MonoRail/Castle.MonoRail.Framework/Internal/JSGeneratorBase.cs

   1 // Copyright 2004-2007 Castle Project - http://www.castleproject.org/
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //     http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 namespace Castle.MonoRail.Framework.Internal
  16 {
  17         using System;
  18         using Castle.MonoRail.Framework.Helpers;
  19
  20         /// <summary>
  21         /// Abstract class that contains the shared logic of JS Generation, separated from
  22         /// the various view engines implementations
  23         /// </summary>
  24         public abstract class JSGeneratorBase
  25         {
  26                 /// <summary>
  27                 /// The generator instance
  28                 /// </summary>
  29                 protected readonly IJSGenerator generator;
  30
  31                 /// <summary>
  32                 /// Initializes a new instance of the <see cref="JSGeneratorBase"/> class.
  33                 /// </summary>
  34                 /// <param name="generator">The generator.</param>
  35                 protected JSGeneratorBase(IJSGenerator generator)
  36                 {
  37                         this.generator = generator;
  38                 }
  39
  40                 /// <summary>
  41                 /// Executes an operation (totally late bound)
  42                 /// </summary>
  43                 /// <param name="method">The method.</param>
  44                 /// <param name="args">The args.</param>
  45                 /// <returns></returns>
  46                 protected object InternalInvoke(string method, params object[] args)
  47                 {
  48                         if (method == "el")
  49                         {
  50                                 if (args == null || args.Length != 1)
  51                                 {
  52                                         throw new ArgumentException("el() method must be invoked with the element name as an argument");
  53                                 }
  54                                 if (args[0] == null)
  55                                 {
  56                                         throw new ArgumentNullException("el() method invoked with a null argument");
  57                                 }
  58
  59                                 return CreateJSElementGenerator(
  60                                         generator.CreateElementGenerator(args[0].ToString()));
  61                         }
  62                         else if (method == "select")
  63                         {
  64                                 if (args == null || args.Length != 1)
  65                                 {
  66                                         throw new ArgumentException(
  67                                                 "select() method must be invoked with the element/css selection rule name as an argument");
  68                                 }
  69                                 if (args[0] == null)
  70                                 {
  71                                         throw new ArgumentNullException("select() method invoked with a null argument");
  72                                 }
  73
  74                                 return CreateJSCollectionGenerator(
  75                                         generator.CreateCollectionGenerator(args[0].ToString()));
  76                         }
  77
  78                         DynamicDispatchSupport dispInterface = generator as DynamicDispatchSupport;
  79                         if (dispInterface == null)
  80                         {
  81                                 throw new MonoRail.Framework.RailsException("JS Generators must inherit DynamicDispatchSupport");
  82                         }
  83
  84                         if (dispInterface.IsGeneratorMethod(method))
  85                         {
  86                                 return dispInterface.Dispatch(method, args);
  87                         }
  88
  89                         return CreateNullGenerator();
  90                 }
  91
  92                 /// <summary>
  93                 /// Creates a null generator.
  94                 /// </summary>
  95                 /// <returns></returns>
  96                 protected abstract object CreateNullGenerator();
  97
  98                 /// <summary>
  99                 /// Creates a JS collection generator.
 100                 /// </summary>
 101                 /// <param name="collectionGenerator">The collection generator.</param>
 102                 /// <returns></returns>
 103                 protected abstract object CreateJSCollectionGenerator(IJSCollectionGenerator collectionGenerator);
 104
 105                 /// <summary>
 106                 /// Creates a JS element generator.
 107                 /// </summary>
 108                 /// <param name="elementGenerator">The element generator.</param>
 109                 /// <returns></returns>
 110                 protected abstract object CreateJSElementGenerator(IJSElementGenerator elementGenerator);
 111
 112                 /// <summary>
 113                 /// Delegates to the generator
 114                 /// </summary>
 115                 /// <returns>
 116                 /// A <see cref="T:System.String"></see> that represents the current <see cref="T:System.Object"></see>.
 117                 /// </returns>
 118                 public override string ToString()
 119                 {
 120                         return generator.ToString();
 121                 }
 122         }
 123 }