z80-tools/src/nl/grauw/glass/expressions/Expression.java

package nl.grauw.glass.expressions;

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

import nl.grauw.glass.instructions.InstructionFactory;

public abstract class Expression {
	
	public abstract String toDebugString();
	
	public abstract Expression copy(Context context);
	
	public Expression resolve() {
		return this;
	}
	
	public boolean isInteger() {
		return false;
	}
	
	public int getInteger() {
		throw new EvaluationException("Not an integer.");
	}
	
	public boolean isString() {
		return false;
	}
	
	public String getString() {
		throw new EvaluationException("Not a string.");
	}
	
	public boolean isRegister() {
		return false;
	}
	
	public Register getRegister() {
		throw new EvaluationException("Not a register.");
	}
	
	public boolean isFlag() {
		return false;
	}
	
	public Flag getFlag() {
		throw new EvaluationException("Not a flag.");
	}
	
	public boolean isGroup() {
		return false;
	}
	
	public Identifier getAnnotation() {
		return null;
	}
	
	public Expression getAnnotee() {
		return this;
	}
	
	public boolean isInstruction() {
		return false;
	}
	
	public InstructionFactory getInstruction() {
		throw new EvaluationException("Not an instruction.");
	}
	
	public boolean isContext() {
		return false;
	}
	
	public Context getContext() {
		throw new EvaluationException("Not a context.");
	}
	
	public boolean isSectionContext() {
		return false;
	}
	
	public SectionContext getSectionContext() {
		throw new EvaluationException("Not a context.");
	}
	
	public int getAddress() {
		return getInteger();
	}
	
	public List<Expression> getList() {
		List<Expression> list = new ArrayList<>();
		addToList(list);
		return list;
	}
	
	protected void addToList(List<Expression> list) {
		list.add(this);
	}
	
	public Expression getElement() {
		return getElement(0);
	}
	
	public Expression getElement(int index) {
		return index == 0 ? this : null;
	}
	
	public Expression getNext() {
		return null;
	}
	
	public String getHexValue() {
		String string = Integer.toHexString(getInteger()).toUpperCase();
		return (string.charAt(0) >= 'A' && string.charAt(0) <= 'F' ? "0" : "") + string + "H";
	}
	
}