/**

  * 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.common.ui.client.widgets.search;

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.LinkedHashMap;

 import java.util.List;

 import java.util.Map;

 import org.kuali.student.common.ui.client.application.Application;

 import org.kuali.student.common.ui.client.configurable.mvc.DefaultWidgetFactory;

 import org.kuali.student.common.ui.client.mvc.Callback;

 import org.kuali.student.common.ui.client.widgets.KSButton;

 import org.kuali.student.common.ui.client.widgets.KSDropDown;

 import org.kuali.student.common.ui.client.widgets.KSLabel;

 import org.kuali.student.common.ui.client.widgets.KSButtonAbstract.ButtonStyle;

 import org.kuali.student.common.ui.client.widgets.buttongroups.ButtonEnumerations;

 import org.kuali.student.common.ui.client.widgets.buttongroups.ButtonEnumerations.ButtonEnum;

 import org.kuali.student.common.ui.client.widgets.field.layout.button.ActionCancelGroup;

 import org.kuali.student.common.ui.client.widgets.field.layout.button.ButtonGroup;

 import org.kuali.student.common.ui.client.widgets.field.layout.element.FieldElement;

 import org.kuali.student.common.ui.client.widgets.layout.HorizontalBlockFlowPanel;

 import org.kuali.student.common.ui.client.widgets.layout.VerticalFlowPanel;

 import org.kuali.student.common.ui.client.widgets.list.KSSelectItemWidgetAbstract;

 import org.kuali.student.common.ui.client.widgets.list.ListItems;

 import org.kuali.student.common.ui.client.widgets.list.SelectionChangeEvent;

 import org.kuali.student.common.ui.client.widgets.list.SelectionChangeHandler;

 import org.kuali.student.common.ui.client.widgets.searchtable.ResultRow;

 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.LookupMetadata.Usage;

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

 import org.kuali.student.core.search.dto.SearchParam;

 import org.kuali.student.core.search.dto.SearchRequest;

 import com.google.gwt.core.client.GWT;

 import com.google.gwt.event.dom.client.ClickEvent;

 import com.google.gwt.event.dom.client.ClickHandler;

 import com.google.gwt.user.client.ui.Composite;

 import com.google.gwt.user.client.ui.HTMLPanel;

 import com.google.gwt.user.client.ui.HasText;

 import com.google.gwt.user.client.ui.HasValue;

 import com.google.gwt.user.client.ui.SimplePanel;

 import com.google.gwt.user.client.ui.VerticalPanel;

 import com.google.gwt.user.client.ui.Widget;

 public class SearchPanel extends Composite{

     //Layout configuration

     private VerticalFlowPanel layout = new VerticalFlowPanel();

     private SimplePanel searchSelectorPanel = new SimplePanel();

     private VerticalFlowPanel resultsTablePanel = new VerticalFlowPanel();

     private HorizontalBlockFlowPanel enteredCriteriaString = new HorizontalBlockFlowPanel();

     private CollapsablePanel modifySearchPanel;

     private String criteriaInstructions = getMessage("searchPanelEnterFields");

     private KSLabel enteredCriteriaHeading = new KSLabel(getMessage("searchPanelCriteria"));

     private SearchResultsTable table;

     private boolean isMultiSelect = true;

         public static enum SearchStyle{ADVANCED, CUSTOM}; 

     private ActionCancelGroup actionCancelButtons;

     private String actionLabel = getMessage("search");  //set default action label

     private boolean resultsSelected = false;

     //Search data

     private List<LookupMetadata> lookups = new ArrayList<LookupMetadata>();

     private boolean multiSelect = false;

     private boolean resultsShown = false;    

     private SearchParametersWidget activeSearchParametersWidget = null;

     // uses "name" of the lookup metadata to lookup the widget that layouts the search UI

     private Map<String, SearchParametersWidget> searchParameterWidgetMap = new HashMap<String, SearchParametersWidget>();

     private List<SearchField> searchFields = new ArrayList<SearchField>();

     private List<Callback<LookupMetadata>> lookupChangedCallbacks = new ArrayList<Callback<LookupMetadata>>();    

     private String selectedLookupName;

     private List<Callback<List<SelectedResults>>> selectedCompleteCallbacks = new ArrayList<Callback<List<SelectedResults>>>();  

     private List<Callback<Boolean>> actionCompletedCallbacks = new ArrayList<Callback<Boolean>>();    

     interface SearchParametersWidget {

         public SearchRequest getSearchRequest();

         public LookupMetadata getLookupMetadata();

         public List<HasSearchParam> getSearchParams();

     }

     public SearchPanel(LookupMetadata meta){

         lookups.add(meta);

    //     setupSearch();

         this.initWidget(layout);

     }

     public SearchPanel(List<LookupMetadata> metas){

         lookups = metas;       

    //     setupSearch();

         this.initWidget(layout);

     }

     @SuppressWarnings("unchecked")

         public ButtonGroup getButtons(){

             return actionCancelButtons;

     }

     public void setMutipleSelect(boolean isMultiSelect){

             this.isMultiSelect = isMultiSelect;

     }

     public void setupButtons() {

         if (actionCancelButtons != null) {

             actionCancelButtons.setButtonText(ButtonEnumerations.SearchCancelEnum.SEARCH, getActionLabel());

             actionCancelButtons.addCallback(new Callback<ButtonEnumerations.ButtonEnum>(){

                 @Override

                public void exec(ButtonEnum result) {

                     if (result == ButtonEnumerations.SearchCancelEnum.SEARCH) {

                         getActionCompleteCallback().exec(true);                                 

                     }

                }

            });            

         }            

     }

     public void setupSearch() {

         resultsTablePanel.clear();

         layout.clear();

         resultsShown = false;

         //create search panel

         Widget searchParamPanel;        

         if (lookups.size() == 1) {

             searchParamPanel = createSearchParamPanel(lookups.get(0));

             selectedLookupName = lookups.get(0).getName();

             activeSearchParametersWidget = searchParameterWidgetMap.get(selectedLookupName);

         } else {

             LinkedHashMap<String, Widget> searches = new LinkedHashMap<String, Widget>();

             LinkedHashMap<String, LookupMetadata> searchLookups = new LinkedHashMap<String, LookupMetadata>();

             for(LookupMetadata lookup: lookups){

                 searches.put(lookup.getName(), createSearchParamPanel(lookup));

                 searchLookups.put(lookup.getName(), lookup);

             }

             selectedLookupName = lookups.get(0).getName();

             // Sets the activeSearchParametersWidget to be the first search

             activeSearchParametersWidget = searchParameterWidgetMap.get(selectedLookupName);

             String actionLabel = (lookups.get(0) == null)? null : lookups.get(0)

                     .getWidgetOptionValue(LookupMetadata.WidgetOption.ADVANCED_LIGHTBOX_ACTION_LABEL);

             setActionLabel(actionLabel);

             searchParamPanel = new SwappablePanel(searches);

             ((SwappablePanel)searchParamPanel).setSearchLookups(searchLookups);

             ((SwappablePanel)searchParamPanel).addLookupChangedCallback(new Callback<LookupMetadata>() {

                 @Override

                 public void exec(LookupMetadata selectedLookup) {

                     activeSearchParametersWidget = searchParameterWidgetMap.get(selectedLookup.getName());

                     selectedLookupName = selectedLookup.getName();

                     if (lookupChangedCallbacks != null) {

                         for (Callback<LookupMetadata> callback : lookupChangedCallbacks) {

                             callback.exec(selectedLookup);

                         }

                     }

                 }

             });

         }

         searchSelectorPanel.setWidget(searchParamPanel);

         layout.add(searchSelectorPanel);

         //create layout for results screen

         enteredCriteriaHeading.addStyleName("ks-form-module-single-line-margin");

         enteredCriteriaHeading.addStyleName("KS-Advanced-Search-Search-Criteria-Label");

         resultsTablePanel.add(enteredCriteriaHeading);

         resultsTablePanel.add(enteredCriteriaString);

         resultsTablePanel.setVisible(false);        

         table = new SearchResultsTable();

         table.setMutipleSelect(isMultiSelect);

         table.addStyleName("KS-Advanced-Search-Results-Table");

         resultsTablePanel.add(table);

         layout.add(resultsTablePanel); 

         resultsSelected = false;

         actionCancelButtons.setButtonText(ButtonEnumerations.SearchCancelEnum.SEARCH, getActionLabel());

     }

     private Widget createSearchParamPanel(LookupMetadata meta){

         ParamListItems listItems = new ParamListItems(meta);

         final AdvancedSearch advancedSearch = new AdvancedSearch(meta);

         LinkPanel panel = new LinkPanel(SearchStyle.ADVANCED, advancedSearch);

         searchParameterWidgetMap.put(meta.getName(), advancedSearch);

         //check whether we need custom tab i.e. whether we have at least one parameter that should appear on custom tab

         for(LookupParamMetadata metaParam: meta.getParams()){

             if ((metaParam.getUsage() == Usage.CUSTOM) || (metaParam.getUsage() == Usage.ADVANCED_CUSTOM)) {

                 final CustomizedSearch customizedSearch = new CustomizedSearch(meta, listItems);

                 KSButton button = panel.addLinkToPanel(SearchStyle.ADVANCED, getMessage("searchPanelCustomizeSearch"), SearchStyle.CUSTOM);

                 button.addClickHandler(new ClickHandler(){

                     @Override

                     public void onClick(ClickEvent event) {

                         resultsTablePanel.setVisible(false);

                         activeSearchParametersWidget = customizedSearch;

                     }});

                 button.addStyleName("KS-Advanced-Search-Link");

                 button.getParent().addStyleName("clearfix");

                 panel.addPanel(SearchStyle.CUSTOM, customizedSearch);

                 button = panel.addLinkToPanel(SearchStyle.CUSTOM, getMessage("searchPanelReturnToAdvancedSearch"), SearchStyle.ADVANCED);

                 button.addClickHandler(new ClickHandler(){

                     @Override

                     public void onClick(ClickEvent event) {

                         resultsTablePanel.setVisible(false);

                         activeSearchParametersWidget = advancedSearch;

                     }});

                 button.addStyleName("KS-Advanced-Search-Link");

                 button.getParent().addStyleName("clearfix");

                 break;

             }

         }

         return panel;

     }

     private class CustomizedSearch extends Composite implements SearchParametersWidget {

         private List<CustomLine> lines = new ArrayList<CustomLine>();

         private List<HasSearchParam> searchParams = new ArrayList<HasSearchParam>();

         private VerticalPanel layout = new VerticalPanel();

         private VerticalPanel linePanel = new VerticalPanel();

         private LookupMetadata meta;

         public CustomizedSearch(final LookupMetadata meta, final ParamListItems listItems){

             KSLabel instrLabel = new KSLabel(criteriaInstructions);

             layout.add(instrLabel);

             layout.add(linePanel);

             CustomLine line = new CustomLine(meta, listItems);

             line.addStyleName("ks-form-module-single-line-margin");

             linePanel.add(line);

             lines.add(line);

             searchParams.add(line);

             this.meta = meta;

             KSButton addCriteria = new KSButton(getMessage("searchPanelAddCriteria"), ButtonStyle.SECONDARY);

             addCriteria.addClickHandler(new ClickHandler(){

                 @Override

                 public void onClick(ClickEvent event) {

                     CustomLine line = new CustomLine(meta, listItems);

                     line.addStyleName("ks-form-module-single-line-margin");

                     linePanel.add(line);

                     lines.add(line);

                     searchParams.add(line);

                 }

             });

             addCriteria.addStyleName("ks-form-module-single-line-margin");

             layout.add(addCriteria);    

             this.initWidget(layout);

         }

         public LookupMetadata getLookupMetadata() {

             return meta;

         }

         @Override

         public SearchRequest getSearchRequest() {

             //Create search request and then pass it to the table

             //TODO pass search to the table

             SearchRequest sr = new SearchRequest();

             List<SearchParam> params = new ArrayList<SearchParam>();

             for(CustomLine field: lines){

                 SearchParam param = field.getSearchParam();

                 //TODO is this check needed here? probably. assuming string here

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

                     params.add(param);

                 }

             }

             //add search criteria widgets to the custom tab

             for(LookupParamMetadata metaParam: meta.getParams()){

                 //select only parameters shown on custom search tab

                 if ((metaParam.getUsage() != Usage.CUSTOM) && (metaParam.getUsage() != Usage.ADVANCED_CUSTOM)) {

                     continue;

                 }

                 if(metaParam.getWriteAccess() == WriteAccess.NEVER){

                     SearchParam param = new SearchParam();

                     param.setKey(metaParam.getKey());

                     if(metaParam.getDefaultValueList()==null){

                         param.setValue(metaParam.getDefaultValueString());

                     }else{

                         param.setValue(metaParam.getDefaultValueList());

                     }

                     params.add(param);

                 }

                 else if(metaParam.getWriteAccess() == WriteAccess.WHEN_NULL){

                     if((metaParam.getDefaultValueString() != null && !metaParam.getDefaultValueString().isEmpty())||

                        (metaParam.getDefaultValueList() != null && !metaParam.getDefaultValueList().isEmpty())){

                         SearchParam param = new SearchParam();

                         param.setKey(metaParam.getKey());

                         if(metaParam.getDefaultValueList()==null){

                             param.setValue(metaParam.getDefaultValueString());

                         }else{

                             param.setValue(metaParam.getDefaultValueList());

                         }

                         params.add(param);

                     }

                 }

             }

             sr.setParams(params);

             sr.setSearchKey(meta.getSearchTypeId());

             return sr;

         }

         @Override

         public List<HasSearchParam> getSearchParams() {

             return searchParams;

         }

     }

     private interface HasSearchParam{

         public SearchParam getSearchParam();

         public String getFieldName();

     }

     private static class CustomLine extends Composite implements HasSearchParam{

         private KSDropDown paramSelector = new KSDropDown();

         private SimplePanel widgetPanel = new SimplePanel();

         private Widget widget = null;

         private String key;

         private HorizontalBlockFlowPanel layout = new HorizontalBlockFlowPanel();

         private ParamListItems listItems;

         public CustomLine(LookupMetadata meta, final ParamListItems listItems){

             List<LookupParamMetadata> customParams = new ArrayList<LookupParamMetadata>();

             for (LookupParamMetadata lookupParamMetadata : listItems.getParams()) {

                 if (lookupParamMetadata.getWriteAccess() != WriteAccess.NEVER){

                     if (lookupParamMetadata.getUsage() == Usage.CUSTOM || lookupParamMetadata.getUsage() == Usage.ADVANCED_CUSTOM ) {

                         customParams.add(lookupParamMetadata);

                     }                   

                 } 

             }

             ParamListItems customParamList = new ParamListItems(customParams);

             this.listItems = customParamList;

             paramSelector.setBlankFirstItem(false);

             paramSelector.setListItems(customParamList);

             String id = meta.getParams().get(0).getKey();

             paramSelector.selectItem(id);

             widget = listItems.getWidget(id);

             key = id;

             widgetPanel.setWidget(widget);

             paramSelector.addSelectionChangeHandler(new SelectionChangeHandler(){

                 @Override

                 public void onSelectionChange(SelectionChangeEvent event) {

                     String id = ((KSSelectItemWidgetAbstract)event.getWidget()).getSelectedItem();

                     widget = listItems.getWidget(id);

                     widgetPanel.setWidget(widget);

                     key = id;

                 }

             });

             layout.add(paramSelector);

             layout.add(widgetPanel);

             this.initWidget(layout);

         }

         public SearchParam getSearchParam(){

             return SearchPanel.getSearchParam(widget, key);

         }

         public String getKey(){

             return key;

         }

         public String getFieldName(){

             String id = paramSelector.getSelectedItem();

             return listItems.getItemText(id);

         }

     }

     private class AdvancedSearch extends Composite implements SearchParametersWidget {

         private LookupMetadata meta;

         private List<HasSearchParam> searchParams = new ArrayList<HasSearchParam>();

         public AdvancedSearch(final LookupMetadata meta){

             VerticalPanel panel = new VerticalPanel();

             KSLabel instrLabel = new KSLabel();

             panel.add(instrLabel);

             this.meta = meta;            

             //add widget for each search criteria to the advanced tab

             boolean allFieldsRequired = true;

             for(LookupParamMetadata param: meta.getParams()){

                 //select only parameters shown on advanced search tab

                 if ((param.getUsage() != Usage.ADVANCED) && (param.getUsage() != Usage.ADVANCED_CUSTOM)) {

                     continue;

                 }

                 if ((param.getWriteAccess() == WriteAccess.ALWAYS) || (param.getWriteAccess() == WriteAccess.REQUIRED)){

                     SearchField paramField = new SearchField(param);

                     searchFields.add(paramField);

                     panel.add(paramField);

                     searchParams.add(paramField);

                 }

                 else if (param.getWriteAccess() == WriteAccess.WHEN_NULL){

                     if(param.getDefaultValueString() == null && param.getDefaultValueList() == null){

                         SearchField paramField = new SearchField(param);

                         searchFields.add(paramField);

                         panel.add(paramField);

                         searchParams.add(paramField);

                     }

                 }

                 if (param.getWriteAccess() != Metadata.WriteAccess.REQUIRED) {

                     allFieldsRequired = false;

                 }

             }

             //do not show criteria instructions if we have only one criteria field or in case all fields are required

             if ((searchFields.size() > 1) || (allFieldsRequired == false)) {

                 instrLabel.setText(criteriaInstructions);

             }    

             this.initWidget(panel);

         }

         public LookupMetadata getLookupMetadata() {

             return meta;

         }        

         @Override

         public SearchRequest getSearchRequest() {

             SearchRequest sr = new SearchRequest();

             List<SearchParam> params = new ArrayList<SearchParam>();

             List<HasSearchParam> searchParams = getSearchParams();

             //initialize search parameters if user entered values into search criteria fields in UI

             for(HasSearchParam field: searchParams){

                 SearchParam param = field.getSearchParam();

                 //TODO is this null check needed here? probably. assuming string here

                 //TODO make check more robust here/inserting params more robust

                 //do not pass to the search parameters that are empty

                 //FIXME hack - comparison to 'optional' - replace with check against 'optional' field and update related lookup metadata

                 if ((param.getValue() != null) && ((param.getValue().toString().trim().isEmpty() == false) || (param.getKey().toLowerCase().indexOf("optional") == -1))) {

                     params.add(param);

                 }

             }

             //initialize search parameters that are hidden from the UI because they are set to default context specific values

             for(LookupParamMetadata metaParam: meta.getParams()){

                 if(metaParam.getWriteAccess() == WriteAccess.NEVER){

                     if ((metaParam.getDefaultValueString() == null || metaParam.getDefaultValueString().isEmpty())&&

                         (metaParam.getDefaultValueList() == null || metaParam.getDefaultValueList().isEmpty())) {

                         //FIXME throw an exception?

                         GWT.log("Key = " + metaParam.getKey() + " has write access NEVER but has no default value!", null);

                         continue;

                     }

                     SearchParam param = new SearchParam();

                     param.setKey(metaParam.getKey());

                     if(metaParam.getDefaultValueList()==null){

                         param.setValue(metaParam.getDefaultValueString());

                     }else{

                         param.setValue(metaParam.getDefaultValueList());

                     }

                     params.add(param);

                 }

                 else if(metaParam.getWriteAccess() == WriteAccess.WHEN_NULL){

                     if((metaParam.getDefaultValueString() != null && !metaParam.getDefaultValueString().isEmpty())||

                        (metaParam.getDefaultValueList() != null && !metaParam.getDefaultValueList().isEmpty())){

                         SearchParam param = new SearchParam();

                         param.setKey(metaParam.getKey());

                         if(metaParam.getDefaultValueList()==null){

                             param.setValue(metaParam.getDefaultValueString());

                         }else{

                             param.setValue(metaParam.getDefaultValueList());

                         }

                         params.add(param);

                     }

                 }

             }

             sr.setParams(params);

             if (meta.getResultSortKey() != null) {

                 sr.setSortColumn(meta.getResultSortKey());

             }

             sr.setSearchKey(meta.getSearchTypeId());

             return sr;

         }

         @Override

         public List<HasSearchParam> getSearchParams() {

             return searchParams;

         }

     }

     private static class SearchField extends Composite implements HasSearchParam{

         private Widget widget = null;

         private LookupParamMetadata meta = null;

         private VerticalFlowPanel panel = new VerticalFlowPanel();

         private String fieldName;

         public SearchParam getSearchParam(){

             return SearchPanel.getSearchParam(widget, meta.getKey());

         }

         public SearchField(LookupParamMetadata param){

             meta = param;

             //TODO use message call here

             fieldName = param.getName();

             widget = DefaultWidgetFactory.getInstance().getWidget(param);

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

                 //TODO Add handling of default value lists here

                 if(widget instanceof HasText){

                     ((HasText) widget).setText(param.getDefaultValueString().toString());

                 }

                 else if(widget instanceof HasValue){

                     ((HasValue) widget).setValue(param.getDefaultValueString());

                 }

             }

             //FIXME: remove because required field '*' indication will be part of FieldElement class

             if (param.getWriteAccess() == Metadata.WriteAccess.REQUIRED) {

                 fieldName += " *";

             }

             FieldElement fieldElement = new FieldElement(fieldName, widget);

             fieldElement.getTitleWidget().addStyleName("KS-Picker-Criteria-Text");

             panel.add(fieldElement);

             panel.addStyleName("clear");

             this.initWidget(panel);

         }

         public Widget getFieldPanel(){

             return panel;

         }

         public String getFieldName() {

             return fieldName;

         }

     }

     private static SearchParam getSearchParam(final Widget widget, String key){

         SearchParam param = new SearchParam();

         param.setKey(key);

         if(widget instanceof HasText){

             param.setValue(((HasText) widget).getText());

         }

         else if(widget instanceof HasValue){

             Object value = ((HasValue) widget).getValue();

             if(value != null){

             //TODO need to handle date and other types here, how they are converted for search, etc

                 if(value instanceof String){

                     param.setValue((String)value);

                 }

                 else{

                     param.setValue(value.toString());

                     GWT.log("Fields in search probably(?) shouldnt have values other than string", null);

                 }

             }

         }

         else if (widget instanceof KSPicker){

             param.setValue(((KSPicker)widget).getDisplayValue());

         }

         else {

             param.setValue("");

         }

         return param;

     }

     private void showCriteriaChosen(List<HasSearchParam> fields){

         enteredCriteriaString.clear();

         boolean first = true;;

         for(HasSearchParam field: fields){

             String name = field.getFieldName();

             //TODO Should be string only, needs type safety

             String value = field.getSearchParam().getValue().toString();

             if(!value.isEmpty()){

                 HTMLPanel label = new HTMLPanel(name + ": <b>" + value + "</b> ");

                 if (!first) {

                     label.addStyleName("KS-Advanced-Search-Search-Criteria-Text");

                 }

                 enteredCriteriaString.add(label);

                 first = false;

             }

         }

     }

     public List<String> getSelectedIds(){

         List<String> ids = new ArrayList<String>();

         if(table != null){

             ids = table.getSelectedIds();

         }

         return ids;

     }

     public List<SelectedResults> getSelectedValues() {

         List<SelectedResults> selectedValues = new ArrayList<SelectedResults>();

         if (table != null) {

             List<ResultRow> selectedRows = table.getSelectedRows();

             for (ResultRow row : selectedRows) {

                 String displayKey = row.getValue(activeSearchParametersWidget.getLookupMetadata().getResultDisplayKey());

                 String returnKey = row.getValue(activeSearchParametersWidget.getLookupMetadata().getResultReturnKey());

                 selectedValues.add(new SelectedResults(displayKey, returnKey, row));

                 if (multiSelect == false) {

                     break;

                 }

             }

         }

         return selectedValues;

     }

     public boolean isMultiSelect() {

         return multiSelect;

     }

     public void setMultiSelect(boolean multiSelect) {

         this.multiSelect = multiSelect;

     }

     private static class ParamListItems implements ListItems{

         private List<LookupParamMetadata> params = new ArrayList<LookupParamMetadata>();

         public ParamListItems(LookupMetadata meta){

             params = meta.getParams();

         }

         public ParamListItems(List<LookupParamMetadata> params){

             this.params = params;

         }

         @Override

         public List<String> getAttrKeys() {

             return new ArrayList<String>();

         }

         @Override

         public String getItemAttribute(String id, String attrkey) {

             return "";

         }

         @Override

         public int getItemCount() {

             return params.size();

         }

         @Override

         public List<String> getItemIds() {

             List<String> ids = new ArrayList<String>();

             for(LookupParamMetadata param: params){

                 ids.add(param.getKey());

             }

             return ids;

         }

         @Override

         public String getItemText(String id) {

             String itemText = id;

             for(LookupParamMetadata param: params){

                 if(param.getKey().equals(id)){

                     //TODO this should be a message key

                     itemText = param.getName();

                     break;

                 }

             }

             return itemText;

         }

         public Widget getWidget(String id){

             Widget w = null;

             for(LookupParamMetadata param: params){

                 if(param.getKey().equals(id)){

                     w = DefaultWidgetFactory.getInstance().getWidget(param);

                     break;

                 }

             }

             return w;

         }

         public List<LookupParamMetadata> getParams() {

             return params;

         }

     }

     private String getMessage(final String msgKey) {

         return Application.getApplicationContext().getMessage(msgKey);

     }

     public void addLookupChangedCallback(Callback<LookupMetadata> callback) {

         lookupChangedCallbacks.add(callback);

     }

     public Callback<Boolean> getActionCompleteCallback() {

         return new Callback<Boolean>() {

             @Override

             public void exec(Boolean result) {                               

                 if (resultsSelected == true) {

                     List<SelectedResults> selectedItems = getSelectedValues();

                     for(Callback<List<SelectedResults>> callback: selectedCompleteCallbacks){

                         callback.exec(selectedItems);

                     }  

                     return;

                 }

                 actionCancelButtons.setButtonText(ButtonEnumerations.SearchCancelEnum.SEARCH, getMessage("select"));

                 resultsSelected = true;

                 SearchRequest sr = getSearchRequest();

                 table.performSearch(sr, activeSearchParametersWidget.getLookupMetadata().getResults(), activeSearchParametersWidget.getLookupMetadata().getResultReturnKey());

                 resultsTablePanel.setVisible(true);

                 List<HasSearchParam> userCriteria = new ArrayList<HasSearchParam>();

                 List<HasSearchParam> searchParams = activeSearchParametersWidget.getSearchParams();

                 //initialize search parameters if user entered values into search criteria fields in UI

                 for(HasSearchParam field: searchParams){

                     SearchParam param = field.getSearchParam();

                     //TODO is this null check needed here? probably. assuming string here

                     //TODO make check more robust here/inserting params more robust

                     //do not pass to the search parameters that are empty

                     //FIXME hack - comparison to 'optional' - replace with check against 'optional' field and update related lookup metadata

                     if ((param.getValue() != null) && ((param.getValue().toString().trim().isEmpty() == false) || (param.getKey().toLowerCase().indexOf("optional") == -1))) {

                         userCriteria.add(field);

                     }

                 }

                 showCriteriaChosen(userCriteria);

                 if(!resultsShown){

                     searchSelectorPanel.removeFromParent();

                     modifySearchPanel = new CollapsablePanel(getMessage("searchPanelModifySearch"), searchSelectorPanel, false);

                     modifySearchPanel.getLabel().addClickHandler(new ClickHandler(){

                         @Override

                         public void onClick(ClickEvent event) {

                             resultsTablePanel.setVisible(false);

                             actionCancelButtons.setButtonText(ButtonEnumerations.SearchCancelEnum.SEARCH, getActionLabel());

                             resultsSelected = false;

                         }});

                     SearchPanel.this.layout.insert(modifySearchPanel, 0);

                 }

                 else{

                     modifySearchPanel.close();

                 }

                 resultsShown = true; 

                 for(Callback<Boolean> callback: actionCompletedCallbacks){

                     callback.exec( Boolean.valueOf(true));

                 }                

             }

         };

     }

     public SearchRequest getSearchRequest() {

         if (activeSearchParametersWidget != null) {

             return activeSearchParametersWidget.getSearchRequest();

         }

         return null;

     }    

     public void setActionCancelButtonGroup(ActionCancelGroup actionCancelButtons) {

         this.actionCancelButtons = actionCancelButtons;

     }

     public String getSelectedLookupName() {

         return selectedLookupName;

     }

     public void setSelectedLookupName(String selectedLookupName) {

         this.selectedLookupName = selectedLookupName;

     }        

     public void addSelectionCompleteCallback(Callback<List<SelectedResults>> callback){

         selectedCompleteCallbacks.add(callback);

     }   

     public void addActionCompleteCallback(Callback<Boolean> callback){

         actionCompletedCallbacks.add(callback);

     }

     public String getActionLabel() {

         return actionLabel;

     }

     public void setActionLabel(String actionLabel) {

         if ((actionLabel != null) && (actionLabel.trim().length() > 0)) {

             this.actionLabel = actionLabel;

         }

     }

 }