package util;

import com.google.protobuf.InvalidProtocolBufferException;
import meerkat.VoterRegistryMessage;
import meerkat.protobuf.BulletinBoardAPI;

import java.text.ParseException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**
 * Created by Vladimir Eliezer Tokarev  on 1/15/2016.
 * adds extra functionality to Messages collections
 */
public abstract class CollectionMessagesUtils {

    /**
     * Converts lost of UnsignedBulletinBoardMessage to VoterRegistryMessags
     * @param messages list<VoterRegistryMessage>
     * @return List<VoterRegistryMessage>
     */
   public static List<VoterRegistryMessage> ConvertToVoterRegistryMessages(List<BulletinBoardAPI.UnsignedBulletinBoardMessage> messages){
       return messages.stream().map(VoterRegistryMessage::new).collect(Collectors.toList());
   }
    
    /**
     * Gets map of GroupId to basicMessage, where the basicMessages are the last actions for those groups
     * @param messages List<VoterRegistryMessage>
     * @return     Map{String:VoterRegistryMessage}
     * @throws ParseException
     */
    public static Map<String, VoterRegistryMessage> GetLatestGroupsActions(List<VoterRegistryMessage> messages) throws ParseException {

            Map<String, VoterRegistryMessage> groupIdToMessage = new HashMap<>();

        // iterate trough all the messages and put into the map the last updated groups actions

        for (VoterRegistryMessage message : messages) {
            String groupId = message.GetWantedTagFromBasicMessage(RegistryTags.GROUP_ID_TAG);
            VoterRegistryMessage temp = groupIdToMessage.get(groupId);

            if (temp != null) {
                if (temp != message) {
                    if (temp.GetBasicMessageActionTimestamp().before(message.GetBasicMessageActionTimestamp())) {
                        groupIdToMessage.put(groupId, message);
                    }
                }
            }
        }

        return groupIdToMessage;
    }

    /**
     * Gets list of groups ids of the basicMessages that carried the adding to group tag
     * @param groupIdToMessage Map<String, VoterRegistryMessage>
     * @return List<String>
     */
     public static List<String> GetListOfGroupIds(Map<String, VoterRegistryMessage>  groupIdToMessage)  {
        List<String> groupsIds = new ArrayList<>();

         groupIdToMessage.values().stream().filter(VoterRegistryMessage::IsGroupAdding).forEach(message -> {
             String groupId = message.GetWantedTagFromBasicMessage(RegistryTags.GROUP_ID_TAG);
             groupsIds.add(groupId);
         });
        return groupsIds;
    }

    /**
     * Gets all the basic messages from bulletin board messages
     * @param listOfMessages list of bulletin board messages
     * @return List<UnsignedBulletinBoardMessage>
     * @throws InvalidProtocolBufferException
     */
    public static List<BulletinBoardAPI.UnsignedBulletinBoardMessage> GetUnsignedBulletinBoardMessages(
            List<BulletinBoardAPI.BulletinBoardMessage> listOfMessages) throws InvalidProtocolBufferException {
        return listOfMessages.stream().map(BulletinBoardAPI.BulletinBoardMessage::getMsg).collect(Collectors.toList());
    }
}