/*
    * Copyright 2012-2025 CodeLibs Project and the Others.
    *
    * Licensed 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.codelibs.fess.storage;
  
  import java.util.Locale;
  
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.codelibs.core.lang.StringUtil;
  import org.codelibs.fess.mylasta.direction.FessConfig;
  import org.codelibs.fess.util.ComponentUtil;
  
  /**
   * Factory for creating appropriate StorageClient based on configuration.
   */
  public final class StorageClientFactory {
  
      private static final Logger logger = LogManager.getLogger(StorageClientFactory.class);
  
      private StorageClientFactory() {
          // Utility class
      }
  
      /**
       * Auto-detect storage type from endpoint URL.
       *
       * @param endpoint the storage endpoint URL
       * @return detected storage type
       */
      public static StorageType detectStorageType(final String endpoint) {
          if (StringUtil.isBlank(endpoint)) {
              // Default to S3 if no endpoint (uses AWS default)
              return StorageType.S3;
          }
  
          final String lowerEndpoint = endpoint.toLowerCase(Locale.ROOT);
  
          // GCS patterns
          if (lowerEndpoint.contains("storage.googleapis.com") || lowerEndpoint.contains(".storage.cloud.google.com")) {
              return StorageType.GCS;
          }
  
          // S3 patterns
          if (lowerEndpoint.contains(".amazonaws.com") || lowerEndpoint.contains("s3.") || lowerEndpoint.contains("s3-")) {
              return StorageType.S3;
          }
  
          // Default to S3-compatible (MinIO, etc.)
          return StorageType.S3_COMPAT;
      }
  
      /**
       * Creates a StorageClient based on FessConfig.
       *
       * @param fessConfig the Fess configuration
       * @return configured StorageClient
       */
      public static StorageClient createClient(final FessConfig fessConfig) {
          final String endpoint = fessConfig.getStorageEndpoint();
          final String accessKey = fessConfig.getStorageAccessKey();
          final String secretKey = fessConfig.getStorageSecretKey();
          final String bucket = fessConfig.getStorageBucket();
  
          // Get explicit type or auto-detect
          final String typeStr = fessConfig.getStorageType();
          final StorageType type;
          if (StringUtil.isBlank(typeStr) || "auto".equalsIgnoreCase(typeStr)) {
              type = detectStorageType(endpoint);
              if (logger.isDebugEnabled()) {
                  logger.debug("Auto-detected storage type: {} for endpoint: {}", type, endpoint);
              }
          } else {
              type = parseStorageType(typeStr);
          }
  
          switch (type) {
          case GCS:
              return new GcsStorageClient(fessConfig.getStorageProjectId(), bucket, endpoint, fessConfig.getStorageCredentialsPath());
          case S3:
          case S3_COMPAT:
          default:
              return new S3StorageClient(endpoint, accessKey, secretKey, bucket, fessConfig.getStorageRegion());
          }
      }
  
      /**
      * Creates a StorageClient using the default FessConfig.
      *
      * @return configured StorageClient
      */
     public static StorageClient createClient() {
         return createClient(ComponentUtil.getFessConfig());
     }
 
     /**
      * Parses a storage type string to StorageType enum.
      *
      * @param typeStr the type string (s3, gcs, s3_compat, auto)
      * @return parsed StorageType
      */
     private static StorageType parseStorageType(final String typeStr) {
         final String upper = typeStr.toUpperCase(Locale.ROOT);
         try {
             return StorageType.valueOf(upper);
         } catch (final IllegalArgumentException e) {
             logger.warn("Unknown storage type: {}, defaulting to S3_COMPAT", typeStr);
             return StorageType.S3_COMPAT;
         }
     }
 }