/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You 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
    *
    *      http://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.apache.commons.vfs2;
  
  import static org.junit.jupiter.api.Assertions.assertArrayEquals;
  
  import java.io.ByteArrayOutputStream;
  import java.io.InputStream;
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.net.URLConnection;
  import java.nio.charset.StandardCharsets;
  
  import junit.framework.TestCase;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.io.input.UnsynchronizedByteArrayInputStream;
  import org.apache.commons.vfs2.impl.DefaultFileSystemManager;
  import org.apache.commons.vfs2.provider.AbstractFileSystem;
  import org.apache.commons.vfs2.provider.local.DefaultLocalFileProvider;
  
  /**
   * File system test cases, which verifies the structure and naming functionality.
   * <p>
   * Works from a base folder, and assumes a particular structure under that base folder.
   * </p>
   * <p>
   * Not intended to be executed individually, but instead to be part of a {@link ProviderTestSuite}.
   * </p>
   */
  public abstract class AbstractProviderTestCase extends TestCase {
  
      // Expected contents of "file1.txt"
      public static final String FILE1_CONTENT = "This is a test file.";
      // Expected contents of test files
      public static final String TEST_FILE_CONTENT = "A test file.";
  
      private boolean addEmptyDir;
      private FileObject baseFolder;
      private DefaultFileSystemManager manager;
      private Method method;
      private ProviderTestConfig providerConfig;
      private FileObject readFolder;
      private FileObject writeFolder;
  
      protected void addEmptyDir(final boolean addEmptyDir) {
          this.addEmptyDir = addEmptyDir;
      }
  
      /**
       * Asserts that the content of a file is the same as expected. Checks the length reported by getSize() is correct,
       * then reads the content as a byte stream and compares the result with the expected content. Assumes files are
       * encoded using UTF-8.
       */
      protected void assertSameContent(final String expected, final FileObject fileObject) throws Exception {
          // Check the file exists, and is a file
          assertTrue(fileObject.exists());
          assertSame(FileType.FILE, fileObject.getType());
          assertTrue(fileObject.isFile());
          // Get file content as a binary stream
          final byte[] expectedBytes = expected.getBytes(StandardCharsets.UTF_8);
          // Check lengths
          final FileContent content = fileObject.getContent();
          assertEquals("same content length", expectedBytes.length, content.getSize());
          // Compare input streams
          try (InputStream in = content.getInputStream()) {
              assertTrue(IOUtils.contentEquals(UnsynchronizedByteArrayInputStream.builder().setByteArray(expectedBytes).get(), in));
          }
      }
  
      /**
       * Asserts that the content of a file is the same as expected. Checks the length reported by getContentLength() is
       * correct, then reads the content as a byte stream and compares the result with the expected content. Assumes files
       * are encoded using UTF-8.
       */
      protected void assertSameURLContent(final String expected, final URLConnection urlConnection) throws Exception {
          // Get file content as a binary stream
          final byte[] expectedBytes = expected.getBytes(StandardCharsets.UTF_8);
          // Check lengths
          assertEquals("same content length", expectedBytes.length, urlConnection.getContentLength());
          // Compare input streams
          try (InputStream in = urlConnection.getInputStream()) {
              assertTrue(IOUtils.contentEquals(UnsynchronizedByteArrayInputStream.builder().setByteArray(expectedBytes).get(), in));
          }
      }
 
     /**
      * Builds the expected structure of the read tests folder.
      *
      * @throws FileSystemException (possibly)
      */
     protected FileInfo buildExpectedStructure() throws FileSystemException {
         // Build the expected structure
         final FileInfo base = new FileInfo(getReadFolder().getName().getBaseName(), FileType.FOLDER);
         base.addFile("file1.txt", FILE1_CONTENT);
         // file%.txt - test out encoding
         base.addFile("file%25.txt", FILE1_CONTENT);
 
         // file?test.txt - test out encoding (test.txt is not the queryString)
         // as we do not know if the current file provider we need to
         // ask it to normalize the name
         // todo: move this into the FileInfo class to do it generally?
         /*
          * webdav-bug?: didn't manage to get the "?" correctly through webdavlib FileSystemManager fsm =
          * getReadFolder().getFileSystem().getFileSystemManager(); FileName fn =
          * fsm.resolveName(getReadFolder().getName(), "file%3ftest.txt"); String baseName = fn.getBaseName();
          * base.addFile(baseName, FILE1_CONTENT);
          */
         base.addFile("file space.txt", FILE1_CONTENT);
 
         base.addFile("empty.txt", "");
         if (addEmptyDir) {
             base.addFolder("emptydir");
         }
 
         final FileInfo dir = base.addFolder("dir1");
         dir.addFile("file1.txt", TEST_FILE_CONTENT);
         dir.addFile("file2.txt", TEST_FILE_CONTENT);
         dir.addFile("file3.txt", TEST_FILE_CONTENT);
 
         final FileInfo subdir1 = dir.addFolder("subdir1");
         subdir1.addFile("file1.txt", TEST_FILE_CONTENT);
         subdir1.addFile("file2.txt", TEST_FILE_CONTENT);
         subdir1.addFile("file3.txt", TEST_FILE_CONTENT);
 
         final FileInfo subdir2 = dir.addFolder("subdir2");
         subdir2.addFile("file1.txt", TEST_FILE_CONTENT);
         subdir2.addFile("file2.txt", TEST_FILE_CONTENT);
         subdir2.addFile("file3.txt", TEST_FILE_CONTENT);
 
         final FileInfo subdir3 = dir.addFolder("subdir3");
         subdir3.addFile("file1.txt", TEST_FILE_CONTENT);
         subdir3.addFile("file2.txt", TEST_FILE_CONTENT);
         subdir3.addFile("file3.txt", TEST_FILE_CONTENT);
 
         final FileInfo subdir4 = dir.addFolder("subdir4.jar");
         subdir4.addFile("file1.txt", TEST_FILE_CONTENT);
         subdir4.addFile("file2.txt", TEST_FILE_CONTENT);
         subdir4.addFile("file3.txt", TEST_FILE_CONTENT);
 
         return base;
     }
 
     /**
      * creates a new uninitialized file system manager
      *
      * @throws Exception
      */
     protected DefaultFileSystemManager createManager() throws Exception {
         final DefaultFileSystemManager fs = getProviderConfig().getDefaultFileSystemManager();
         fs.setFilesCache(getProviderConfig().getFilesCache());
         getProviderConfig().prepare(fs);
         if (!fs.hasProvider("file")) {
             fs.addProvider("file", new DefaultLocalFileProvider());
         }
         return fs;
     }
 
     /**
      * Returns the base test folder. This is the parent of both the read test and write test folders.
      */
     public FileObject getBaseFolder() {
         return baseFolder;
     }
 
     /**
      * some provider config do some post-initialization in getBaseTestFolder. This is a hack to allow access to this
      * code for {@code createManager}
      */
     public FileObject getBaseTestFolder(final FileSystemManager fs) throws Exception {
         return providerConfig.getBaseTestFolder(fs);
     }
 
     protected FileSystem getFileSystem() {
         final FileObject readFolder = getReadFolder();
         assertNotNull("This test's read folder should not be null", readFolder);
         return readFolder.getFileSystem();
     }
 
     /**
      * Gets the file system manager used by this test.
      */
     protected DefaultFileSystemManager getManager() {
         return manager;
     }
 
     /**
      * Gets the provider configuration.
      */
     public ProviderTestConfig getProviderConfig() {
         return providerConfig;
     }
 
     /**
      * Gets the read test folder.
      */
     protected FileObject getReadFolder() {
         return readFolder;
     }
 
     /**
      * Gets the capabilities required by the tests of this test case. The tests are not run if the provider being
      * tested does not support all the required capabilities. Return null or an empty array to always run the tests.
      * <p>
      * This implementation returns null.
      */
     protected Capability[] getRequiredCapabilities() {
         return null;
     }
 
     /**
      * Gets the write test folder.
      */
     protected FileObject getWriteFolder() {
         return writeFolder;
     }
 
     /**
      * Runs the test. This implementation short-circuits the test if the provider being tested does not have the
      * capabilities required by this test.
      * <p>
      * TODO - Handle negative caps as well: Only run a test if the provider does not have certain caps.
      * </p>
      * <p>
      * TODO - Figure out how to remove the test from the TestResult if the test is skipped.
      * </p>
      */
     @Override
     protected void runTest() throws Throwable {
         // Check the capabilities
         final Capability[] caps = getRequiredCapabilities();
         if (caps != null) {
             for (final Capability cap2 : caps) {
                 final Capability cap = cap2;
                 final FileSystem fs = getFileSystem();
                 if (!fs.hasCapability(cap)) {
                     // String name = fs.getClass().getName();
                     // int index = name.lastIndexOf('.');
                     // String fsName = (index > 0) ? name.substring(index + 1) : name;
                     // System.out.println("skipping " + getName() + " because " +
                     // fsName + " does not have capability " + cap);
                     return;
                 }
             }
         }
 
         // Provider has all the capabilities - execute the test
         if (method != null) {
             try {
                 method.invoke(this, (Object[]) null);
             } catch (final InvocationTargetException e) {
                 throw e.getTargetException();
             }
         } else {
             super.runTest();
         }
 
         if (readFolder != null && ((AbstractFileSystem) readFolder.getFileSystem()).isOpen()) {
             String name = "unknown";
             if (method != null) {
                 name = method.getName();
             }
 
             throw new IllegalStateException(getClass().getName() + ": filesystem has open streams after: " + name);
         }
     }
 
     /**
      * Configures this test.
      */
     public void setConfig(final DefaultFileSystemManager manager, final ProviderTestConfig providerConfig,
             final FileObject baseFolder, final FileObject readFolder, final FileObject writeFolder) {
         this.manager = manager;
         this.providerConfig = providerConfig;
         this.baseFolder = baseFolder;
         this.readFolder = readFolder;
         this.writeFolder = writeFolder;
         assertNotNull("setConfig manager", manager);
         assertNotNull("setConfig providerConfig", providerConfig);
         assertNotNull("setConfig baseFolder", baseFolder);
         assertNotNull("setConfig readFolder", readFolder);
         assertNotNull("setConfig writeFolder", writeFolder);
     }
 
     /**
      * Sets the test method.
      */
     public void setMethod(final Method method) {
         this.method = method;
     }
 
     /**
      * Sets the write test folder.
      *
      * @param folder
      */
     protected void setWriteFolder(final FileObject folder) {
         writeFolder = folder;
     }
 
     @Override
     public String toString() {
         return "AbstractProviderTestCase [baseFolder=" + baseFolder + ", readFolder=" + readFolder + ", writeFolder="
                 + writeFolder + ", manager=" + manager + ", providerConfig=" + providerConfig + ", method=" + method
                 + ", addEmptyDir=" + addEmptyDir + "]";
     }
 
 }