/*
    * 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
    *
   *   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.apache.commons.compress.archivers.zip;
  
  import java.lang.reflect.Constructor;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Objects;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.concurrent.ConcurrentMap;
  import java.util.function.Supplier;
  import java.util.zip.ZipException;
  
  /**
   * {@link ZipExtraField} related methods.
   */
  // CheckStyle:HideUtilityClassConstructorCheck OFF (bc)
  public class ExtraFieldUtils {
  
      /**
       * "enum" for the possible actions to take if the extra field cannot be parsed.
       * <p>
       * This class has been created long before Java 5 and would have been a real enum ever since.
       * </p>
       *
       * @since 1.1
       */
      public static final class UnparseableExtraField implements UnparseableExtraFieldBehavior {
  
          /**
           * Key for "throw an exception" action.
           */
          public static final int THROW_KEY = 0;
          /**
           * Key for "skip" action.
           */
          public static final int SKIP_KEY = 1;
          /**
           * Key for "read" action.
           */
          public static final int READ_KEY = 2;
  
          /**
           * Throw an exception if field cannot be parsed.
           */
          public static final UnparseableExtraField THROW = new UnparseableExtraField(THROW_KEY);
  
          /**
           * Skip the extra field entirely and don't make its data available - effectively removing the extra field data.
           */
          public static final UnparseableExtraField SKIP = new UnparseableExtraField(SKIP_KEY);
  
          /**
           * Reads the extra field data into an instance of {@link UnparseableExtraFieldData UnparseableExtraFieldData}.
           */
          public static final UnparseableExtraField READ = new UnparseableExtraField(READ_KEY);
  
          private final int key;
  
          private UnparseableExtraField(final int k) {
              key = k;
          }
  
          /**
           * Key of the action to take.
           *
           * @return the key
           */
          public int getKey() {
              return key;
          }
  
          @Override
          public ZipExtraField onUnparseableExtraField(final byte[] data, final int off, final int len, final boolean local, final int claimedLength)
                  throws ZipException {
              switch (key) {
              case THROW_KEY:
                  throw new ZipException("Bad extra field starting at " + off + ".  Block length of " + claimedLength + " bytes exceeds remaining data of "
                          + (len - WORD) + " bytes.");
              case READ_KEY:
                  final UnparseableExtraFieldData field = new UnparseableExtraFieldData();
                  if (local) {
                      field.parseFromLocalFileData(data, off, len);
                 } else {
                     field.parseFromCentralDirectoryData(data, off, len);
                 }
                 return field;
             case SKIP_KEY:
                 return null;
             default:
                 throw new ZipException("Unknown UnparseableExtraField key: " + key);
             }
         }
 
     }
 
     private static final int WORD = 4;
 
     /**
      * Static registry of known extra fields.
      */
     private static final ConcurrentMap<ZipShort, Supplier<ZipExtraField>> IMPLEMENTATIONS;
 
     static {
         IMPLEMENTATIONS = new ConcurrentHashMap<>();
         IMPLEMENTATIONS.put(AsiExtraField.HEADER_ID, AsiExtraField::new);
         IMPLEMENTATIONS.put(X5455_ExtendedTimestamp.HEADER_ID, X5455_ExtendedTimestamp::new);
         IMPLEMENTATIONS.put(X7875_NewUnix.HEADER_ID, X7875_NewUnix::new);
         IMPLEMENTATIONS.put(JarMarker.ID, JarMarker::new);
         IMPLEMENTATIONS.put(UnicodePathExtraField.UPATH_ID, UnicodePathExtraField::new);
         IMPLEMENTATIONS.put(UnicodeCommentExtraField.UCOM_ID, UnicodeCommentExtraField::new);
         IMPLEMENTATIONS.put(Zip64ExtendedInformationExtraField.HEADER_ID, Zip64ExtendedInformationExtraField::new);
         IMPLEMENTATIONS.put(X000A_NTFS.HEADER_ID, X000A_NTFS::new);
         IMPLEMENTATIONS.put(X0014_X509Certificates.HEADER_ID, X0014_X509Certificates::new);
         IMPLEMENTATIONS.put(X0015_CertificateIdForFile.HEADER_ID, X0015_CertificateIdForFile::new);
         IMPLEMENTATIONS.put(X0016_CertificateIdForCentralDirectory.HEADER_ID, X0016_CertificateIdForCentralDirectory::new);
         IMPLEMENTATIONS.put(X0017_StrongEncryptionHeader.HEADER_ID, X0017_StrongEncryptionHeader::new);
         IMPLEMENTATIONS.put(X0019_EncryptionRecipientCertificateList.HEADER_ID, X0019_EncryptionRecipientCertificateList::new);
         IMPLEMENTATIONS.put(ResourceAlignmentExtraField.ID, ResourceAlignmentExtraField::new);
     }
 
     static final ZipExtraField[] EMPTY_ZIP_EXTRA_FIELD_ARRAY = {};
 
     /**
      * Creates an instance of the appropriate ExtraField, falls back to {@link UnrecognizedExtraField UnrecognizedExtraField}.
      *
      * @param headerId the header identifier
      * @return an instance of the appropriate ExtraField
      */
     public static ZipExtraField createExtraField(final ZipShort headerId) {
         final ZipExtraField field = createExtraFieldNoDefault(headerId);
         if (field != null) {
             return field;
         }
         final UnrecognizedExtraField u = new UnrecognizedExtraField();
         u.setHeaderId(headerId);
         return u;
     }
 
     /**
      * Creates an instance of the appropriate {@link ZipExtraField}.
      *
      * @param headerId the header identifier
      * @return an instance of the appropriate {@link ZipExtraField} or null if the id is not supported
      * @since 1.19
      */
     public static ZipExtraField createExtraFieldNoDefault(final ZipShort headerId) {
         final Supplier<ZipExtraField> provider = IMPLEMENTATIONS.get(headerId);
         return provider != null ? provider.get() : null;
     }
 
     /**
      * Fills in the extra field data into the given instance.
      *
      * <p>
      * Calls {@link ZipExtraField#parseFromCentralDirectoryData} or {@link ZipExtraField#parseFromLocalFileData} internally and wraps any
      * {@link ArrayIndexOutOfBoundsException} thrown into a {@link ZipException}.
      * </p>
      *
      * @param ze    the extra field instance to fill
      * @param data  the array of extra field data
      * @param off   offset into data where this field's data starts
      * @param len   the length of this field's data
      * @param local whether the extra field data stems from the local file header. If this is false then the data is part if the central directory header extra
      *              data.
      * @return the filled field, will never be {@code null}
      * @throws ZipException if an error occurs
      * @since 1.19
      */
     public static ZipExtraField fillExtraField(final ZipExtraField ze, final byte[] data, final int off, final int len, final boolean local)
             throws ZipException {
         try {
             if (local) {
                 ze.parseFromLocalFileData(data, off, len);
             } else {
                 ze.parseFromCentralDirectoryData(data, off, len);
             }
             return ze;
         } catch (final ArrayIndexOutOfBoundsException e) {
             throw ZipUtil.newZipException("Failed to parse corrupt ZIP extra field of type " + Integer.toHexString(ze.getHeaderId().getValue()), e);
         }
     }
 
     /**
      * Merges the central directory fields of the given ZipExtraFields.
      *
      * @param data an array of ExtraFields
      * @return an array of bytes
      */
     public static byte[] mergeCentralDirectoryData(final ZipExtraField[] data) {
         final int dataLength = data.length;
         final boolean lastIsUnparseableHolder = dataLength > 0 && data[dataLength - 1] instanceof UnparseableExtraFieldData;
         final int regularExtraFieldCount = lastIsUnparseableHolder ? dataLength - 1 : dataLength;
 
         int sum = WORD * regularExtraFieldCount;
         for (final ZipExtraField element : data) {
             sum += element.getCentralDirectoryLength().getValue();
         }
         final byte[] result = new byte[sum];
         int start = 0;
         for (int i = 0; i < regularExtraFieldCount; i++) {
             System.arraycopy(data[i].getHeaderId().getBytes(), 0, result, start, 2);
             System.arraycopy(data[i].getCentralDirectoryLength().getBytes(), 0, result, start + 2, 2);
             start += WORD;
             final byte[] central = data[i].getCentralDirectoryData();
             if (central != null) {
                 System.arraycopy(central, 0, result, start, central.length);
                 start += central.length;
             }
         }
         if (lastIsUnparseableHolder) {
             final byte[] central = data[dataLength - 1].getCentralDirectoryData();
             if (central != null) {
                 System.arraycopy(central, 0, result, start, central.length);
             }
         }
         return result;
     }
 
     /**
      * Merges the local file data fields of the given ZipExtraFields.
      *
      * @param data an array of ExtraFiles
      * @return an array of bytes
      */
     public static byte[] mergeLocalFileDataData(final ZipExtraField[] data) {
         final int dataLength = data.length;
         final boolean lastIsUnparseableHolder = dataLength > 0 && data[dataLength - 1] instanceof UnparseableExtraFieldData;
         final int regularExtraFieldCount = lastIsUnparseableHolder ? dataLength - 1 : dataLength;
 
         int sum = WORD * regularExtraFieldCount;
         for (final ZipExtraField element : data) {
             sum += element.getLocalFileDataLength().getValue();
         }
 
         final byte[] result = new byte[sum];
         int start = 0;
         for (int i = 0; i < regularExtraFieldCount; i++) {
             System.arraycopy(data[i].getHeaderId().getBytes(), 0, result, start, 2);
             System.arraycopy(data[i].getLocalFileDataLength().getBytes(), 0, result, start + 2, 2);
             start += WORD;
             final byte[] local = data[i].getLocalFileDataData();
             if (local != null) {
                 System.arraycopy(local, 0, result, start, local.length);
                 start += local.length;
             }
         }
         if (lastIsUnparseableHolder) {
             final byte[] local = data[dataLength - 1].getLocalFileDataData();
             if (local != null) {
                 System.arraycopy(local, 0, result, start, local.length);
             }
         }
         return result;
     }
 
     /**
      * Parses the array into ExtraFields and populate them with the given data as local file data, throwing an exception if the data cannot be parsed.
      *
      * @param data an array of bytes as it appears in local file data
      * @return an array of ExtraFields
      * @throws ZipException on error
      */
     public static ZipExtraField[] parse(final byte[] data) throws ZipException {
         return parse(data, true, UnparseableExtraField.THROW);
     }
 
     /**
      * Parses the array into ExtraFields and populate them with the given data, throwing an exception if the data cannot be parsed.
      *
      * @param data  an array of bytes
      * @param local whether data originates from the local file data or the central directory
      * @return an array of ExtraFields
      * @throws ZipException on error
      */
     public static ZipExtraField[] parse(final byte[] data, final boolean local) throws ZipException {
         return parse(data, local, UnparseableExtraField.THROW);
     }
 
     /**
      * Parses the array into ExtraFields and populate them with the given data.
      *
      * @param data            an array of bytes
      * @param parsingBehavior controls parsing of extra fields.
      * @param local           whether data originates from the local file data or the central directory
      * @return an array of ExtraFields
      * @throws ZipException on error
      * @since 1.19
      */
     public static ZipExtraField[] parse(final byte[] data, final boolean local, final ExtraFieldParsingBehavior parsingBehavior) throws ZipException {
         final List<ZipExtraField> v = new ArrayList<>();
         int start = 0;
         final int dataLength = data.length;
         LOOP: while (start <= dataLength - WORD) {
             final ZipShort headerId = new ZipShort(data, start);
             final int length = new ZipShort(data, start + 2).getValue();
             if (start + WORD + length > dataLength) {
                 final ZipExtraField field = parsingBehavior.onUnparseableExtraField(data, start, dataLength - start, local, length);
                 if (field != null) {
                     v.add(field);
                 }
                 // since we cannot parse the data we must assume
                 // the extra field consumes the whole rest of the
                 // available data
                 break LOOP;
             }
             try {
                 final ZipExtraField ze = Objects.requireNonNull(parsingBehavior.createExtraField(headerId), "createExtraField must not return null");
                 v.add(Objects.requireNonNull(parsingBehavior.fill(ze, data, start + WORD, length, local), "fill must not return null"));
                 start += length + WORD;
             } catch (final InstantiationException | IllegalAccessException e) {
                 throw ZipUtil.newZipException(e.getMessage(), e);
             }
         }
 
         return v.toArray(EMPTY_ZIP_EXTRA_FIELD_ARRAY);
     }
 
     /**
      * Parses the array into ExtraFields and populate them with the given data.
      *
      * @param data              an array of bytes
      * @param local             whether data originates from the local file data or the central directory
      * @param onUnparseableData what to do if the extra field data cannot be parsed.
      * @return an array of ExtraFields
      * @throws ZipException on error
      * @since 1.1
      */
     public static ZipExtraField[] parse(final byte[] data, final boolean local, final UnparseableExtraField onUnparseableData) throws ZipException {
         return parse(data, local, new ExtraFieldParsingBehavior() {
 
             @Override
             public ZipExtraField createExtraField(final ZipShort headerId) {
                 return ExtraFieldUtils.createExtraField(headerId);
             }
 
             @Override
             public ZipExtraField fill(final ZipExtraField field, final byte[] data, final int off, final int len, final boolean local) throws ZipException {
                 return fillExtraField(field, data, off, len, local);
             }
 
             @Override
             public ZipExtraField onUnparseableExtraField(final byte[] data, final int off, final int len, final boolean local, final int claimedLength)
                     throws ZipException {
                 return onUnparseableData.onUnparseableExtraField(data, off, len, local, claimedLength);
             }
         });
     }
 
     /**
      * Registers a ZipExtraField implementation, overriding a matching existing entry.
      * <p>
      * The given class must have a no-arg constructor and implement the {@link ZipExtraField ZipExtraField interface}.
      * </p>
      *
      * @param clazz the class to register.
      * @deprecated Use {@link ZipArchiveInputStream#setExtraFieldSupport} instead
      *             to not leak instances between archives and applications.
      */
     @Deprecated // note: when dropping update registration to move to a HashMap (static init)
     public static void register(final Class<?> clazz) {
         try {
             final Constructor<? extends ZipExtraField> constructor = clazz.asSubclass(ZipExtraField.class).getConstructor();
             final ZipExtraField zef = clazz.asSubclass(ZipExtraField.class).getConstructor().newInstance();
             IMPLEMENTATIONS.put(zef.getHeaderId(), () -> {
                 try {
                     return constructor.newInstance();
                 } catch (final ReflectiveOperationException e) {
                     throw new IllegalStateException(clazz.toString(), e);
                 }
             });
         } catch (final ReflectiveOperationException e) {
             throw new IllegalArgumentException(clazz.toString(), e);
         }
     }
 }