/**

  * 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;

 import info.globalcode.sql.dk.configuration.ConfigurationProvider;

 import info.globalcode.sql.dk.CLIOptions.MODE;

 import info.globalcode.sql.dk.batch.Batch;

 import info.globalcode.sql.dk.batch.BatchDecoder;

 import info.globalcode.sql.dk.batch.BatchException;

 import info.globalcode.sql.dk.batch.BatchEncoder;

 import info.globalcode.sql.dk.configuration.Configuration;

 import info.globalcode.sql.dk.configuration.ConfigurationException;

 import info.globalcode.sql.dk.configuration.DatabaseDefinition;

 import info.globalcode.sql.dk.configuration.FormatterDefinition;

 import info.globalcode.sql.dk.configuration.NameIdentified;

 import info.globalcode.sql.dk.formatting.Formatter;

 import info.globalcode.sql.dk.formatting.FormatterContext;

 import info.globalcode.sql.dk.formatting.FormatterException;

 import java.io.File;

 import java.io.FileNotFoundException;

 import java.io.IOException;

 import java.io.PrintStream;

 import java.io.PrintWriter;

 import java.sql.SQLException;

 import java.util.Collection;

 import java.util.logging.Level;

 import java.util.logging.LogRecord;

 import java.util.logging.Logger;

 import javax.xml.bind.JAXBContext;

 import javax.xml.bind.Unmarshaller;

 /**

  * Entry point of the command line interface of SQL-DK.

  *

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

  */

 public class CLIStarter implements ConfigurationProvider {

 	// help:exit-codes

 	public static final int EXIT_SUCCESS = 0; // doc:success

 	public static final int EXIT_UNEXPECTED_ERROR = 1; // doc:unexpected error (probably bug)

 	// 2 is reserved: http://www.tldp.org/LDP/abs/html/exitcodes.html#EXITCODESREF

 	public static final int EXIT_SQL_ERROR = 3; // doc:SQL error

 	public static final int EXIT_CLI_PARSE_ERROR = 4; // doc:CLI options parse error

 	public static final int EXIT_CLI_VALIDATE_ERROR = 5; // doc:CLI options validation error

 	public static final int EXIT_CONFIGURATION_ERROR = 6; // doc:configuration error

 	public static final int EXIT_FORMATTING_ERROR = 7; // doc:formatting error

 	public static final int EXIT_BATCH_ERROR = 8; // doc:batch error

 	private static final Logger log = Logger.getLogger(CLIStarter.class.getName());

 	private CLIOptions options;

 	private Configuration configuration;

 	public static void main(String[] args) {

 		log.log(Level.FINE, "Starting " + Constants.PROGRAM_NAME);

 		int exitCode;

 		if (args.length == 0) {

 			args = new String[]{CLIParser.Tokens.INFO_HELP};

 		}

 		try {

 			CLIParser parser = new CLIParser();

 			CLIOptions options = parser.parseOptions(args);

 			options.validate();

 			CLIStarter starter = new CLIStarter(options);

 			starter.installDefaultConfiguration();

 			starter.process();

 			log.log(Level.FINE, "All done");

 			exitCode = EXIT_SUCCESS;

 		} catch (CLIParserException e) {

 			log.log(Level.SEVERE, "Unable to parse CLI options", e);

 			exitCode = EXIT_CLI_PARSE_ERROR;

 		} catch (InvalidOptionsException e) {

 			log.log(Level.SEVERE, "Invalid CLI options", e);

 			for (InvalidOptionsException.OptionProblem p : e.getProblems()) {

 				LogRecord r = new LogRecord(Level.SEVERE, "Option problem: {0}");

 				r.setThrown(p.getException());

 				r.setParameters(new Object[]{p.getDescription()});

 				log.log(r);

 			}

 			exitCode = EXIT_CLI_VALIDATE_ERROR;

 		} catch (ConfigurationException e) {

 			log.log(Level.SEVERE, "Configuration problem", e);

 			exitCode = EXIT_CONFIGURATION_ERROR;

 		} catch (SQLException e) {

 			log.log(Level.SEVERE, "SQL problem", e);

 			exitCode = EXIT_SQL_ERROR;

 		} catch (FormatterException e) {

 			log.log(Level.SEVERE, "Formatting problem", e);

 			exitCode = EXIT_FORMATTING_ERROR;

 		} catch (BatchException e) {

 			log.log(Level.SEVERE, "Batch problem", e);

 			exitCode = EXIT_BATCH_ERROR;

 		}

 		System.exit(exitCode);

 	}

 	public CLIStarter(CLIOptions options) {

 		this.options = options;

 	}

 	private void process() throws ConfigurationException, SQLException, FormatterException, BatchException {

 		MODE mode = options.getMode();

 		/** Show info */

 		if (!options.getShowInfo().isEmpty()) {

 			PrintStream infoOut = mode == MODE.JUST_SHOW_INFO ? System.out : System.err;

 			InfoLister infoLister = new InfoLister(infoOut, this, options);

 			infoLister.showInfo();

 		}

 		switch (mode) {

 			case QUERY_NOW:

 				processQueryNow();

 				break;

 			case PREPARE_BATCH:

 				processPrepareBatch();

 				break;

 			case EXECUTE_BATCH:

 				processExecuteBatch();

 				break;

 			case JUST_SHOW_INFO:

 				// already done above

 				break;

 			default:

 				log.log(Level.SEVERE, "Unsupported mode: {0}", mode);

 				break;

 		}

 		generateBashCompletion();

 	}

 	private void processQueryNow() throws ConfigurationException, SQLException, FormatterException {

 		DatabaseDefinition dd = getConfiguration().getDatabase(options.getDatabaseName());

 		FormatterDefinition fd = configuration.getFormatter(options.getFormatterName());

 		try (DatabaseConnection c = dd.connect(options.getDatabaseProperties())) {

 			log.log(Level.FINE, "Database connected");

 			try (Formatter f = fd.getInstance(new FormatterContext(options.getOutputStream(), options.getFormatterProperties()))) {

 				c.executeQuery(options.getSQLCommand(), f);

 			}

 		}

 	}

 	private void processPrepareBatch() throws BatchException {

 		BatchEncoder enc = new BatchEncoder();

 		int length = enc.encode(options.getSQLCommand(), options.getOutputStream());

 		log.log(Level.FINE, "Prepared batch size: {0} bytes", length);

 	}

 	private void processExecuteBatch() throws ConfigurationException, SQLException, FormatterException, BatchException {

 		BatchDecoder dec = new BatchDecoder();

 		Batch b = dec.decode(options.getInputStream());

 		DatabaseDefinition dd = getConfiguration().getDatabase(options.getDatabaseName());

 		FormatterDefinition fd = configuration.getFormatter(options.getFormatterName());

 		try (DatabaseConnection c = dd.connect(options.getDatabaseProperties())) {

 			log.log(Level.FINE, "Database connected");

 			try (Formatter f = fd.getInstance(new FormatterContext(options.getOutputStream(), options.getFormatterProperties()))) {

 				c.executeBatch(b, f);

 			}

 		}

 	}

 	@Override

 	public Configuration getConfiguration() throws ConfigurationException {

 		if (configuration == null) {

 			configuration = loadConfiguration();

 		}

 		return configuration;

 	}

 	private void installDefaultConfiguration() throws ConfigurationException {

 		Constants.DIR.mkdir();

 		if (Constants.CONFIG_FILE.exists()) {

 			log.log(Level.FINER, "Config file already exists: {0}", Constants.CONFIG_FILE);

 		} else {

 			try {

 				Functions.installResource(Constants.EXAMPLE_CONFIG_FILE, Constants.CONFIG_FILE);

 				log.log(Level.FINE, "Installing default config file: {0}", Constants.CONFIG_FILE);

 			} catch (IOException e) {

 				throw new ConfigurationException("Unable to write example configuration to " + Constants.CONFIG_FILE, e);

 			}

 		}

 	}

 	private Configuration loadConfiguration() throws ConfigurationException {

 		try {

 			JAXBContext jaxb = JAXBContext.newInstance(Configuration.class);

 			Unmarshaller u = jaxb.createUnmarshaller();

 			return (Configuration) u.unmarshal(Constants.CONFIG_FILE);

 		} catch (Exception e) {

 			throw new ConfigurationException("Unable to load configuration from " + Constants.CONFIG_FILE, e);

 		}

 	}

 	private void generateBashCompletion() {

 		if (configuration == null) {

 			log.log(Level.FINER, "Not writing Bash completion helper files. In order to generate these files please run some command which requires configuration.");

 		} else {

 			try {

 				File dir = new File(Constants.DIR, "bash-completion");

 				dir.mkdir();

 				writeBashCompletionHelperFile(configuration.getDatabases(), new File(dir, "databases"));

 				writeBashCompletionHelperFile(configuration.getAllFormatters(), new File(dir, "formatters"));

 			} catch (Exception e) {

 				log.log(Level.WARNING, "Unable to generate Bash completion helper files", e);

 			}

 		}

 	}

 	private void writeBashCompletionHelperFile(Collection<? extends NameIdentified> items, File target) throws FileNotFoundException {

 		if (Constants.CONFIG_FILE.lastModified() > target.lastModified()) {

 			try (PrintWriter fw = new PrintWriter(target)) {

 				for (NameIdentified dd : items) {

 					fw.println(dd.getName());

 				}

 				fw.close();

 				log.log(Level.FINE, "Bash completion helper file was written: {0}", target);

 			}

 		} else {

 			log.log(Level.FINER, "Not writing Bash completion helper file: {0} because configuration {1} has not been changed", new Object[]{target, Constants.CONFIG_FILE});

 		}

 	}

 }