/* timeSelector.java
   Paul Carlisle
   
   This is a control panel which allows the user to set the time.
   Time is based, for display purposes, on a twelve-hour, AM/PM
   clock.

*/
import java.awt.*;
import java.util.*;
import java.lang.*;

public class timeSelector extends Panel
{
   // Time is stored as a fraction of a twenty-four hour day;
   // For example, 1:00 pm = 0.5416667
   private double currentTime;
   
   // Drop-down lists for the digits.
   private Choice hours, minutesHi, minutesLow;
   // ... and for AM/PM.
   private Choice AmPm;
   private GridBagLayout selectorLayout;
   private GridBagConstraints selectorConstraints;
   private int Width;
   private boolean gotMessage = false;
   

   public timeSelector(double time, Font inputFont,
					   Font checkFont, Font labelFont, int width)
   {
	  Width = width;
	  
	  setBackground(Color.lightGray);
	  
	  // Set layout formatting, color and font.
	  //selectorLayout = new GridLayout(1,0,0,0);
	  selectorLayout = new GridBagLayout();
	  selectorConstraints = new GridBagConstraints();
	  setLayout(selectorLayout);
	  
	  setBackground(Color.lightGray);
	  setFont(inputFont);
	  
	  // Instantiate the drop-down lists, and set their background
	  // color to white.
	  hours = new Choice();
	  hours.setBackground(Color.white);
	  
	  minutesHi = new Choice();
	  minutesHi.setBackground(Color.white);
	  
	  minutesLow = new Choice();
	  minutesLow.setBackground(Color.white);
	  
	  AmPm = new Choice();
	  AmPm.setBackground(Color.white);
	  
	  // Hours digits can be in range 1 through 12.
	  for (int i = 1; i <= 12; i++)
		 hours.addItem(new String(Integer.toString(i)) );
		 
	  // Hi digit of minutes can only be 0 through 5.
	  for (int i = 0; i <= 5; i++)
		 minutesHi.addItem(new String(Integer.toString(i)) );
		 
	  // Low digit of minutes can be 0 through 9.
	  for (int i = 0; i <= 9; i++)
		 minutesLow.addItem(new String(Integer.toString(i)) );
	  
	  // The AM/PM selector. 
	  AmPm.addItem("AM");
	  AmPm.addItem("PM");
	  
	  // Resize, and add to the panel.
	  resize(Width, 50);
	  
	  selectorConstraints.gridy = 0;
	  selectorConstraints.anchor = GridBagConstraints.CENTER;
	  selectorConstraints.fill = GridBagConstraints.BOTH;
	  
	  Panel pad = new Panel();
	  selectorConstraints.gridx = 0;
	  selectorLayout.setConstraints(pad,selectorConstraints);
	  add(pad);
	  
	  selectorConstraints.gridx = 1;
	  selectorLayout.setConstraints(hours,selectorConstraints);
	  add(hours);
	  
	  Label colon = new Label(":", Label.CENTER);
	  selectorConstraints.gridx = 2;
	  selectorConstraints.fill = GridBagConstraints.NONE;
	  selectorLayout.setConstraints(colon, selectorConstraints);
	  add(colon);
	  
	  selectorConstraints.gridx = 3;
	  selectorConstraints.fill = GridBagConstraints.BOTH;
	  selectorLayout.setConstraints(minutesHi,selectorConstraints);
	  add(minutesHi);
	  
	  selectorConstraints.gridx = 4;
	  selectorLayout.setConstraints(minutesLow,selectorConstraints);
	  add(minutesLow);
	  
	  selectorConstraints.gridx = 5;
	  selectorLayout.setConstraints(AmPm,selectorConstraints);
	  add(AmPm);
   
	  // Set the display to the selected year.
	  setTime(time);
   }   
   // Handles user manipulation of the display.
   public boolean action(Event e, Object what)
   {
	  double temp = currentTime;
	  
	  // If the user changed a digit...
	  if ( (e.target == hours) ||
		   (e.target == minutesHi)    ||
		   (e.target == minutesLow) ||
		   (e.target == AmPm) )
		   
	  {
		 // Read in all the digit settings, and form a new
		 // numeric time value from them.
		 
		 // Get numeric value of hour.   
		 double tempHours = hours.getSelectedIndex() + 1;
							
		 // Get numeric value of minute.
		 double tempMinutes = (double)(minutesHi.getSelectedIndex() * 10 + 
							   minutesLow.getSelectedIndex() ) / 60;
						  
							   
		 temp = tempHours + tempMinutes;
		 
		 
		 // Adjust for Am/Pm selection.
		 if ( (AmPm.getSelectedItem() == "PM") && (tempHours < 12) )
			temp = temp + 12;
		 else if ( (AmPm.getSelectedItem() == "AM") && (tempHours == 12) )
			temp = temp - 12;
			
		 temp = temp / 24;
		 
		 
	  }
	  
	  // Set the year, and reset the display.
	  setTime(temp);
	  
	  gotMessage = true;
	  
	  // Pass on all events.
	  return false;
   }   
   public boolean getMessage()
   {
	  boolean temp = gotMessage;
	  gotMessage = false;
	  return temp;
   }   
   // Returns the numeric value of the time displayed, as a fraction
   // of a twenty-four hour day. This will be a number between 0 and
   // not-quite-one.
   public double getTime()
   {
	  return currentTime;
   }   
   // Sets the display to reflect the time value.
   // WARNING! NO ERROR CHECKING!
   // Value submitted should be in range 0 <= time < 1.
	public void setTime(double time)
   {
	  // Set the digits to correspond to the passed value.
		 
	  // Forenoon. We treat Midnight as AM.
	  if (time < 0.5)
		 AmPm.select("AM");
	  else
		 AmPm.select("PM");
	  
	  // Calculate and set the value of the hour digits.
	  int tempHours = (int)(time * 24 + 1e-7);
	  
	  
	  if (tempHours > 12)
		 tempHours = tempHours - 12;
   
	  if (tempHours == 0)
		 hours.select(11);
	  else
		 hours.select(tempHours - 1);
	  
	  // Calculate and set the value of the minute digits.
	  double temp = (time * 24) - (int)(time * 24);
	  int tempMinutes = (int)Math.round(temp * 60) % 60;
	  
	  minutesHi.select(tempMinutes / 10);
	  minutesLow.select(tempMinutes % 10);
	  
	  currentTime = time;
   }   
   // Reduce flickering on redraws.
   public void update(Graphics g)
   {
	  paint(g);
   }   
}