package dk.daoas.adressevedligehold.tasks;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import dk.daoas.adressevedligehold.tasks.Task.TaskBean;
import dk.daoas.adressevedligehold.tasks.Task.TaskState;

public class TaskManager {
	
	public static final String TASKMANAGER = "TASKMANAGER";
	
	ExecutorService executor = Executors.newFixedThreadPool(1);
	
	private int nextId = 1;

	
	private ArrayList<Task> tasks = new ArrayList<Task>();
	private HashMap<Integer, Task> taskIdMap = new HashMap<Integer,Task>();

	private Task currentTask;
	
	public synchronized List<TaskBean> getTasks() {
		ArrayList<TaskBean> tmpList = new ArrayList<TaskBean>();
		for (Task t : tasks) {
			tmpList.add( t.getTaskBean() );
		}
		
		Collections.reverse(tmpList);
		
		return tmpList;
	}
	
	public void setCurrentTask(Task task) {
		this.currentTask = task;
	}
	
	public Task getCurrentTask() {
		return this.currentTask;
	}
	
	public Task getTaskById(int id) {
		return taskIdMap.get(id);
	}
	
	void shutDown() {
		if (currentTask != null) {
			currentTask.doAbort();	
		}
		
		executor.shutdownNow();
	}
	
	public synchronized void removeTask(Task removeTask) {
		if (removeTask.state == TaskState.STATE_QUEUED) {
			removeTask.doAbort();
		}
		
		if (removeTask.state == TaskState.STATE_ABORTED || removeTask.state == TaskState.STATE_DONE || removeTask.state == TaskState.STATE_QUEUED) {
			taskIdMap.remove( removeTask.getId() );
			tasks.remove(removeTask);
			return;
		}
		
		
		throw new RuntimeException("Cant remove task in current state:" + removeTask.state);
		
	}
	
	public synchronized void submitTask(Task newTask) {
		int id = getNextTaskid();
		newTask.setId(id);
		
		newTask.setManager(this);
		
		taskIdMap.put(id, newTask);
		tasks.add(newTask);
		executor.submit(newTask);
	}
	
	private synchronized int getNextTaskid() {
		return nextId++;
	}
	

}