/*******************************************************************************
 * Copyright (c) 2012 Association for Decentralized Information Management in
 * Industry THTH ry.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.charts.ui;

import java.io.File;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.eclipse.core.runtime.preferences.InstanceScope;
import org.eclipse.jface.layout.GridDataFactory;
import org.eclipse.jface.layout.GridLayoutFactory;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.wizard.WizardPage;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.CCombo;
import org.eclipse.swt.custom.ScrolledComposite;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.FileDialog;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.swt.widgets.Text;
import org.eclipse.ui.preferences.ScopedPreferenceStore;
import org.simantics.NameLabelUtil;
import org.simantics.Simantics;
import org.simantics.browsing.ui.common.ColumnKeys;
import org.simantics.databoard.Bindings;
import org.simantics.databoard.parser.StringEscapeUtils;
import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.common.NamedResource;
import org.simantics.db.common.request.IsParent;
import org.simantics.db.common.request.UniqueRead;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.layer0.SelectionHints;
import org.simantics.history.csv.ColumnSeparator;
import org.simantics.history.csv.DecimalSeparator;
import org.simantics.history.csv.ExportInterpolation;
import org.simantics.layer0.Layer0;
import org.simantics.modeling.ModelingResources;
import org.simantics.modeling.ModelingUtils;
import org.simantics.modeling.preferences.CSVPreferences;
import org.simantics.modeling.ui.modelBrowser2.label.SubscriptionItemLabelRule;
import org.simantics.utils.datastructures.Arrays;
import org.simantics.utils.datastructures.Pair;
import org.simantics.utils.strings.AlphanumComparator;
import org.simantics.utils.ui.ISelectionUtils;


/**
 * @author Antti Villberg
 */
public class CSVExportPage extends WizardPage {

    CSVExportPlan       exportModel;
    CCombo              model;
    Table               item;
    Button              selectAllItems;
    SelectionAdapter    selectAllItemsListener;
    CCombo              exportLocation;

    CCombo decimalSeparator;
    CCombo columnSeparator;
    CCombo sampling;
    Text timeStep;
    Text startTime;
    Text timeStamps;
    CCombo samplingMode;
    Text singlePrecision;
    Text doublePrecision;

    Group resampling;

    Collection<Resource> initialSelection;

    List<Pair<NamedResource,List<NamedResource>>> models = new ArrayList<>();

    private Button      overwrite;

    ModifyListener m = (e) -> validatePage();

    SelectionListener s = new SelectionAdapter() {
        @Override
        public void widgetSelected(SelectionEvent e) {
            validatePage();
        }
    };

    protected CSVExportPage(CSVExportPlan model) {
        super("Export CSV Data", "Define Export Properties", null);
        this.exportModel = model;
    }

    @Override
    public void createControl(Composite parent) {
        ScrolledComposite scroller = new ScrolledComposite(parent, SWT.V_SCROLL);
        scroller.setExpandHorizontal(true);
        scroller.setExpandVertical(true);

        Composite container = new Composite(scroller, SWT.NONE);
        scroller.setContent(container);
        GridLayoutFactory.swtDefaults().spacing(20, 10).numColumns(3).applyTo(container);
        new Label(container, SWT.NONE).setText("Select a model:");
        model = new CCombo(container, SWT.BORDER);
        {
            model.setEditable(false);
            model.setText("");
            model.setToolTipText("Selects the Model To Export From");
            GridDataFactory.fillDefaults().grab(true, false).span(2, 1).applyTo(model);
        }

        new Label(container, SWT.NONE).setText("Exported items:");
        item = new Table(container, SWT.BORDER | SWT.MULTI | SWT.FULL_SELECTION | SWT.CHECK);
        {
            item.setToolTipText("Selects the Subscription Items");
            GridDataFactory.fillDefaults().grab(true, true).span(2, 1).hint(SWT.DEFAULT, 105).applyTo(item);
        }
        item.addSelectionListener(new SelectionAdapter() {
            @Override
            public void widgetSelected(SelectionEvent e) {
                if (e.detail == SWT.CHECK) {
                    TableItem[] selected = item.getSelection();
                    TableItem it = (TableItem) e.item;
                    boolean checkedWasSelected = Arrays.contains(selected, it);
                    if (checkedWasSelected) {
                        boolean check = it.getChecked();
                        for (TableItem i : selected)
                            i.setChecked(check);
                    }
                    int checked = countCheckedItems(item);
                    int totalItems = item.getItemCount();
                    updateSelectAll(checked > 0, checked < totalItems, false);
                    validatePage();
                }
            }
        });
        new Label(container, 0);
        selectAllItems = new Button(container, SWT.CHECK);
        {
            selectAllItems.setText("&Select All");
            selectAllItems.setToolTipText("Select/Deselect All Listed Subscription Items");
            GridDataFactory.fillDefaults().grab(true, false).span(2, 1).applyTo(selectAllItems);
        }
        selectAllItemsListener = new SelectionAdapter() {
            @Override
            public void widgetSelected(SelectionEvent e) {
                boolean select = selectAllItems.getSelection();
                updateSelectAll(select, false, false);
                item.setRedraw(false);
                for (TableItem it : item.getItems())
                    it.setChecked(select);
                item.setRedraw(true);

                validatePage();
            }
        };
        selectAllItems.addSelectionListener(selectAllItemsListener);

        new Label(container, SWT.NONE).setText("&Output file:");
        exportLocation = new CCombo(container, SWT.BORDER);
        {
            exportLocation.setText("");
            GridDataFactory.fillDefaults().grab(true, false).span(1, 1).applyTo(exportLocation);
            exportLocation.addModifyListener(m);
        }
        Button browseFileButton = new Button(container, SWT.PUSH);
        {
            browseFileButton.setText("Browse...");
            browseFileButton.setLayoutData(new GridData(SWT.RIGHT, SWT.CENTER, false, false));
            browseFileButton.addSelectionListener(new SelectionAdapter() {
                @Override
                public void widgetSelected(SelectionEvent e) {
                    FileDialog dialog = new FileDialog(getShell(), SWT.SAVE);
                    dialog.setText("Choose Output File");
                    dialog.setFilterPath(new File(exportLocation.getText()).getParent());
                    dialog.setFilterExtensions(new String[] { "*.csv" });
                    dialog.setFilterNames(new String[] { "Comma separated values (*.csv)" });
                    dialog.setOverwrite(false);
                    String file = dialog.open();
                    if (file == null)
                        return;
                    exportLocation.setText(file);
                    validatePage();
                }
            });
        }

        
        Label horizRule = new Label(container, SWT.BORDER);
        GridDataFactory.fillDefaults().hint(SWT.DEFAULT, 0).grab(true, false).span(3, 1).applyTo(horizRule);

        new Label(container, SWT.NONE).setText("&Decimal separator:");
        decimalSeparator = new CCombo(container, SWT.READ_ONLY | SWT.BORDER);
        for(DecimalSeparator s : DecimalSeparator.values())
            decimalSeparator.add(s.label);
        decimalSeparator.select(0);
        decimalSeparator.addSelectionListener(s);
        GridDataFactory.fillDefaults().grab(true, false).span(2, 1).applyTo(decimalSeparator);

        new Label(container, SWT.NONE).setText("&Column separator:");
        columnSeparator = new CCombo(container, SWT.READ_ONLY | SWT.BORDER);
        for(ColumnSeparator s : ColumnSeparator.values())
            columnSeparator.add(s.label);
        columnSeparator.select(0);
        columnSeparator.addSelectionListener(s);
        GridDataFactory.fillDefaults().grab(true, false).span(2, 1).applyTo(columnSeparator);

        new Label(container, SWT.NONE).setText("Sampling:");
        sampling = new CCombo(container, SWT.READ_ONLY | SWT.BORDER);
        sampling.add("Recorded samples");
        sampling.add("Resampled");
        sampling.select(0);
        sampling.addSelectionListener(s);
        GridDataFactory.fillDefaults().grab(true, false).span(2, 1).applyTo(sampling);

        resampling = new Group(container, SWT.NONE);
		resampling.setText("Resampling settings (not used with recorded samples)");
        GridDataFactory.fillDefaults().grab(true, false).span(3, 1).applyTo(resampling);
        GridLayoutFactory.swtDefaults().numColumns(3).applyTo(resampling);

        new Label(resampling, SWT.NONE).setText("&Start time:");
        startTime = new Text(resampling, SWT.BORDER);
        startTime.addModifyListener(m);
        GridDataFactory.fillDefaults().grab(true, false).applyTo(startTime);
        new Label(resampling, SWT.NONE).setText(" seconds");

        new Label(resampling, SWT.NONE).setText("&Time step:");
        timeStep = new Text(resampling, SWT.BORDER);
        timeStep.addModifyListener(m);
        GridDataFactory.fillDefaults().grab(true, false).applyTo(timeStep);
        new Label(resampling, SWT.NONE).setText(" seconds");
        
        new Label(resampling, SWT.NONE).setText("Sampling mode:");
        samplingMode = new CCombo(resampling, SWT.READ_ONLY | SWT.BORDER);
        samplingMode.add("Linear interpolation");
        samplingMode.add("Previous sample");
        samplingMode.select(0);
        samplingMode.addSelectionListener(s);
        GridDataFactory.fillDefaults().grab(true, false).span(2,1).applyTo(samplingMode);

        Group digits = new Group(container, SWT.NONE);
        digits.setText("Significant digits");
        GridDataFactory.fillDefaults().grab(true, false).span(3, 1).applyTo(digits);
        GridLayoutFactory.swtDefaults().numColumns(2).applyTo(digits);

        new Label(digits, SWT.NONE).setText("&Time stamps:");
        timeStamps = new Text(digits, SWT.BORDER);
        timeStamps.addModifyListener(m);
        GridDataFactory.fillDefaults().grab(true, false).applyTo(timeStamps);
        
        new Label(digits, SWT.NONE).setText("&Single precision floating point:");
        singlePrecision = new Text(digits, SWT.BORDER);
        singlePrecision.addModifyListener(m);
        GridDataFactory.fillDefaults().grab(true, false).applyTo(singlePrecision);

        new Label(digits, SWT.NONE).setText("&Double precision floating point:");
        doublePrecision = new Text(digits, SWT.BORDER);
        doublePrecision.addModifyListener(m);
        GridDataFactory.fillDefaults().grab(true, false).applyTo(doublePrecision);

        overwrite = new Button(container, SWT.CHECK);
        overwrite.setText("&Overwrite existing files without warning");
        overwrite.setSelection(exportModel.overwrite);
        GridDataFactory.fillDefaults().grab(true, false).span(3, 1).applyTo(overwrite);
        overwrite.addSelectionListener(new SelectionAdapter() {
            @Override
            public void widgetSelected(SelectionEvent e) {
                validatePage();
            }
        });

        try {
            initializeData();
        } catch (DatabaseException e) {
            e.printStackTrace();
        }

        model.addSelectionListener(s);

        scroller.setMinSize(container.computeSize(SWT.DEFAULT, SWT.DEFAULT));

        setControl(scroller);
        validatePage();
        
    }

    void updateSelectAll(boolean checked, boolean gray, boolean notify) {
        if (checked) {
            selectAllItems.setText("Select None");
        } else {
            selectAllItems.setText("Select All");
        }
        if (!notify)
            selectAllItems.removeSelectionListener(selectAllItemsListener);
        selectAllItems.setGrayed(checked && gray);
        selectAllItems.setSelection(checked);
        if (!notify)
            selectAllItems.addSelectionListener(selectAllItemsListener);
    }

    protected int countCheckedItems(Table table) {
        int ret = 0;
        for (TableItem item : table.getItems())
            ret += item.getChecked() ? 1 : 0;
        return ret;
    }

    private void initializeData() throws DatabaseException {

        // Write preferences to formatter
        IPreferenceStore csvnode = new ScopedPreferenceStore( InstanceScope.INSTANCE, CSVPreferences.P_NODE );
        
        Double startTime =  csvnode.getDouble(CSVPreferences.P_CSV_START_TIME);
        Double timeStep =  csvnode.getDouble(CSVPreferences.P_CSV_TIME_STEP);
        String decimalSeparator = csvnode.getString(CSVPreferences.P_CSV_DECIMAL_SEPARATOR);
        String columnSeparator = StringEscapeUtils.unescape( csvnode.getString(CSVPreferences.P_CSV_COLUMN_SEPARATOR) );
        Boolean resample = csvnode.getBoolean(CSVPreferences.P_CSV_RESAMPLE);
        String samplingModePreference = csvnode.getString(CSVPreferences.P_CSV_SAMPLING_MODE);
        int timeDigits = csvnode.getInt(CSVPreferences.P_CSV_TIME_DIGITS);
        int floatDigits = csvnode.getInt(CSVPreferences.P_CSV_FLOAT_DIGITS);
        int doubleDigits = csvnode.getInt(CSVPreferences.P_CSV_DOUBLE_DIGITS);
        
    	initialSelection =  ISelectionUtils.getPossibleKeys(exportModel.selection, SelectionHints.KEY_MAIN, Resource.class);

        models = exportModel.sessionContext.getSession().syncRequest(new UniqueRead<List<Pair<NamedResource,List<NamedResource>>>>() {

			@Override
			public List<Pair<NamedResource,List<NamedResource>>> perform(ReadGraph graph) throws DatabaseException {
				Layer0 L0 = Layer0.getInstance(graph);
				ModelingResources MOD = ModelingResources.getInstance(graph);
				List<Pair<NamedResource,List<NamedResource>>> result = new ArrayList<>();
				for(Resource model : graph.syncRequest(new org.simantics.db.layer0.request.ProjectModels(Simantics.getProjectResource()))) {
					String name = graph.getPossibleRelatedValue(model, L0.HasName, Bindings.STRING);
					if(name == null) continue;
					name = NameLabelUtil.modalName(graph, model);
					List<NamedResource> subs = new ArrayList<>();
					for(Resource item : ModelingUtils.searchByType(graph, model, MOD.Subscription_Item)) {
						String subscriptionLabel = null;
						Resource subscription = graph.getPossibleObject(item, L0.PartOf);
						if(subscription != null) {
							subscriptionLabel = graph.getPossibleRelatedValue(subscription, L0.HasLabel, Bindings.STRING);
						}
						SubscriptionItemLabelRule rule = new SubscriptionItemLabelRule();
						Map<String,String> map = rule.getLabel(graph, item); 
						String label = map.get(ColumnKeys.SINGLE);
						if(label == null) continue;
						if(subscriptionLabel != null) label = subscriptionLabel + "/" + label;
						subs.add(new NamedResource(label, item));
					}
					subs.sort((o1,o2) -> AlphanumComparator.CASE_INSENSITIVE_COMPARATOR.compare(o1.getName(), o2.getName()));
					result.add(new Pair<>(new NamedResource(name, model), subs));
				}
				return result;
			}
        	
        });
        
        Set<NamedResource> selected = exportModel.sessionContext.getSession().syncRequest(new UniqueRead<Set<NamedResource>>() {

			@Override
			public Set<NamedResource> perform(ReadGraph graph) throws DatabaseException {

				if(initialSelection == null) return Collections.emptySet();

				HashSet<NamedResource> result = new HashSet<>();
				
				for(Pair<NamedResource,List<NamedResource>> p : models) {
	            	for(NamedResource nr : p.second) {
	            		for(Resource i : initialSelection) {
		            		if(graph.syncRequest(new IsParent(i, nr.getResource()))) result.add(nr);
	            		}
	            	}
				}
				return result;
			}
        	
        });
 

        for(int i=0;i<models.size();i++) {
        	
        	Pair<NamedResource,List<NamedResource>> p = models.get(i);
            model.add(p.first.getName());

            boolean hasInitial = false;
            for(NamedResource nr : p.second) {
            	if(selected.contains(nr)) hasInitial = true;
            }
            if(hasInitial) {
            	model.select(i);
            	item.removeAll();
            	exportModel.models.clear();
            	int index = 0;
            	int firstIndex = 0;
            	for(NamedResource nr : p.second) {
            		TableItem ti = new TableItem(item, SWT.NONE);
            		ti.setText(nr.getName());
            		ti.setData(nr);
            		if(selected.contains(nr)) {
            			exportModel.models.add(nr);
            			ti.setChecked(true);
            			if(firstIndex == 0) firstIndex = index;
            		}
            		index++;
            	}
            	item.setTopIndex(firstIndex);
            	item.setData(p.first);
            }
            
        }
        
        this.decimalSeparator.select(DecimalSeparator.fromPreference(decimalSeparator).ordinal());
        this.columnSeparator.select(ColumnSeparator.fromPreference(columnSeparator).ordinal());
        
        if(resample) {
        	this.sampling.select(1);
        } else {
        	this.sampling.select(0);
        }
        
        this.samplingMode.select(ExportInterpolation.fromPreference(samplingModePreference).index());
        
        this.startTime.setText("" + startTime);
        this.timeStep.setText("" + timeStep);
        this.timeStamps.setText("" + timeDigits);
        this.singlePrecision.setText("" + floatDigits);
        this.doublePrecision.setText("" + doubleDigits);
        
        for (String path : exportModel.recentLocations) {
            exportLocation.add(path);
        }
        if (exportLocation.getItemCount() > 0)
            exportLocation.select(0);
        
    }

    Integer validInteger(String s) {
    	try {
    		return Integer.parseInt(s);
    	} catch (NumberFormatException e) {
    		return null;
    	}
    }

    Double validDouble(String s) {
    	try {
    		return Double.parseDouble(s);
    	} catch (NumberFormatException e) {
    		return null;
    	}
    }
    
    Pair<NamedResource,List<NamedResource>> getModel(String name) {
    	for(Pair<NamedResource,List<NamedResource>> data : models) {
    		if(data.first.getName().equals(name)) return data;
    	}
    	return null;
    }
    
    void validatePage() {

    	boolean resample = sampling.getText().equals("Resampled"); 
    	
    	if(resample) {
    		resampling.setText("Resampling settings");
    		timeStep.setEnabled(true);
    		startTime.setEnabled(true);
    		samplingMode.setEnabled(true);
    	} else {
    		resampling.setText("Resampling settings (not used with recorded samples)");
    		timeStep.setEnabled(false);
    		startTime.setEnabled(false);
    		samplingMode.setEnabled(false);
    	}
    	
    	String selectedModel = model.getText();
    	Pair<NamedResource,List<NamedResource>> p = getModel(selectedModel);
    	if(p != null) {
    		
    		HashSet<NamedResource> checked = new HashSet<>();
    		
    		NamedResource existing = (NamedResource)item.getData();
    		if(!p.first.equals(existing)) {
    		
	    		item.removeAll();
	    		for(NamedResource nr : p.second) {
	    			TableItem ti = new TableItem(item, SWT.NONE);
	    			ti.setText(nr.getName());
	    			ti.setData(nr);
	    		}
	    		item.setData(p.first);
	    		
    		}
    		
    		for(TableItem ti : item.getItems()) {
    			if(ti.getChecked()) checked.add((NamedResource)ti.getData());
    		}
    		
    		exportModel.models = checked;
    		
    	}

    	Double validStartTime = validDouble(startTime.getText());
    	Double validStepSize = validDouble(timeStep.getText());

    	if(resample) {
    		
            if(validStartTime == null) {
                setErrorMessage("Start time must be a number.");
                setPageComplete(false);
                return;
            }
            
            if(validStepSize == null) {
                setErrorMessage("Step size must be a number.");
                setPageComplete(false);
                return;
            }
            if(validStepSize <= 0) {
                setErrorMessage("Step size must be greater than 0.");
                setPageComplete(false);
                return;
            }

    	} else {
    		
    		if(exportModel.models.size() > 1) {
                setErrorMessage("Recorded samples can only be exported for a single subscription item.");
                setPageComplete(false);
                return;
    		}

    	}
    	
    	if(item.getItemCount() == 0) {
            setErrorMessage("No subscription items in selected model.");
            setPageComplete(false);
            return;
    	}
    	
        if (exportModel.models.isEmpty()) {
            setErrorMessage("No items selected for export.");
            setPageComplete(false);
            return;
        }
        
        String exportLoc = exportLocation.getText();
        if (exportLoc.isEmpty()) {
            setErrorMessage("Select output file.");
            setPageComplete(false);
            return;
        }
        File file = new File(exportLoc);
        if (file.isDirectory()) {
            setErrorMessage("The output file is a directory.");
            setPageComplete(false);
            return;
        }
        File parent = file.getParentFile();
        if (parent == null || !parent.isDirectory()) {
            setErrorMessage("The output directory does not exist.");
            setPageComplete(false);
            return;
        }

        exportModel.columnSeparator = ColumnSeparator.fromIndex(columnSeparator.getSelectionIndex());
        exportModel.decimalSeparator = DecimalSeparator.fromIndex(decimalSeparator.getSelectionIndex());
        if (exportModel.columnSeparator.preference.equals(exportModel.decimalSeparator.preference)) {
            setErrorMessage("Decimal and column separator cannot be the same character.");
            setPageComplete(false);
            return;
        }

        Integer validTimeDigits = validInteger(timeStamps.getText());

        if(validTimeDigits == null) {
            setErrorMessage("Time stamps needs to be an integer number.");
            setPageComplete(false);
            return;
        }

        Integer validSinglePrecision = validInteger(singlePrecision.getText());
        if(validSinglePrecision == null) {
            setErrorMessage("Single precision needs to be an integer number.");
            setPageComplete(false);
            return;
        }

        Integer validDoublePrecision = validInteger(doublePrecision.getText());
        if(validDoublePrecision == null) {
            setErrorMessage("Double precision needs to be an integer number.");
            setPageComplete(false);
            return;
        }

        exportModel.exportLocation = file;
        exportModel.overwrite = overwrite.getSelection();

        exportModel.startTime = validStartTime;
        exportModel.timeStep = validStepSize;

        exportModel.resample = sampling.getSelectionIndex() == 1;
        exportModel.samplingMode = ExportInterpolation.fromIndex(samplingMode.getSelectionIndex());
        
        exportModel.timeDigits = validTimeDigits;
        exportModel.floatDigits = validSinglePrecision;
        exportModel.doubleDigits = validDoublePrecision;
        
        setErrorMessage(null);
        setMessage("Press Finish to export subscription data.");
        setPageComplete(true);
        
    }

}