/**
    * Copyright 2004-2013 The Kuali Foundation
    *
    * Licensed under the Educational Community License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.opensource.org/licenses/ecl2.php
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.kuali.hr.time.timesummary.service;
  
  import org.apache.commons.lang.StringUtils;
  import org.joda.time.DateTimeFieldType;
  import org.joda.time.LocalDateTime;
  import org.kuali.hr.job.Job;
  import org.kuali.hr.time.assignment.Assignment;
  import org.kuali.hr.time.assignment.AssignmentDescriptionKey;
  import org.kuali.hr.time.calendar.Calendar;
  import org.kuali.hr.time.calendar.CalendarEntries;
  import org.kuali.hr.time.earncode.EarnCode;
  import org.kuali.hr.time.earngroup.EarnGroup;
  import org.kuali.hr.time.flsa.FlsaDay;
  import org.kuali.hr.time.flsa.FlsaWeek;
  import org.kuali.hr.time.service.base.TkServiceLocator;
  import org.kuali.hr.time.timeblock.TimeBlock;
  import org.kuali.hr.time.timeblock.TimeHourDetail;
  import org.kuali.hr.time.timesheet.TimesheetDocument;
  import org.kuali.hr.time.timesummary.AssignmentRow;
  import org.kuali.hr.time.timesummary.EarnCodeSection;
  import org.kuali.hr.time.timesummary.EarnGroupSection;
  import org.kuali.hr.time.timesummary.TimeSummary;
  import org.kuali.hr.time.util.TKUtils;
  import org.kuali.hr.time.util.TkConstants;
  import org.kuali.hr.time.util.TkTimeBlockAggregate;
  import org.kuali.hr.time.workarea.WorkArea;
  
  import java.math.BigDecimal;
  import java.util.*;
  
  public class TimeSummaryServiceImpl implements TimeSummaryService {
  	private static final String OTHER_EARN_GROUP = "Other";
  
      @Override
  	public TimeSummary getTimeSummary(TimesheetDocument timesheetDocument) {
  		TimeSummary timeSummary = new TimeSummary();
  
  		if(timesheetDocument.getTimeBlocks() == null) {
  			return timeSummary;
  		}
  
          List<Boolean> dayArrangements = new ArrayList<Boolean>();
  
  		timeSummary.setSummaryHeader(getHeaderForSummary(timesheetDocument.getPayCalendarEntry(), dayArrangements));
  		TkTimeBlockAggregate tkTimeBlockAggregate = new TkTimeBlockAggregate(timesheetDocument.getTimeBlocks(), timesheetDocument.getPayCalendarEntry(), TkServiceLocator.getCalendarService().getCalendar(timesheetDocument.getPayCalendarEntry().getHrCalendarId()), true);
  		timeSummary.setWorkedHours(getWorkedHours(tkTimeBlockAggregate));
  
          List<EarnGroupSection> earnGroupSections = getEarnGroupSections(tkTimeBlockAggregate, timeSummary.getSummaryHeader().size()+1, 
          			dayArrangements, timesheetDocument.getAsOfDate(), timesheetDocument.getDocEndDate());
          timeSummary.setSections(earnGroupSections);
  
  		return timeSummary;
  	}
  	
      /**
       * Aggregates timeblocks into the appropriate earngroup-> earncode -> assignment rows
       * @param tkTimeBlockAggregate
       * @param numEntries
       * @param dayArrangements
       * @param asOfDate
       * @return
       */
  	public List<EarnGroupSection> getEarnGroupSections(TkTimeBlockAggregate tkTimeBlockAggregate, int numEntries, List<Boolean> dayArrangements, Date asOfDate , Date docEndDate){
  		List<EarnGroupSection> earnGroupSections = new ArrayList<EarnGroupSection>();
  		List<FlsaWeek> flsaWeeks = tkTimeBlockAggregate.getFlsaWeeks(TkServiceLocator.getTimezoneService().getUserTimezoneWithFallback());
  		Map<String, EarnCodeSection> earnCodeToEarnCodeSection = new HashMap<String, EarnCodeSection>();
  		Map<String, EarnGroupSection> earnGroupToEarnGroupSection = new HashMap<String, EarnGroupSection>();
  		
  		int dayCount = 0;
  		
  		//TODO remove this and correct the aggregate .. not sure what the down stream changes are
  		//so leaving this for initial release
  		List<FlsaWeek> trimmedFlsaWeeks = new ArrayList<FlsaWeek>();
  		for(FlsaWeek flsaWeek : flsaWeeks){
  			if(flsaWeek.getFlsaDays().size() > 0){
  				trimmedFlsaWeeks.add(flsaWeek);
  			}
  		}
  		
  		//For every flsa week and day aggegate each time hour detail 
  		// buckets it by earn code section first
  		for(FlsaWeek flsaWeek : trimmedFlsaWeeks){
  			int weekSize = 0;
  			List<FlsaDay> flsaDays = flsaWeek.getFlsaDays();
 			for(FlsaDay flsaDay : flsaDays){
 				Map<String, List<TimeBlock>> earnCodeToTimeBlocks = flsaDay.getEarnCodeToTimeBlocks();
 				
 				for(String earnCode : earnCodeToTimeBlocks.keySet()){
 					for(TimeBlock timeBlock : earnCodeToTimeBlocks.get(earnCode)){
 						for(TimeHourDetail thd : timeBlock.getTimeHourDetails()){
 							if(StringUtils.equals(TkConstants.LUNCH_EARN_CODE, thd.getEarnCode())){
 								continue;
 							}
 							EarnCodeSection earnCodeSection = earnCodeToEarnCodeSection.get(thd.getEarnCode());
 							if(earnCodeSection == null){
 								earnCodeSection = new EarnCodeSection();
 								earnCodeSection.setEarnCode(thd.getEarnCode());
 								EarnCode earnCodeObj = TkServiceLocator.getEarnCodeService().getEarnCode(thd.getEarnCode(), TKUtils.getTimelessDate(asOfDate));
 								earnCodeSection.setDescription(earnCodeObj.getDescription());
 								earnCodeSection.setIsAmountEarnCode((earnCodeObj.getRecordMethod()!= null && earnCodeObj.getRecordMethod().equalsIgnoreCase(TkConstants.EARN_CODE_AMOUNT)) ? true : false);
 								for(int i = 0;i<(numEntries-1);i++){
 									earnCodeSection.getTotals().add(BigDecimal.ZERO);
 								}
 								
 								earnCodeToEarnCodeSection.put(thd.getEarnCode(), earnCodeSection);
 							}
 							String assignKey = timeBlock.getAssignmentKey();
 							AssignmentRow assignRow = earnCodeSection.getAssignKeyToAssignmentRowMap().get(assignKey);
 							if(assignRow == null){
 								assignRow = new AssignmentRow();
 								assignRow.setAssignmentKey(assignKey);
 								AssignmentDescriptionKey assignmentKey = TkServiceLocator.getAssignmentService().getAssignmentDescriptionKey(assignKey);
 								Assignment assignment = TkServiceLocator.getAssignmentService().getAssignment(timeBlock.getPrincipalId(), assignmentKey, TKUtils.getTimelessDate(asOfDate));
 								// some assignment may not be effective at the beginning of the pay period, use the end date of the period to find it
 								if(assignment == null) {
 									assignment = TkServiceLocator.getAssignmentService().getAssignment(timeBlock.getPrincipalId(), assignmentKey, TKUtils.getTimelessDate(docEndDate));
 								}
 								//TODO push this up to the assignment fetch/fully populated instead of like this
 								if(assignment != null){
 									if(assignment.getJob() == null){
 										Job aJob = TkServiceLocator.getJobService().getJob(assignment.getPrincipalId(),assignment.getJobNumber(),TKUtils.getTimelessDate(assignment.getEffectiveDate()));
 										assignment.setJob(aJob);
 									}
 									if(assignment.getWorkAreaObj() == null){
 										WorkArea aWorkArea = TkServiceLocator.getWorkAreaService().getWorkArea(assignment.getWorkArea(), TKUtils.getTimelessDate(assignment.getEffectiveDate()));
 										assignment.setWorkAreaObj(aWorkArea);
 									}
 									assignRow.setDescr(assignment.getAssignmentDescription());
 								}
 								for(int i = 0;i<(numEntries-1);i++){
 									assignRow.getTotal().add(BigDecimal.ZERO);
 									assignRow.getAmount().add(BigDecimal.ZERO);
 								}
 								assignRow.setEarnCodeSection(earnCodeSection);
 								earnCodeSection.addAssignmentRow(assignRow);
 							}
 							assignRow.addToTotal(dayCount, thd.getHours());
 							assignRow.addToAmount(dayCount, thd.getAmount());
 						}
 					}
 				}
 				dayCount++;
 				weekSize++;
 			}
 			//end of flsa week accumulate weekly totals
 			for(EarnCodeSection earnCodeSection : earnCodeToEarnCodeSection.values()){
 				earnCodeSection.addWeeklyTotal(dayCount, weekSize);
 			}			
 			weekSize = 0;
 
 			dayCount++;
 		}
 		
 		dayCount = 0;
 		//now create all teh earn group sections and aggregate accordingly
 		for(EarnCodeSection earnCodeSection : earnCodeToEarnCodeSection.values()){
 			String earnCode = earnCodeSection.getEarnCode();
             EarnGroup earnGroupObj = TkServiceLocator.getEarnGroupService().getEarnGroupSummaryForEarnCode(earnCode, TKUtils.getTimelessDate(asOfDate));
 			String earnGroup = null;
 			if(earnGroupObj == null){
 				earnGroup = OTHER_EARN_GROUP;
 			} else{
 				earnGroup = earnGroupObj.getDescr();
 			}
 			
 			EarnGroupSection earnGroupSection = earnGroupToEarnGroupSection.get(earnGroup);
 			if(earnGroupSection == null){
 				earnGroupSection = new EarnGroupSection();
 				earnGroupSection.setEarnGroup(earnGroup);
 				for(int i =0;i<(numEntries-1);i++){
 					earnGroupSection.getTotals().add(BigDecimal.ZERO);
 				}
 				earnGroupToEarnGroupSection.put(earnGroup, earnGroupSection);
 			}
 			earnGroupSection.addEarnCodeSection(earnCodeSection, dayArrangements);
 			
 		}
 		for(EarnGroupSection earnGroupSection : earnGroupToEarnGroupSection.values()){
 			earnGroupSections.add(earnGroupSection);
 		}
 		return earnGroupSections;
 	}
 	
 	/**
 	 * Generate a list of string describing this pay calendar entry for the summary
 	 * @param payCalEntry
 	 * @return
 	 */
 	protected List<String> getSummaryHeader(CalendarEntries payCalEntry){
 		List<String> summaryHeader = new ArrayList<String>();
 		int dayCount = 0;
 		Date beginDateTime = payCalEntry.getBeginPeriodDateTime();
 		Date endDateTime = payCalEntry.getEndPeriodDateTime();
 		boolean virtualDays = false;
         LocalDateTime endDate = payCalEntry.getEndLocalDateTime();
 
         if (endDate.get(DateTimeFieldType.hourOfDay()) != 0 || endDate.get(DateTimeFieldType.minuteOfHour()) != 0 ||
                 endDate.get(DateTimeFieldType.secondOfMinute()) != 0){
             virtualDays = true;
         }
 		
 		Date currDateTime = beginDateTime;
 		java.util.Calendar cal = GregorianCalendar.getInstance();
 		
 		while(currDateTime.before(endDateTime)){
 			LocalDateTime currDate = new LocalDateTime(currDateTime);
 			summaryHeader.add(makeHeaderDiplayString(currDate, virtualDays));
 			
 			dayCount++;
 			if((dayCount % 7) == 0){
 				summaryHeader.add("Week "+ ((dayCount / 7)));
 			}
 			cal.setTime(currDateTime);
 			cal.add(java.util.Calendar.HOUR, 24);
 			currDateTime = cal.getTime();
 		}
 		
 		summaryHeader.add("Period Total");
 		return summaryHeader;
 	}
 
     /**
      * Provides the number of hours worked for the pay period indicated in the
      * aggregate.
      *
      * @param aggregate The aggregate we are summing
      *
      * @return A list of BigDecimals containing the number of hours worked.
      * This list will line up with the header.
      */
     private List<BigDecimal> getWorkedHours(TkTimeBlockAggregate aggregate) {
         List<BigDecimal> hours = new ArrayList<BigDecimal>();
         BigDecimal periodTotal = TkConstants.BIG_DECIMAL_SCALED_ZERO;
         for (FlsaWeek week : aggregate.getFlsaWeeks(TkServiceLocator.getTimezoneService().getUserTimezoneWithFallback())) {
             BigDecimal weeklyTotal = TkConstants.BIG_DECIMAL_SCALED_ZERO;
             for (FlsaDay day : week.getFlsaDays()) {
                 BigDecimal totalForDay = TkConstants.BIG_DECIMAL_SCALED_ZERO;
                 for (TimeBlock block : day.getAppliedTimeBlocks()) {
                     totalForDay = totalForDay.add(block.getHours(), TkConstants.MATH_CONTEXT);
                     weeklyTotal = weeklyTotal.add(block.getHours(), TkConstants.MATH_CONTEXT);
                     periodTotal = periodTotal.add(block.getHours(), TkConstants.MATH_CONTEXT);
                 }
                 hours.add(totalForDay);
             }
             hours.add(weeklyTotal);
         }
         hours.add(periodTotal);
 
         return hours;
     }
 
 
     /**
      * Handles the generation of the display header for the time summary.
      *
      * @param cal The PayCalendarEntries object we are using to derive information.
      * @param dayArrangements Container passed in to store the position of week / period aggregate sums
      *
      * @return An in-order string of days for this period that properly accounts
      * for FLSA week boundaries in the pay period.
      */
     @Override
     public List<String> getHeaderForSummary(CalendarEntries cal, List<Boolean> dayArrangements) {
         List<String> header = new ArrayList<String>();
 
         // Maps directly to joda time day of week constants.
         int flsaBeginDay = this.getPayCalendarForEntry(cal).getFlsaBeginDayConstant();
         boolean virtualDays = false;
         LocalDateTime startDate = cal.getBeginLocalDateTime();
         LocalDateTime endDate = cal.getEndLocalDateTime();
 
         // Increment end date if we are on a virtual day calendar, so that the
         // for loop can account for having the proper amount of days on the
         // summary calendar.
         if (endDate.get(DateTimeFieldType.hourOfDay()) != 0 || endDate.get(DateTimeFieldType.minuteOfHour()) != 0 ||
                 endDate.get(DateTimeFieldType.secondOfMinute()) != 0)
         {
             endDate = endDate.plusDays(1);
             virtualDays = true;
         }
 
         boolean afterFirstDay = false;
         int week = 1;
         for (LocalDateTime currentDate = startDate; currentDate.compareTo(endDate) < 0; currentDate = currentDate.plusDays(1)) {
 
             if (currentDate.getDayOfWeek() == flsaBeginDay && afterFirstDay) {
                 header.add("Week " + week);
                 dayArrangements.add(false);
                 week++;
             }
 
             header.add(makeHeaderDiplayString(currentDate, virtualDays));
             dayArrangements.add(true);
 
 
             afterFirstDay = true;
         }
 
         // We may have a very small final "week" on this pay period. For now
         // we will mark it as a week, and if someone doesn't like it, it can
         // be removed.
         if (!header.get(header.size()-1).startsWith("Week")) {
             dayArrangements.add(false);
             header.add("Week " + week);
         }
 
 
         header.add("Period Total");
         dayArrangements.add(false);
         return header;
     }
 
     /**
      * Helper function to generate display text for the summary header.
      * @param currentDate The date we are generating for.
      * @param virtualDays Whether or not virtual days apply.
      * @return A string appropriate for UI display.
      */
     private String makeHeaderDiplayString(LocalDateTime currentDate, boolean virtualDays) {
         StringBuilder display = new StringBuilder();
         
         display.append(currentDate.toString("E"));
         if (virtualDays) {
         	LocalDateTime nextDate = currentDate.plusDays(1);
         	display.append(" - ");
             display.append(nextDate.toString("E"));
         }
         
         display.append("<br />");
         
         display.append(currentDate.toString(TkConstants.DT_ABBREV_DATE_FORMAT));
         if (virtualDays) {
             LocalDateTime nextDate = currentDate.plusDays(1);
             display.append(" - ");
             display.append(nextDate.toString(TkConstants.DT_ABBREV_DATE_FORMAT));
         }
 
         return display.toString();
     }
 
     /**
      * @param calEntry Calendar entry we are using for lookup.
      * @return The PayCalendar that owns the provided entry.
      */
     private Calendar getPayCalendarForEntry(CalendarEntries calEntry) {
         Calendar cal = null;
 
         if (calEntry != null) {
             cal = TkServiceLocator.getCalendarService().getCalendar(calEntry.getHrCalendarId());
         }
 
         return cal;
     }
 
 }