/**
 * The contents of this file are subject to the OpenMRS Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://license.openmrs.org
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
 * License for the specific language governing rights and limitations
 * under the License.
 *
 * Copyright (C) OpenMRS, LLC.  All Rights Reserved.
 */
package org.openmrs.web.controller.program;

import java.util.HashSet;
import java.util.Set;
import java.util.StringTokenizer;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.openmrs.ProgramWorkflow;
import org.openmrs.ProgramWorkflowState;
import org.openmrs.api.APIException;
import org.openmrs.api.ProgramWorkflowService;
import org.openmrs.api.context.Context;
import org.openmrs.web.WebConstants;
import org.springframework.beans.propertyeditors.CustomNumberEditor;
import org.springframework.dao.DataIntegrityViolationException;
import org.springframework.validation.BindException;
import org.springframework.web.bind.ServletRequestDataBinder;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.SimpleFormController;
import org.springframework.web.servlet.view.RedirectView;

public class WorkflowFormController extends SimpleFormController {

	protected final Log log = LogFactory.getLog(getClass());

	protected void initBinder(HttpServletRequest request, ServletRequestDataBinder binder) throws Exception {
		super.initBinder(request, binder);
		binder.registerCustomEditor(java.lang.Integer.class, new CustomNumberEditor(java.lang.Integer.class, true));
	}

	/**
	 * This is called prior to displaying a form for the first time. It tells Spring the
	 * form/command object to load into the request
	 *
	 * @see org.springframework.web.servlet.mvc.AbstractFormController#formBackingObject(javax.servlet.http.HttpServletRequest)
	 */
	protected Object formBackingObject(HttpServletRequest request) throws ServletException {
		log.debug("called formBackingObject");

		ProgramWorkflow wf = null;

		if (Context.isAuthenticated()) {
			ProgramWorkflowService ps = Context.getProgramWorkflowService();
			String programWorkflowId = request.getParameter("programWorkflowId");
			if (programWorkflowId != null)
				wf = ps.getWorkflow(Integer.valueOf(programWorkflowId));

			if (wf == null)
				throw new IllegalArgumentException("Can't find workflow");
		}

		if (wf == null)
			wf = new ProgramWorkflow();

		return wf;
	}

	/**
	 * The onSubmit function receives the form/command object that was modified by the input form
	 * and saves it to the db
	 *
	 * @see org.springframework.web.servlet.mvc.SimpleFormController#onSubmit(javax.servlet.http.HttpServletRequest,
	 *      javax.servlet.http.HttpServletResponse, java.lang.Object,
	 *      org.springframework.validation.BindException)
	 */
	protected ModelAndView onSubmit(HttpServletRequest request, HttpServletResponse response, Object obj,
	        BindException errors) throws Exception {
		log.debug("about to save " + obj);

		HttpSession httpSession = request.getSession();

		String view = getFormView();

		if (Context.isAuthenticated()) {
			ProgramWorkflow wf = (ProgramWorkflow) obj;

			if (request.getParameter("delete") != null) {
				String detstatesStr = request.getParameter("deletedStates");
				for (StringTokenizer st = new StringTokenizer(detstatesStr, "|"); st.hasMoreTokens();) {
					String str = st.nextToken();
					String[] tmp = str.split(",");
					Integer conceptId = Integer.valueOf(tmp[0]);
					ProgramWorkflowState pws = null;
					for (ProgramWorkflowState s : wf.getStates()) {
						if (s.getConcept().getConceptId().equals(conceptId)) {
							pws = s;
							break;
						}
					}
					if (pws == null) {
						System.out.println("not found ");
					} else
						System.out.println("found ");
					try {
						Context.getProgramWorkflowService().deleteProgramWorkflowState(pws);
					}
					catch (DataIntegrityViolationException e) {
						httpSession.setAttribute(WebConstants.OPENMRS_ERROR_ATTR, "error.object.inuse.cannot.purge");
					}
					catch (APIException e) {
						httpSession.setAttribute(WebConstants.OPENMRS_ERROR_ATTR, "error.general: "
						        + e.getLocalizedMessage());
					}

					view = getSuccessView();
					//httpSession.setAttribute(WebConstants.OPENMRS_MSG_ATTR, "Workflow.saved");
					return new ModelAndView(new RedirectView(view));

				}

				/*try {
					es.purgeEncounterType(encounterType);
					httpSession.setAttribute(WebConstants.OPENMRS_MSG_ATTR, "EncounterType.purgedSuccessfully");
					view = getSuccessView();
				}
				catch (DataIntegrityViolationException e) {
					httpSession.setAttribute(WebConstants.OPENMRS_ERROR_ATTR, "error.object.inuse.cannot.purge");
					view = "encounterType.form?encounterTypeId=" + encounterType.getEncounterTypeId();
				}
				catch (APIException e) {
					httpSession.setAttribute(WebConstants.OPENMRS_ERROR_ATTR, "error.general: " + e.getLocalizedMessage());
					view = "encounterType.form?encounterTypeId=" + encounterType.getEncounterTypeId();
				}*/
			}

			// get list of states, and update the command object
			String statesStr = request.getParameter("newStates");
			// This is a brute-force algorithm, but n will be small.
			Set<Integer> doneSoFar = new HashSet<Integer>(); // concept ids done so far
			for (StringTokenizer st = new StringTokenizer(statesStr, "|"); st.hasMoreTokens();) {
				String str = st.nextToken();
				String[] tmp = str.split(",");
				Integer conceptId = Integer.valueOf(tmp[0]);
				doneSoFar.add(conceptId);
				ProgramWorkflowState pws = null;
				for (ProgramWorkflowState s : wf.getStates()) {
					if (s.getConcept().getConceptId().equals(conceptId)) {
						pws = s;
						break;
					}
				}
				if (pws == null) {
					pws = new ProgramWorkflowState();
					pws.setConcept(Context.getConceptService().getConcept(conceptId));
					wf.addState(pws);
				} else {
					// un-retire if necessary
					if (pws.isRetired()) {
						pws.setRetired(false);
					}
				}
				pws.setInitial(Boolean.valueOf(tmp[1]));
				pws.setTerminal(Boolean.valueOf(tmp[2]));
				log.debug("pws: " + pws);
			}
			// retire states if we didn't see their concept during the loop above
			for (ProgramWorkflowState s : wf.getStates()) {
				if (!doneSoFar.contains(s.getConcept().getConceptId())) {
					s.setRetired(true);
				}
			}

			Context.getProgramWorkflowService().updateWorkflow(wf);
			view = getSuccessView();
			httpSession.setAttribute(WebConstants.OPENMRS_MSG_ATTR, "Workflow.saved");
		}

		return new ModelAndView(new RedirectView(view));
	}

}