package cmsc433.p2;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

/**
 * Validates a simulation
 */
public class Validate {
	private static class InvalidSimulationException extends Exception {
		public InvalidSimulationException() { }
	};

	// Helper method for validating the simulation
	private static void check(boolean check,
			String message) throws InvalidSimulationException {
		if (!check) {
			System.err.println("SIMULATION INVALID : "+message);
			throw new Validate.InvalidSimulationException();
		}
	}

	private static void printList(List l)
	{
		for(int i=0;i<l.size();i++)
			System.out.println(l.get(i));
	}
	
	private static int foodToInt(Food f)
	{
		if(f.name=="burger")
			return 0;
		if(f.name=="fries")
			return 1;
		if(f.name=="coke")
			return 2;
		return -1;
	}
	
	private static int machineToInt(Machine m)
	{
		if(m.name=="Grill")
			return 0;
		if(m.name=="Frier")
			return 1;
		if(m.name=="Soda Fountain")
			return 2;
		return -1;
	}
	
	/** 
	 * Validates the given list of events is a valid simulation.
	 * Returns true if the simulation is valid, false otherwise.
	 *
	 * @param events - a list of events generated by the simulation
	 *   in the order they were generated.
	 *
	 * @return whether the simulation was valid or not
	 */
	public static boolean validateSimulation(List<SimulationEvent> events) {
		try {
			check(events.get(0).event == SimulationEvent.EventType.SimulationStarting,
					"Simulation didn't start with initiation event");
			check(events.get(events.size()-1).event == 
					SimulationEvent.EventType.SimulationEnded,
					"Simulation didn't end with termination event");

			/* Write validation code for the following :
				Should not have more eaters than specified
				Should not have more cooks than specified
				The restaurant capacity should not be exceeded
				The capacity of each machine should not be exceeded
				Eater should not receive order until cook completes it
				Eater should not leave restaurant until order is received
				Eater should not place more than one order
				Cook should not work on order before it is placed
			 */

			Food burger = new Food("burger",500);
			Food fries = new Food("fries",250);
			Food coke = new Food("coke",100);
			
			int[] params = events.get(0).simParams;
			int numEaters = params[0];
			int numCooks = params[1];
			int numTables = params[2];
			int capacity = params[3];
			
			List<Food> defaultOrder = new ArrayList<Food>();
			defaultOrder.add(burger);
			defaultOrder.add(fries);
			defaultOrder.add(coke);
			
			Eater e;
			String en;
			List<Food> o;
			Integer on;
			Cook c;
			String cn;
			Food f;
			String fn;
			Machine m;
			int mid;

			int tableCount = 0;
			ArrayList<String> eaterList = new ArrayList<String>();
			ArrayList<String> eaterStarted = new ArrayList<String>();
			ArrayList<String> eaterEntered = new ArrayList<String>();
			ArrayList<String> eaterPlaced = new ArrayList<String>();
			ArrayList<String> eaterReceived = new ArrayList<String>();
			ArrayList<String> eaterLeft = new ArrayList<String>();
			
			ArrayList<Integer> orderList = new ArrayList<Integer>();
			ArrayList<Integer> orderWaiting = new ArrayList<Integer>();
			ArrayList<Integer> orderFinished = new ArrayList<Integer>();
			
			ArrayList<String> cookList = new ArrayList<String>();
			ArrayList<String> cookReady = new ArrayList<String>();
			HashMap<String,Integer> cookWithOrder = new HashMap<String,Integer>();
			HashMap<String,List<String>> cookFoodWaiting = new HashMap<String,List<String>>();
			HashMap<String,List<String>> cookFoodFinished = new HashMap<String,List<String>>();
			
			int[] foodToCook = new int[3];
			int[] foodToTake = new int[3];
			
			int[] machineReady = new int[3];
			int[] machineCooking = new int[3];
			
			for(int i=1;i<events.size()-1;i++)
			{
				SimulationEvent ei = events.get(i);
				
				switch(ei.event)
				{
				/* Eater events */
				case EaterStarting:
					e = ei.eater;
					check(e!=null,"Null Eater");
					en = e.toString();
					check(!eaterList.contains(en),"Duplicate Eater");
					eaterList.add(en);
					eaterStarted.add(en);
					break;
				case EaterEnteredRestaurant:
					e = ei.eater;
					check(e!=null,"Null Eater");
					en = e.toString();
					check(eaterStarted.contains(en),en+" entered before starting");
					eaterStarted.remove(en);
					eaterEntered.add(en);
					tableCount++;
					check(tableCount<=numTables,"Tables exceeded capacity");
					break;
				case EaterPlacedOrder:
					e = ei.eater;
					check(e!=null,"Null Eater");
					en = e.toString();
					check(eaterEntered.contains(en),en+" placed order before entering");
					eaterEntered.remove(en);
					eaterPlaced.add(en);
					//place order
					o = ei.orderFood;
					check(o!=null,"Null Order");
					on = ei.orderNumber;
					check(!orderList.contains(on),"Duplicate order number");
					orderList.add(on);
					orderWaiting.add(on);
					break;
				case EaterReceivedOrder:
					e = ei.eater;
					check(e!=null,"Null Eater");
					en = e.toString();
					check(eaterPlaced.contains(en),en+" received order before placing");
					eaterPlaced.remove(en);
					eaterReceived.add(en);
					//take order
					o = ei.orderFood;
					check(o!=null,"Null Order");
					on = ei.orderNumber;
					check(orderFinished.contains(on),en+" receiving order before finished");
					orderFinished.remove(on);
					break;
				case EaterLeavingRestaurant:
					e = ei.eater;
					check(e!=null,"Null Eater");
					en = e.toString();
					check(eaterReceived.contains(en),en+" leaving before receiving order");
					eaterReceived.remove(en);
					eaterLeft.add(en);
					tableCount--;
					break;
				/* Cook Events */
				case CookStarting:
					c = ei.cook;
					check(c!=null,"Null Cook");
					cn = c.toString();
					check(!cookList.contains(cn),"Duplicate Cook");
					cookList.add(cn);
					cookReady.add(cn);
					break;
				case CookReceivedOrder:
					c = ei.cook;
					check(c!=null,"Null Cook");
					cn = c.toString();
					check(cookReady.contains(cn),cn+" receiving order when not ready");
					cookReady.remove(cn);
					//check order
					o = ei.orderFood;
					check(o!=null,"Null Order");
					on = ei.orderNumber;
					check(orderWaiting.contains(on),on+" taken by cook before placed");
					orderWaiting.remove(on);
					cookWithOrder.put(cn, on);
					cookFoodWaiting.put(cn, new ArrayList<String>());
					cookFoodFinished.put(cn, new ArrayList<String>());
					for(Food fi : o)
						cookFoodWaiting.get(cn).add(fi.name);
					break;
				case CookStartedFood:
					c = ei.cook;
					check(c!=null,"Null Cook");
					cn = c.toString();
					on = ei.orderNumber;
					check(cookWithOrder.get(cn).equals(on),cn+" cooking food for wrong order");
					f = ei.food;
					fn = f.name;
					check(cookFoodWaiting.get(cn).contains(fn),cn+" cooking wrong food");
					cookFoodWaiting.get(cn).remove(fn);
					foodToCook[foodToInt(f)]++;
					break;
				case CookFinishedFood:
					c = ei.cook;
					check(c!=null,"Null Cook");
					cn = c.toString();
					on = ei.orderNumber;
					check(cookWithOrder.get(cn).equals(on),cn+" getting food for wrong order");
					f = ei.food;
					fn = f.name;
					check(foodToTake[foodToInt(f)]>0,cn+" getting food before finished");
					foodToTake[foodToInt(f)]--;
					cookFoodFinished.get(cn).add(fn);
					break;
				case CookCompletedOrder:
					c = ei.cook;
					check(c!=null,"Null Cook");
					cn = c.toString();
					on = ei.orderNumber;
					check(cookWithOrder.get(cn).equals(on),cn+" getting wrong order");
					check(cookFoodWaiting.get(cn).size()==0,cn+" didn't cook all foods");
					for(Food fd : defaultOrder)
						check(cookFoodFinished.get(cn).contains(fd.name),cn+" didn't cook enough foods");
					orderFinished.add(on);
					cookReady.add(cn);
					break;
				case CookEnding:
					c = ei.cook;
					check(c!=null,"Null Cook");
					cn = c.toString();
					check(cookReady.contains(cn),cn+" leaving while cooking");
					cookReady.remove(cn);
					break;
				/* Machine events */
				case MachineStarting:
					m = ei.machine;
					check(m!=null,"Null Machine");
					mid = machineToInt(m);
					check(machineReady[mid]==0,m.name+" invalid start");
					machineReady[mid]=1;
					break;
				case MachineStartingFood:
					m = ei.machine;
					check(m!=null,"Null Machine");
					mid = machineToInt(m);
					check(machineReady[mid]==1,m.name+" cooking food before starting");
					check(foodToCook[mid]>0,m.name+" no food to cook");
					foodToCook[mid]--;
					machineCooking[mid]++;
					check(machineCooking[mid]<=capacity,m.name+" exceeded capacity");
					break;
				case MachineDoneFood:
					m = ei.machine;
					check(m!=null,"Null Machine");
					mid = machineToInt(m);
					check(machineReady[mid]==1,m.name+" cooking food before starting");
					check(machineCooking[mid]>0,m.name+" no food to finish cooking");
					machineCooking[mid]--;
					foodToTake[mid]++;
					break;
				case MachineEnding:
					m = ei.machine;
					check(m!=null,"Null Machine");
					mid = machineToInt(m);
					check(machineReady[mid]==1,m.name+" ending before starting");
					machineReady[mid]=-1;
					break;
				default: 
				}
			}
			check(numEaters==eaterList.size(),"Incorrect number of eaters");
			check(numCooks==cookList.size(),"Incorrect number of cooks");
			check(eaterStarted.size()+eaterEntered.size()+eaterPlaced.size()+eaterReceived.size()==0,"Incompleted customers");
			check(cookReady.size()==0,"Cooks not sent home");
			check(machineReady[0]+machineReady[1]+machineReady[2]==-3,"Machines not ended");
			return true;
		} catch (InvalidSimulationException e) {
			return false;
		}
	}
}