/*
    * SPDX-FileCopyrightText: Copyright (c) 2012-2025 Yegor Bugayenko
    * SPDX-License-Identifier: MIT
    */
   package com.jcabi.xml;
   
   import java.io.BufferedInputStream;
   import java.io.File;
   import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.URI;
  import java.net.URL;
  import java.nio.charset.StandardCharsets;
  import java.nio.file.Files;
  import java.util.Scanner;
  import lombok.EqualsAndHashCode;
  
  /**
   * Represent a given resource (InputStream, URL/URI location content, File)
   * as a string. UTF-8 encoding is used.
   *
   * <p>Objects of this class are immutable and thread-safe.
   *
   * @since 0.1
   */
  @EqualsAndHashCode(of = "content")
  final class TextResource {
  
      /**
       * The text representation.
       */
      private final transient String content;
  
      /**
       * Private constructor, used for initializing the field text content.
       * @param text The text content
       */
      private TextResource(final String text) {
          this.content = text;
      }
  
      /**
       * Public constructor, represent an InputStream as a text resource.
       *
       * <p>The provided input stream will be closed automatically after
       * getting data from it.
       * @param stream Stream to represent as text.
       */
      TextResource(final InputStream stream) {
          this(TextResource.readAsString(stream));
      }
  
      /**
       * Public constructor, represent a File as a text resource.
       * @param file File to represent as text.
       * @throws FileNotFoundException If file not found
       */
      TextResource(final File file) throws IOException {
          this(
              TextResource.readAsString(
                  new BufferedInputStream(Files.newInputStream(file.toPath()))
              )
          );
      }
  
      /**
       * Public constructor, represent a URL location as a text resource.
       * @param url URL to represent as text.
       * @throws IOException If an IO problem occurs.
       */
      TextResource(final URL url) throws IOException {
          this(TextResource.readAsString(url));
      }
  
      /**
       * Public constructor, represent a URI location as a text resource.
       * @param uri URI to represent as text.
       * @throws IOException If an IO problem occurs.
       */
      TextResource(final URI uri) throws IOException {
          this(TextResource.readAsString(uri.toURL()));
      }
  
      @Override
      public String toString() {
          return this.content;
      }
  
      /**
       * Reads an entire stream's contents into a string.
       * @param stream The stream to read
       * @return The stream content, in String form
       */
      private static String readAsString(final InputStream stream) {
          final String result;
          try (Scanner scanner = new Scanner(
              stream, StandardCharsets.UTF_8.name()
          ).useDelimiter("\\A")) {
             if (scanner.hasNext()) {
                 result = scanner.next();
             } else {
                 result = "";
             }
         }
         return result;
     }
 
     /**
      * Reads URI contents into a string.
      * @param url The URL to read
      * @return The stream content, in String form
      * @throws IOException if an IO exception occurs
      */
     private static String readAsString(final URL url) throws IOException {
         return TextResource.readAsString(
             new BufferedInputStream(url.openStream())
         );
     }
 }