/*
 * CSP Project
 * Authors:
 * 		Jay Bernardo
 * 		Matt Rancourt
 * 
 * File: AbstractVariable.java
 * 
 * Contains the AbstractVariable class. This class is used to represent variables in the CSP
 * problem domain. In our impementation we have both the TransitionAssignmentVariable and regular
 * Variable
 * 
 *  See: TransitionAssignmentVariable.java
 *       Variable.java
 * 
 */
abstract class AbstractVariable{
	String name;
	int value;
	boolean positive;
	
	/**
	 * Basic constructor. Creates a variable with a given name
	 * and value
	 * @param name - name of the variable
	 * @param value - value assigned to the variable
	 */
	public AbstractVariable(String name, int value, boolean positive)
	throws
		InvalidVariableValueException{
		this.name = name;
		this.positive = positive;
		this.setValue(value);
	}
	
	/**
	 * Sets the value of the variable
	 * @param value - value to set the variable to
	 */
	public void setValue(int value)
	throws
		InvalidVariableValueException{
		if(value < -1 || value > 1)
			throw new InvalidVariableValueException();
		
		this.value = value;
	}
	
	/**
	 * Returns the value of the variable
	 * @return value of variable as an int
	 */
	public int getValue(){
		if(positive == false){
			if(value == 0)
				return 1;
			else if(value == 1)
				return 0;
			else
				return value;
		}
		
		return value;
	}

	/**
	 * Returns the name of the variable
	 * @return name of the variable as a String
	 */
	public String getName(){
		return name;
	}
	
	
	/**
	 * Sets whether this variable is a positive or not
	 * @param p - whether the variable is a positive or not
	 */
	public void setPositive(boolean p){
		positive = p;
	}
	
	/**
	 * Returns whether this variable is positive or
	 * negative
	 * @return true if positive, false otherwise
	 */
	public boolean getPositive(){
		return positive;
	}
	
	/** 
	 * Prints the variable in a "pretty" format
	 */
	public void print(){
		if(positive == false){
			System.out.print("!");
		}
		
		System.out.print(name);
		//System.out.print(name + "[" + value + "]");
	}
}