/**

  * Copyright 2010 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.osedu.org/licenses/ECL-2.0 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.student.core.assembly.dictionary;

 import java.lang.ref.SoftReference;

 import java.text.DateFormat;

 import java.text.ParseException;

 import java.text.SimpleDateFormat;

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import java.util.concurrent.ConcurrentHashMap;

 import org.apache.log4j.Logger;

 import org.kuali.student.core.assembly.data.ConstraintMetadata;

 import org.kuali.student.core.assembly.data.Data;

 import org.kuali.student.core.assembly.data.LookupMetadata;

 import org.kuali.student.core.assembly.data.LookupParamMetadata;

 import org.kuali.student.core.assembly.data.Metadata;

 import org.kuali.student.core.assembly.data.UILookupConfig;

 import org.kuali.student.core.assembly.data.UILookupData;

 import org.kuali.student.core.assembly.data.Data.DataType;

 import org.kuali.student.core.assembly.data.Data.Value;

 import org.kuali.student.core.assembly.data.Metadata.WriteAccess;

 import org.kuali.student.core.dictionary.dto.CaseConstraint;

 import org.kuali.student.core.dictionary.dto.CommonLookupParam;

 import org.kuali.student.core.dictionary.dto.Constraint;

 import org.kuali.student.core.dictionary.dto.FieldDefinition;

 import org.kuali.student.core.dictionary.dto.ObjectStructureDefinition;

 import org.kuali.student.core.dictionary.dto.WhenConstraint;

 import org.kuali.student.core.dictionary.service.DictionaryService;

 import org.kuali.student.core.dto.DtoConstants.DtoState;

 import org.springframework.beans.BeanUtils;

 import org.springframework.context.ApplicationContext;

 import org.springframework.context.support.ClassPathXmlApplicationContext;

 /**

  * This class provides metadata lookup for service dto objects.

  * 

  * @author Kuali Student Team

  */

 public class MetadataServiceImpl {

     final Logger LOG = Logger.getLogger(MetadataServiceImpl.class);

     private Map<String, DictionaryService> dictionaryServiceMap;

     private List<UILookupConfig> lookupObjectStructures;

     private String uiLookupContext;

     private static class RecursionCounter {

         public static final int MAX_DEPTH = 4;

         private Map<String, Integer> recursions = new HashMap<String, Integer>();

         public int increment(String objectName) {

             Integer hits = recursions.get(objectName);

             if (hits == null) {

                 hits = new Integer(1);

             } else {

                 hits++;

             }

             recursions.put(objectName, hits);

             return hits;

         }

         public int decrement(String objectName) {

             Integer hits = recursions.get(objectName);

             if (hits >= 1) {

                 hits--;

             }

             recursions.put(objectName, hits);

             return hits;

         }

     }

     /**

      * Create a metadata service initializing it with all known dictionary services

      * 

      * @param dictionaryServices

      */

     public MetadataServiceImpl(DictionaryService... dictionaryServices) {

         if (dictionaryServices != null) {

             this.dictionaryServiceMap = new HashMap<String, DictionaryService>();

             for (DictionaryService d : dictionaryServices) {

                 List<String> objectTypes = d.getObjectTypes();

                 for (String objectType : objectTypes) {

                     dictionaryServiceMap.put(objectType, d);

                 }

             }

         }

     }

     /**

      * This method gets the metadata for the given object key, type, state and nextState

      * 

      * @param objectKey

      * @param type The type of the object (value can be null)

      * @param state The state for which to retrieve object constraints (value can be null)

      * @param nextState The state to to check requiredForNextState indicators (value can be null)

      * @return

      */

     public Metadata getMetadata(String objectKey, String type, String state, String nextState) {

             return getMetadataFromDictionaryService(objectKey, type, state, nextState);

     }

     /**

      * This method gets the metadata for the given object key, type and state

      * 

      * @param objectKey

      * @param type The type of the object (value can be null)

      * @param state The state for which to retrieve object constraints (value can be null)

      * @return

      */

     public Metadata getMetadata(String objectKey, String type, String state) {

         return getMetadata(objectKey, type, state, null);

     }

     /**

      * This method gets the metadata for the given object key and state

      * 

      * @param objectKey

      * @param type The type of the object (value can be null)

      */

     public Metadata getMetadata(String objectKey, String state) {

         return getMetadata(objectKey, null, state);

     }

     /**

      * This method gets the metadata for the given object key for state DRAFT.

      * 

      * @see MetadataServiceImpl#getMetadata(String, String)

      * @param objectKey

      * @return

      */

     public Metadata getMetadata(String objectKey) {

         return getMetadata(objectKey, null, null);

     }

     /**

      * This invokes the appropriate dictionary service to get the object structure and then converts it to a metadata

      * structure.

      * 

      * @param objectKey

      * @param type

      * @param state

      * @return

      */

     protected Metadata getMetadataFromDictionaryService(String objectKey, String type, String state, String nextState) {

         Metadata metadata = new Metadata();

         ObjectStructureDefinition objectStructure = getObjectStructure(objectKey);

         metadata.setProperties(getProperties(objectStructure, type, state, nextState, new RecursionCounter()));

         metadata.setWriteAccess(WriteAccess.ALWAYS);

         metadata.setDataType(DataType.DATA);

         addLookupstoMetadata(objectKey, metadata, type);

         return metadata;

     }

     /**

      * This method is used to convert a list of dictionary fields into metadata properties

      * 

      * @param fields

      * @param type

      * @param state

      * @return

      */

     private Map<String, Metadata> getProperties(ObjectStructureDefinition objectStructure, String type, String state, String nextState, RecursionCounter counter) {

         String objectId = objectStructure.getName();

         int hits = counter.increment(objectId);

         Map<String, Metadata> properties = null;

         if (hits < RecursionCounter.MAX_DEPTH) {

             properties = new HashMap<String, Metadata>();

             List<FieldDefinition> attributes = objectStructure.getAttributes();

             for (FieldDefinition fd : attributes) {

                 Metadata metadata = new Metadata();

                 // Set constraints, authz flags, default value

                 metadata.setWriteAccess(WriteAccess.ALWAYS);

                 metadata.setDataType(convertDictionaryDataType(fd.getDataType()));

                 metadata.setConstraints(getConstraints(fd, type, state, nextState));

                 metadata.setCanEdit(!fd.isReadOnly());

                 metadata.setCanUnmask(!fd.isMask());

                 metadata.setCanView(!fd.isHide());

                 metadata.setDynamic(fd.isDynamic());

                 metadata.setLabelKey(fd.getLabelKey());

                 metadata.setDefaultValue(convertDefaultValue(metadata.getDataType(), fd.getDefaultValue()));

                            if (fd.isPartialMask()){

                                    metadata.setPartialMaskFormatter(fd.getPartialMaskFormatter());

                            }

                            if (fd.isMask()){

                                    metadata.setMaskFormatter(fd.getMaskFormatter());

                            }

                 // Get properties for nested object structure

                 Map<String, Metadata> nestedProperties = null;

                 if (fd.getDataType() == org.kuali.student.core.dictionary.dto.DataType.COMPLEX && fd.getDataObjectStructure() != null) {

                     nestedProperties = getProperties(fd.getDataObjectStructure(), type, state, nextState, counter);

                 }

                 // For repeating field, create a LIST with wildcard in metadata structure

                 if (isRepeating(fd)) {

                     Metadata repeatingMetadata = new Metadata();

                     metadata.setDataType(DataType.LIST);

                     repeatingMetadata.setWriteAccess(WriteAccess.ALWAYS);

                     repeatingMetadata.setOnChangeRefreshMetadata(false);

                     repeatingMetadata.setDataType(convertDictionaryDataType(fd.getDataType()));

                     if (nestedProperties != null) {

                         repeatingMetadata.setProperties(nestedProperties);

                     }

                     Map<String, Metadata> repeatingProperty = new HashMap<String, Metadata>();

                     repeatingProperty.put("*", repeatingMetadata);

                     metadata.setProperties(repeatingProperty);

                 } else if (nestedProperties != null) {

                     metadata.setProperties(nestedProperties);

                 }

                 properties.put(fd.getName(), metadata);

             }

         }

         counter.decrement(objectId);

         return properties;

     }

     /**

      * This method determines if a field is repeating

      * 

      * @param fd

      * @return

      */

     protected boolean isRepeating(FieldDefinition fd) {

         boolean isRepeating = false;

         try {

             int maxOccurs = Integer.parseInt(fd.getMaxOccurs());

             isRepeating = maxOccurs > 1;

         } catch (NumberFormatException nfe) {

             isRepeating = FieldDefinition.UNBOUNDED.equals(fd.getMaxOccurs());

         }

         return isRepeating;

     }

     /**

      * This method gets the object structure for given objectKey from a dictionaryService

      * 

      * @param objectKey

      * @return

      */

     protected ObjectStructureDefinition getObjectStructure(String objectKey) {

         DictionaryService dictionaryService = dictionaryServiceMap.get(objectKey);

         if (dictionaryService == null) {

             throw new RuntimeException("Dictionary service not provided for objectKey=[" + objectKey + "].");

         }

         return dictionaryService.getObjectStructure(objectKey);

     }

     protected List<ConstraintMetadata> getConstraints(FieldDefinition fd, String type, String state, String nextState) {

         List<ConstraintMetadata> constraints = new ArrayList<ConstraintMetadata>();

         ConstraintMetadata constraintMetadata = new ConstraintMetadata();

         updateConstraintMetadata(constraintMetadata, (Constraint) fd, type, state, nextState);

         constraints.add(constraintMetadata);

         return constraints;

     }

     /**

      * This updates the constraintMetadata with defintions from the dictionary constraint field.

      * 

      * @param constraintMetadata

      * @param constraint

      */

     protected void updateConstraintMetadata(ConstraintMetadata constraintMetadata, Constraint constraint, String type, String state, String nextState) {

         // For now ignoring the serverSide flag and making determination of which constraints

         // should be passed up to the UI via metadata.

         // Min Length

         if (constraint.getMinLength() != null) {

             constraintMetadata.setMinLength(constraint.getMinLength());

         }

         // Max Length

         try {

             if (constraint.getMaxLength() != null) {

                 constraintMetadata.setMaxLength(Integer.parseInt(constraint.getMaxLength()));

             }

             // Do we need to add another constraint and label it required if minOccurs = 1

         } catch (NumberFormatException nfe) {

             // Ignoring an unbounded length, cannot be handled in metadata structure, maybe change Metadata to string or set

             // to -1

             constraintMetadata.setMaxLength(9999);

         }

         // Min Occurs

         if (constraint.getMinOccurs() != null) {

             constraintMetadata.setMinOccurs(constraint.getMinOccurs());

         }

         // Max Occurs

         String maxOccurs = constraint.getMaxOccurs();

         if (maxOccurs != null) {

             try {

                 constraintMetadata.setMaxOccurs(Integer.parseInt(maxOccurs));

                 if (!FieldDefinition.SINGLE.equals(maxOccurs)) {

                     constraintMetadata.setId("repeating");

                 }

             } catch (NumberFormatException nfe) {

                 // Setting unbounded to a value of 9999, since unbounded not handled by metadata

                 if (FieldDefinition.UNBOUNDED.equals(maxOccurs)) {

                     constraintMetadata.setId("repeating");

                     constraintMetadata.setMaxOccurs(9999);

                 }

             }

         }

         // Min Value

         if (constraint.getExclusiveMin() != null) {

             constraintMetadata.setMinValue(constraint.getExclusiveMin());

         }

         // Max Value

         if (constraint.getInclusiveMax() != null) {

             constraintMetadata.setMaxValue(constraint.getInclusiveMax());

         }

         if (constraint.getValidChars() != null) {

             constraintMetadata.setValidChars(constraint.getValidChars().getValue());

             constraintMetadata.setValidCharsMessageId(constraint.getValidChars().getLabelKey());

         }

         // Case constraints

         if (constraint.getCaseConstraint() != null) {

             processCaseConstraint(constraintMetadata, constraint.getCaseConstraint(), type, state, nextState);

         }

     }

     protected void processCaseConstraint(ConstraintMetadata constraintMetadata, CaseConstraint caseConstraint, String type, String state, String nextState) {

         String fieldPath = caseConstraint.getFieldPath();

         List<WhenConstraint> whenConstraints = caseConstraint.getWhenConstraint();

         fieldPath = (fieldPath != null ? fieldPath.toUpperCase() : fieldPath);

         if ("STATE".equals(fieldPath)) {

             // Process a state constraint

                 // Defaults for state and nextState

                 state = (state == null ? DtoState.DRAFT.toString():state);

                 nextState = (nextState == null ? DtoState.getNextStateAsString(state):nextState);

             if ("EQUALS".equals(caseConstraint.getOperator()) && whenConstraints != null) {

                 for (WhenConstraint whenConstraint : whenConstraints) {

                     List<Object> values = whenConstraint.getValues();

                     if (values != null) {

                         Constraint constraint = whenConstraint.getConstraint();

                         // Set the required for next state flag

                         if (values.contains(nextState)) {

                             if (constraint.getMinOccurs() > 0) {

                                 constraintMetadata.setRequiredForNextState(true);

                                 constraintMetadata.setNextState(nextState);

                             }

                         }

                         // Update constraints based on state constraints

                         if (values.contains(state.toUpperCase())) {

                             updateConstraintMetadata(constraintMetadata, constraint, type, state, nextState);

                         }

                     }

                 }

             }

         } else if ("TYPE".equals(fieldPath)) {

             // Process a type constraint

             if ("EQUALS".equals(caseConstraint.getOperator()) && whenConstraints != null) {

                 for (WhenConstraint whenConstraint : whenConstraints) {

                     List<Object> values = whenConstraint.getValues();

                     if (values != null && values.contains(type)) {

                         Constraint constraint = whenConstraint.getConstraint();

                         updateConstraintMetadata(constraintMetadata, constraint, type, state, nextState);

                     }

                 }

             }

         }

     }

     /**

      * Convert Object value to respective DataType. Method return null for object Value.

      * 

      * @param dataType

      * @param value

      * @return

      */

     protected Value convertDefaultValue(DataType dataType, Object value) {

         Value v = null;

         if (value instanceof String) {

             String s = (String) value;

             switch (dataType) {

                 case STRING:

                     v = new Data.StringValue(s);

                     break;

                 case BOOLEAN:

                     v = new Data.BooleanValue(Boolean.valueOf(s));

                     break;

                 case FLOAT:

                     v = new Data.FloatValue(Float.valueOf(s));

                     break;

                 case DATE:

                     DateFormat format = new SimpleDateFormat("yyyy-MM-dd");

                     try {

                         v = new Data.DateValue(format.parse(s));

                     } catch (ParseException e) {

                         LOG.error("Unable to get default date value from metadata definition");

                     }

                     break;

                 case LONG:

                     if (!s.isEmpty()) {

                         v = new Data.LongValue(Long.valueOf(s));

                     }

                     break;

                 case DOUBLE:

                     v = new Data.DoubleValue(Double.valueOf(s));

                     break;

                 case INTEGER:

                     v = new Data.IntegerValue(Integer.valueOf(s));

                     break;

             }

         } else {

             v = convertDefaultValue(value);

         }

         return v;

     }

     protected Value convertDefaultValue(Object value) {

         Value v = null;

         if (value instanceof String) {

             v = new Data.StringValue((String) value);

         } else if (value instanceof Boolean) {

             v = new Data.BooleanValue((Boolean) value);

         } else if (value instanceof Integer) {

             v = new Data.IntegerValue((Integer) value);

         } else if (value instanceof Double) {

             v = new Data.DoubleValue((Double) value);

         } else if (value instanceof Long) {

             v = new Data.LongValue((Long) value);

         } else if (value instanceof Short) {

             v = new Data.ShortValue((Short) value);

         } else if (value instanceof Float) {

             v = new Data.FloatValue((Float) value);

         }

         return v;

     }

     protected DataType convertDictionaryDataType(org.kuali.student.core.dictionary.dto.DataType dataType) {

         switch (dataType) {

             case STRING:

                 return DataType.STRING;

             case BOOLEAN:

                 return DataType.BOOLEAN;

             case INTEGER:

                 return DataType.INTEGER;

             case FLOAT:

                 return DataType.FLOAT;

             case COMPLEX:

                 return DataType.DATA;

             case DATE:

                 return DataType.DATE;

             case DOUBLE:

                 return DataType.DOUBLE;

             case LONG:

                 return DataType.LONG;

         }

         return null;

     }

     public void setUiLookupContext(String uiLookupContext) {

         this.uiLookupContext = uiLookupContext;

         init();

     }

     @SuppressWarnings("unchecked")

     private void init() {

         ApplicationContext ac = new ClassPathXmlApplicationContext(uiLookupContext);

         Map<String, UILookupConfig> beansOfType = (Map<String, UILookupConfig>) ac.getBeansOfType(UILookupConfig.class);

         lookupObjectStructures = new ArrayList<UILookupConfig>();

         for (UILookupConfig objStr : beansOfType.values()) {

             lookupObjectStructures.add(objStr);

         }

         System.out.println("UILookup loaded");

     }

     private String calcSimpleName(String objectKey) {

         int lastDot = objectKey.lastIndexOf(".");

         if (lastDot == -1) {

             return objectKey;

         }

         return objectKey.substring(lastDot + 1);

     }

     private boolean matchesObjectKey(String objectKey, String path) {

         String simpleName = calcSimpleName(objectKey);

         if (path.toLowerCase().startsWith(simpleName.toLowerCase())) {

             // System.out.println ("matchesObjectKey: is TRUE for " + objectKey + " and " + path);

             return true;

         }

         // System.out.println ("matchesObjectKey: is FALSE for " + objectKey + " and " + path);

         return false;

     }

     private boolean matchesType(String paramType, String lookupType) {

         // both null

         if (paramType == null && lookupType == null) {

             return true;

         }

         // not asking for type specific but the lookup defnition is type specific then

         // no match

         if (paramType == null && lookupType != null) {

             return false;

         }

         // if looking for type specific but the lookup is not specific then

         // take as default

         // If configuration has both a null type (i.e. default) AND has a type

         // specific one the type specific one has to be entered into the configuration

         // file first so it is found first

         if (paramType != null && lookupType == null) {

             return true;

         }

         if (paramType.equalsIgnoreCase(lookupType)) {

             // System.out.println ("matchesType: is TRUE for " + paramType + " and " + lookupType);

             return true;

         }

         // System.out.println ("matchesType: is FALSE for " + paramType + " and " + lookupType);

         return false;

     }

     private void addLookupstoMetadata(String objectKey, Metadata metadata, String type) {

         if (lookupObjectStructures != null) {

             for (UILookupConfig lookup : lookupObjectStructures) {

                 if (!matchesObjectKey(objectKey, lookup.getPath())) {

                     continue;

                 }

                 if (!matchesType(type, lookup.getType())) {

                     continue;

                 }

                 // TODO: figure out why path=courseInfo.creditOptions.type matches any structure that has a type on it so

                 // that lookup gets returned for all types

                 Map<String, Metadata> parsedMetadataMap = metadata.getProperties();

                 Metadata parsedMetadata = null;

                 String parsedMetadataKey = "";

                 String lookupFieldPath = lookup.getPath();

                 String[] lookupPathTokens = getPathTokens(lookupFieldPath);

                 for (int i = 1; i < lookupPathTokens.length; i++) {

                     if (parsedMetadataMap == null) {

                         break;

                     }

                     if (i == lookupPathTokens.length - 1) {

                         // get the metadata on the last path key token

                         parsedMetadata = parsedMetadataMap.get(lookupPathTokens[i]);

                         parsedMetadataKey = parsedMetadataKey + "." + lookupPathTokens[i];

                     }

                     if (parsedMetadataMap.get(lookupPathTokens[i]) != null) {

                         parsedMetadataMap = parsedMetadataMap.get(lookupPathTokens[i]).getProperties();

                     } else if (parsedMetadataMap.get("*") != null) {

                         // Lookup wildcard in case of unbounded elements in metadata.

                         parsedMetadataMap = parsedMetadataMap.get("*").getProperties();

                         i--;

                     }

                 }

                 if (parsedMetadata != null) {

                     // System.out.println ("addLookupstoMetadata:" + parsedMetadataKey + " was found as a match for " +

                     // lookup.getPath ());

                     UILookupData initialLookup = lookup.getInitialLookup();

                     if (initialLookup != null) {

                         mapLookupDatatoMeta(initialLookup);

                         parsedMetadata.setInitialLookup(mapLookupDatatoMeta(lookup.getInitialLookup()));

                     }

                     List<LookupMetadata> additionalLookupMetadata = null;

                     if (lookup.getAdditionalLookups() != null) {

                         additionalLookupMetadata = new ArrayList<LookupMetadata>();

                         for (UILookupData additionallookup : lookup.getAdditionalLookups()) {

                             additionalLookupMetadata.add(mapLookupDatatoMeta(additionallookup));

                         }

                         parsedMetadata.setAdditionalLookups(additionalLookupMetadata);

                     }

                 }

             }

         }

     }

     private LookupMetadata mapLookupDatatoMeta(UILookupData lookupData) {

         LookupMetadata lookupMetadata = new LookupMetadata();

         List<LookupParamMetadata> paramsMetadata;

         BeanUtils.copyProperties(lookupData, lookupMetadata, new String[]{"widget", "usage", "widgetOptions", "params"});

         if (lookupData.getWidget() != null) {

             lookupMetadata.setWidget(org.kuali.student.core.assembly.data.LookupMetadata.Widget.valueOf(lookupData.getWidget().toString()));

         }

         if (lookupData.getUsage() != null) {

             lookupMetadata.setUsage(org.kuali.student.core.assembly.data.LookupMetadata.Usage.valueOf(lookupData.getUsage().toString()));

         }

         if (lookupData.getWidgetOptions () != null) {

          lookupMetadata.setWidgetOptions (new HashMap ());

          for (UILookupData.WidgetOption wo: lookupData.getWidgetOptions ().keySet ()) {

           String value = lookupData.getWidgetOptions ().get (wo);

           LookupMetadata.WidgetOption key = LookupMetadata.WidgetOption.valueOf(wo.toString());

           lookupMetadata.getWidgetOptions ().put (key, value);

          }

         }

         if (lookupData.getParams() != null) {

             paramsMetadata = new ArrayList<LookupParamMetadata>();

             for (CommonLookupParam param : lookupData.getParams()) {

                 paramsMetadata.add(mapLookupParamMetadata(param));

             }

             lookupMetadata.setParams(paramsMetadata);

         }

         // WidgetOptions is not used as of now. So not setting it into metadata.

         return lookupMetadata;

     }

     private LookupParamMetadata mapLookupParamMetadata(CommonLookupParam param) {

         LookupParamMetadata paramMetadata = new LookupParamMetadata();

         BeanUtils.copyProperties(param, paramMetadata, new String[]{"childLookup", "dataType", "writeAccess", "usage", "widget"});

         if (param.getChildLookup() != null) {

             paramMetadata.setChildLookup(mapLookupDatatoMeta((UILookupData) param.getChildLookup()));

         }

         if (param.getDataType() != null) {

             paramMetadata.setDataType(org.kuali.student.core.assembly.data.Data.DataType.valueOf(param.getDataType().toString()));

         }

         if (param.getWriteAccess() != null) {

             paramMetadata.setWriteAccess(org.kuali.student.core.assembly.data.Metadata.WriteAccess.valueOf(param.getWriteAccess().toString()));

         }

         if (param.getUsage() != null) {

             paramMetadata.setUsage(org.kuali.student.core.assembly.data.LookupMetadata.Usage.valueOf(param.getUsage().toString()));

         }

         if (param.getWidget() != null) {

             paramMetadata.setWidget(org.kuali.student.core.assembly.data.LookupParamMetadata.Widget.valueOf(param.getWidget().toString()));

         }

         return paramMetadata;

     }

     private static String[] getPathTokens(String fieldPath) {

         return (fieldPath != null && fieldPath.contains(".") ? fieldPath.split("\\.") : new String[]{fieldPath});

     }

 }