/*
 * Copyright 2004-2011 H2 Group.
 * Copyright 2011 James Moger.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.iciql.util;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.Writer;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import com.iciql.Db;
import com.iciql.DbInspector;

/**
 * Generates iciql models.
 */
public class GenerateModels {

	/**
	 * The output stream where this tool writes to.
	 */
	protected PrintStream out = System.out;

	public static void main(String... args) {
		GenerateModels tool = new GenerateModels();
		try {
			tool.runTool(args);
		} catch (SQLException e) {
			tool.out.print("Error: ");
			tool.out.println(e.getMessage());
			tool.out.println();
			tool.showUsage();
		}
	}

	public void runTool(String... args) throws SQLException {
		String url = null;
		String user = "sa";
		String password = "";
		String schema = null;
		String table = null;
		String packageName = "";
		String folder = null;
		boolean annotateSchema = true;
		boolean trimStrings = false;
		for (int i = 0; args != null && i < args.length; i++) {
			String arg = args[i];
			if (arg.equals("-url")) {
				url = args[++i];
			} else if (arg.equals("-user")) {
				user = args[++i];
			} else if (arg.equals("-password")) {
				password = args[++i];
			} else if (arg.equals("-schema")) {
				schema = args[++i];
			} else if (arg.equals("-table")) {
				table = args[++i];
			} else if (arg.equals("-package")) {
				packageName = args[++i];
			} else if (arg.equals("-folder")) {
				folder = args[++i];
			} else if (arg.equals("-annotateSchema")) {
				try {
					annotateSchema = Boolean.parseBoolean(args[++i]);
				} catch (Throwable t) {
					throw new SQLException("Can not parse -annotateSchema value");
				}
			} else if (arg.equals("-trimStrings")) {
				try {
					trimStrings = Boolean.parseBoolean(args[++i]);
				} catch (Throwable t) {
					throw new SQLException("Can not parse -trimStrings value");
				}
			} else {
				throwUnsupportedOption(arg);
			}
		}
		if (url == null) {
			throw new SQLException("URL not set");
		}
		execute(url, user, password, schema, table, packageName, folder, annotateSchema, trimStrings);
	}

	/**
	 * Generates models from the database.
	 * 
	 * @param url
	 *            the database URL
	 * @param user
	 *            the user name
	 * @param password
	 *            the password
	 * @param schema
	 *            the schema to read from. null for all schemas.
	 * @param table
	 *            the table to model. null for all tables within schema.
	 * @param packageName
	 *            the package name of the model classes.
	 * @param folder
	 *            destination folder for model classes (package path not
	 *            included)
	 * @param annotateSchema
	 *            includes the schema in the table model annotations
	 * @param trimStrings
	 *            automatically trim strings that exceed maxLength
	 */
	public static void execute(String url, String user, String password, String schema, String table,
			String packageName, String folder, boolean annotateSchema, boolean trimStrings)
			throws SQLException {
		Connection conn = null;
		try {
			conn = DriverManager.getConnection(url, user, password);
			Db db = Db.open(url, user, password.toCharArray());
			DbInspector inspector = new DbInspector(db);
			List<String> models = inspector.generateModel(schema, table, packageName, annotateSchema,
					trimStrings);
			File parentFile;
			if (StringUtils.isNullOrEmpty(folder)) {
				parentFile = new File(System.getProperty("user.dir"));
			} else {
				parentFile = new File(folder);
			}
			parentFile.mkdirs();
			Pattern p = Pattern.compile("class ([a-zA-Z0-9]+)");
			for (String model : models) {
				Matcher m = p.matcher(model);
				if (m.find()) {
					String className = m.group().substring("class".length()).trim();
					File classFile = new File(parentFile, className + ".java");
					Writer o = new FileWriter(classFile, false);
					PrintWriter writer = new PrintWriter(new BufferedWriter(o));
					writer.write(model);
					writer.close();
					System.out.println("Generated " + classFile.getAbsolutePath());
				}
			}
		} catch (IOException io) {
			throw new SQLException("could not generate model", io);
		} finally {
			JdbcUtils.closeSilently(conn);
		}
	}

	/**
	 * Throw a SQLException saying this command line option is not supported.
	 * 
	 * @param option
	 *            the unsupported option
	 * @return this method never returns normally
	 */
	protected SQLException throwUnsupportedOption(String option) throws SQLException {
		showUsage();
		throw new SQLException("Unsupported option: " + option);
	}

	protected void showUsage() {
		out.println("GenerateModels");
		out.println("Usage:");
		out.println();
		out.println("(*) -url jdbc:h2:~test");
		out.println("    -user <string>");
		out.println("    -password <string>");
		out.println("    -schema <string>");
		out.println("    -table <string>");
		out.println("    -package <string>");
		out.println("    -folder <string>");
		out.println("    -annotateSchema <boolean>");
		out.println("    -trimStrings <boolean>");
	}

}