/*
 * This file is part of Baritone.
 *
 * Baritone is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Baritone 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Baritone.  If not, see <https://www.gnu.org/licenses/>.
 */

package baritone.pathing.calc;

import baritone.pathing.goals.Goal;
import baritone.pathing.path.IPath;
import net.minecraft.util.math.BlockPos;

import java.util.Optional;

/**
 * Generic path finder interface
 *
 * @author leijurv
 */
public interface IPathFinder {

    BlockPos getStart();

    Goal getGoal();

    /**
     * Calculate the path in full. Will take several seconds.
     *
     * @return The final path
     */
    Optional<IPath> calculate(long timeout);

    /**
     * Intended to be called concurrently with calculatePath from a different thread to tell if it's finished yet
     *
     * @return Whether or not this finder is finished
     */
    boolean isFinished();

    /**
     * Called for path rendering. Returns a path to the most recent node popped from the open set and considered.
     *
     * @return The temporary path
     */
    Optional<IPath> pathToMostRecentNodeConsidered();

    /**
     * The best path so far, according to the most forgiving coefficient heuristic (the reason being that that path is
     * most likely to represent the true shape of the path to the goal, assuming it's within a possible cost heuristic.
     * That's almost always a safe assumption, but in the case of a nearly impossible path, it still works by providing
     * a theoretically plausible but practically unlikely path)
     *
     * @return The temporary path
     */
    Optional<IPath> bestPathSoFar();
}