/*
 * Copyright 2018 A-SIT Plus GmbH
 * AT-specific eIDAS Connector has been developed in a cooperation between EGIZ,
 * A-SIT Plus GmbH, A-SIT, and Graz University of Technology.
 *
 * Licensed under the EUPL, Version 1.2 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "License");
 * You may not use this work except in compliance with the License.
 * You may obtain a copy of the License at:
 * https://joinup.ec.europa.eu/news/understanding-eupl-v12
 *
 * 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.
 *
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
*/

package at.asitplus.eidas.specific.connector.provider;

import java.text.MessageFormat;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.MessageSource;
import org.springframework.context.MessageSourceAware;
import org.springframework.context.NoSuchMessageException;
import org.springframework.context.i18n.LocaleContextHolder;
import org.springframework.stereotype.Service;

import at.gv.egiz.eaaf.core.api.IStatusMessenger;
import at.gv.egiz.eaaf.core.exceptions.EaafException;
import at.gv.egiz.eaaf.core.impl.logging.LogMessageProviderFactory;

@Service("StatusMessageProvider")
public class StatusMessageProvider implements IStatusMessenger, MessageSourceAware {
  private static final Logger log = LoggerFactory.getLogger(StatusMessageProvider.class);

  private static final String ERROR_MESSAGES_UNAVAILABLE =
      "Error messages can NOT be load from application. Only errorCode: {0} is availabe";
  private static final String ERROR_NO_MESSAGE = "No errormesseage for error with number.={0}";

  private static final String ERROR_EXTERNALERROR_CODES_UNAVAILABLE =
      "External error-codes can NOT be load from application. Only internal errorCode: {0} is availabe";
  private static final String ERROR_NO_EXTERNALERROR_CODE =
      "No external error for internal error with number.={0}";
  private static final String MSG_WARN_NO_SOURCE = "MessageCode: {} is NOT SET for locale: {}";
  private static final String MSG_INFO = "Use locale: {} as default";
  
  // external error codes
  private static final String DEFAULT_EXTERNALERROR_RESOURCES = "properties/external_statuscodes_map";
  private static final Locale DEFAULT_EXTERNALERROR_LOCALES = new Locale("en", "GB");
  private ResourceBundle externalError = null;

  //internal messanges
  private MessageSource messageSource;

  @Override
  public String getMessageWithoutDefault(final String messageId, final Object[] parameters) {
    if (messageSource == null) {
      return null;

    } else {
      try {
        final Locale locale = LocaleContextHolder.getLocale();
        return messageSource.getMessage(messageId, parameters, locale);

      } catch (final NoSuchMessageException e) {
        log.info(MSG_WARN_NO_SOURCE, messageId, LocaleContextHolder.getLocale());
        log.debug(MSG_INFO, Locale.ENGLISH);

        try {
          return messageSource.getMessage(messageId, parameters, Locale.ENGLISH);

        } catch (final NoSuchMessageException e2) {
          log.info(MSG_WARN_NO_SOURCE, messageId, Locale.ENGLISH);

        }

      } catch (final MissingResourceException e2) {
        log.warn("No message source", e2);

      }
    }

    return null;

  }

  @Override
  public String getMessage(final String messageId, final Object[] parameters) {
    if (messageSource == null) {
      return MessageFormat.format(ERROR_MESSAGES_UNAVAILABLE, new Object[]{messageId});

    } else {
      try {
        final Locale locale = LocaleContextHolder.getLocale();
        return messageSource.getMessage(messageId, parameters, locale);

      } catch (final NoSuchMessageException e) {
        log.info(MSG_WARN_NO_SOURCE, messageId, LocaleContextHolder.getLocale());
        log.debug(MSG_INFO, Locale.ENGLISH);

        try {
          return messageSource.getMessage(messageId, parameters, Locale.ENGLISH);

        } catch (final NoSuchMessageException e2) {
          return MessageFormat.format(ERROR_NO_MESSAGE, new Object[]{messageId});

        }

      } catch (final MissingResourceException e2) {
        return MessageFormat.format(ERROR_NO_MESSAGE, new Object[]{messageId});

      }
    }
  }
  
  @Override
  public String getResponseErrorCode(Throwable throwable) {
    String errorCode = IStatusMessenger.CODES_EXTERNAL_ERROR_GENERIC;
    if (throwable instanceof EaafException) {
      errorCode = ((EaafException) throwable).getErrorId();
      
    }
        
    return errorCode;

  }

  @Override
  public String mapInternalErrorToExternalError(String intErrorCode) {
    // initialize messages
    if (externalError == null) {
      this.externalError = ResourceBundle.getBundle(
          DEFAULT_EXTERNALERROR_RESOURCES,
          DEFAULT_EXTERNALERROR_LOCALES);

    }

    // create the message
    if (externalError == null) {
      log.warn(MessageFormat.format(ERROR_EXTERNALERROR_CODES_UNAVAILABLE, new Object[] { intErrorCode }));
      return IStatusMessenger.CODES_EXTERNAL_ERROR_GENERIC;

    } else {
      try {
        if (StringUtils.isNotEmpty(intErrorCode)) {
          return externalError.getString(intErrorCode);

        } else {
          return IStatusMessenger.CODES_EXTERNAL_ERROR_GENERIC;

        }

      } catch (final MissingResourceException e2) {
        log.info(MessageFormat.format(ERROR_NO_EXTERNALERROR_CODE, new Object[] { intErrorCode }));
        return IStatusMessenger.CODES_EXTERNAL_ERROR_GENERIC;

      }
    }
  }

  @Override
  public void setMessageSource(MessageSource messageSource) {
    this.messageSource = messageSource;

    log.info("Injecting 'StatusMessanger' into 'LogMessageProviderFactory'");
    LogMessageProviderFactory.setStatusMessager(this);
    
  }

}