package net.sourceforge.phpdt.internal.compiler.ast;

import net.sourceforge.phpdt.internal.compiler.ast.declarations.VariableUsage;

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

/**
 * A variable.
 * It could be a simple variable, or contains another variable.
 * @author Matthieu Casanova
 */
public class Variable extends AbstractVariable {

  /** The name of the variable. */
  private String name;

  /** A variable inside ($$varname). */
  private AbstractVariable variable;

  /**
   * Create a new simple variable.
   * @param name the name
   * @param sourceStart the starting position
   * @param sourceEnd the ending position
   */
  public Variable(final String name, final int sourceStart, final int sourceEnd) {
    super(sourceStart, sourceEnd);
    this.name = name;
  }

  /**
   * Create a special variable ($$toto for example).
   * @param variable the variable contained
   * @param sourceStart the starting position
   * @param sourceEnd the ending position
   */
  public Variable(final AbstractVariable variable, final int sourceStart, final int sourceEnd) {
    super(sourceStart, sourceEnd);
    this.variable = variable;
  }

  /**
   * Return the expression as String.
   * @return the expression
   */
  public String toStringExpression() {
    return "$" + getName();
  }

  public String getName() {
    if (variable == null) {
      return name;
    }
    return variable.toStringExpression();
  }

  /**
   * Get the variables from outside (parameters, globals ...)
   * @return the variables from outside
   */
  public List getOutsideVariable() {
    return new ArrayList(1);
  }

  /**
   * get the modified variables.
   * @return the variables modified
   */
  public List getModifiedVariable() {
    return new ArrayList(1);
  }

  /**
   * Get the variables used.
   * @return the variables used
   */
  public List getUsedVariable() {
    final ArrayList list = new ArrayList(1);
    if (name == null) {
      list.add(new VariableUsage(variable.getName(), getSourceStart()));
    } else {
      list.add(new VariableUsage(name, getSourceStart()));
    }
    return list;
  }
}