/**
    * Copyright 2004-2014 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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.kuali.common.aws.cloudfront;
  
  import java.io.ByteArrayInputStream;
  import java.io.InputStream;
  import java.text.SimpleDateFormat;
  import java.util.List;
  import java.util.TimeZone;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.common.aws.AmazonWebServiceRequestType;
  import org.kuali.common.aws.TypedRequest;
  import org.kuali.common.aws.s3.old.BucketContext;
  import org.kuali.common.util.Str;
  
  import com.amazonaws.services.s3.model.CopyObjectRequest;
  import com.amazonaws.services.s3.model.ObjectListing;
  import com.amazonaws.services.s3.model.ObjectMetadata;
  import com.amazonaws.services.s3.model.PutObjectRequest;
  import com.amazonaws.services.s3.model.S3ObjectSummary;
  
  public class CloudFrontUtils {
  
  	private static final String INDEX_METADATA_KEY = "maven-cloudfront-plugin-index";
  	private static final String INDEX_CONTENT_TYPE = "text/html";
  
  	/**
  	 * Return a date formatter for the indicated format and timezone.
  	 */
  	public static SimpleDateFormat getSimpleDateFormat(String format, String timezone) {
  		SimpleDateFormat sdf = new SimpleDateFormat(format);
  		sdf.setTimeZone(TimeZone.getTimeZone(timezone));
  		return sdf;
  	}
  
  	/**
  	 * An <code>ObjectListing</code> is the equivalent of typing <code>ls</code> in a directory on a file system.
  	 */
  	public static String getFirstMatchingKey(ObjectListing listing, List<String> filenames) {
  		// Cycle through the list of files in this directory
  		for (S3ObjectSummary summary : listing.getObjectSummaries()) {
  			String objectKey = getFirstMatchingKey(summary.getKey(), listing.getPrefix(), filenames);
  			if (objectKey != null) {
  				return objectKey;
  			}
  		}
  		return null;
  	}
  
  	public static String getFirstMatchingKey(String objectKey, String prefix, List<String> filenames) {
  		// Cycle through the list of filenames
  		for (String filename : filenames) {
  			// Append the file name to the key for this directory
  			String completeKey = prefix + filename;
  			// We found a filename in this directory that matches what we are looking for
  			if (StringUtils.equals(objectKey, completeKey)) {
  				return completeKey;
  			}
  		}
  		return null;
  	}
  
  	/**
  	 * Create a CopyObjectRequest with an ACL set to PublicRead
  	 */
  	public static CopyObjectRequest getCopyObjectRequest(String bucket, String src, String dst) {
  		CopyObjectRequest request = new CopyObjectRequest(bucket, src, bucket, dst);
  		request.setCannedAccessControlList(CloudFrontConstants.DEFAULT_ACL);
  		return request;
  	}
  
  	/**
  	 * Create a PutObjectRequest from the html. The PutObjectRequest sets the content type to <code>text/html</code>, sets the ACL to <code>PublicRead</code>, and adds the metadata
  	 * <code>maven-cloudfront-plugin-index=true</code>
  	 */
  	public static PutObjectRequest getPutHtmlRequest(String bucket, String cacheControl, String html, String key) {
  
  		// Setup an InputStream that reads from the HTML string
  		InputStream in = new ByteArrayInputStream(html.getBytes());
  
  		// Create some metadata for identifying this S3 object as an index
  		ObjectMetadata om = new ObjectMetadata();
  		om.setCacheControl(cacheControl);
  		om.setContentType(INDEX_CONTENT_TYPE);
  		om.setContentLength(html.length());
 		om.addUserMetadata(INDEX_METADATA_KEY, "true");
 
 		// Create a request object
 		PutObjectRequest request = new PutObjectRequest(bucket, key, in, om);
 		request.setCannedAcl(CloudFrontConstants.DEFAULT_ACL);
 		return request;
 	}
 
 	public static TypedRequest getTypedRequestWithoutTrailingDelimiter(BucketContext context, String cacheControl, ObjectListing listing, String html) {
 		// Create s3://bucket/foo/bar
 		PutObjectRequest index = getPutHtmlRequestWithoutTrailingDelimiter(context, cacheControl, listing, html);
 		return new TypedRequest(index, AmazonWebServiceRequestType.PUT_OBJECT);
 	}
 
 	/**
 	 * This does one of two things. It either copies <code>/foo/bar/index.html to /foo/bar/</code> OR creates <code>/foo/bar/</code> from <code>html</code>
 	 */
 	public static TypedRequest getTypedRequest(String bucket, String cacheControl, String welcomeFileKey, ObjectListing listing, String html) {
 		if (welcomeFileKey == null) {
 			// Create s3://bucket/foo/bar/
 			PutObjectRequest put = getPutHtmlRequest(bucket, cacheControl, html, listing.getPrefix());
 			return new TypedRequest(put, AmazonWebServiceRequestType.PUT_OBJECT);
 		} else {
 			// Copy s3://bucket/foo/bar/index.html -> s3://bucket/foo/bar/
 			CopyObjectRequest copy = getCopyObjectRequest(bucket, welcomeFileKey, listing.getPrefix());
 			return new TypedRequest(copy, AmazonWebServiceRequestType.COPY_OBJECT);
 		}
 	}
 
 	public static PutObjectRequest getPutHtmlRequestWithoutTrailingDelimiter(BucketContext context, String cacheControl, ObjectListing listing, String html) {
 		String delimiter = context.getDelimiter();
 		String objectKey = Str.removeSuffix(listing.getPrefix(), delimiter);
 		return getPutHtmlRequest(context.getName(), cacheControl, html, objectKey);
 	}
 
 	public static PutObjectRequest getPutHtmlRequest(BucketContext context, String cacheControl, ObjectListing listing, String html) {
 		return getPutHtmlRequest(context.getName(), cacheControl, html, listing.getPrefix());
 	}
 }