/*      $OpenBSD: move.c,v 1.13 2016/08/27 02:02:44 guenther Exp $      */
/*      $NetBSD: move.c,v 1.4 1995/04/22 10:08:58 cgd Exp $     */

/*
 * Copyright (c) 1980, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * 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.
 */

#include <sys/time.h>
#include <ctype.h>
#include <poll.h>
#include <termios.h>
#include <unistd.h>

#include "robots.h"

#define ESC     '\033'

/*
 * get_move:
 *      Get and execute a move from the player
 */
void
get_move(void)
{
        int     c;
        int retval;
        struct timespec t, tn;
#ifdef FANCY
        int lastmove;
#endif

        if (Waiting)
                return;

#ifdef  FANCY
        if (Pattern_roll) {
                if (Next_move >= Move_list)
                        lastmove = *Next_move;
                else
                        lastmove = -1;  /* flag for "first time in" */
        }
#endif
        if (Real_time) {
                t = tv;
                clock_gettime(CLOCK_MONOTONIC, &tn);
        }
        for (;;) {
                if (Teleport && must_telep())
                        goto teleport;
                if (Running)
                        c = Run_ch;
                else if (Count != 0)
                        c = Cnt_move;
#ifdef  FANCY
                else if (Num_robots > 1 && Stand_still)
                        c = '>';
                else if (Num_robots > 1 && Pattern_roll) {
                        if (*++Next_move == '\0') {
                                if (lastmove < 0)
                                        goto over;
                                Next_move = Move_list;
                        }
                        c = *Next_move;
                        mvaddch(0, 0, c);
                        if (c == lastmove)
                                goto over;
                }
#endif
                else {
over:
                        if (Real_time) {
                                struct pollfd pfd[1];

                                pfd[0].fd = STDIN_FILENO;
                                pfd[0].events = POLLIN;
                                retval = ppoll(pfd, 1, &t, NULL);
                                if (retval > 0)
                                        c = getchar();
                                else    /* Don't move if timed out or error */
                                        c = ' ';
                        } else {
                                c = getchar();
                                /* Can't use digits in real time mode, or digit/ESC
                                 * is an effective way to stop the game.
                                 */
                                if (isdigit(c)) {
                                        Count = (c - '0');
                                        while (isdigit(c = getchar()))
                                                Count = Count * 10 + (c - '0');
                                        if (c == ESC)
                                                goto over;
                                        Cnt_move = c;
                                        if (Count)
                                                leaveok(stdscr, TRUE);
                                }
                        }
                }

                switch (c) {
                  case ' ':
                  case '.':
                        if (do_move(0, 0))
                                goto ret;
                        break;
                  case 'y':
                        if (do_move(-1, -1))
                                goto ret;
                        break;
                  case 'k':
                        if (do_move(-1, 0))
                                goto ret;
                        break;
                  case 'u':
                        if (do_move(-1, 1))
                                goto ret;
                        break;
                  case 'h':
                        if (do_move(0, -1))
                                goto ret;
                        break;
                  case 'l':
                        if (do_move(0, 1))
                                goto ret;
                        break;
                  case 'b':
                        if (do_move(1, -1))
                                goto ret;
                        break;
                  case 'j':
                        if (do_move(1, 0))
                                goto ret;
                        break;
                  case 'n':
                        if (do_move(1, 1))
                                goto ret;
                        break;
                  case 'Y': case 'U': case 'H': case 'J':
                  case 'K': case 'L': case 'B': case 'N':
                  case '>':
                        Running = TRUE;
                        if (c == '>')
                                Run_ch = ' ';
                        else
                                Run_ch = tolower(c);
                        leaveok(stdscr, TRUE);
                        break;
                  case 'q':
                  case 'Q':
                        if (query("Really quit?"))
                                quit(0);
                        refresh();
                        break;
                  case 'w':
                  case 'W':
                        Waiting = TRUE;
                        leaveok(stdscr, TRUE);
#ifndef NCURSES_VERSION
                        flushok(stdscr, FALSE);
#endif
                        goto ret;
                  case 't':
                  case 'T':
teleport:
                        Running = FALSE;
                        mvaddch(My_pos.y, My_pos.x, ' ');
                        My_pos = *rnd_pos();
                        mvaddch(My_pos.y, My_pos.x, PLAYER);
                        leaveok(stdscr, FALSE);
                        refresh();
                        flushinp();
                        goto ret;
                  case CTRL('L'):
                        wrefresh(curscr);
                        break;
                  case EOF:
                        quit(0);
                        break;
                  default:
                        beep();
                        reset_count();
                        break;
                }
                if (Real_time) {
                        /* Update current time. */
                        clock_gettime(CLOCK_MONOTONIC, &t);

                        /* Check whether tv time has passed. */
                        timespecadd(&tn, &tv, &tn);
                        if (timespeccmp(&tn, &t, <))
                                goto ret;

                        /* Keep the difference otherwise. */
                        timespecsub(&tn, &t, &t);
                }
        }
ret:
        if (Count > 0)
                if (--Count == 0)
                        leaveok(stdscr, FALSE);
}

/*
 * must_telep:
 *      Must I teleport; i.e., is there anywhere I can move without
 * being eaten?
 */
bool
must_telep(void)
{
        int             x, y;
        static COORD    newpos;

#ifdef  FANCY
        if (Stand_still && Num_robots > 1 && eaten(&My_pos))
                return TRUE;
#endif

        for (y = -1; y <= 1; y++) {
                newpos.y = My_pos.y + y;
                if (newpos.y <= 0 || newpos.y >= Y_FIELDSIZE)
                        continue;
                for (x = -1; x <= 1; x++) {
                        newpos.x = My_pos.x + x;
                        if (newpos.x <= 0 || newpos.x >= X_FIELDSIZE)
                                continue;
                        if (Field[newpos.y][newpos.x] > 0)
                                continue;
                        if (!eaten(&newpos))
                                return FALSE;
                }
        }
        return TRUE;
}

/*
 * do_move:
 *      Execute a move
 */
bool
do_move(int dy, int dx)
{
        static COORD    newpos;

        newpos.y = My_pos.y + dy;
        newpos.x = My_pos.x + dx;
        if (newpos.y <= 0 || newpos.y >= Y_FIELDSIZE ||
            newpos.x <= 0 || newpos.x >= X_FIELDSIZE ||
            Field[newpos.y][newpos.x] > 0 || eaten(&newpos)) {
                if (Running) {
                        Running = FALSE;
                        leaveok(stdscr, FALSE);
                        move(My_pos.y, My_pos.x);
                        refresh();
                } else {
                        beep();
                        reset_count();
                }
                return FALSE;
        }
        else if (dy == 0 && dx == 0)
                return TRUE;
        mvaddch(My_pos.y, My_pos.x, ' ');
        My_pos = newpos;
        mvaddch(My_pos.y, My_pos.x, PLAYER);
        if (!jumping())
                refresh();
        return TRUE;
}

/*
 * eaten:
 *      Player would get eaten at this place
 */
bool
eaten(COORD *pos)
{
        int     x, y;

        for (y = pos->y - 1; y <= pos->y + 1; y++) {
                if (y <= 0 || y >= Y_FIELDSIZE)
                        continue;
                for (x = pos->x - 1; x <= pos->x + 1; x++) {
                        if (x <= 0 || x >= X_FIELDSIZE)
                                continue;
                        if (Field[y][x] == 1)
                                return TRUE;
                }
        }
        return FALSE;
}

/*
 * reset_count:
 *      Reset the count variables
 */
void
reset_count(void)
{
        Count = 0;
        Running = FALSE;
        leaveok(stdscr, FALSE);
        refresh();
}

/*
 * jumping:
 *      See if we are jumping, i.e., we should not refresh.
 */
bool
jumping(void)
{
        return (Jump && (Count || Running || Waiting));
}