/*
    * #%L
    * wcm.io
    * %%
    * Copyright (C) 2014 wcm.io
    * %%
    * 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.
   * #L%
   */
  package io.wcm.handler.mediasource.dam.impl;
  
  import org.apache.commons.io.FilenameUtils;
  import org.apache.commons.lang3.StringUtils;
  import org.apache.sling.api.adapter.Adaptable;
  import org.apache.sling.api.adapter.SlingAdaptable;
  import org.apache.sling.api.resource.Resource;
  import org.apache.sling.api.resource.ValueMap;
  import org.apache.sling.api.wrappers.ValueMapDecorator;
  import org.jetbrains.annotations.NotNull;
  import org.jetbrains.annotations.Nullable;
  
  import com.day.cq.dam.api.DamConstants;
  
  import io.wcm.handler.media.Asset;
  import io.wcm.handler.media.CropDimension;
  import io.wcm.handler.media.Dimension;
  import io.wcm.handler.media.Media;
  import io.wcm.handler.media.MediaArgs;
  import io.wcm.handler.media.MediaFileType;
  import io.wcm.handler.media.Rendition;
  import io.wcm.handler.media.UriTemplate;
  import io.wcm.handler.media.UriTemplateType;
  import io.wcm.handler.media.spi.MediaHandlerConfig;
  import io.wcm.handler.mediasource.dam.AssetRendition;
  import io.wcm.handler.mediasource.dam.impl.dynamicmedia.DynamicMediaSupportService;
  import io.wcm.handler.mediasource.dam.impl.weboptimized.WebOptimizedImageDeliveryService;
  import io.wcm.wcm.commons.util.AemObjectReflectionToStringBuilder;
  
  /**
   * {@link Asset} implementation for DAM assets.
   */
  public final class DamAsset extends SlingAdaptable implements Asset {
  
    private final com.day.cq.dam.api.Asset asset;
    private final CropDimension cropDimension;
    private final Integer rotation;
    private final MediaArgs defaultMediaArgs;
    private final DamContext damContext;
  
    /**
     * @param media Media metadata
     * @param asset DAM asset
     * @param mediaHandlerConfig Media handler config
     * @param dynamicMediaSupportService Dynamic media support service
     * @param webOptimizedImageDeliveryService Web optimized image delivery service
     * @param adaptable Adaptable from current context
     */
    public DamAsset(Media media, com.day.cq.dam.api.Asset asset, MediaHandlerConfig mediaHandlerConfig,
        DynamicMediaSupportService dynamicMediaSupportService,
        WebOptimizedImageDeliveryService webOptimizedImageDeliveryService,
        Adaptable adaptable) {
      this.asset = asset;
      this.cropDimension = rescaleCropDimension(asset, media.getCropDimension());
      this.rotation = media.getRotation();
      this.defaultMediaArgs = media.getMediaRequest().getMediaArgs();
      this.damContext = new DamContext(asset, defaultMediaArgs, mediaHandlerConfig,
          dynamicMediaSupportService, webOptimizedImageDeliveryService, adaptable);
    }
  
    /**
     * Crop dimension stored in repository is always calucated against the web-enabled rendition of an asset.
     * Rescale the crop-dimension here once to calculate it against the original image, which will be used for the actual
     * cropping.
     * @param asset Asset
     * @param cropDimension Crop dimension from repository/input parameters
     * @return Rescaled crop dimension
     */
    private static @Nullable CropDimension rescaleCropDimension(@NotNull com.day.cq.dam.api.Asset asset, @Nullable CropDimension cropDimension) {
      if (cropDimension == null) {
        return null;
      }
      return WebEnabledRenditionCropping.getCropDimensionForOriginal(asset, cropDimension);
    }
  
    @Override
    public String getTitle() {
      String title = getPropertyAwareOfArray(DamConstants.DC_TITLE);
      // fallback to asset name if title is empty
      return StringUtils.defaultString(title, damContext.getAsset().getName());
   }
 
   /**
    * Get string value from properties. If value is an array, get first item of array.
    * It might happen that the adobe xmp lib creates an array, e.g. if the asset file already has a title attribute.
    * @param propertyName Property name
    * @return Single value
    */
   private @Nullable String getPropertyAwareOfArray(@NotNull String propertyName) {
     Object valueObject = asset.getMetadataValueFromJcr(propertyName);
     String value = null;
     if (valueObject != null) {
       if (valueObject instanceof Object[]) {
         Object[] valueArray = (Object[])valueObject;
         if (valueArray.length > 0) {
           value = valueArray[0].toString();
         }
       }
       else {
         value = valueObject.toString();
       }
     }
     return StringUtils.defaultIfBlank(value, null);
   }
 
   @Override
   public String getAltText() {
     if (defaultMediaArgs.isDecorative()) {
       return "";
     }
     if (!defaultMediaArgs.isForceAltValueFromAsset() && StringUtils.isNotEmpty(defaultMediaArgs.getAltText())) {
       return defaultMediaArgs.getAltText();
     }
     return StringUtils.defaultString(getDescription(), getTitle());
   }
 
   @Override
   public String getDescription() {
     return getPropertyAwareOfArray(DamConstants.DC_DESCRIPTION);
   }
 
   @Override
   public @NotNull String getPath() {
     return this.damContext.getAsset().getPath();
   }
 
   @Override
   public @NotNull ValueMap getProperties() {
     return new ValueMapDecorator(asset.getMetadata());
   }
 
   @Override
   public Rendition getDefaultRendition() {
     return getRendition(this.defaultMediaArgs);
   }
 
   @Override
   public Rendition getRendition(@NotNull MediaArgs mediaArgs) {
     Rendition rendition = getDamRendition(mediaArgs);
 
     // check if rendition is valid - otherwise return null
     if (StringUtils.isEmpty(rendition.getUrl())) {
       rendition = null;
     }
 
     return rendition;
   }
 
   @Override
   public Rendition getImageRendition(@NotNull MediaArgs mediaArgs) {
     Rendition rendition = getRendition(mediaArgs);
     if (rendition != null && rendition.isImage()) {
       return rendition;
     }
     else {
       return null;
     }
   }
 
   @Override
   public Rendition getDownloadRendition(@NotNull MediaArgs mediaArgs) {
     Rendition rendition = getRendition(mediaArgs);
     if (rendition != null && rendition.isDownload()) {
       return rendition;
     }
     else {
       return null;
     }
   }
 
   /**
    * Get DAM rendition instance.
    * @param mediaArgs Media args
    * @return DAM rendition instance (may be invalid rendition)
    */
   protected Rendition getDamRendition(MediaArgs mediaArgs) {
     return new DamRendition(this.cropDimension, this.rotation, mediaArgs, damContext);
   }
 
   @Override
   @SuppressWarnings({ "unchecked", "null" })
   public <AdapterType> AdapterType adaptTo(Class<AdapterType> type) {
     if (type == com.day.cq.dam.api.Asset.class) {
       return (AdapterType)this.damContext.getAsset();
     }
     if (type == Resource.class) {
       return (AdapterType)this.damContext.getAsset().adaptTo(Resource.class);
     }
     return super.adaptTo(type);
   }
 
   @Override
   public @NotNull UriTemplate getUriTemplate(@NotNull UriTemplateType type) {
     String extension = FilenameUtils.getExtension(damContext.getAsset().getName());
     if (!MediaFileType.isImage(extension) || MediaFileType.isVectorImage(extension)) {
       throw new UnsupportedOperationException("Unable to build URI template for this asset type: " + getPath());
     }
     com.day.cq.dam.api.Rendition original = damContext.getAsset().getOriginal();
     Dimension dimension = AssetRendition.getDimension(original);
     if (dimension == null) {
       throw new IllegalArgumentException("Unable to get dimension for original rendition of asset: " + getPath());
     }
     return new DamUriTemplate(type, dimension, original, null, null, null, damContext);
   }
 
   @Override
   public String toString() {
     return new AemObjectReflectionToStringBuilder(this,
         io.wcm.wcm.commons.util.ToStringStyle.SHORT_PREFIX_OMIT_NULL_STYLE).build();
   }
 
 }