) cell */
/*......... N, NE,  E, SE,  S, SW,  W, NW,   OT, OR */
/* N  */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 },
/* NE */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 },
/* E  */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 },
/* SE */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 },
/* S  */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 },
/* SW */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 },
/* W  */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 },
/* NW */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 },

/* OT */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 },
/* OR */ {  0,  0, PN,  0,  0,  0, PN,  0,    0, 0 }
};

/*
** x is the direction to enter the cell of interest.
** y is the direction to exit the cell of interest.
** z is the direction to really exit the cell, if y=FROM_OTHERSIDE.
**
** return the distance of the trace through the cell of interest.
** the calculation is driven by the tables above.
*/


/* calculate distance (with penalty) of a trace through a cell
*/
int CalcDist(int x,int y,int z ,int side )
{
    int adjust, ldist;

    adjust = 0; /* set if hole is encountered */

    if( x == EMPTY )
        x = 10;

    if( y == EMPTY )
    {
        y = 10;
    }
    else if( y == FROM_OTHERSIDE )
    {
        if( z == EMPTY )
            z = 10;

        adjust = penalty[x-1][z-1];
    }

    ldist = dist[x-1][y-1] + penalty[x-1][y-1] + adjust;

    if( Nb_Sides )
    {
        if( side == BOTTOM )
            ldist += dir_penalty_TOP[x-1][y-1];

        if( side == TOP )
            ldist += dir_penalty_BOTTOM[x-1][y-1];
    }

    return ldist * 10;
}
