package org.simantics.simulation.export;

import java.io.File;
import java.io.IOException;
import java.text.DecimalFormatSymbols;
import java.util.Collections;
import java.util.List;
import java.util.Locale;

import org.eclipse.core.runtime.preferences.InstanceScope;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.ui.preferences.ScopedPreferenceStore;
import org.osgi.service.prefs.Preferences;
import org.simantics.databoard.Accessors;
import org.simantics.databoard.Bindings;
import org.simantics.databoard.Datatypes;
import org.simantics.databoard.accessor.RecordAccessor;
import org.simantics.databoard.accessor.error.AccessorConstructionException;
import org.simantics.databoard.accessor.error.AccessorException;
import org.simantics.databoard.accessor.reference.ChildReference;
import org.simantics.databoard.binding.mutable.Variant;
import org.simantics.databoard.type.Datatype;
import org.simantics.databoard.type.DoubleType;
import org.simantics.databoard.type.RecordType;
import org.simantics.export.core.ExportContext;
import org.simantics.export.core.error.ExportException;
import org.simantics.export.core.intf.FormatClass;
import org.simantics.export.core.manager.Content;
import org.simantics.history.HistoryException;
import org.simantics.history.csv.ColumnSeparator;
import org.simantics.history.csv.DecimalSeparator;

/**
 * This class represents the CSV (Comma Separated Value) file format.
 *
 * @author toni.kalajainen@semantum.fi
 */
public class CSVFormat implements FormatClass {

	// Accessor paths
	public static ChildReference P_CSV_COLUMN_SEPARATOR = ChildReference.parsePath("Comma Separated Value (CSV)/Column Separator");
	public static ChildReference P_CSV_DECIMAL_SEPARATOR = ChildReference.parsePath("Comma Separated Value (CSV)/Decimal Separator");
	public static ChildReference P_CSV_TIME_STEP = ChildReference.parsePath("Comma Separated Value (CSV)/Time Step");	
	
	static RecordType options;
    static RecordType csvOptions;
    
    static {
	    Datatype second = new DoubleType("s");
    	
    	csvOptions = new RecordType();
        csvOptions.addComponent("Time Step", second);
        csvOptions.addComponent("Column Separator", Datatypes.STRING);
        csvOptions.addComponent("Decimal Separator", Datatypes.STRING);

        options = new RecordType();
        options.addComponent("Comma Separated Value (CSV)", csvOptions);
    }
	
	@Override
	public RecordType options(ExportContext context)
	throws ExportException {
		return options;
	}

	@Override
	public List<String> validate(ExportContext context, Variant options) throws ExportException {
		return Collections.emptyList();
	}
	

	@Override
	public void fillDefaultPrefs( ExportContext ctx, Variant options ) throws ExportException {
		// 1. Figure out suitable default values
        IPreferenceStore csvnode = new ScopedPreferenceStore( InstanceScope.INSTANCE, CSVPreferences.P_NODE );
        
        Double timeStep = CSVPreferences.DEFAULT_CSV_TIME_STEP;
        String decimalSeparator = ".";
        String columnSeparator = "\t";
        
        Locale locale = Locale.getDefault();
        DecimalFormatSymbols symbols = DecimalFormatSymbols.getInstance( locale );
        decimalSeparator = symbols.getDecimalSeparator()+""; 
        columnSeparator = decimalSeparator.equals(",")?"\\t":",";

        if (csvnode != null) {
        	if ( csvnode.contains(CSVPreferences.P_CSV_TIME_STEP) ) timeStep = csvnode.getDouble(CSVPreferences.P_CSV_TIME_STEP);
        	if ( csvnode.contains(CSVPreferences.P_CSV_DECIMAL_SEPARATOR) ) decimalSeparator = csvnode.getString(CSVPreferences.P_CSV_DECIMAL_SEPARATOR);
        	if ( csvnode.contains(CSVPreferences.P_CSV_COLUMN_SEPARATOR) ) columnSeparator = csvnode.getString(CSVPreferences.P_CSV_COLUMN_SEPARATOR);
        }
		
        // 2. Write default values
        try {
			RecordAccessor ra = Accessors.getAccessor(options);
			ra.setValue(P_CSV_COLUMN_SEPARATOR, Bindings.STRING, columnSeparator);
			ra.setValue(P_CSV_DECIMAL_SEPARATOR, Bindings.STRING, decimalSeparator);
			ra.setValue(P_CSV_TIME_STEP, Bindings.DOUBLE, timeStep);
			
		} catch (AccessorConstructionException e) {
			throw new ExportException(e);
		} catch (AccessorException e) {
			throw new ExportException(e);
		}
	}

	@Override
	public void savePref(Variant options, Preferences contentScopeNode, Preferences workbenchScopeNode) throws ExportException {
		try {
			RecordAccessor ra = Accessors.getAccessor(options);
			
			String columnSeparator = (String) ra.getValue( P_CSV_COLUMN_SEPARATOR, Bindings.STRING );
			if ( columnSeparator != null ) workbenchScopeNode.put(CSVPreferences.P_CSV_COLUMN_SEPARATOR, columnSeparator);			
			
			String decimalSeparator = (String) ra.getValue(P_CSV_DECIMAL_SEPARATOR, Bindings.STRING );
			if ( decimalSeparator != null ) workbenchScopeNode.put(CSVPreferences.P_CSV_DECIMAL_SEPARATOR, decimalSeparator);			
			
			Double timeStep = (Double) ra.getValue(P_CSV_TIME_STEP, Bindings.DOUBLE );
			if ( timeStep != null ) contentScopeNode.putDouble(CSVPreferences.P_CSV_TIME_STEP, timeStep);			

		} catch (AccessorConstructionException e) {
			throw new ExportException(e);
		} catch (AccessorException e) {
			throw new ExportException(e);
		}		
	}

	@Override
	public void loadPref(Variant options, Preferences contentScopeNode, Preferences workbenchScopeNode) throws ExportException {
		try {
			RecordAccessor ra = Accessors.getAccessor(options);
			
			String columnSeparator = workbenchScopeNode.get(CSVPreferences.P_CSV_COLUMN_SEPARATOR, null);
			if ( columnSeparator != null ) ra.setValue(P_CSV_COLUMN_SEPARATOR, Bindings.STRING, columnSeparator );			
			
			String decimalSeparator = workbenchScopeNode.get(CSVPreferences.P_CSV_DECIMAL_SEPARATOR, null);
			if ( decimalSeparator != null ) ra.setValue(P_CSV_DECIMAL_SEPARATOR, Bindings.STRING, decimalSeparator );
			
			Double timeStep = contentScopeNode.getDouble(CSVPreferences.P_CSV_TIME_STEP, 0);
			if ( timeStep != null ) ra.setValue(P_CSV_TIME_STEP, Bindings.DOUBLE, timeStep );			

		} catch (AccessorConstructionException e) {
			throw new ExportException(e);
		} catch (AccessorException e) {
			throw new ExportException(e);
		}		
	}
	
	@Override
	public Object createFile(ExportContext context, File outputFile, Variant options) throws ExportException {
		CSVWriter writer = new CSVWriter();
		writer.file = outputFile;

		try {
			/// Read configurations 
			RecordAccessor ra = Accessors.getAccessor(options);
				
			// Start, End time
			Double startTime = (Double) ra.getValue( ExperimentExportClass.P_EXPERIMENT_START, Bindings.DOUBLE );
			Double endTime = (Double) ra.getValue( ExperimentExportClass.P_EXPERIMENT_END, Bindings.DOUBLE );
			writer.setTimeRange(startTime, endTime);
	        
	        // Separators
			String columnSeparator = (String) ra.getValue( CSVFormat.P_CSV_COLUMN_SEPARATOR, Bindings.STRING );
			writer.setColumnSeparator(ColumnSeparator.fromPreference(columnSeparator));
			
			String decimalSeparator = (String) ra.getValue( CSVFormat.P_CSV_DECIMAL_SEPARATOR, Bindings.STRING );
			writer.setDecimalSeparator(DecimalSeparator.fromPreference(decimalSeparator));
			
			Double timeStep = (Double) ra.getValue( CSVFormat.P_CSV_TIME_STEP, Bindings.DOUBLE );
			writer.setTimeStep(timeStep);
			
		} catch (AccessorConstructionException e) {
			throw new ExportException(e);
		} catch (AccessorException e) {
			throw new ExportException(e);
		}		
		
		return writer;
	}

	@Override
	public Object openFile(ExportContext context, File inputFile, Variant options) throws ExportException {
		throw new ExportException("Not implemented");
	}

	@Override
	public void closeFile(ExportContext context, Object handle_) throws ExportException {
		CSVWriter handle = (CSVWriter) handle_;
		try {
			handle.write();
		} catch (IOException e) {
			throw new ExportException(e);
		} catch (HistoryException e) {
			throw new ExportException(e);
		}
	}
	
	@Override
	public void addAttachment(ExportContext context, Object handle, List<Content> attachments) throws ExportException {
		throw new ExportException( "Cannot add attachments to a CSV file." );
	}

}