/*
 * 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.uima.internal.util;

import java.util.Locale;
import java.util.ResourceBundle;

import org.apache.uima.InternationalizedException;
import org.apache.uima.InternationalizedRuntimeException;

/**
 * Common implementation of InternationalizedException and InternationalizedRuntimeException
 */
public class I18nx_impl {

  /**
   * The base name of the resource bundle in which the message for this exception is located.
   */
  private String mResourceBundleName;

  /**
   * An identifier that maps to the message for this exception.
   */
  private String mMessageKey;

  /**
   * The arguments to this exception's message, if any. This allows an
   * <code>InternationalizedException</code> to have a compound message, made up of multiple parts
   * that are concatenated in a language-neutral way.
   */
  private Object[] mArguments;

  /**
   * The exception that caused this exception to occur.
   */
  private Throwable mCause;

  /**
   * the thread local class loader at creation time, see UIMA-4793 Transient to allow exceptions to
   * be serialized. Deserialized versions have null as their value, which is handled by the users
   */
  final transient private ClassLoader originalContextClassLoader;

  // see https://issues.apache.org/jira/browse/UIMA-5961
  // the resourceBundle associated with the default locale, at the time of creation of this instance
  final transient private ResourceBundle default_localized_resourceBundle;
  // the default locale, at the time of creation of this instance
  final transient private Locale default_locale;
  // a user specified resource bundle, used when the default_locale is not appropriate
  transient private ResourceBundle user_specified_resourceBundle = null;

  /**
   * Creates a new <code>InternationalizedException</code> with the specified message and cause.
   * 
   * @param aResourceBundleName
   *          the base name of the resource bundle in which the message for this exception is
   *          located.
   * @param aMessageKey
   *          an identifier that maps to the message for this exception. The message may contain
   *          placeholders for arguments as defined by the {@link java.text.MessageFormat
   *          MessageFormat} class.
   * @param aArguments
   *          The arguments to the message. <code>null</code> may be used if the message has no
   *          arguments.
   * @param aCause
   *          the original exception that caused this exception to be thrown, if any
   */
  public I18nx_impl(String aResourceBundleName, String aMessageKey, Object[] aArguments,
          Throwable aCause) {
    originalContextClassLoader = Thread.currentThread().getContextClassLoader();
    try {
      I18nUtil.setTccl(originalContextClassLoader);
      default_locale = Locale.getDefault();
      default_localized_resourceBundle = (aMessageKey == null) ? null
              : I18nUtil.resolveResourceBundle(aResourceBundleName, default_locale, null);
    } finally {
      I18nUtil.removeTccl();
    }
    mCause = aCause;
    mResourceBundleName = aResourceBundleName;
    mMessageKey = aMessageKey;
    mArguments = aArguments;
    // if null message and mCause is Internationalized exception, "promote" message
    if (mResourceBundleName == null && mMessageKey == null) {
      if (mCause instanceof InternationalizedException) {
        mResourceBundleName = ((InternationalizedException) mCause).getResourceBundleName();
        mMessageKey = ((InternationalizedException) mCause).getMessageKey();
        mArguments = ((InternationalizedException) mCause).getArguments();
      } else if (mCause instanceof InternationalizedRuntimeException) {
        mResourceBundleName = ((InternationalizedRuntimeException) mCause).getResourceBundleName();
        mMessageKey = ((InternationalizedRuntimeException) mCause).getMessageKey();
        mArguments = ((InternationalizedRuntimeException) mCause).getArguments();
      }
    }
  }

  /**
   * Gets the base name of the resource bundle in which the message for this exception is located.
   * 
   * @return the resource bundle base name. May return <code>null</code> if this exception has no
   *         message.
   */
  public String getResourceBundleName() {
    return mResourceBundleName;
  }

  /**
   * Gets the identifier for this exception's message. This identifier can be looked up in this
   * exception's {@link java.util.ResourceBundle ResourceBundle} to get the locale-specific message
   * for this exception.
   * 
   * @return the resource identifier for this exception's message. May return <code>null</code> if
   *         this exception has no message.
   */
  public String getMessageKey() {
    return mMessageKey;
  }

  /**
   * Gets the arguments to this exception's message. Arguments allow a
   * <code>InternationalizedException</code> to have a compound message, made up of multiple parts
   * that are concatenated in a language-neutral way.
   * 
   * @return the arguments to this exception's message.
   */
  public Object[] getArguments() {
    if (mArguments == null)
      return new Object[0];

    Object[] result = new Object[mArguments.length];
    System.arraycopy(mArguments, 0, result, 0, mArguments.length);
    return result;
  }

  /**
   * Gets the <i>English</i> detail message for this exception. For the localized message use
   * {@link #getLocalizedMessage()}.
   * 
   * @return the English detail message for this exception.
   */
  public String getMessage() {
    return getLocalizedMessage(Locale.ENGLISH);
  }

  /**
   * Gets the localized detail message for this exception. This uses the default Locale for this
   * JVM. A Locale may be specified using {@link #getLocalizedMessage(Locale)}.
   * 
   * @return this exception's detail message, localized for the default Locale.
   */
  public String getLocalizedMessage() {
    return getLocalizedMessage(Locale.getDefault());
  }

  /**
   * Gets the localized detail message for this exception using the specified <code>Locale</code>.
   * 
   * @param aLocale
   *          the locale to use for localizing the message
   * 
   * @return this exception's detail message, localized for the specified <code>Locale</code>.
   */
  public String getLocalizedMessage(Locale aLocale) {
    // check for null message
    if (getMessageKey() == null) {
      return null;
    }

    if (default_localized_resourceBundle != null && aLocale == default_locale) {
      return I18nUtil.localizeMessage(default_localized_resourceBundle, aLocale, getMessageKey(),
              getArguments());
    }

    if (user_specified_resourceBundle != null) {
      return I18nUtil.localizeMessage(user_specified_resourceBundle, aLocale, getMessageKey(),
              getArguments());
    }

    try {
      I18nUtil.setTccl(originalContextClassLoader);
      return I18nUtil.localizeMessage(getResourceBundleName(), aLocale, getMessageKey(),
              getArguments());
    } finally {
      I18nUtil.removeTccl();
    }
    // try {
    // // locate the resource bundle for this exception's messages
    // // turn over the classloader of the current object explicitly, so that the
    // // message resolving also works for derived exception classes
    // ResourceBundle bundle = ResourceBundle.getBundle(
    // getResourceBundleName(), aLocale, this.getClass()
    // .getClassLoader());
    // // retrieve the message from the resource bundle
    // String message = bundle.getString(getMessageKey());
    // // if arguments exist, use MessageFormat to include them
    // if (getArguments().length > 0) {
    // MessageFormat fmt = new MessageFormat(message);
    // fmt.setLocale(aLocale);
    // return fmt.format(getArguments());
    // } else
    // return message;
    // } catch (Exception e) {
    // return "EXCEPTION MESSAGE LOCALIZATION FAILED: " + e.toString();
    // }
  }

  /**
   * Gets the cause of this Exception.
   * 
   * @return the Throwable that caused this Exception to occur, if any. Returns <code>null</code> if
   *         there is no such cause.
   */
  public Throwable getCause() {
    return mCause;
  }

  public void setCause(Throwable cause) {
    mCause = cause;
  }

  /**
   * Checks if this exception, or any of its root causes, has a particular UIMA message key. This
   * allows checking for particular error condition
   * 
   * @param messageKey
   *          to search for in the exception chain
   * @return true if this exception or any of its root causes has a particular UIMA message key.
   */
  public boolean hasMessageKey(String messageKey) {
    if (messageKey.equals(getMessageKey())) {
      return true;
    }
    Throwable cause = getCause();
    if (cause != null && cause instanceof InternationalizedException) {
      return ((InternationalizedException) cause).hasMessageKey(messageKey);
    }
    return false;
  }

  /**
   * For the case where the default locale is not being used for getting messages, and the lookup
   * path in the classpath for the resource bundle needs to be set at a specific point, call this
   * method to set the resource bundle at that point in the call stack.
   * 
   * Example: If in a Pear, and you are throwing an exception, which is defined in a bundle in the
   * Pear context, but the catcher of the throw is up the stack above where the pear context exists
   * (and therefore, is no longer present at "catch" time), and you don't want to use the
   * default-locale for getting the message out of the message bundle,
   * 
   * then do something like this Exception e = new AnalysisEngineProcessException(MESSAGE_BUNDLE,
   * "TEST_KEY", objects); e.setResourceBundle(my_locale); // call this method, pass in the needed
   * locale object throw e; // or whatever should be done with it
   * 
   * @param aLocale
   *          the locale to use when getting the message from the message bundle at a later time
   */
  public void setResourceBundle(Locale aLocale) {
    user_specified_resourceBundle = I18nUtil.resolveResourceBundle(mResourceBundleName, aLocale,
            null);
  }
}
