package com.chinaztt.mes.aps.core.solver;

import com.chinaztt.mes.aps.core.domain.Task;
import org.optaplanner.core.impl.domain.variable.listener.VariableListener;
import org.optaplanner.core.impl.score.director.ScoreDirector;

import java.time.LocalDateTime;
import java.util.*;

/**
 * @Author: zhangxy
 * @Date: 2020-10-19 20:36
 */
public class StartTimeUpdatingVariableListener implements VariableListener<Task> {
	private Set<Long> idSet = new HashSet<>();

	@Override
	public void beforeEntityAdded(ScoreDirector scoreDirector, Task task) {

	}

	@Override
	public void afterEntityAdded(ScoreDirector scoreDirector, Task task) {
		updatePlanStartTime(scoreDirector, task);
	}

	@Override
	public void beforeVariableChanged(ScoreDirector scoreDirector, Task task) {

	}

	@Override
	public void afterVariableChanged(ScoreDirector scoreDirector, Task task) {
		this.updatePlanStartTime(scoreDirector, task);
	}

	@Override
	public void beforeEntityRemoved(ScoreDirector scoreDirector, Task task) {

	}

	@Override
	public void afterEntityRemoved(ScoreDirector scoreDirector, Task task) {

	}


	protected void updatePlanStartTime(ScoreDirector scoreDirector, Task sourceTask) {
		idSet.clear();
		Queue<Task> uncheckedSuccessorQueue = new ArrayDeque<>();
		uncheckedSuccessorQueue.add(sourceTask);
		while (!uncheckedSuccessorQueue.isEmpty()) {
			Task task = uncheckedSuccessorQueue.remove();
			if (idSet.contains(task.getId())) {
				continue;
			}
			boolean updated = doUpdate(scoreDirector, task);
			if (updated) {
				idSet.add(task.getId());
				if (task.getNextTask() != null) {
					uncheckedSuccessorQueue.add(task.getNextTask());
				}
				if (task.getSuccessorOfRouting() != null) {
					uncheckedSuccessorQueue.add(task.getSuccessorOfRouting());
				}
			}
		}
	}


	protected boolean doUpdate(ScoreDirector scoreDirector, Task task) {
		LocalDateTime now = LocalDateTime.now();
		LocalDateTime time1 = task.getPreviousTaskOrResource() == null ? now : task.getPreviousTaskOrResource().getPlanEndTime();
		LocalDateTime time2 = task.getPredecessorOfRouting() == null ? now : task.getPredecessorOfRouting().getPlanEndTime();

		LocalDateTime maxTime = time1.compareTo(time2) >= 0 ? time1 : time2;
		if (Objects.equals(maxTime, task.getPlanStartTime())) {
			return false;
		}
		scoreDirector.beforeVariableChanged(task, "planStartTime");
		task.setPlanStartTime(maxTime);
		scoreDirector.afterVariableChanged(task, "planStartTime");
		return true;
	}


}