/*      $NetBSD: shapes.c,v 1.9 2014/06/11 16:47:39 christos Exp $      */

/*-
* Copyright (c) 1992, 1993
*      The Regents of the University of California.  All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Chris Torek and Darren F. Provine.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*      @(#)shapes.c    8.1 (Berkeley) 5/31/93
*/

/*
* Tetris shapes and related routines.
*
* Note that the first 7 are `well known'.
*/

#include <sys/cdefs.h>
#include "tetris.h"

#define TL      -B_COLS-1       /* top left */
#define TC      -B_COLS         /* top center */
#define TR      -B_COLS+1       /* top right */
#define ML      -1              /* middle left */
#define MR      1               /* middle right */
#define BL      B_COLS-1        /* bottom left */
#define BC      B_COLS          /* bottom center */
#define BR      B_COLS+1        /* bottom right */

const struct shape shapes[] = {
       /* 0*/  { 7,  7,        { TL, TC, MR, } },
       /* 1*/  { 1,  8,        { TC, TR, ML, } },
       /* 2*/  { 2,  9,        { ML, MR, BC, } },
       /* 3*/  { 3,  3,        { TL, TC, ML, } },
       /* 4*/  { 4, 12,        { ML, BL, MR, } },
       /* 5*/  { 5, 15,        { ML, BR, MR, } },
       /* 6*/  { 6, 18,        { ML, MR, 2   } },      /* sticks out */
       /* 7*/  { 7,  0,        { TC, ML, BL, } },
       /* 8*/  { 1,  1,        { TC, MR, BR, } },
       /* 9*/  { 2, 10,        { TC, MR, BC, } },
       /*10*/  { 2, 11,        { TC, ML, MR, } },
       /*11*/  { 2,  2,        { TC, ML, BC, } },
       /*12*/  { 4, 13,        { TC, BC, BR, } },
       /*13*/  { 4, 14,        { TR, ML, MR, } },
       /*14*/  { 4,  4,        { TL, TC, BC, } },
       /*15*/  { 5, 16,        { TR, TC, BC, } },
       /*16*/  { 5, 17,        { TL, MR, ML, } },
       /*17*/  { 5,  5,        { TC, BC, BL, } },
       /*18*/  { 6,  6,        { TC, BC, 2*B_COLS } }  /* sticks out */
};

/*
* Return true iff the given shape fits in the given position,
* taking the current board into account.
*/
int
fits_in(const struct shape *shape, int pos)
{
       const int *o = shape->off;

       if (board[pos] || board[pos + *o++] || board[pos + *o++] ||
           board[pos + *o])
               return 0;
       return 1;
}

/*
* Write the given shape into the current board, turning it on
* if `onoff' is 1, and off if `onoff' is 0.
*/
void
place(const struct shape *shape, int pos, int onoff)
{
       const int *o = shape->off;
       onoff = onoff ? shape->color : 0;

       board[pos] = onoff;
       board[pos + *o++] = onoff;
       board[pos + *o++] = onoff;
       board[pos + *o] = onoff;
}