package at.gv.egiz.eaaf.core.impl.logging;

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

import org.springframework.context.MessageSource;
import org.springframework.context.MessageSourceAware;
import org.springframework.context.NoSuchMessageException;
import org.springframework.context.i18n.LocaleContextHolder;

import at.gv.egiz.eaaf.core.api.IStatusMessenger;
import lombok.extern.slf4j.Slf4j;

/**
 * Basic {@link IStatusMessenger} implementation that operates on Spring {@link MessageSource}.
 * 
 * @author tlenz
 *
 */
@Slf4j
public class SpringBasedBasicStatusMessager implements IStatusMessenger, MessageSourceAware {

  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 MSG_WARN_NO_SOURCE = "MessageCode: {} is NOT SET for locale: {}";
  private static final String MSG_INFO = "Use locale: {} as default";
  
  private MessageSource messageSource;
  
  @Override
  public String getMessage(String messageId, 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.debug(MSG_WARN_NO_SOURCE, messageId, LocaleContextHolder.getLocale());
        log.trace(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 getMessageWithoutDefault(String messageId, 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.debug(MSG_WARN_NO_SOURCE, messageId, LocaleContextHolder.getLocale());
        log.trace(MSG_INFO, Locale.ENGLISH);

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

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

        }

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

      }
    }

    return null;
    
  }

  @Override
  public String getResponseErrorCode(Throwable throwable) {
    return IStatusMessenger.CODES_INTERNAL_ERROR_GENERIC;
    
  }

  @Override
  public String mapInternalErrorToExternalError(String intErrorCode) {
    return IStatusMessenger.CODES_EXTERNAL_ERROR_GENERIC;
    
  }

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

    log.info("Injecting '{}' into 'LogMessageProviderFactory'", this.getClass().getName());
    LogMessageProviderFactory.setStatusMessager(this);

  }
  
}