Adobe-Consulting-Services/acs-aem-commons

/*
 * ACS AEM Commons
 *
 * Copyright (C) 2013 - 2023 Adobe
 *
 * 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 com.adobe.acs.commons.httpcache.engine;

import com.adobe.acs.commons.httpcache.exception.HttpCacheDataStreamException;
import com.adobe.acs.commons.httpcache.store.TempSink;

import javax.servlet.http.HttpServletResponse;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**
 * Represents response content to be cached.
 */
public class CacheContent {

    /** Response status **/
    private int status;
    /** Response character encoding */
    private String charEncoding;
    /** Response content type */
    private String contentType;
    /** Response headers */
    private Map<String, List<String>> headers = new HashMap<>();
    /** Response content as input stream */
    private InputStream dataInputStream;
    /** Temp sink attached to this cache content */
    private TempSink tempSink;

    private HttpCacheServletResponseWrapper.ResponseWriteMethod writeMethod;

    /**
     * Construct <code>CacheContent</code> using parameters. Prefer constructing an instance using <code>build</code>
     * method.
     *
     * @param charEncoding
     * @param contentType
     * @param headers
     * @param dataInputStream
     */
    public CacheContent(String charEncoding, String contentType, Map<String, List<String>> headers, InputStream
            dataInputStream){
        this(HttpServletResponse.SC_OK, charEncoding, contentType, headers, dataInputStream, HttpCacheServletResponseWrapper.ResponseWriteMethod.PRINTWRITER);
    }

    /**
     * Construct <code>CacheContent</code> using parameters. Prefer constructing an instance using <code>build</code>
     * method.
     *
     * @param charEncoding
     * @param contentType
     * @param headers
     * @param dataInputStream
     * @param writeMethod
     */
    public CacheContent(String charEncoding, String contentType, Map<String, List<String>> headers, InputStream
            dataInputStream,HttpCacheServletResponseWrapper.ResponseWriteMethod writeMethod) {

        this(HttpServletResponse.SC_OK, charEncoding, contentType, headers, dataInputStream, writeMethod);
    }


    /**
     * Construct <code>CacheContent</code> using parameters. Prefer constructing an instance using <code>build</code>
     * method.
     *
     * @param status
     * @param charEncoding
     * @param contentType
     * @param headers
     * @param dataInputStream
     */
    public CacheContent(int status, String charEncoding, String contentType, Map<String, List<String>> headers, InputStream
            dataInputStream) {
        this.writeMethod = HttpCacheServletResponseWrapper.ResponseWriteMethod.PRINTWRITER;
        this.status = status;
        this.charEncoding = charEncoding;
        this.contentType = contentType;
        this.headers = headers;
        this.dataInputStream = dataInputStream;
    }

    /**
     * Construct <code>CacheContent</code> using parameters. Prefer constructing an instance using <code>build</code>
     * method.
     *
     * @param status
     * @param charEncoding
     * @param contentType
     * @param headers
     * @param dataInputStream
     * @param writeMethod
     */
    public CacheContent(int status, String charEncoding, String contentType, Map<String, List<String>> headers, InputStream
            dataInputStream, HttpCacheServletResponseWrapper.ResponseWriteMethod writeMethod) {

        this.writeMethod = writeMethod;
        this.status = status;
        this.charEncoding = charEncoding;
        this.contentType = contentType;
        this.headers = headers;
        this.dataInputStream = dataInputStream;
    }

    /**
     * No argument constructor for the build method.
     */
    public CacheContent() {
    }
    
    /**
     * Construct from the custom servlet response wrapper..
     *
     * @param responseWrapper
     * @param headers
     * @return
     */
    public CacheContent build(HttpCacheServletResponseWrapper responseWrapper,int status, String charEncoding, String contentType, Map<String, List<String>> headers) throws HttpCacheDataStreamException {
        this.status = status;

        // Extract information from response and populate state of the instance.
        this.charEncoding = charEncoding;
        this.contentType = contentType;

        // Extracting header K,V.
        this.headers.putAll(headers);

        // Get hold of the temp sink.
        this.tempSink = responseWrapper.getTempSink();

        // Get hold of the response content available in sink.
        this.dataInputStream = responseWrapper.getTempSink().createInputStream();
        this.writeMethod = responseWrapper.getWriteMethod();

        return this;
    }

    /**
     * Get status code.
     */
    public int getStatus() {
        return status;
    }

    /**
     * Get character encoding.
     *
     * @return
     */
    public String getCharEncoding() {
        return charEncoding;
    }

    /**
     * Get content type.
     *
     * @return
     */
    public String getContentType() {
        return contentType;
    }

    /**
     * Get headers.
     *
     * @return Headers in map of list.
     */
    public Map<String, List<String>> getHeaders() {
        return headers;
    }

    /**
     * Get input stream of response content
     *
     * @return
     */
    public InputStream getInputDataStream() {
        return dataInputStream;
    }

    /**
     * Get the temp size attached to this cache content.
     * @return
     */
    public TempSink getTempSink(){
        return this.tempSink;
    }

    public HttpCacheServletResponseWrapper.ResponseWriteMethod getWriteMethod() {
        return writeMethod;
    }
}