/**

 * 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.ColorfulPrintWriter;

import static info.globalcode.sql.dk.ColorfulPrintWriter.*;

import static info.globalcode.sql.dk.Functions.lpad;

import static info.globalcode.sql.dk.Functions.rpad;

import static info.globalcode.sql.dk.Functions.repeat;

import java.util.List;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

/**

 * <p>Prints human-readable output – tables of result sets and text messages with update counts.</p>

 *

 * <p>Longer values might break the table – overflow the cells – see alternative tabular formatters

 * and the {@linkplain #PROPERTY_TRIM} property.</p>

 *

 * @author Ing. František Kučera (frantovo.cz)

 * @see TabularPrefetchingFormatter

 * @see TabularWrappingFormatter

 */

public class TabularFormatter extends AbstractFormatter {

	public static final String NAME = "tabular"; // bash-completion:formatter

	private static final String HEADER_TYPE_PREFIX = " (";

	private static final String HEADER_TYPE_SUFFIX = ")";

	public static final String PROPERTY_ASCII = "ascii";

	public static final String PROPERTY_COLORFUL = "color";

	public static final String PROPERTY_TRIM = "trim";

	private static final Pattern whitespaceToReplace = Pattern.compile("\\n|\\t");

	protected ColorfulPrintWriter out;

	private boolean firstResult = true;

	private int[] columnWidth;

	/**

	 * use ASCII borders instead of unicode ones

	 */

	private final boolean asciiNostalgia;

	/**

	 * Trim values if they are longer than cell size

	 */

	private final boolean trimValues;

	public TabularFormatter(FormatterContext formatterContext) {

		super(formatterContext);

		out = new ColorfulPrintWriter(formatterContext.getOutputStream());

		asciiNostalgia = formatterContext.getProperties().getBoolean(PROPERTY_ASCII, false);

		trimValues = formatterContext.getProperties().getBoolean(PROPERTY_TRIM, false);

		out.setColorful(formatterContext.getProperties().getBoolean(PROPERTY_COLORFUL, true));

	}

	@Override

	public void writeStartResultSet(ColumnsHeader header) {

		super.writeStartResultSet(header);

		printResultSeparator();

		initColumnWidths(header.getColumnCount());

		printTableIndent();

		printTableBorder("╭");

		List<ColumnDescriptor> columnDescriptors = header.getColumnDescriptors();

		for (ColumnDescriptor cd : columnDescriptors) {

			// padding: make header cell at least same width as data cells in this column

			int typeWidth = cd.getTypeName().length() + HEADER_TYPE_PREFIX.length() + HEADER_TYPE_SUFFIX.length();

			cd.setLabel(rpad(cd.getLabel(), getColumnWidth(cd.getColumnNumber()) - typeWidth));

			updateColumnWidth(cd.getColumnNumber(), cd.getLabel().length() + typeWidth);

			if (!cd.isFirstColumn()) {

				printTableBorder("┬");

			}

			printTableBorder(repeat('─', getColumnWidth(cd.getColumnNumber()) + 2));

		}

		printTableBorder("╮");

		out.println();

		for (ColumnDescriptor cd : columnDescriptors) {

			if (cd.isFirstColumn()) {

				printTableIndent();

				printTableBorder("│ ");

			} else {

				printTableBorder(" │ ");

			}

			out.print(TerminalStyle.Bright, cd.getLabel());

			out.print(HEADER_TYPE_PREFIX);

			out.print(cd.getTypeName());

			out.print(HEADER_TYPE_SUFFIX);

			if (cd.isLastColumn()) {

				printTableBorder(" │");

			}

		}

		out.println();

		printTableIndent();

		printTableBorder("├");

		for (int i = 1; i <= header.getColumnCount(); i++) {

			if (i > 1) {

				printTableBorder("┼");

			}

			printTableBorder(repeat('─', getColumnWidth(i) + 2));

		}

		printTableBorder("┤");

		out.println();

		out.flush();

	}

	/**

	 * Must be called before

	 * {@linkplain #updateColumnWidth(int, int)}

	 * and {@linkplain #getColumnWidth(int)}

	 * for each result set.

	 *

	 * @param columnCount number of columns in current result set

	 */

	protected void initColumnWidths(int columnCount) {

		if (columnWidth == null) {

			columnWidth = new int[columnCount];

		}

	}

	protected void cleanColumnWidths() {

		columnWidth = null;

	}

	@Override

	public void writeColumnValue(Object value) {

		super.writeColumnValue(value);

		writeColumnValueInternal(value);

	}

	protected void writeColumnValueInternal(Object value) {

		if (isCurrentColumnFirst()) {

			printTableIndent();

			printTableBorder("│ ");

		} else {

			printTableBorder(" │ ");

		}

		String valueString = toString(value);

		printValueWithWhitespaceReplaced(valueString);

		if (isCurrentColumnLast()) {

			printTableBorder(" │");

		}

	}

	protected int getColumnWidth(int columnNumber) {

		return columnWidth[columnNumber - 1];

	}

	private void setColumnWidth(int columnNumber, int width) {

		columnWidth[columnNumber - 1] = width;

	}

	protected void updateColumnWidth(int columnNumber, int width) {

		int oldWidth = getColumnWidth(columnNumber);

		setColumnWidth(columnNumber, Math.max(width, oldWidth));

	}

	protected String toString(Object value) {

		final int width = getColumnWidth(getCurrentColumnsCount());

		String result;

		if (value instanceof Number || value instanceof Boolean) {

			result = lpad(String.valueOf(value), width);

		} else {

			result = rpad(String.valueOf(value), width);

		}

		// ?	value = (boolean) value ? "✔" : "✗";

		if (trimValues && result.length() > width) {

			result = result.substring(0, width - 1) + "…";

		}

		return result;

	}

	@Override

	public void writeEndRow() {

		super.writeEndRow();

		writeEndRowInternal();

	}

	public void writeEndRowInternal() {

		out.println();

		out.flush();

	}

	@Override

	public void writeEndResultSet() {

		int columnCount = getCurrentColumnsHeader().getColumnCount();

		super.writeEndResultSet();

		printTableIndent();

		printTableBorder("╰");

		for (int i = 1; i <= columnCount; i++) {

			if (i > 1) {

				printTableBorder("┴");

			}

			printTableBorder(repeat('─', getColumnWidth(i) + 2));

		}

		printTableBorder("╯");

		out.println();

		cleanColumnWidths();

		out.print(TerminalColor.Yellow, "Record count: ");

		out.println(getCurrentRowCount());

		out.bell();

		out.flush();

	}

	@Override

	public void writeUpdatesResult(int updatedRowsCount) {

		super.writeUpdatesResult(updatedRowsCount);

		printResultSeparator();

		out.print(TerminalColor.Red, "Updated records: ");

		out.println(updatedRowsCount);

		out.bell();

		out.flush();

	}

	@Override

	public void writeEndDatabase() {

		super.writeEndDatabase();

		out.flush();

	}

	private void printResultSeparator() {

		if (firstResult) {

			firstResult = false;

		} else {

			out.println();

		}

	}

	protected void printTableBorder(String border) {

		if (asciiNostalgia) {

			border = border.replaceAll("─", "-");

			border = border.replaceAll("│", "|");

			border = border.replaceAll("[╭┬╮├┼┤╰┴╯]", "+");

		}

		out.print(TerminalColor.Green, border);

	}

	protected void printTableIndent() {

		out.print(" ");

	}

	protected void printValueWithWhitespaceReplaced(String valueString) {

		Matcher m = whitespaceToReplace.matcher(valueString);

		int start = 0;

		while (m.find(start)) {

			out.print(TerminalColor.Cyan, valueString.substring(start, m.start()));

			switch (m.group()) {

				case "\n":

					out.print(TerminalColor.Red, "↲");

					break;

				case "\t":

					out.print(TerminalColor.Red, "↹");

					break;

				default:

					throw new IllegalStateException("Unexpected whitespace token: „" + m.group() + "“");

			}

			start = m.end();

		}

		out.print(TerminalColor.Cyan, valueString.substring(start, valueString.length()));

	}

}