package org.eclipse.emf.refactor.smells.eraser.ui;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.eclipse.emf.ecore.EAttribute;
import org.eclipse.emf.ecore.ENamedElement;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.EOperation;
import org.eclipse.emf.refactor.refactoring.core.Refactoring;
import org.eclipse.emf.refactor.smells.core.ModelSmell;
import org.eclipse.emf.refactor.smells.eraser.managers.EraseManager;
import org.eclipse.emf.refactor.smells.eraser.utils.SetSorter;
import org.eclipse.emf.refactor.smells.runtime.core.EObjectGroup;
import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.TableEditor;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Combo;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.TabFolder;
import org.eclipse.swt.widgets.TabItem;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.swt.widgets.TableItem;

/**
 * Dialog class for providing the user with suggestions for applicable refactorings based on a given
 * smell occurence.
 * 
 * @author Matthias Burhenne
 *
 */

public class SuggestionDialog extends Dialog {
	
	private static final String APPLICABLE_REFACTORINGS_TAB_LABEL = "Applicable Refactorings";
	private static final String SUGGESTED_REFACTORINGS_TAB_LABEL = "Suggested Refactorings";
	private static final String CONTEXT_OBJECTS = "contextObjects";
	private static final String SELECTED_CONTEXT_OBJECT = "selectedContextObject";
	private static final String POSSIBLE_SMELLS_COLUMNL_LABEL = "Possible Smells";
	private static final String DESCRIPTION_COLUMN_LABEL = "Description";
	private static final String CONTEXT_COLUMN_LABEL = "Context";
	private static final String REFACTORING_NAME_COLUMN_LABEL = "Refactoring";
	
	private static final String NO_MODEL_ELEMENT_SELECTED_ERROR_MESSAGE = "No model element was selected. In order to perform the\n" + 
																			"selected refactoring a context object is needed.\n" +
																			"Please select it via the combo box in column " + CONTEXT_COLUMN_LABEL + "!";
	private static final String NO_REFACTORING_SELECTED_ERROR_MESSAGE = "No refactoring was selected. Please select a refactoring\n" +
																			"by selecting one of the table rows!";
	private static final String NO_CONTEXT_ELEMENT_SELECTED_ERROR_TITLE = "No model element selected";
	private static final String NO_REFACTORING_SELECTED_ERROR_MESSAGE_TITLE = "No refactoring selected";
	
	private static final int CONTEXT_COLUMN_INDEX = 1;
	private static final String REFACTORING_TABLE_ITEM_DATA = "refactoring";
	private static final String CONTEXT_OBJECTS_COMBO = "contextObjectsCombo";
	private final Map<Refactoring, Set<ModelSmell>> relationMap;
	private final EObjectGroup eObjects;
	private final Map<Refactoring, Set<EObject>> dynamicallyCalculatedRefactorings;
	
	private Refactoring selectedRefactoring = null;
	private EObject selectedContextObject = null;
	private TableItem selectedItem = null;
	private Table staticTable;
	private Table dynamicTable;
	
	public SuggestionDialog(Shell parentShell, Map<Refactoring, Set<ModelSmell>> relationMap, EObjectGroup eObjects) {
		super(parentShell);
		this.relationMap = relationMap;
		this.eObjects = eObjects;
		this.dynamicallyCalculatedRefactorings = EraseManager.getApplicableRefactoringsDynamically(eObjects);
		
	}
	
	protected void configureShell(Shell shell) {
		super.configureShell(shell);
	    shell.setText("Refactoring Quick Fix Dialog");
	}
	
	@Override
	protected Control createContents(Composite parent) {
		
		parent.setLayout(new GridLayout(1, true));
		
		
		TabFolder tabs = new TabFolder(parent, SWT.NULL);
		GridData gridData = new GridData(GridData.FILL_BOTH);
		gridData.horizontalAlignment = GridData.FILL;
		tabs.setLayoutData(gridData);
		
		TabItem staticDefinitionsTab = new TabItem(tabs, SWT.NULL);
		staticDefinitionsTab.setText(SUGGESTED_REFACTORINGS_TAB_LABEL);
		Composite staticComposite = new Composite(tabs, SWT.NULL);
		staticComposite.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
		staticDefinitionsTab.setControl(staticComposite);
		GridLayout staticLayout = new GridLayout();
		staticComposite.setLayout(staticLayout);
		
		staticTable = new Table(staticComposite, SWT.SINGLE
				| SWT.FULL_SELECTION | SWT.BORDER | SWT.V_SCROLL);
		createRelationTableColumns(staticTable);
		
		try {
			fillStaticRelationsTable(staticTable);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
		
		staticTable.setHeaderVisible(true);
		staticTable.setLinesVisible(true);
		
		TabItem dynamicRelationsTab = new TabItem(tabs, SWT.NULL);
		dynamicRelationsTab.setText(APPLICABLE_REFACTORINGS_TAB_LABEL);
		Composite dynamicComposite = new Composite(tabs, SWT.NULL);
		dynamicComposite.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
		dynamicRelationsTab.setControl(dynamicComposite);
		GridLayout dynamicLayout = new GridLayout();
		dynamicComposite.setLayout(dynamicLayout);
		
		dynamicTable = new Table(dynamicComposite, SWT.SINGLE
				| SWT.FULL_SELECTION | SWT.BORDER | SWT.V_SCROLL);
		createRelationTableColumns(dynamicTable);
		
		fillDynamicRelationsTable(dynamicallyCalculatedRefactorings, dynamicTable);
		
		dynamicTable.setHeaderVisible(true);
		dynamicTable.setLinesVisible(true);
		
		return super.createContents(parent);
	}
	
	/*
	 * fills the table contained in the tab for applicable refactorings
	 */
	private void fillDynamicRelationsTable(
			Map<Refactoring, Set<EObject>> dynamicMap,
			Table dynamicTable) {
		for(Refactoring refactoring : SetSorter.sortRefactoringSet(dynamicMap.keySet())){
				String causedSmells = buildCausedSmellsTableEntry(refactoring);
				TableItem tableItem = new TableItem(dynamicTable, SWT.LEFT);
				tableItem.setText(0, refactoring.getName());
				tableItem.setText(1, refactoring.getNamespaceUri());
				tableItem.setText(2, refactoring.getId());
				tableItem.setText(3, causedSmells);

				Combo contextObjectsCombo = new Combo(dynamicTable, SWT.LEFT);
				for(EObject contextObject : dynamicMap.get(refactoring)){
					String label = getEObjectLabel(contextObject);
					contextObjectsCombo.add(label);
					contextObjectsCombo.setData(label, contextObject);
				}
				tableItem.setData(REFACTORING_TABLE_ITEM_DATA, refactoring);
				tableItem.setData(CONTEXT_OBJECTS_COMBO, contextObjectsCombo);
				
				ArrayList<EObject> contextObjects = new ArrayList<EObject>();
				contextObjects.addAll(dynamicMap.get(refactoring));
				tableItem.setData(CONTEXT_OBJECTS, contextObjects);
		}
	}

	/*
	 * Fills the table for refactorings suggested in the tab containing the suggested refactorings
	 */
	private void fillStaticRelationsTable(Table table) throws ClassNotFoundException {
		Refactoring[] refactorings = {};
		refactorings = relationMap.keySet().toArray(refactorings);
		Arrays.sort(refactorings);
		for(Refactoring refactoring : refactorings){
			String smells = buildCausedSmellsTableEntry(refactoring);
			ArrayList<EObject> contextObjects = new ArrayList<EObject>();
			for(EObject eObject : eObjects.getEObjects()){
				if(EraseManager.passesInitialCheck(eObject, refactoring)){
					contextObjects.add(eObject);
				}
			}		
			TableItem tableItem = new TableItem(table, SWT.LEFT);
			tableItem.setText(0, refactoring.getName());
			tableItem.setText(1, refactoring.getNamespaceUri());
			tableItem.setText(2, refactoring.getId());
			tableItem.setText(3, smells);
					
			
			Combo contextObjectsCombo = new Combo(table, SWT.LEFT);
			for(EObject contextObject : contextObjects){
				String label = getEObjectLabel(contextObject);
				contextObjectsCombo.add(label);
				contextObjectsCombo.setData(label, contextObject);
			}
			tableItem.setData(REFACTORING_TABLE_ITEM_DATA, refactoring);
			tableItem.setData(CONTEXT_OBJECTS_COMBO, contextObjectsCombo);
			tableItem.setData(CONTEXT_OBJECTS, contextObjects);
		}
		
	}

	/*
	 * Builds a String for the table column containing the names of possibly caused smells
	 */
	private String buildCausedSmellsTableEntry(Refactoring refactoring) {
		String smells = "";
		
		Set<ModelSmell> currentSet = EraseManager.getCausedModelSmells(refactoring);
		if(currentSet != null){
			for(ModelSmell smell : currentSet){
				smells += smell.getName() + ", ";
			}
			if(smells.endsWith(", ") && smells.length() > 2){
				smells = smells.substring(0, smells.length()-2);
			}
		}
		return smells;
	}

	/*
	 * Adds the columns to the tables inside the two tabs
	 */
	private void createRelationTableColumns(Table table) {
		//Column 1:
		TableColumn refactoringNameColumn = new TableColumn(table, SWT.LEFT);
		refactoringNameColumn.setText(REFACTORING_NAME_COLUMN_LABEL);
		refactoringNameColumn.setWidth(250);
		
		//Column 2:
		TableColumn refactoringContextColumn = new TableColumn(table, SWT.LEFT);
		refactoringContextColumn.setText(CONTEXT_COLUMN_LABEL);
		refactoringContextColumn.setWidth(150);
		
		//Column 3:
		TableColumn refactoringDescriptionColumn = new TableColumn(table, SWT.LEFT);
		refactoringDescriptionColumn.setText(DESCRIPTION_COLUMN_LABEL);
		refactoringDescriptionColumn.setWidth(300);
		
		//Column 4:
		TableColumn causedSmellsColumn = new TableColumn(table, SWT.LEFT);
		causedSmellsColumn.setText(POSSIBLE_SMELLS_COLUMNL_LABEL);
		causedSmellsColumn.setWidth(300);
		
		final TableEditor tableEditor = new TableEditor(table);
		final Table editorTable = table;
		tableEditor.horizontalAlignment = SWT.LEFT;
		tableEditor.grabHorizontal = true;
		tableEditor.minimumWidth = refactoringContextColumn.getWidth();
		
		table.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(SelectionEvent e) {
				TableItem item = (TableItem) e.item;
			    if (item == null)
			       	return;
			    String oldSelectedText = item.getText(CONTEXT_COLUMN_INDEX);
			    Combo oldEditor = (Combo)tableEditor.getEditor();
			    if(oldEditor != null && selectedItem != null){
			    	String oldLabel = oldEditor.getText();
				    selectedItem.setText(CONTEXT_COLUMN_INDEX, oldLabel);
			    	oldEditor.dispose();
			    }
			    selectedItem = item;
			    Combo newEditor = new Combo(editorTable, SWT.NONE);
			    @SuppressWarnings("unchecked")
				List<EObject> contextObjects = (List<EObject>)item.getData(CONTEXT_OBJECTS);
			    for(EObject contextObject : contextObjects){
			    	String label = getEObjectLabel(contextObject);
			    	newEditor.setData(label, contextObject);
			    	newEditor.add(label);
			    }
			    for(int i = 0; i < newEditor.getItemCount(); i++){
			    	if(newEditor.getItem(i).equals(oldSelectedText)){
			    		newEditor.select(i);
			    		selectedItem.setData(SELECTED_CONTEXT_OBJECT, newEditor.getData("" + i));
			    	}
			    }
			    newEditor.addModifyListener(new ModifyListener() {
					
					@Override
					public void modifyText(ModifyEvent e) {
						Combo me = (Combo)e.widget;
						int index = me.getSelectionIndex();
						String key = me.getItem(index);
						EObject contextObject = (EObject)me.getData(key);
						selectedItem.setData(SELECTED_CONTEXT_OBJECT, contextObject);		
					}
				});
			    newEditor.setFocus();
			    tableEditor.setEditor(newEditor, item, CONTEXT_COLUMN_INDEX);
			}
		});		
	}
	
	/**
	 * Getter for the selected refactoring. To be used after okPressed() has been called.
	 * Will return null beforehand.
	 * @return - the Refactoring selected by the user or null
	 */
	public Refactoring getSelectedRefactoring(){
		return selectedRefactoring;
	}
	
	/**
	 * Getter for the selected context object. To be used after okPressed() has been called.
	 * Will return null beforehand.
	 * @return - the EObject selected by the user or null
	 */
	public EObject getSelectedContextObject(){
		return selectedContextObject;
	}

	@Override
	protected void okPressed() {
		try{
			if(selectedItem != null){
				selectedContextObject = (EObject) selectedItem.getData(SELECTED_CONTEXT_OBJECT); //selectedEObject;
				selectedRefactoring = (Refactoring)selectedItem.getData(REFACTORING_TABLE_ITEM_DATA);
			}
		}catch(NullPointerException ex){
			selectedContextObject = null;
			selectedRefactoring = null;
		}
		
		if(selectedRefactoring == null){
			org.eclipse.jface.dialogs.
			MessageDialog.openError(
				getShell(),
				NO_REFACTORING_SELECTED_ERROR_MESSAGE_TITLE,
				NO_REFACTORING_SELECTED_ERROR_MESSAGE);
			return;
		}
		
		if(selectedContextObject == null){
			org.eclipse.jface.dialogs.
			MessageDialog.openError(
				getShell(),
				NO_CONTEXT_ELEMENT_SELECTED_ERROR_TITLE,
				NO_MODEL_ELEMENT_SELECTED_ERROR_MESSAGE);
			return;
		}
		super.okPressed();
	}
	
	/*
	 * Builds the label used in the ComboBoxes for selecting the context object.
	 * The content of the label depends on the type of object and the available fields.
	 */
	private String getEObjectLabel(EObject eObject){
		String name = null;
		String label = null;
		String id = null;
		for (EAttribute attribute : eObject.eClass().getEAllAttributes()) {
			if (attribute.getName().equalsIgnoreCase("name")) {
				name = (String) eObject.eGet(attribute);
			}
		}
		for(EOperation operation : eObject.eClass().getEAllOperations()){
			try{
				if(operation.getName().equals("getName") && name == null)
					name = (String)eObject.eInvoke(operation, null);
				if(operation.getName().equals("getLabel") && label == null)
					label = (String)eObject.eInvoke(operation, null);
				if(operation.getName().equals("getID") && id == null)
					id = (String)eObject.eInvoke(operation, null);
				if(operation.getName().equals("getId") && id == null)
					id = (String)eObject.eInvoke(operation, null);
				} catch (Exception e) {
				} 
			}
		
		if(name != null && !name.isEmpty())
			return name;
		if(label != null && !label.isEmpty())
			return label;
		if(id != null && !id.isEmpty())
			return id;
		
		if(eObject instanceof ENamedElement)
			if(((ENamedElement) eObject).getName() != null && !((ENamedElement) eObject).getName().equals(""))
				return ((ENamedElement)eObject).getName();
			else
				return eObject.toString();
		else
			return eObject.toString();
		
	}
	
	

}