/**
 * SQL-DK
 * Copyright © 2013 František Kučera (frantovo.cz)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package info.globalcode.sql.dk.formatting;

import info.globalcode.sql.dk.Parameter;
import info.globalcode.sql.dk.Xmlns;
import info.globalcode.sql.dk.configuration.DatabaseDefinition;
import static info.globalcode.sql.dk.Functions.notNull;
import info.globalcode.sql.dk.NamedParameter;
import info.globalcode.sql.dk.configuration.PropertyDeclaration;
import static info.globalcode.sql.dk.formatting.AbstractXmlFormatter.qname;
import java.sql.Array;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.SQLXML;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.xml.namespace.QName;

/**
 * <p>
 * Prints machine-readable output – XML document containing resultsets and updates count. Good
 * choice for further processing – e.g. XSL transformation.</p>
 *
 * <p>
 * TODO: XSD</p>
 *
 * @author Ing. František Kučera (frantovo.cz)
 */
@PropertyDeclaration(name = XmlFormatter.PROPERTY_LABELED_COLUMNS, defaultValue = "false", type = Boolean.class, description = "whether to add 'label' attribute to each 'column' element")
public class XmlFormatter extends AbstractXmlFormatter {

	public static final String NAME = "xml"; // bash-completion:formatter
	public static final String PROPERTY_LABELED_COLUMNS = "labeledColumns";
	private static final Logger log = Logger.getLogger(XmlFormatter.class.getName());
	private final boolean labeledColumns;

	public XmlFormatter(FormatterContext formatterContext) {
		super(formatterContext);
		labeledColumns = formatterContext.getProperties().getBoolean(PROPERTY_LABELED_COLUMNS, false);
	}

	@Override
	public void writeStartBatch() {
		super.writeStartBatch();
		printStartDocument();
		printStartElement(qname("batchResult"), singleAttribute(qname("xmlns"), Xmlns.BATCH_RESULT));
	}

	@Override
	public void writeEndBatch() {
		super.writeEndBatch();
		printEndElement();
		printEndDocument();
	}

	@Override
	public void writeStartDatabase(DatabaseDefinition databaseDefinition) {
		super.writeStartDatabase(databaseDefinition);
		Map<QName, String> attributes = databaseDefinition.getName() == null ? null : singleAttribute(qname("name"), databaseDefinition.getName());
		printStartElement(qname("database"), attributes);
	}

	@Override
	public void writeEndDatabase() {
		super.writeEndDatabase();
		printEndElement();
	}

	@Override
	public void writeStartStatement() {
		super.writeStartStatement();
		printStartElement(qname("statement"));
	}

	@Override
	public void writeEndStatement() {
		super.writeEndStatement();
		printEndElement();
	}

	@Override
	public void writeQuery(String sql) {
		super.writeQuery(sql);
		printTextElement(qname("sql"), null, sql);
	}

	@Override
	public void writeParameters(List<? extends Parameter> parameters) {
		super.writeParameters(parameters);

		for (Parameter p : notNull(parameters)) {

			Map<QName, String> attributes = new LinkedHashMap<>(2);
			if (p instanceof NamedParameter) {
				attributes.put(qname("name"), ((NamedParameter) p).getName());
			}
			attributes.put(qname("type"), p.getType().name());

			printTextElement(qname("parameter"), attributes, String.valueOf(p.getValue()));
		}

	}

	@Override
	public void writeStartResultSet(ColumnsHeader header) {
		super.writeStartResultSet(header);
		printStartElement(qname("resultSet"));

		for (ColumnDescriptor cd : header.getColumnDescriptors()) {
			Map<QName, String> attributes = new LinkedHashMap<>(4);
			attributes.put(qname("label"), cd.getLabel());
			attributes.put(qname("name"), cd.getName());
			attributes.put(qname("typeName"), cd.getTypeName());
			attributes.put(qname("type"), String.valueOf(cd.getType()));
			printEmptyElement(qname("columnHeader"), attributes);
		}
	}

	@Override
	public void writeEndResultSet() {
		super.writeEndResultSet();
		printEndElement();
	}

	@Override
	public void writeStartRow() {
		super.writeStartRow();
		printStartElement(qname("row"));
	}

	@Override
	public void writeColumnValue(Object value) {
		super.writeColumnValue(value);

		Map<QName, String> attributes = null;
		if (labeledColumns) {
			attributes = new LinkedHashMap<>(2);
			attributes.put(qname("label"), getCurrentColumnsHeader().getColumnDescriptors().get(getCurrentColumnsCount() - 1).getLabel());
		}

		if (value == null) {
			if (attributes == null) {
				attributes = new LinkedHashMap<>(2);
			}
			attributes.put(qname("null"), "true");
			printEmptyElement(qname("column"), attributes);
		} else if (value instanceof Array) {

			Array sqlArray = (Array) value;
			try {
				Object[] array = (Object[]) sqlArray.getArray();
				printStartElement(qname("column"), attributes);
				printArray(array);
				printEndElement();
			} catch (SQLException e) {
				// FIXME: rewrite array formatting, remember array mode, don't try sqlArray.getArray() again and again if it has failed
				log.log(Level.SEVERE, "Unable to format array", e);
				try {
					ResultSet arrayResultSet = sqlArray.getResultSet();
					//int columnCount = arrayResultSet.getMetaData().getColumnCount();
					ArrayList<Object> arrayList = new ArrayList<>();
					while (arrayResultSet.next()) {
						arrayList.add(arrayResultSet.getObject(2));
						// for (int i = 1; i <= columnCount; i++) {
						// 	log.log(Level.INFO, "Array column {0} = {1}", new Object[]{i, arrayResultSet.getObject(i)});
						// }
					}

					printStartElement(qname("column"), attributes);
					// FIXME: instanceof SQLXML, see below
					printArray(arrayList.toArray());
					printEndElement();

				} catch (SQLException e2) {
					// FIXME: fix logging, error recovery
					log.log(Level.SEVERE, "Second level fuck up !!!", e2);
				}

				writeColumnValue(String.valueOf(value));
			}

		} else if (value instanceof SQLXML) { // FIXME: move to separate method, to AbstractFormatter?
			SQLXML xml = (SQLXML) value;
			// TODO: parse DOM/SAX and transplant XML, don't escape (optional)
			try {
				printTextElement(qname("column"), attributes, xml.getString());
			} catch (SQLException e) {
				log.log(Level.SEVERE, "Unable to format XML", e);
				writeColumnValue(String.valueOf(value));
			}
		} else {
			printTextElement(qname("column"), attributes, toString(value));
		}
	}

	private void printArray(Object[] array) {
		printStartElement(qname("array"));
		for (Object o : array) {
			if (o instanceof Object[]) {
				printStartElement(qname("item"));
				printArray((Object[]) o);
				printEndElement();
			} else {
				printTextElement(qname("item"), null, String.valueOf(o));
			}
		}
		printEndElement();
	}

	@Override
	public void writeEndRow() {
		super.writeEndRow();
		printEndElement();
	}

	@Override
	public void writeUpdatesResult(int updatedRowsCount) {
		super.writeUpdatesResult(updatedRowsCount);
		printTextElement(qname("updatedRows"), null, String.valueOf(updatedRowsCount));
	}

	protected String toString(Object value) {
		return String.valueOf(value);
	}
}