/**
    * 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.lm.balancetransfer.validation;
  
  import java.math.BigDecimal;
  import java.sql.Date;
  import java.util.Calendar;
  import java.util.List;
  
  import org.apache.commons.lang.StringUtils;
  import org.apache.commons.lang.time.DateUtils;
  import org.kuali.hr.lm.accrual.AccrualCategory;
  import org.kuali.hr.lm.accrual.AccrualCategoryRule;
  import org.kuali.hr.lm.balancetransfer.BalanceTransfer;
  import org.kuali.hr.lm.employeeoverride.EmployeeOverride;
  import org.kuali.hr.time.principal.PrincipalHRAttributes;
  import org.kuali.hr.time.service.base.TkServiceLocator;
  import org.kuali.hr.time.util.TKContext;
  import org.kuali.hr.time.util.TKUser;
  import org.kuali.hr.time.util.TKUtils;
  import org.kuali.hr.time.util.TkConstants;
  import org.kuali.rice.kns.document.MaintenanceDocument;
  import org.kuali.rice.kns.maintenance.rules.MaintenanceDocumentRuleBase;
  import org.kuali.rice.krad.bo.PersistableBusinessObject;
  import org.kuali.rice.krad.util.GlobalVariables;
  import org.kuali.rice.krad.util.ObjectUtils;
  
  public class BalanceTransferValidation extends MaintenanceDocumentRuleBase {
  
  	//the "to" and "from" accrual categories should be in the supplied principal's leave plan as of the effective date.
  	private boolean validateLeavePlan(PrincipalHRAttributes pha,
  			AccrualCategory fromAccrualCategory, AccrualCategory toAccrualCategory, Date effectiveDate) {
  		boolean isValid = true;
  		
  		List<AccrualCategory> accrualCategories = TkServiceLocator.getAccrualCategoryService().getActiveAccrualCategoriesForLeavePlan(pha.getLeavePlan(), effectiveDate);
  		if(accrualCategories.size() > 0) {
  			boolean isFromInLeavePlan = false;
  			boolean isToInLeavePlan = false;
  			for(AccrualCategory activeAccrualCategory : accrualCategories) {
  				if(StringUtils.equals(activeAccrualCategory.getLmAccrualCategoryId(),fromAccrualCategory.getLmAccrualCategoryId())) {
  					isFromInLeavePlan = true;
  				}
  				if(StringUtils.equals(activeAccrualCategory.getLmAccrualCategoryId(), toAccrualCategory.getLmAccrualCategoryId())) {
  					isToInLeavePlan = true;
  				}
  			}
  			if(!isFromInLeavePlan) {
  				GlobalVariables.getMessageMap().putError("document.newMaintainableObject.fromAccrualCategory", "balanceTransfer.accrualCategory.notInLeavePlan", fromAccrualCategory.getAccrualCategory());
  				isValid &= false;
  			}
  			if(!isToInLeavePlan) {
  				GlobalVariables.getMessageMap().putError("document.newMaintainableObject.toAccrualCategory", "balanceTransfer.accrualCategory.notInLeavePlan", toAccrualCategory.getAccrualCategory());
  				isValid &= false;			
  			}
  		}
  		else {
  			GlobalVariables.getMessageMap().putError("document.newMaintainableObject.principalId", "balanceTransfer.principal.noACinLeavePlan");
  			isValid &=false;
  		}
  		return isValid;
  	}
  	
  	//See isTransferAmountUnderMaxLimit for futher validation
  	private boolean validateTransferAmount(BigDecimal transferAmount,
  			AccrualCategory debitedAccrualCategory,
  			AccrualCategory creditedAccrualCategory, String principalId, Date effectiveDate) {
  		
  		if(transferAmount.compareTo(BigDecimal.ZERO) < 0 ) {
  			GlobalVariables.getMessageMap().putError("document.newMaintainableObject.transferAmount", "balanceTransfer.amount.negative");
  			return false;
  		}
  
  		return true;
  	}
  
  	//Effective date not more than one year in advance
  	private boolean validateEffectiveDate(Date date) {
  		if(DateUtils.addYears(TKUtils.getCurrentDate(), 1).compareTo(date) > 0)
  			return true;
  		else
  			GlobalVariables.getMessageMap().putError("document.newMaintainableObject.effectiveDate", "balanceTransfer.effectiveDate.error");
  		return false;
  	}
  	
  	private boolean validateTransferFromAccrualCategory(AccrualCategory accrualCategory, String principalId,
  			Date effectiveDate, AccrualCategoryRule acr) {
 		//accrualCategory has rules
 		//PrincipalHRAttributes pha = TkServiceLocator.getPrincipalHRAttributeService().getPrincipalCalendar(principalId, effectiveDate);
 		
 		return true;
 	}
 	
 	//Transfer to accrual category should match the value defined in the accrual category rule
 	private boolean validateTransferToAccrualCategory(AccrualCategory accrualCategory, String principalId, Date effectiveDate, AccrualCategoryRule acr) {
 		AccrualCategory maxBalTranToAccCat = TkServiceLocator.getAccrualCategoryService().getAccrualCategory(acr.getMaxBalanceTransferToAccrualCategory(),effectiveDate);
 		if(!StringUtils.equals(maxBalTranToAccCat.getLmAccrualCategoryId(),accrualCategory.getLmAccrualCategoryId())) {
 			GlobalVariables.getMessageMap().putError("document.newMaintainableObject.toAccrualCategory", "balanceTransfer.toAccrualCategory.noMatch",accrualCategory.getAccrualCategory());
 			return false;
 		}
 		return true;
 	}
 
 	//no validation
 	private boolean validatePrincipal(PrincipalHRAttributes pha, String principalId) {
 		return true;
 	}
 	
 	//transfer amount must be under max limit when submitted via max balance triggered action or by a work area approver.
 	private boolean isTransferAmountUnderMaxLimit(String principalId, Date effectiveDate, String accrualCategory,
 			BigDecimal transferAmount, AccrualCategoryRule accrualRule, String leavePlan) {
 	
 		if(ObjectUtils.isNotNull(accrualRule)) {
 
 			BigDecimal maxTransferAmount = null;
 			if(ObjectUtils.isNotNull(accrualRule.getMaxTransferAmount())) {
 				maxTransferAmount = new BigDecimal(accrualRule.getMaxTransferAmount());
 			}
 			if(ObjectUtils.isNotNull(maxTransferAmount)) {
 				EmployeeOverride eo = TkServiceLocator.getEmployeeOverrideService().getEmployeeOverride(principalId, leavePlan, accrualCategory, TkConstants.EMPLOYEE_OVERRIDE_TYPE.get("MTA"), effectiveDate);
 				if(ObjectUtils.isNotNull(eo))
 					if(ObjectUtils.isNull(eo.getOverrideValue()))
 						maxTransferAmount = new BigDecimal(Long.MAX_VALUE);
 					else
 						maxTransferAmount = new BigDecimal(eo.getOverrideValue());
 				else {
 					BigDecimal fteSum = TkServiceLocator.getJobService().getFteSumForAllActiveLeaveEligibleJobs(principalId, effectiveDate);
 					maxTransferAmount = maxTransferAmount.multiply(fteSum);
 				}
 				if(transferAmount.compareTo(maxTransferAmount) > 0) {
 					GlobalVariables.getMessageMap().putError("document.newMaintainableObject.transferAmount","balanceTransfer.exceeds.transferLimit");
 					return false;
 				}
 			}
 		}
 		return true;
 	}
 	
 	@Override
 	public boolean processCustomRouteDocumentBusinessRules(MaintenanceDocument document) {
 		boolean isValid = super.processCustomRouteDocumentBusinessRules(document);
 		LOG.debug("entering custom validation for Balance Transfer");
 
 		PersistableBusinessObject pbo = (PersistableBusinessObject) this.getNewBo();
 
 		if(pbo instanceof BalanceTransfer) {
 
 			BalanceTransfer balanceTransfer = (BalanceTransfer) pbo;
 			
 			// if this balance transfer is on a system scheduled time off, then don't do further validation
 			if(StringUtils.isNotEmpty(balanceTransfer.getSstoId())) {
 				isValid &= BalanceTransferValidationUtils.validateSstoTranser(balanceTransfer);
 				return isValid;
 			}
 			if(isValid) {
 
 				/**
 				 * Validation is basically governed by accrual category rules. Get accrual category
 				 * rules for both the "To" and "From" accrual categories, pass to validators along with the
 				 * values needing to be validated.
 				 * 
 				 * Balance transfers initiated from the leave calendar display should already have all values
 				 * populated, thus validated, including the accrual category rule for the "From" accrual category.
 				 * 
 				 * Balance transfers initiated via the Maintenance tab will have no values populated.
 				 */
 				String principalId = balanceTransfer.getPrincipalId();
 				Date effectiveDate = balanceTransfer.getEffectiveDate();
 				String fromAccrualCategory = balanceTransfer.getFromAccrualCategory();
 				String toAccrualCategory = balanceTransfer.getToAccrualCategory();
 				AccrualCategory fromCat = TkServiceLocator.getAccrualCategoryService().getAccrualCategory(fromAccrualCategory, effectiveDate);
 				AccrualCategory toCat = TkServiceLocator.getAccrualCategoryService().getAccrualCategory(toAccrualCategory, effectiveDate);
 				PrincipalHRAttributes pha = TkServiceLocator.getPrincipalHRAttributeService().getPrincipalCalendar(principalId,effectiveDate);
 				
 				boolean isDeptAdmin = TKUser.isDepartmentAdmin();
 				boolean isSysAdmin = TKUser.isSystemAdmin();
 				if(isDeptAdmin || isSysAdmin) {
 					isValid &= validateTransferAmount(balanceTransfer.getTransferAmount(),fromCat,toCat, principalId, effectiveDate);
 				}
 				else {
 					if(ObjectUtils.isNotNull(pha)) {
 						if(ObjectUtils.isNotNull(pha.getLeavePlan())) {
 							AccrualCategoryRule acr = TkServiceLocator.getAccrualCategoryRuleService().getAccrualCategoryRuleForDate(fromCat,
 									effectiveDate, pha.getServiceDate());
 							if(ObjectUtils.isNotNull(acr)) {
 								if(StringUtils.isNotBlank(acr.getMaxBalFlag())
 										&& StringUtils.equals(acr.getMaxBalFlag(), "Y")) {
 									if(ObjectUtils.isNotNull(toCat)) {
 										
 										isValid &= validatePrincipal(pha,principalId);
 										isValid &= validateEffectiveDate(effectiveDate);
 										isValid &= validateLeavePlan(pha,fromCat,toCat,effectiveDate);
 										isValid &= validateTransferFromAccrualCategory(fromCat,principalId,effectiveDate,acr);
 										isValid &= validateTransferToAccrualCategory(toCat,principalId,effectiveDate,acr);
 										isValid &= validateTransferAmount(balanceTransfer.getTransferAmount(),fromCat,toCat, null, null);
 										isValid &= isTransferAmountUnderMaxLimit(principalId,effectiveDate,fromAccrualCategory,balanceTransfer.getTransferAmount(),acr,pha.getLeavePlan());
 									}
 									else {
 										//should never be the case if accrual category rules are validated correctly.
 										GlobalVariables.getMessageMap().putError("document.newMaintainableObject.fromAccrualCategory",
 												"balanceTransfer.fromAccrualCategory.rules.transferToAccrualCategory",
 												fromAccrualCategory);
 										isValid &= false;
 									}
 								}
 								else {
 									//max bal flag null, blank, empty, or "N"
 									GlobalVariables.getMessageMap().putError("document.newMaintinableObject.fromAccrualCategory",
 											"balanceTransfer.fromAccrualCategory.rules.maxBalFlag", fromAccrualCategory);
 									isValid &= false;
 								}
 							}
 							else {
 								//department admins must validate amount to transfer does not exceed current balance.
 								GlobalVariables.getMessageMap().putError("document.newMaintainableObject.fromAccrualCategory",
 										"balanceTransfer.fromAccrualCategory.rules.exist",fromCat.getAccrualCategory());
 								isValid &= false;
 							}
 						}
 						else {
 							//if the principal doesn't have a leave plan, there aren't any accrual categories that can be debited/credited.
 							GlobalVariables.getMessageMap().putError("document.newMaintainableObject.principalId","balanceTransfer.principal.noLeavePlan");
 							isValid &=false;
 						}
 					}
 					else  {
 						//if the principal has no principal hr attributes, they're not a principal.
 						GlobalVariables.getMessageMap().putError("document.newMaintainableObject.principalId","balanceTransfer.principal.noAttributes");
 						isValid &= false;
 					}
 				}
 			}
 		}
 		return isValid; 
 	}
 }