////////////////////////////////////////////////////////////////////////////////
   // MillScript: an Open Spice interpreter and batch website creation tool
   // Copyright (C) 2001-2005 Open World Ltd
   // Copyright (C) 2005 Kevin Rogers
   //
   // This file is part of MillScript.
   //
   // MillScript is free software; you can redistribute it and/or modify it under
   // the terms of the GNU General Public License as published by the Free
  // Software Foundation; either version 2 of the License, or (at your option)
  // any later version.
  //
  // MillScript 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
  // MillScript; if not, write to the Free Software Foundation, Inc., 59 Temple
  // Place, Suite 330, Boston, MA  02111-1307  USA
  ////////////////////////////////////////////////////////////////////////////////
  package org.millscript.millscript.loaders;
  
  import org.millscript.commons.util.map.EHashMap;
  import org.millscript.commons.xml.api.Name;
  import org.millscript.commons.xml.api.token.EndTagToken;
  import org.millscript.commons.xml.api.token.StartTagToken;
  import org.millscript.commons.xml.tokenizer.NoNamespacesName;
  import org.millscript.millscript.expr.ConstantExpr;
  import org.millscript.millscript.expr.Expr;
  import org.millscript.millscript.expr.LambdaExpr;
  import org.millscript.millscript.expr.NameExpr;
  
  /**
   * This class implements the MillScript template loader. The specified file is
   * loaded as an XHTML file, but the additional elements <code>arg</code> and
   * <code>item</code> and attribute values starting with <code>?</code> take on
   * special meaning.
   */
  public final class TemplateLoader extends BasicXHTMLTemplateLoader {
  
      /**
       * A mapping from special element names to their handler.
       */
      private final EHashMap< Name, SpecialTemplateName > specialTemplateElements = new EHashMap< Name, SpecialTemplateName >();
  
      /**
       * Constructs a new XHTML template loader which does not support XML
       * namespaces, with the default set of special elements.
       */
      public TemplateLoader() {
          super( false );
          specialTemplateElements.insert(
              new NoNamespacesName( "item" ),
              new ItemName( this )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg" ),
              new ArgName( this )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg1" ),
              new ShortcutArgName( this, 1 )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg2" ),
              new ShortcutArgName( this, 2 )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg3" ),
              new ShortcutArgName( this, 3 )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg4" ),
              new ShortcutArgName( this, 4 )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg5" ),
              new ShortcutArgName( this, 5 )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg6" ),
              new ShortcutArgName( this, 6 )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg7" ),
              new ShortcutArgName( this, 7 )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg8" ),
              new ShortcutArgName( this, 8 )
          );
          specialTemplateElements.insert(
              new NoNamespacesName( "arg9" ),
              new ShortcutArgName( this, 9 )
          );
      }
  
      /**
      * @see org.millscript.millscript.loaders.BasicTemplateLoader#compAttributeValue(java.lang.String)
      */
     @Override
     public Expr compAttributeValue( final String value ) {
         if ( value.length() > 0 && value.charAt( 0 ) == '?' ) {
             // Compile everything but the leading '?'
             return compSpecialString( value.substring( 1, value.length() ) );
         } else {
             return new ConstantExpr( value );
         }
     }
 
     /**
      * @see org.millscript.millscript.loaders.BasicTemplateLoader#compileEndTag(org.millscript.commons.xml.api.token.EndTagToken)
      */
     @Override
     public void compileEndTag( final EndTagToken token ) {
         final SpecialTemplateName specialName = this.specialTemplateElements.get( token.getName() );
         if ( specialName == null ) {
             super.compileEndTag( token );
         } else {
             specialName.handle();
             // End this element
             this.tokenVisitor = this.tokenVisitor.parentTokenVisitor;
         }
     }
 
     /**
      * @see org.millscript.millscript.loaders.BasicTemplateLoader#compileStartTag(org.millscript.commons.xml.api.token.StartTagToken)
      */
     @Override
     public void compileStartTag( final StartTagToken token ) {
         if ( this.specialTemplateElements.containsKey( token.getName() ) ) {
             // ok, we allow these special elements through, just start another
             // normal element
             this.tokenVisitor = new BasicTemplateLoaderElementTokenVisitor( this, this.tokenVisitor, token );
         } else {
             super.compileStartTag( token );
         }
     }
 
     /**
      * @see org.millscript.millscript.loaders.BasicTemplateLoader#makeLambda(java.lang.String, org.millscript.millscript.expr.Expr)
      */
     @Override
     public Expr makeLambda( final String theName, final Expr body ) {
         return (
             new LambdaExpr(
                 theName,
                 null,
                 new NameExpr( "arg" ),
                 body
             )
         );
     }
 
 }