/*
    passages.c - Draw the connecting passages
       
    UltraRogue: The Ultimate Adventure in the Dungeons of Doom
    Copyright (C) 1985, 1986, 1992, 1993, 1995 Herb Chong
    All rights reserved.

    Based on "Advanced Rogue"
    Copyright (C) 1984, 1985 Michael Morgan, Ken Dalka
    All rights reserved.

    Based on "Rogue: Exploring the Dungeons of Doom"
    Copyright (C) 1980, 1981 Michael Toy, Ken Arnold and Glenn Wichman
    All rights reserved.

    See the file LICENSE.TXT for full copyright and licensing information.
*/

#include <stdlib.h>
#include "rogue.h"

#define cmov(xy) move((xy).y, (xy).x)

/*
    do_passages()
        Draw all the passages on a level.
*/

void
do_passages(void)
{
    struct rdes *r1, *r2 = NULL;
    int i, j;
    int roomcount;

    static struct rdes rdes[MAXROOMS] =
    {
        {{ 0, 1, 0, 1, 0, 0, 0, 0, 0},
         { 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0},
        {{ 1, 0, 1, 0, 1, 0, 0, 0, 0},
         { 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0},
        {{ 0, 1, 0, 0, 0, 1, 0, 0, 0},
         { 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0},
        {{ 1, 0, 0, 0, 1, 0, 1, 0, 0},
         { 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0},
        {{ 0, 1, 0, 1, 0, 1, 0, 1, 0},
         { 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0},
        {{ 0, 0, 1, 0, 1, 0, 0, 0, 1},
         { 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0},
        {{ 0, 0, 0, 1, 0, 0, 0, 1, 0},
         { 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0},
        {{ 0, 0, 0, 0, 1, 0, 1, 0, 1},
         { 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0},
        {{ 0, 0, 0, 0, 0, 1, 0, 1, 0},
         { 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0}
    };

    /* reinitialize room graph description */

    for (r1 = rdes; r1 < &rdes[MAXROOMS]; r1++)
    {
        for (j = 0; j < MAXROOMS; j++)
            r1->isconn[j] = FALSE;

        r1->ingraph = FALSE;
    }

    /*
     * starting with one room, connect it to a random adjacent room and
     * then pick a new room to start with.
     */

    roomcount = 1;
    r1 = &rdes[rnd(MAXROOMS)];
    r1->ingraph = TRUE;

    do
    {
        j = 0;

        for (i = 0; i < MAXROOMS; i++)
            if (r1->conn[i] && !rdes[i].ingraph && rnd(++j) == 0)
                r2 = &rdes[i];

        /*
         * if no adjacent rooms are outside the graph, pick a new
         * room to look from
         */

        if (j == 0)
            do
            {
                r1 = &rdes[rnd(MAXROOMS)];
            }
            while (!r1->ingraph);

        /*
         * otherwise, connect new room to the graph, and draw a
         * tunnel to it
         */
        else
        {
            r2->ingraph = TRUE;
            i = (int)(r1 - rdes);
            j = (int)(r2 - rdes);
            conn(i, j);
            r1->isconn[j] = TRUE;
            r2->isconn[i] = TRUE;
            roomcount++;
        }
    }
    while (roomcount < MAXROOMS);

    /*
     * attempt to add passages to the graph a random number of times so
     * that there isn't just one unique passage through it.
     */

    for (roomcount = rnd(5); roomcount > 0; roomcount--)
    {
        r1 = &rdes[rnd(MAXROOMS)];  /* a random room to look from */

        /*
         * find an adjacent room not already connected
         */

        j = 0;
        for (i = 0; i < MAXROOMS; i++)
            if (r1->conn[i] && !r1->isconn[i] && rnd(++j) == 0)
                r2 = &rdes[i];

        /*
         * if there is one, connect it and look for the next added
         * passage
         */

        if (j != 0)
        {
            i = (int)(r1 - rdes);
            j = (int)(r2 - rdes);
            conn(i, j);
            r1->isconn[j] = TRUE;
            r2->isconn[i] = TRUE;
        }
    }
}

/*
    conn()
        Draw a corridor from a room in a certain direction.
*/

void
conn(int r1, int r2)
{
    struct room *rpf, *rpt = NULL;
    int    rmt;
    int distance = 0, turn_spot = 0, turn_distance = 0;
    int rm;
    char    direc;
    coord   delt = {0,0}, curr, turn_delta = {0,0}, spos = {0,0}, epos = {0,0};

    if (r1 < r2)
    {
        rm = r1;

        if (r1 + 1 == r2)
            direc = 'r';
        else
            direc = 'd';
    }
    else
    {
        rm = r2;

        if (r2 + 1 == r1)
            direc = 'r';
        else
            direc = 'd';
    }

    rpf = &rooms[rm];

    /*
     * Set up the movement variables, in two cases: first drawing one
     * down.
     */

    if (direc == 'd')
    {
        rmt = rm + 3;   /* room # of dest */
        rpt = &rooms[rmt];  /* room pointer of dest */
        delt.x = 0;    /* direction of move */
        delt.y = 1;
        spos.x = rpf->r_pos.x;  /* start of move */
        spos.y = rpf->r_pos.y;
        epos.x = rpt->r_pos.x;  /* end of move */
        epos.y = rpt->r_pos.y;

        if (!(rpf->r_flags & ISGONE)) /* if not gone pick door pos */
        {
            spos.x += rnd(rpf->r_max.x - 2) + 1;
            spos.y += rpf->r_max.y - 1;
        }

        if (!(rpt->r_flags & ISGONE))
            epos.x += rnd(rpt->r_max.x - 2) + 1;

        distance = abs(spos.y - epos.y) - 1;    /* distance to move */
        turn_delta.y = 0;   /* direction to turn */
        turn_delta.x = (spos.x < epos.x ? 1 : -1);
        turn_distance = abs(spos.x - epos.x);   /* how far to turn */
        turn_spot = rnd(distance - 1) + 1;  /* where turn starts */
    }
    else if (direc == 'r') /* setup for moving right */
    {
        rmt = rm + 1;
        rpt = &rooms[rmt];
        delt.x = 1;
        delt.y = 0;
        spos.x = rpf->r_pos.x;
        spos.y = rpf->r_pos.y;
        epos.x = rpt->r_pos.x;
        epos.y = rpt->r_pos.y;

        if (!(rpf->r_flags & ISGONE))
        {
            spos.x += rpf->r_max.x - 1;
            spos.y += rnd(rpf->r_max.y - 2) + 1;
        }

        if (!(rpt->r_flags & ISGONE))
            epos.y += rnd(rpt->r_max.y - 2) + 1;

        distance = abs(spos.x - epos.x) - 1;
        turn_delta.y = (spos.y < epos.y ? 1 : -1);
        turn_delta.x = 0;
        turn_distance = abs(spos.y - epos.y);
        turn_spot = rnd(distance - 1) + 1;
    }
    else
        debug("Error in connection tables.");

    /*
     * Draw in the doors on either side of the passage or just put #'s if
     * the rooms are gone.
     */

    if (!(rpf->r_flags & ISGONE))
        door(rpf, &spos);
    else
    {
        cmov(spos);
        addch('#');
    }

    if (!(rpt->r_flags & ISGONE))
        door(rpt, &epos);
    else
    {
        cmov(epos);
        addch('#');
    }

    /* Get ready to move... */

    curr.x = spos.x;
    curr.y = spos.y;

    while (distance)
    {
        /* Move to new position */

        curr.x += delt.x;
        curr.y += delt.y;

        /* Check if we are at the turn place, if so do the turn */

        if (distance == turn_spot && turn_distance > 0)
            while (turn_distance--)
            {
                cmov(curr);
                addch(PASSAGE);
                curr.x += turn_delta.x;
                curr.y += turn_delta.y;
            }

        /* Continue digging along */

        cmov(curr);
        addch(PASSAGE);
        distance--;
    }

    curr.x += delt.x;
    curr.y += delt.y;

    if (!ce(curr, epos))
        msg("Warning, connectivity problem on this level.");
}

/*
    door()
        Add a door or possibly a secret door also enters the door in the exits
        array of the room.
*/

void
door(struct room *rm, coord *cp)
{
    char a_door;

    cmov(*cp);

    a_door = (rnd(10)<level - 1 && rnd(100) < 20) ? SECRETDOOR : DOOR;

    addch(a_door);

    rm->r_exit[rm->r_nexits++] = *cp;
}