Subversion Repositories SmartDukaan

package in.shop2020.serving.controllers;

import in.shop2020.model.v1.catalog.InventoryServiceException;
import in.shop2020.model.v1.catalog.InventoryService.Client;
import in.shop2020.serving.utils.FileUtils;
import in.shop2020.serving.utils.Utils;
import in.shop2020.thrift.clients.CatalogServiceClient;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.apache.log4j.Logger;
import org.apache.struts2.convention.annotation.Action;
import org.apache.thrift.TException;

/**
 * 
 * @author chandranshu
 *
 */
@SuppressWarnings("serial")
public class HomeController extends BaseController {

        private static Logger logger = Logger.getLogger(Class.class);
        
        private static List<String> bestDealSnippets = null;
        private static List<String> bestSellerSnippets = null;
        private static List<String> latestArrivalSnippets = null;
        
        public HomeController(){
                super();
        }

    /**
     * Renders the home page. Loads the snippets for best deals, best sellers
     * and latest arrivals if they haven't been loaded already.
     * 
     * @return Name of the view to render.
     * @throws SecurityException
     * @throws IOException
     */
        @Action("/")
    public String index() throws SecurityException, IOException {
        logger.debug("userinfo:" + userinfo.toString());
        logger.info("Rendering the home page");
        
        if(bestDealSnippets == null || bestSellerSnippets == null || latestArrivalSnippets == null){
            logger.info("Cache miss: Reloading best deals, best sellers and latest arrivals");
            setSnippets();          
        }       
        
        return "index";
    }

    /**
     * Renders the home page but always loads the snippets for best deals, best
     * sellers and latest arrivals unconditionally. Should be used to reset the
     * snippets.
     * 
     * @return Name of the view to render.
     * @throws SecurityException
     * @throws IOException
     */
        @Action("/refresh-home")
        public String destroy() throws SecurityException, IOException{
            logger.info("Reloading best deals, best sellers and latest arrivals");
            setSnippets();
            return "index";
        }
        
        public List<String> getBestDealSnippets(){
                return bestDealSnippets; 
        }
        
        public List<String> getBestSellerSnippets(){
                return bestSellerSnippets; 
        }
        
        public List<String> getLatestArrivalSnippets(){
                return latestArrivalSnippets;
        }

        /**
         * Loads the snippets for best deals, best sellers and latest arrivals
         * into memory.
         */
    private void setSnippets() {
        List<Long> bestDealCatalogIds = null;
        List<Long> bestSellerCatalogIds = null;
        List<Long> latestArrivalCatalogIds = null;
        
        int bestSellerCount = 4;
        int latestArrivalCount = 4;
        
        try {
            CatalogServiceClient catalogServiceClient = new CatalogServiceClient();
            Client client = catalogServiceClient.getClient();
            
            //Get top 4 best deals 
            bestDealCatalogIds = client.getBestDealsCatalogIds(0, 4, null, -1);
            
            //Get top 8 best sellers b'coz 4 of them may overlap with best deals.
            bestSellerCatalogIds = client.getBestSellersCatalogIds(0, 8, null, -1);
            bestSellerCatalogIds.removeAll(bestDealCatalogIds);
            if(bestSellerCatalogIds.size() < bestSellerCount)
                bestSellerCount = bestSellerCatalogIds.size();
            
            //Get top 12 latest arrivals b'coz 4 of them may overlap with best deals
            //while another 4 may overlap with best sellers.
            latestArrivalCatalogIds = client.getLatestArrivalsCatalogIds(0, 12, null, 10003);
            latestArrivalCatalogIds.removeAll(bestDealCatalogIds);
            latestArrivalCatalogIds.removeAll(bestSellerCatalogIds.subList(0, bestSellerCount)); //We're only considering the first 4 best sellers for removal.
            if(latestArrivalCatalogIds.size() < latestArrivalCount)
                latestArrivalCount = latestArrivalCatalogIds.size();
        } catch (InventoryServiceException e) {
            logger.error("Error while fetching data from the catalog service", e);
        } catch (TException e) {
            logger.error("Error while fetching data from the catalog service", e);
        } catch (Exception e) {
            logger.error("Unexpected exception", e);
        }
        
        bestDealSnippets = getSnippets(bestDealCatalogIds);
        bestSellerSnippets = getSnippets(bestSellerCatalogIds.subList(0, bestSellerCount));
        latestArrivalSnippets = getSnippets(latestArrivalCatalogIds).subList(0, latestArrivalCount);
    }
        
    /**
     * Returns a list of snippets to be used on the home page corresponding to
     * the given catalog ids. The snippets are in the same order as the ids in
     * the input list. In case a snippet is not found for an entity, this method
     * simply logs the problem and moves on.
     * 
     * @param catalogIds
     *            Ids of the entities which we want to show.
     * @return The snippet corresponding to each catalog entity
     */
    private List<String> getSnippets(List<Long> catalogIds) {
        List<String> snippets = new ArrayList<String>();
        if(catalogIds == null)
            return snippets;
        for(Long item: catalogIds){
            try{
                snippets.add(FileUtils.read( Utils.EXPORT_ENTITIES_PATH + item + File.separator +"HomeSnippet.html"));
            }catch(IOException ioex){
                logger.error("Unable to get home page snippet for " + item, ioex);
            }
        }
        return snippets;
    }
}