package net.sourceforge.fenixedu.util.kerberos;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

import net.sourceforge.fenixedu._development.Custodian;
import net.sourceforge.fenixedu._development.LogLevel;
import net.sourceforge.fenixedu._development.PropertiesManager;
import net.sourceforge.fenixedu.persistenceTier.ExcepcaoPersistencia;

import org.joda.time.DateTime;

import pt.utl.ist.fenix.tools.util.StringAppender;

public class Script {

    private static String createCommand(final String scriptName, final String user) {
	final String script = PropertiesManager.getProperty(scriptName);
	return StringAppender.append(script, " ", user);
    }

    public static void runCommand(final String commandString, final String user, final String pass) throws KerberosException,
	    ExcepcaoPersistencia {
	long time1 = System.currentTimeMillis();
	final String command = createCommand(commandString, user);
	long time2 = System.currentTimeMillis();
	ScriptResult scriptResult = runCmd(command, pass);
	long time3 = System.currentTimeMillis();
	outputRunCommandTime(commandString, time1, time2, time3);

	if (scriptResult.getExitCode() == -1) {
	    throw new ExcepcaoPersistencia(scriptResult.getReturnCode());
	} else {
	    if (scriptResult.getExitCode() == 1) {
		throw new KerberosException(scriptResult.getExitCode(), scriptResult.getReturnCode());
	    }
	}
    }

    private static void outputRunCommandTime(final String commandString, final long time1, final long time2, final long time3) {
	if (LogLevel.INFO) {
	    System.out.print("Command ");
	    System.out.print(commandString);
	    System.out.print(" took ");
	    System.out.print(time2 - time1);
	    System.out.print(" + ");
	    System.out.print(time3 - time2);
	    System.out.print(" = ");
	    System.out.print(time3 - time1);
	    System.out.print(" (ms)");
	}
    }

    public static DateTime returnExpirationDate(String user) throws KerberosException, ExcepcaoPersistencia {
	final String command = createCommand("passExpirationScript", user);
	final ScriptResult scriptResult = runCmd(command, "");

	if (scriptResult.getExitCode() == -1) {
	    throw new ExcepcaoPersistencia(scriptResult.getReturnCode());
	} else {
	    if (scriptResult.getExitCode() == 1) {
		throw new KerberosException(scriptResult.getExitCode(), scriptResult.getReturnCode());
	    }
	}

	String dateString = scriptResult.getReturnCode();
	return new DateTime(Long.valueOf(dateString) * (long) 1000);
    }

    public static void changeKerberosPass(String user, String pass) throws KerberosException, ExcepcaoPersistencia {
	System.out.println("Calling change password script.");
	runCommand("changePassScript", user, pass);
    }

    public static void createUser(String user, String pass) throws KerberosException, ExcepcaoPersistencia {
	System.out.println("Calling create user script.");
	runCommand("createUserScript", user, pass);
    }

    public static void verifyPass(String user, String pass) throws KerberosException, ExcepcaoPersistencia {
	System.out.println("Calling verify password script.");
	runCommand("verifyPassScript", user, pass);
    }

    private static ScriptResult runCmd(String cmd, String pass) {
	Process process = null;
	BufferedWriter outCommand = null;
	BufferedReader bufferedReader = null;
	ScriptWatchDog watchDog = new ScriptWatchDog(Float.valueOf(PropertiesManager.getProperty("scriptTimeout")).longValue());

	try {
	    process = Runtime.getRuntime().exec(cmd);
	    outCommand = new BufferedWriter(new OutputStreamWriter(process.getOutputStream()));
	    bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream()));
	    outCommand.write(pass);
	    outCommand.newLine();
	    outCommand.flush();

	    watchDog.start(process);
	    int exitCode = process.waitFor();
	    watchDog.stop();
	    String returnCode;
	    if (watchDog.killedProcess()) {
		exitCode = -1;
		returnCode = "Timeout";
	    } else {
		returnCode = bufferedReader.readLine();
		if (exitCode != 1 && exitCode != 0) {
		    exitCode = -1;
		}
	    }
	    return new ScriptResult(exitCode, returnCode);

	} catch (IOException ex) {
	    System.out.println(Runtime.getRuntime().freeMemory());
	    System.out.println(Runtime.getRuntime().totalMemory());
	    ex.printStackTrace();
	    try {
		Custodian.dumpThreadTrace();
	    } catch (Exception e) {
		// do nothing. no log will be produced.
	    }
	    return new ScriptResult(-1, ex.getMessage());
	} catch (Exception ex) {
	    ex.printStackTrace();
	    return new ScriptResult(-1, ex.getMessage());
	} finally {
	    try {
		if (outCommand != null)
		    outCommand.close();
		if (bufferedReader != null)
		    bufferedReader.close();
		if (process != null)
		    process.destroy();
		watchDog.stop();
	    } catch (Exception e) {

	    }
	}
    }

    private static class ScriptResult {
	private int exitCode;

	private String returnCode;

	public ScriptResult(int exitCode, String returnCode) {
	    this.exitCode = exitCode;
	    this.returnCode = returnCode;
	}

	public int getExitCode() {
	    return exitCode;
	}

	public void setExitCode(int exitCode) {
	    this.exitCode = exitCode;
	}

	public String getReturnCode() {
	    return returnCode;
	}

	public void setReturnCode(String returnCode) {
	    this.returnCode = returnCode;
	}
    }
}