package AWTBPEvents;

import java.util.*;
import java.awt.*;

/**
 * The Patient class is the source for Blood Pressure Events 
 * 
 * @author Stuart Hansen 
 * @version February 8, 2009
 */
public class Patient extends Component
{
	private static int SYSTOLIC_HIGH = 140;
	private static int SYSTOLIC_LOW = 90;
	
    // the vector of Blood Pressure Listeners
    // Note that we use Vector, rather than ArrayList, as Vectors are synchronized
    private Vector<BloodPressureListener> bpListeners; 
    
    private String name;          // the patient's name
    private int systolic;         // the patient's systolic blood pressure
    private int diastolic;        // the patient's diastolic blood pressure
    private int systolicTooHigh;  // the high level where an alarm sounds
    private int systolicTooLow;   // the low level where an alarm sounds
    
    private boolean warningFired; // keep track of whether a warning event
                                  // has recently fired.

    // the constructor
    public Patient (String name, int systolic, int diastolic)
    {
        bpListeners = new Vector<BloodPressureListener>();
        this.name = name;
        setSystolic(systolic);
        setDiastolic(diastolic);
        setSystolicWarningLevels(SYSTOLIC_HIGH, SYSTOLIC_LOW);
    }
  
    // Get the current systolic blood pressure
    public int getSystolic () {
        return systolic;
    }

    // Set the levels that will generate warnings
    public void setSystolicWarningLevels(int tooHigh, int tooLow)
    {
    	systolicTooHigh = tooHigh;
    	systolicTooLow = tooLow;
    }
    
    // set the current systolic blood pressure 
    public void setSystolic (int systolic) 
    {
    	int oldsystolic = this.systolic;
    	this.systolic = systolic;
    	
    	// Check to see if a warning event is warranted
    	if (!warningFired && 
    			(systolic >= systolicTooHigh 
    			|| systolic <= systolicTooLow))
    	{
    		warningFired = true;
    		fireBPEvent(new BloodPressureEvent(
    				       this, 
    				       BloodPressureEvent.WARNING_EVENT, 
    				       systolic));
    	}
    	else if (systolic < systolicTooHigh 
    			                && systolic > systolicTooLow)
    		warningFired = false;
    	
        // Check if an ordinary systolic change is warranted.
        if (oldsystolic != systolic) 
        {
            fireBPEvent(new BloodPressureEvent(
				          this, 
				          BloodPressureEvent.SYSTOLIC_EVENT, 
				          systolic));
        }
    }

    // get the Patient's name 
    public String getName()
    {
    	return name;
    }
    

    // get the current diastolic blood pressure 
    public int getDiastolic () {
        return diastolic;
    }

    // set the current diastolic blood pressure 
    public void setDiastolic (int diastolic) {
    	int olddiastolic = this.diastolic;
    	this.diastolic = diastolic;
        if (olddiastolic != diastolic) 
        {
            fireBPEvent(new BloodPressureEvent (
            		      this,
            		      BloodPressureEvent.DIASTOLIC_EVENT,
            		      diastolic));
        }
    }
    
    // Firing the event requires enqueuing it
    public void fireBPEvent (BloodPressureEvent e)
    {
    	Toolkit kit = java.awt.Toolkit.getDefaultToolkit();
    	EventQueue queue = kit.getSystemEventQueue();
    	queue.postEvent(e);
    }
            
    // Handle the blood pressure event when it comes out of the queue
    public void handleBPEvent (BloodPressureEvent e)
    {
        // clone the vector so registrations don't affect this event instance
        Vector<BloodPressureListener> temp = (Vector<BloodPressureListener>) bpListeners.clone();

        // Walk through the vector firing events to each listener
        Iterator<BloodPressureListener> bplIterator = temp.iterator();
        while (bplIterator.hasNext())
	    {
        	// The switch is needed to sort through the three types of
        	// blood pressure events
            BloodPressureListener bpl = bplIterator.next();
            switch (e.getID()){
            	case BloodPressureEvent.DIASTOLIC_EVENT:
                    bpl.diastolicChange(e);	
                    break;
            	case BloodPressureEvent.SYSTOLIC_EVENT:
            	    bpl.systolicChange(e);
            	    break;
            	case BloodPressureEvent.WARNING_EVENT:
            		bpl.warning(e);
            }
        }
    }

    // add a blood pressure listener to this patient
    public void addBloodPressureListener (BloodPressureListener bpListener)
    {
        bpListeners.add(bpListener);
    }

    // remove a blood pressure listener from this patient
    public void removeBloodPressureListener (BloodPressureListener bpListener)
    {
        bpListeners.remove(bpListener);
    }
}