// ******************************************************************************
   //
   // Title:       Force Field X.
   // Description: Force Field X - Software for Molecular Biophysics.
   // Copyright:   Copyright (c) Michael J. Schnieders 2001-2024.
   //
   // This file is part of Force Field X.
   //
   // Force Field X is free software; you can redistribute it and/or modify it
  // under the terms of the GNU General Public License version 3 as published by
  // the Free Software Foundation.
  //
  // Force Field X is distributed in the hope that it will be useful, but WITHOUT
  // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  // FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
  // details.
  //
  // You should have received a copy of the GNU General Public License along with
  // Force Field X; if not, write to the Free Software Foundation, Inc., 59 Temple
  // Place, Suite 330, Boston, MA 02111-1307 USA
  //
  // Linking this library statically or dynamically with other modules is making a
  // combined work based on this library. Thus, the terms and conditions of the
  // GNU General Public License cover the whole combination.
  //
  // As a special exception, the copyright holders of this library give you
  // permission to link this library with independent modules to produce an
  // executable, regardless of the license terms of these independent modules, and
  // to copy and distribute the resulting executable under terms of your choice,
  // provided that you also meet, for each linked independent module, the terms
  // and conditions of the license of that module. An independent module is a
  // module which is not derived from or based on this library. If you modify this
  // library, you may extend this exception to your version of the library, but
  // you are not obligated to do so. If you do not wish to do so, delete this
  // exception statement from your version.
  //
  // ******************************************************************************
  package ffx.utilities;
  
  import org.apache.commons.configuration2.CompositeConfiguration;
  import java.util.LinkedHashMap;
  import java.util.Map;
  
  /**
   * This represents the context of an FFX MolecularAssembly.
   * <p>
   * CompositeConfiguration is extended by adding the API used by the Groovy Binding class.
   * <p>
   * The Binding API represents the variable bindings of a script which can be altered from outside the
   * script object or created and passed into it.
   * <p>
   * The Binding API is not supposed to be used in a multithreaded context.
   *
   * @author Michael J. Schnieders
   */
  public class FFXContext extends CompositeConfiguration {
  
    private Map<String, Object> variables;
  
    /**
     * <p>Constructor for FFXContext.</p>
     */
    public FFXContext() {
      super();
    }
  
    /**
     * <p>Constructor for FFXContext.</p>
     *
     * @param variables a {@link java.util.Map} object
     */
    public FFXContext(Map<String, Object> variables) {
      this();
      this.variables = variables;
    }
  
    /**
     * A helper constructor used in main(String[]) method calls
     *
     * @param args are the command line arguments from a main()
     */
    public FFXContext(String[] args) {
      this();
      variables = new LinkedHashMap<>();
      variables.put("args", args);
    }
  
    /**
     * <p>getVariable.</p>
     *
     * @param name the name of the variable to lookup
     * @return the variable value
     * @throws java.lang.Exception if any.
     */
    public Object getVariable(String name) throws Exception {
      if (variables == null) {
        throw new Exception(name);
      }
  
     Object result = variables.get(name);
 
     if (result == null && !variables.containsKey(name)) {
       throw new Exception(name);
     }
 
     return result;
   }
 
   /**
    * Sets the value of the given variable
    *
    * @param name the name of the variable to set
    * @param value the new value for the given variable
    */
   public void setVariable(String name, Object value) {
     if (variables == null) {
       variables = new LinkedHashMap<>();
     }
     variables.put(name, value);
   }
 
   /**
    * Remove the variable with the specified name.
    *
    * @param name the name of the variable to remove
    */
   public void removeVariable(String name) {
     if (null == variables) {
       return;
     }
 
     variables.remove(name);
   }
 
   /**
    * Simple check for whether the context contains a particular variable or not.
    *
    * @param name the name of the variable to check for
    * @return a boolean
    */
   public boolean hasVariable(String name) {
     return variables != null && variables.containsKey(name);
   }
 
   /**
    * Get the Map of all variables. This returns a reference and not a copy.
    *
    * @return a Map of the variables.
    */
   public Map<String, Object> getVariables() {
     if (variables == null) {
       variables = new LinkedHashMap<>();
     }
     return variables;
   }
 
   /**
    * Set the Map of all variables. The reference is kept without making a copy.
    *
    * @param variables a Map of the variables.
    */
   public void setVariables(Map<String, Object> variables) {
     this.variables = variables;
   }
 
 }