package simulator.lists.slotList;


import java.util.ArrayList;
import java.util.Collection;

import schedframe.resources.ResourceStateDescription;
import schedframe.resources.units.ResourceUnit;
import schedframe.scheduling.TimeResourceAllocation;
import schedframe.scheduling.utils.ResourceParameterName;


/**
 * 
 * @author Marcin Krystek
 *
 */
public class SlotsGantt extends ArrayList<TimeResourceAllocation>{

	private static final long serialVersionUID = -4334870725617831686L;

	public SlotsGantt(){
		super();
	}
	
	public SlotsGantt(Collection<TimeResourceAllocation> collection){
		super(collection);
	}
	
	public void accept(SlotsGanttIterator iterator){
		iterator.visit(this);
	}
	
	/**
	 * Checks whether a slot can added to the Slot Gannt
	 * @param tra a slot to be checked (contains required amount of resources and time period)
	 * @return true if the slot fits to available resources; false otherwise
	 * 
	 * @author Ariel
	 */
	public boolean checkSlot(TimeResourceAllocation tra) {
		
		if (tra == null)
			return false;
		
		int slotsCount;
		if ((slotsCount = size()) < 1)
			return false;
		
		long startTimeLong = tra.getStart().getMillis();
		long endTimeLong = tra.getEnd().getMillis();
		float reqRes = 0;
		try {
			reqRes = tra.getAllocatedResource().getResourceUnit(ResourceParameterName.CPUCOUNT).getUsedAmount();
		} catch (NoSuchFieldException e1) {
			e1.printStackTrace();
		}
		
		TimeResourceAllocation slot;
		
		//find first slot
		int startSlot = 0; //TODO: binarySearch(startTimeLong);
		while ((slot = get(startSlot)).getEnd().getMillis() <= startTimeLong)
			startSlot++;
		
		//walk through slots and check
		for (int i = startSlot; i < slotsCount; i++) {
			
			float freeRes = 0;
			ResourceUnit resUnit = null;
			try {
				resUnit = slot.getAllocatedResource().getResourceUnit(ResourceParameterName.CPUCOUNT);
			} catch (NoSuchFieldException e) {
				e.printStackTrace();
			}
			freeRes = resUnit.getFreeAmount();
			
			if (reqRes > freeRes)
				return false;
					
			if (endTimeLong <= slot.getEnd().getMillis())
				return true;			

			slot = get(i);
		}
			
		return false;
	}
	
	/**
	 * Adds a slot
	 * @param tra a slot to be added (contains required amount of resources and time period)
	 *
	 * @author Ariel
	 */
	public void addSlot(TimeResourceAllocation tra) {

		if (tra == null)
			return;
		
		if (size() < 1)
			return;
		
		long startTimeLong = tra.getStart().getMillis();
		long endTimeLong = tra.getEnd().getMillis();
		
		TimeResourceAllocation slot;
		try {
			//find first slot
			int startSlot = 0;
			while ((slot = get(startSlot)).getEnd().getMillis() <= startTimeLong)
				startSlot++;
			
			//change of the first slot
			if (startTimeLong > slot.getStart().getMillis()) {
				
				if (endTimeLong > slot.getEnd().getMillis()) {
					ResourceStateDescription resState = new ResourceStateDescription(slot.getAllocatedResource());
					ResourceUnit ru = resState.getResourceUnit(ResourceParameterName.CPUCOUNT);
					ru.setUsedAmount(ru.getUsedAmount() + tra.getAllocatedResource().
																getResourceUnit(ResourceParameterName.CPUCOUNT).
																getUsedAmount());		
					TimeResourceAllocation newSlot = new TimeResourceAllocation(resState, tra.getStart(), slot.getEnd());
					add(startSlot++, newSlot);
				}
	
				slot.setEnd(tra.getStart());
			}
			
			//walk through slots and add
			while (endTimeLong > (slot = get(startSlot++)).getEnd().getMillis()) {
	
				ResourceUnit ru = slot.getAllocatedResource().getResourceUnit(ResourceParameterName.CPUCOUNT);
				ru.setUsedAmount(ru.getUsedAmount() + tra.getAllocatedResource().
															getResourceUnit(ResourceParameterName.CPUCOUNT).
															getUsedAmount());
				
			}
				
			//change of last slot
			
			if (endTimeLong < slot.getEnd().getMillis()) {
				ResourceStateDescription resState = new ResourceStateDescription(slot.getAllocatedResource());
				TimeResourceAllocation newSlot = new TimeResourceAllocation(resState, tra.getEnd(), slot.getEnd());
				add(startSlot, newSlot);
			}
			slot.setEnd(tra.getEnd());
			ResourceUnit ru = slot.getAllocatedResource().getResourceUnit(ResourceParameterName.CPUCOUNT);
			ru.setUsedAmount(ru.getUsedAmount() + tra.getAllocatedResource().
														getResourceUnit(ResourceParameterName.CPUCOUNT).
														getUsedAmount());
		} catch(NoSuchFieldException e){
			e.printStackTrace();
		}
		
	}

}