/*   SimpleExample/Main.java

Main -- Simple class to get program going.

In this case, it creates a few Ant instances, asks them to do a few things.
Note we use some Java classes -- ArrayList and Random

Compile:  javac Main.java Ant.java
Run:      java  Main  
Copy:     cp /users/rlr/Courses/530/Src/SimpleExample/*.java  yourDir

*/

import java.util.*;      // for misc java classes (eg ArrayList, Random)

public class Main {     

	public static void main ( String args[] ) { 
		Random	rng;                // address of a instance of Random 
	    int		numberOfAnts = 8;  	// create this many ants.
		Ant		anAnt, anAnt1; 		// variables to hold addresses of Ant instances

		// define an ArrayList object that can contain pointers to Ant objects
		// note we specify that this ArrayList can refer *only* to Ant objects
		ArrayList <Ant> antList = new ArrayList <Ant> ();

		rng = new Random();	 // create instance of Random -- see the Java API
		Ant.setRng( rng );   // tell the Ant class about the rng we created.

		// lets create a bunch of ants, adding them to the antList.
		System.out.printf( "\nCreate %d ants...", numberOfAnts );
		for ( int i = 0; i < numberOfAnts; ++i ) {
			anAnt = new Ant( i, i*2 , i * 4.2 );
			antList.add( anAnt );
		}
		
		// Now send the printSelf message to each Ant on the list.
		// get(i) returns the pointer to the i-th entry (NB: counts from zero!!)
		System.out.printf( "Created %d ants. They are:\n", antList.size() );
		for ( int i = 0; i < antList.size(); ++i ) {
			anAnt = antList.get( i );
			anAnt.printSelf();
		}

		// note we don't have to store the reference in a local variable:
		System.out.printf( "\nAgain the Ants are:\n", antList.size() );
		for ( int i = 0; i < antList.size(); ++i )
			(antList.get( i )).printSelf();

		// Lets send the ants another message, and print what each returns to us.
		System.out.printf( "\nSend doSomething() to the Ants, print return value:\n");
		for ( int i = 0; i < antList.size(); ++i ) {
			anAnt = antList.get( i );
			double d = anAnt.doSomething( i );
			System.out.printf( "   --- %.1f placed in variable d in Main.\n", d );
		}

		// remove ant by position in list (NB: counts from zero!!)
		int index = 3;
		anAnt = antList.remove( index );
		System.out.printf( "\nRemoved Ant from position (index) %d:\n", index );
		anAnt.printSelf();
		System.out.printf( "The list now:\n" );
		Main.printAntList( antList );

		// change its weight, then add it back by position
		anAnt.setWeight( 1000.0 );
		antList.add( index, anAnt );
		System.out.printf( "\nList after add Ant (wt=1000) back to pos=%d:\n",index );
		Main.printAntList( antList );

		// lets add it in again (to the end this time!)
		antList.add( anAnt );
		System.out.printf( "\nThe list after adding ant again to end:\n" );
		Main.printAntList( antList );

		// lets change the weight in the Ant that anAnt references.
		anAnt.setWeight( 20000 );
		System.out.printf( "\nThe list after setting weight of anAnt to 20000:\n" );
		Main.printAntList( antList );

		// lets remove it by reference -- removes the first occurence in the list!
		antList.remove( anAnt );
		System.out.printf( "\nThe list after removing it by reference:\n" );
		Main.printAntList( antList );

		// lets re-assign weights at random using the new java for-construct:
		for ( Ant a : antList )
			a.setWeight( rng.nextDouble() );

		System.out.printf( "\nThe list after randomizing weights:\n" );
		Main.printAntList( antList );

		// an example of a while-loop and if-else test
		System.out.printf( "\nThe list categorized:\n" );
		int i = 0;
		while ( i < antList.size() ) {
			Ant wAnt = antList.get(i);  // Tthese variables exist ONLY in this loop!!
			double lowerBd = 0.333, upperBd = 0.667;
			if ( wAnt.getWeight() < lowerBd ) {
				System.out.printf( "Ant %d wt = %.3f (wt < %.1f).\n", wAnt.getID(),
								   wAnt.getWeight(), lowerBd );
			}
			else if ( wAnt.getWeight() > upperBd ) {
				System.out.printf( "Ant %d wt = %.3f (wt > %.1f).\n", wAnt.getID(),
								   wAnt.getWeight(), upperBd );
			}
			else {
				System.out.printf( "Ant %d wt = %.3f (%.1f <= wt <= %.1f).\n", 
								   wAnt.getID(),
								   wAnt.getWeight(), lowerBd, upperBd );
			}
			++i;  // DON'T FORGET THIS!!
		}

		System.out.printf( "\nAll done!\n\n" );
	}

	// a (static) method to print the contents of an Ant list
	public static void printAntList ( ArrayList <Ant> list ) {
		for ( Ant a : list )                   // Note this kind of loop construct!
			System.out.printf( " ID = %d, weight = %.3f\n", 
							   a.getID(), a.getWeight() );
	}	

}