EDIT

/**

* Copyright (C) 2009 EDIT

* European Distributed Institute of Taxonomy

* http://www.e-taxonomy.eu

*

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.cdm.remote.controller;

import java.io.IOException;

import java.io.UnsupportedEncodingException;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Collection;

import java.util.List;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.RequestMapping;

import eu.etaxonomy.cdm.api.service.IService;

import eu.etaxonomy.cdm.api.service.pager.Pager;

import eu.etaxonomy.cdm.api.service.pager.impl.DefaultPagerImpl;

import eu.etaxonomy.cdm.api.util.UserHelper;

import eu.etaxonomy.cdm.model.common.CdmBase;

import eu.etaxonomy.cdm.persistence.dao.hibernate.common.DaoBase;

import eu.etaxonomy.cdm.remote.controller.util.PagerParameters;

/**

 * Abstract controller class for CDM Rest service controllers which return entities or DTOs

 * from the underlying data base. Implementations of this class are primarily bound to a

 * specific cdm service class and thus are operating primarily on a specific cdm base type.

 *

 * This class guarantees consistent use of init-strategies and harmonizes the logging of full

 * request urls with query parameters.

 *

 * @author a.kohlbecker

 * @since 23.06.2009

 *

 * @param <T>

 * @param <SERVICE>

 */

public abstract class AbstractController<T extends CdmBase, SERVICE extends IService<T>> {

    protected static final List<String> DEFAULT_INIT_STRATEGY = Arrays.asList(new String []{

            "$"

    });

    protected static final Integer DEFAULT_PAGE_SIZE = PagerParameters.DEFAULT_PAGESIZE;

    /**

     * Default thread priority for long term processes which are running in

     * separate threads. These batch processes are usually monitored with the

     * {@link ProgressMonitorController}. This value must be lower than

     * {@link Thread#NORM_PRIORITY}

     */

    public static final int DEFAULT_BATCH_THREAD_PRIORITY = 3;

    protected static final boolean NO_UNPUBLISHED = DaoBase.NO_UNPUBLISHED;

    protected static final boolean INCLUDE_UNPUBLISHED = DaoBase.INCLUDE_UNPUBLISHED;

    protected SERVICE service;

    @Autowired

    protected UserHelper userHelper;

    public abstract void setService(SERVICE service);

    protected List<String> initializationStrategy = DEFAULT_INIT_STRATEGY;

    /**

     * Set the default initialization strategy for this controller.

     *

     * @param initializationStrategy

     */

    public final void setInitializationStrategy(List<String> initializationStrategy) {

        this.initializationStrategy = initializationStrategy;

    }

    /**

     * Provides access to the default initialization strategy.

     * The default initialization strategy is predefined for all controllers in

     * {@link #DEFAULT_INIT_STRATEGY} but can be altered by

     * concrete implementations by utilizing {@link #setInitializationStrategy(List)}

     * in the constructor of the specific controller.

     *

     * @return the default initialization strategy

     */

    public final List<String> getInitializationStrategy() {

        return this.initializationStrategy;

    }

    /**

     * Returns the HTTP request path and query parameters as string

     *

     * @param request

     * @return request path and query parameters as string.

     */

    public static String requestPathAndQuery(HttpServletRequest request) {

        if(request == null) {

            return "";

        }

        StringBuilder b = new StringBuilder();

        b.append(request.getMethod()).append(": ");

        b.append(request.getRequestURI());

        String query = request.getQueryString();

        if(query != null) {

            b.append("?").append(query);

        }

        return b.toString();

    }

    /**

     * This method is useful to read path parameters from request urls in methods where the method has been annotated with a

     * {@link RequestMapping} having wildcards as trailing characters like in <code>@RequestMapping("identifier/**")</code>.

     * <p>

     * Reads the path part following pattern passed as <code>basePath</code> and returns it is urldecoded String.

     * The <code>basepath</code> usually is the combination of the class level and method level RequestMappings e.g.:

     * <code>"/registration/identifier/"</code>

     *

     * @param basePath

     *      The base path of the controller method.

     * @param request

     * @return

     */

    protected String readPathParameter(HttpServletRequest request, String basePath) {

        String pathParameter = request.getRequestURI().replaceFirst("^(?:.*)" + basePath , "");

        if(pathParameter != null){

            try {

                pathParameter = java.net.URLDecoder.decode(pathParameter, "UTF-8");

                pathParameter = pathParameter.replaceAll("\\.json$|\\.xml$", "");

            } catch (UnsupportedEncodingException e) {

                // should never happen

                throw new RuntimeException(e);

            }

        }

        return pathParameter;

    }

    protected <T extends CdmBase> Pager<T> pagerForSubCollectionOf(Collection<T> c, Integer pageNumber, Integer pageSize, HttpServletResponse response) throws IOException {

        PagerParameters pagerParameters = new PagerParameters(pageSize, pageNumber);

        pagerParameters.normalizeAndValidate(response);

        int subCollectionStart = pagerParameters.getPageIndex() * pagerParameters.getPageSize();

        List<T> sub_c = subCollection(c, subCollectionStart, pagerParameters.getPageSize());

        Pager<T> p = new DefaultPagerImpl<>(pageNumber, c.size(), pagerParameters.getPageSize(), sub_c);

        return p;

    }

    protected <E> List<E> subCollection(Collection<? extends E> c, Integer start, Integer length) {

        List<E> sub_c = new ArrayList<E>(length);

        if(c.size() > length){

            E[] a = (E[]) c.toArray();

            for(int i = start; i < start + length; i++){

                sub_c.add(a[i]);

            }

        } else {

            sub_c.addAll(c);

        }

        return sub_c;

    }

}