/**
 * The contents of this file are subject to the license and copyright
 * detailed in the LICENSE and NOTICE files at the root of the source
 * tree and available online at
 *
 * http://www.dspace.org/license/
 */
package org.dspace.xmlworkflow.state.actions.userassignment;

import org.dspace.authorize.AuthorizeException;
import org.dspace.core.*;
import org.dspace.eperson.EPerson;
import org.dspace.xmlworkflow.state.Step;
import org.dspace.xmlworkflow.storedcomponents.XmlWorkflowItem;
import org.dspace.xmlworkflow.*;
import org.dspace.xmlworkflow.state.actions.ActionResult;
import org.dspace.xmlworkflow.XmlWorkflowManager;

import javax.mail.MessagingException;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.sql.SQLException;
import java.util.ArrayList;

/**
 * Processing class for an action where x number of users
 * have to accept a task from a designated pool
 * 
 * @author Bram De Schouwer (bram.deschouwer at dot com)
 * @author Kevin Van de Velde (kevin at atmire dot com)
 * @author Ben Bosman (ben at atmire dot com)
 * @author Mark Diggory (markd at atmire dot com)
 */
public class ClaimAction extends UserSelectionAction {
    @Override
    public void activate(Context context, XmlWorkflowItem wfItem) throws SQLException, IOException, AuthorizeException {
        Step owningStep = getParent().getStep();

        RoleMembers allroleMembers = getParent().getStep().getRole().getMembers(context, wfItem);
        // Create pooled tasks for each member of our group
        if(allroleMembers != null && (allroleMembers.getGroups().size() > 0 || allroleMembers.getEPersons().size() > 0)){
            XmlWorkflowManager.createPoolTasks(context, wfItem, allroleMembers, owningStep, getParent());
            alertUsersOnActivation(context, wfItem, allroleMembers);
        }
        else
            log.info(LogManager.getHeader(context, "warning while activating claim action", "No group or person was found for the following roleid: " + getParent().getStep().getRole().getId()));


    }

    @Override
    public ActionResult execute(Context c, XmlWorkflowItem wfi, Step step, HttpServletRequest request) throws SQLException, AuthorizeException, IOException {
        //Check if we are accept this task, or accepting multiple tasks
        if(request.getParameter("submit_take_task") != null || request.getParameter("submit_take_tasks") != null){
            //Add a claimed user to our task
            WorkflowRequirementsManager.addClaimedUser(c, wfi, step, c.getCurrentUser());

            return new ActionResult(ActionResult.TYPE.TYPE_OUTCOME, ActionResult.OUTCOME_COMPLETE);
        }else{
            return new ActionResult(ActionResult.TYPE.TYPE_CANCEL);
        }
    }

    @Override
    public void alertUsersOnActivation(Context c, XmlWorkflowItem wfi, RoleMembers roleMembers) throws IOException, SQLException {
        try{
            XmlWorkflowManager.alertUsersOnTaskActivation(c, wfi, "submit_task", roleMembers.getAllUniqueMembers(c),
                    //The arguments
                    wfi.getItem().getName(),
                    wfi.getCollection().getName(),
                    wfi.getSubmitter().getFullName(),
                    //TODO: message
                    "New task available.",
                    XmlWorkflowManager.getMyDSpaceLink()
            );
        } catch (MessagingException e) {
            log.info(LogManager.getHeader(c, "error emailing user(s) for claimed task", "step: " + getParent().getStep().getId() + " workflowitem: " + wfi.getID()));
        }


    }

    public void regenerateTasks(Context c, XmlWorkflowItem wfi, RoleMembers roleMembers) throws SQLException, AuthorizeException {
        if(roleMembers != null && (roleMembers.getEPersons().size() > 0 || roleMembers.getGroups().size() >0)){
            //Create task for the users left
            XmlWorkflowManager.createPoolTasks(c, wfi, roleMembers, getParent().getStep(), getParent());
        }
        else
            log.info(LogManager.getHeader(c, "warning while activating claim action", "No group or person was found for the following roleid: " + getParent().getStep().getId()));

    }

    @Override
    public boolean isFinished(XmlWorkflowItem wfi) {
        return false;
    }

    public boolean isValidUserSelection(Context context, XmlWorkflowItem wfi, boolean hasUI) throws WorkflowConfigurationException, SQLException {
        //A user claim action always needs to have a UI, since somebody needs to be able to claim it
        if(hasUI){
            Step step = getParent().getStep();
            //First of all check if our step has a role
            Role role = step.getRole();
            if(role != null){
                //We have a role, check if we have a group to with that role
                RoleMembers roleMembers = role.getMembers(context, wfi);

                ArrayList<EPerson> epersons = roleMembers.getAllUniqueMembers(context);
                return !(epersons.size() == 0 || step.getRequiredUsers() > epersons.size());
            } else {
                // We don't have a role and do have a UI so throw a workflow exception
                throw new WorkflowConfigurationException("The next step is invalid, since it doesn't have a valid role");
            }
        }else
            return true;

    }

    @Override
    public boolean usesTaskPool() {
        return true;
    }

}