/*
    * Copyright (c) 2002-2026 Gargoyle Software Inc.
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    * https://www.apache.org/licenses/LICENSE-2.0
    *
    * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.htmlunit.javascript.host.draganddrop;
  
  import org.htmlunit.WebWindow;
  import org.htmlunit.corejs.javascript.Callable;
  import org.htmlunit.corejs.javascript.Context;
  import org.htmlunit.javascript.AbstractJavaScriptEngine;
  import org.htmlunit.javascript.HtmlUnitScriptable;
  import org.htmlunit.javascript.JavaScriptEngine;
  import org.htmlunit.javascript.PostponedAction;
  import org.htmlunit.javascript.configuration.JsxClass;
  import org.htmlunit.javascript.configuration.JsxConstructor;
  import org.htmlunit.javascript.configuration.JsxFunction;
  import org.htmlunit.javascript.configuration.JsxGetter;
  import org.htmlunit.javascript.host.file.File;
  
  /**
   * A JavaScript object for {@code DataTransferItem}.
   *
   * @author Ahmed Ashour
   * @author Ronald Brill
   */
  @JsxClass
  public class DataTransferItem extends HtmlUnitScriptable {
  
      private static final String KIND_STRING = "string";
      private static final String KIND_FILE = "file";
  
      private final String kind_;
      private final String type_;
      private final Object data_;
  
      /**
       * Ctor.
       */
      public DataTransferItem() {
          this(null, null, null);
      }
  
      /**
       * Creates an instance.
       */
      private DataTransferItem(final String kind, final String type, final Object data) {
          super();
  
          kind_ = kind;
          type_ = type;
          data_ = data;
      }
  
      /**
       * Creates a string data transfer item.
       *
       * @param data the data
       * @param type the type
       * @return a new {@link DataTransferItem}
       */
      public static DataTransferItem buildStringItem(final CharSequence data, final String type) {
          return new DataTransferItem(KIND_STRING, type, data);
      }
  
      /**
       * Creates a file data transfer item.
       *
       * @param file the file
       * @return a new {@link DataTransferItem}
       */
      public static DataTransferItem buildFileItem(final File file) {
          return new DataTransferItem(KIND_FILE, file.getType(), file);
      }
  
      /**
       * JavaScript constructor.
       */
      @JsxConstructor
      public void jsConstructor() {
          // nothing to do
      }
  
      /**
       * Returns the {@code type} property.
       *
       * @return the {@code type} property
       */
      @JsxGetter
      public String getKind() {
         return kind_;
     }
 
     /**
      * Returns the {@code type} property.
      *
      * @return the {@code type} property
      */
     @JsxGetter
     public String getType() {
         return type_;
     }
 
     /**
      * Invokes the given callback with the drag data item's string data if the item contains a plain Unicode string.
      *
      * @param callback Function to execute
      */
     @JsxFunction
     public void getAsString(final Object callback) {
         if (!(callback instanceof Callable fun)) {
             throw JavaScriptEngine.typeError(
                     "getAsString callback '" + JavaScriptEngine.toString(callback) + "' is not a function");
         }
 
         if (isFile()) {
             return;
         }
 
         final Object[] args = {data_};
 
         final WebWindow webWindow = getWindow().getWebWindow();
         final PostponedAction action = new PostponedAction(webWindow.getEnclosedPage(), "getAsString callback") {
             @Override
             public void execute() {
                 fun.call(Context.getCurrentContext(), getParentScope(), DataTransferItem.this, args);
             }
         };
 
         final AbstractJavaScriptEngine<?> engine = webWindow.getWebClient().getJavaScriptEngine();
         engine.addPostponedAction(action);
     }
 
     /**
      * Returns the file represented by this drag data item.
      *
      * @return the drag data item's {@link File}, or {@code null} if this item is not a file
      */
     @JsxFunction
     public File getAsFile() {
         if (!isFile()) {
             return null;
         }
 
         return (File) data_;
     }
 
     /**
      * Returns whether this item represents a file.
      *
      * @return {@code true} if this item represents a file
      */
     public boolean isFile() {
         return kind_ == KIND_FILE;
     }
 }