source: trunk/modelicaml/org.openmodelica.modelicaml.simulation/src/org/modelica/OMCProxy.java @ 947

/*
 * This file is part of OpenModelica.
 *
 * Copyright (c) 1998-CurrentYear, Open Source Modelica Consortium (OSMC),
 * c/o Linköpings universitet, Department of Computer and Information Science,
 * SE-58183 Linköping, Sweden.
 *
 * All rights reserved.
 *
 * THIS PROGRAM IS PROVIDED UNDER THE TERMS OF GPL VERSION 3 LICENSE OR 
 * THIS OSMC PUBLIC LICENSE (OSMC-PL). 
 * ANY USE, REPRODUCTION OR DISTRIBUTION OF THIS PROGRAM CONSTITUTES RECIPIENT'S ACCEPTANCE
 * OF THE OSMC PUBLIC LICENSE OR THE GPL VERSION 3, ACCORDING TO RECIPIENTS CHOICE. 
 *
 * The OpenModelica software and the Open Source Modelica
 * Consortium (OSMC) Public License (OSMC-PL) are obtained
 * from OSMC, either from the above address,
 * from the URLs: http://www.ida.liu.se/projects/OpenModelica or  
 * http://www.openmodelica.org, and in the OpenModelica distribution. 
 * GNU version 3 is obtained from: http://www.gnu.org/copyleft/gpl.html.
 *
 * This program is distributed WITHOUT ANY WARRANTY; without
 * even the implied warranty of  MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE, EXCEPT AS EXPRESSLY SET FORTH
 * IN THE BY RECIPIENT SELECTED SUBSIDIARY LICENSE CONDITIONS OF OSMC-PL.
 *
 * See the full OSMC Public License conditions for more details.
 *
 * Main author: Wladimir Schamai, EADS Innovation Works / Linköping University, 2009-now
 *
 * Contributors: 
 *   Uwe Pohlmann, University of Paderborn 2009-2010, contribution to the Modelica code generation for state machine behavior, contribution to Papyrus GUI adoptations
 *   Parham Vasaiely, EADS Innovation Works / Hamburg University of Applied Sciences 2009-2011, implementation of simulation plugins
 */

package org.modelica;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.StringTokenizer;

import org.omg.CORBA.ORB;

// TODO: Auto-generated Javadoc
/**
 * The OMCProxy is the glue between the OpenModelica Compiler and MDT.
 * It uses the interactive API of OMC to get information about classes
 * and to load classes into OMC.
 * 
 * @author Andreas Remar
 * @author Adrian Pop
 */
public class OMCProxy 
{
    
    /* the CORBA object */
    /** The omcc. */
    private static OmcCommunication omcc;
    
    /** The corba session name. */
    private static String corbaSessionName = "ECLIPSE";
        
    /**
     * The Enum osType.
     */
    enum osType { /** The WINDOWS. */
 WINDOWS, /** The UNIX. */
 UNIX };
    
    /* what Operating System we're running on */
    /** The os. */
    private static osType os;
    
    /* indicates if we've setup the communication with OMC */
    /** The has initialized. */
    private static boolean hasInitialized = false;
    
    /* indicates if the Modelica System Library has been loaded */
    /** The system library loaded. */
    private boolean systemLibraryLoaded = false;

    /** The standard library packages. */
    private String[] standardLibraryPackages = { "Modelica" };

    /* debug options  */
    /* should we trace the calls to sendExpression? */
    /** The trace omc calls. */
    private static boolean traceOMCCalls = true;
    
    /** The trace omc status. */
    private static boolean traceOMCStatus = true;

    /** The existing corba file is new. */
    private static boolean existingCorbaFileIsNew = false;
    
    /**
     * Instantiates a new oMC proxy.
     */
    public OMCProxy()
    {
        
    }

    /**
     * Reads in the OMC CORBA object reference from a file on disk.
     * 
     * @return the object reference as a <code>String</code>
     * @throws ConnectException
     *             the connect exception
     */
    private static String readObjectFromFile() throws ConnectException
    {
        File f = new File(getPathToObject());
        String stringifiedObjectReference = null;

        BufferedReader br = null;
        FileReader fr = null;
        try
        {
            fr = new FileReader(f);
        }
        catch(IOException e)
        {
            throw new ConnectException("Unable to read OpenModelica Compiler CORBA object from " + f.toString());
        }

        br = new BufferedReader(fr);
            
        try
        {
            stringifiedObjectReference = br.readLine();
        }
        catch(IOException e)
        {
            throw new ConnectException("Unable to read OpenModelica Compiler"
                    + " CORBA object from " + getPathToObject());
        }
        return stringifiedObjectReference;
    }
    
    /**
     * Checks if is checks for initialized.
     * 
     * @return true, if is checks for initialized
     */
    public static boolean isHasInitialized() {
        return hasInitialized;
    }

    /**
     * Sets the checks for initialized.
     * 
     * @param has
     *            the new checks for initialized
     */
    public static void setHasInitialized(boolean has) {
        hasInitialized = has;
    }
    
    /**
     * Checks if is existing corba file is new.
     * 
     * @return true, if is existing corba file is new
     */
    public static boolean isExistingCorbaFileIsNew() {
        return existingCorbaFileIsNew;
    }

    /**
     * Sets the existing corba file is new.
     * 
     * @param existingCorbaFileIsNew
     *            the new existing corba file is new
     */
    public static void setExistingCorbaFileIsNew(boolean existingCorbaFileIsNew) {
        OMCProxy.existingCorbaFileIsNew = existingCorbaFileIsNew;
    }

    /**
     * Gets the path to object.
     * 
     * @return Returns the path to the OMC CORBA object that is stored on disk.
     */
    private static String getPathToObject()
    {
        String fileName = null;

        /* This mirrors the way OMC creates the object file. */     
        switch (os)
        {
        case UNIX:
            String username = System.getenv("USER");
            if(username == null)
            {
                username = "nobody";
            }
            fileName = "/tmp/openmodelica." + username + ".objid." + corbaSessionName;
            break;
        case WINDOWS:
            String temp = System.getenv("TMP");         
            fileName = temp + "\\openmodelica.objid." + corbaSessionName;
            break;
        default:
            logBug("org.modelica", "os variable set to unexpected os-type");
        }
        
        logOMCStatus("Will look for OMC object reference in '" 
                + fileName + "'.");
        
        return fileName;
    }
    
    /**
     * With the help of voodoo magic determines the path to the
     * omc binary that user (probably) wants to use and the working
     * direcoty of where that binary (most likely) should be started in
     * 
     * This will returns for example 'c:\openmodelica132\omc.exe'
     * or '/usr/local/share/openmodelica/omc' depending on
     * such factors as: OS type, environment variables settings,
     * plugin user preferences, where the first matching
     * binary found and the weather outside. 
     * 
     * @return full path to the omc binary  
     * @throws ConnectException if the path could not be determined
     */
    private static File[] getOmcBinaryPaths() throws ConnectException
    {
        String binaryName = "omc";
        
        if (os == osType.WINDOWS)
        {
            binaryName += ".exe";
        }
        
        File omcBinary = null;
        File omcWorkingDirectory = null;
        /*
         * user specified that standard path to omc should be used,
         * try to determine the omc path via the OPENMODELICAHOME and
         * by checking in it's varius subdirectory for the omc binary file
         */
        logOMCStatus("Using OPENMODELICAHOME environment variable to find omc-binary");
        
        /* 
         * Standard path to omc (or omc.exe) binary is encoded in OPENMODELICAHOME
         * variable. 
         */
        String openModelicaHome = System.getenv("OPENMODELICAHOME");
        if(openModelicaHome == null)
        {
            final String m = "Environment variable OPENMODELICAHOME not set";
            logOMCStatus("Environment variable OPENMODELICAHOME not set,"+
                    " don't know how to start OMC from standard path.");
            throw new ConnectException(m);
        }
        
        omcWorkingDirectory = new File(openModelicaHome);
        
        /* the subdirectories where omc binary may be located, hurray for standards! */
        String[] subdirs = { "", "bin", "Compiler" };
        
        for (String subdir : subdirs)
        {
        
            String path = omcWorkingDirectory.getAbsolutePath() + File.separator;
            path += subdir.equals("") ? binaryName :  subdir + File.separator + binaryName;

            File file = new File(path); 

            if (file.exists())
            {
                omcBinary = file;
                logOMCStatus("Using omc-binary at '" + omcBinary.getAbsolutePath() + "'");
                break;
            }
            else
            {
                logOMCStatus("No omc binary at: [" + path + "]");
            }
        }
        
        if (omcBinary == null)
        {
            logOMCStatus("Could not fine omc-binary on the OPENMODELICAHOME path");
            throw new ConnectException("Unable to start the OpenModelica Compiler, binary not found");
        }

        return new File[] {omcBinary, omcWorkingDirectory};
    }
    
    /**
     * Start a new OMC server.
     * 
     * @throws ConnectException
     *             the connect exception
     */
    private static void startServer() throws ConnectException
    {
        File tmp[] = getOmcBinaryPaths();

        File omcBinary = tmp[0];
        File workingDirectory = new File(".");

        
        /* 
         * Delete old object reference file. We need to do this because we're
         * checking if the file exists to determine if the server has started
         * or not (further down). 
         */
        File f = new File(getPathToObject());
        long lastModified = 0;      
        if(f.exists())
        {
            lastModified = f.lastModified();
            logOMCStatus("OMC object reference file is already on disk, we try to use it.");
            if (existingCorbaFileIsNew) return;
            logOMCStatus("OMC object reference file is already on disk, but is old, start a new server.");
        }
        
        String command[] = { omcBinary.getAbsolutePath(), "+c=" + corbaSessionName, "+d=interactiveCorba" };
        try
        {
            logOMCStatus("Running command " + command[0] + " " + command[1] + " " + command[2]);
            logOMCStatus("Setting working directory to " + workingDirectory.getAbsolutePath());
            ProcessStartThread pt = new ProcessStartThread(command, workingDirectory);
            pt.start();
        }
        catch(Exception e)
        {
            e.printStackTrace();
            logOMCStatus("Error running command " + e.getMessage());
            logOMCStatus("Unable to start OMC, giving up."); 
            throw new ConnectException("Unable to start the OpenModelica Compiler. ");
        }           

        logOMCStatus("Waiting for OMC CORBA object reference to appear on disk.");
        existingCorbaFileIsNew = true;
        
        /*
         * Wait until the object exists on disk, but if it takes longer than
         * 5 seconds, abort. (Very arbitrary 5 seconds..)
         */
        int ticks = 0;
        while(!f.exists() || (f.exists() && lastModified == f.lastModified()) )
        {
            try
            {
                logOMCStatus("Waiting for OMC CORBA object reference to appear on disk ... for "+ (ticks+1) + " seconds");
                Thread.sleep(100);
            }
            catch(InterruptedException e)
            {
                /* ignore */
            }
            ticks++;
            
            /* If we've waited for around 5 seconds, abort the wait for OMC */
            if(ticks > 50)
            {
                logOMCStatus("No OMC object reference file created after approximately 50 seconds.");
                logOMCStatus("It seems OMC does not want to start, giving up.");
                throw new ConnectException("Unable to start the Open Modelica Compiler. Waited for 5 seconds, but it didn't respond.");
            }
        }
        logOMCStatus("The new OMC object reference found.");
    }
    
    /**
     * Initializes an ORB, converts the stringified OMC object to a real CORBA
     * object, and then narrows that object to an OmcCommunication object.
     * 
     * @param stringifiedObjectReference
     *            the new up omcc
     */
    private static void setupOmcc(String stringifiedObjectReference)
    {
        /* Can't remember why this is needed. But it is. */
        String args[] = {null};

        /* set the CORBA read timeout to a larger value as we send huge 
ammounts of data
         * from OMC to MDT
         */
        System.setProperty("com.sun.CORBA.transport.ORBTCPReadTimeouts", "1:60000:300:1");
        
        ORB orb;
        orb = ORB.init(args, null);     

        /* Convert string to object. */
        org.omg.CORBA.Object obj = 
orb.string_to_object(stringifiedObjectReference);       

        /* Convert object to OmcCommunication object. */
        omcc = OmcCommunicationHelper.narrow(obj);

    }
    
    /**
     * Gets the os.
     * 
     * @return the name of the operating system. If an unknown os is found, the
     *         default is Unix.
     */
    private static osType getOs()
    {
        String osName = System.getProperty("os.name");
        if(osName.contains("Linux"))
        {
            return osType.UNIX;
        }
        else if(osName.contains("Windows"))
        {
            return osType.WINDOWS;
        }
        else
        {
            logWarning("'" + osName + "' not officialy supported OS");
            /* If the OS is not GNU/Linux or Windows, default to Unix */
            return osType.UNIX;
        }
    }

    /**
     * Initialize the communication with OMC.
     * 
     * @throws ConnectException
     *             if we're unable to start communicating with the server
     */
    private void init() throws ConnectException
    {
        /* 
         * Get type of operating system, used for finding object
         * reference and starting OMC if the reference is faulty 
         */
        os = getOs();
        
        /* See if an OMC server is already running */
        File f = new File(getPathToObject());
        String stringifiedObjectReference = null;
        if(!f.exists())
        {
            /* If a server isn't running, start it */
            logOMCStatus("No OMC object reference found, starting server.");
            startServer();
        }
        else
        {
            logOMCStatus("Old OMC CORBA object reference present," + " assuming OMC is running.");
        }
        
        /* Read in the CORBA OMC object from a file on disk */
        stringifiedObjectReference = readObjectFromFile();

        /*
         * Setup up OMC object reference by initializing ORB and then
         * converting the string object to a real CORBA object.
         */
        setupOmcc(stringifiedObjectReference);

        try
        {
            /*
             * Test the server by trying to send an expression to it. 
             * This might fail if the object reference found on disk didn't
             * have a corresponding server running. If a server is missing,
             * catch an exception and try starting a server.
             */
            logOMCStatus("Trying to send expression to OMC.");
            omcc.sendExpression("1+1");
            logOMCStatus("Expression sent successfully.");
        }
        catch(org.omg.CORBA.COMM_FAILURE e)
        {
            /* Start server and set up omcc */
            logOMCStatus("Failed sending expression, will try to start OMC.");
            existingCorbaFileIsNew = false;
            startServer();
            stringifiedObjectReference = readObjectFromFile();
            setupOmcc(stringifiedObjectReference);

            try
            {
                /* Once again try to send an expression to OMC. If it fails this
                 * time it's time to send back an exception to the caller of
                 * this function. */
                logOMCStatus("Trying to send expression to OMC.");
                omcc.sendExpression("1+1");
                logOMCStatus("Expression sent successfully.");
            }
            catch(org.omg.CORBA.COMM_FAILURE x)
            {
                logOMCStatus("Failed sending expression, giving up.");
                throw new ConnectException("Unable to start the OpenModelica Compiler.");
            }
        }

        hasInitialized = true;
    }
    
    /**
     * Send expression to OMC. If communication is not initialized, it is
     * initialized here.
     * 
     * @param exp
     *            the expression to send to OMC
     * @return the string
     * @throws ConnectException
     *             if we're unable to start communicating with the server
     */
    // TODO add synchronization so that two threads don't fudge up each others
    // communication with OMC
    // old synchronization aka 'private synchronized String sendExpression(String exp)'
    // doesnt work when there is possibility of multiple instances of OMCProxy objects
    public String sendExpression(String exp)
        throws ConnectException
    {
        String retval = null;
        
        if(hasInitialized == false)
        {
            init();
        }
        
        try
        {
            logOMCCall(exp);
            retval = omcc.sendExpression(exp);
            logOMCReply(retval);
        }
        catch(org.omg.CORBA.COMM_FAILURE x)
        {
            logOMCCallError("Error while sending expression " + exp + " ["+x+"]");
            /* lost connection to OMC or something */
            throw new ConnectException("Couldn't send expression to the "+
                    "OpenModelica Compiler. Tried sending: " + exp);
        }
        
        return retval;
    }
    
    /**
     * Logs the expression sent to OMC if the tracing flag (traceOMCCalls) is
     * set.
     * 
     * @param expression
     *            the expression that is about to be sent to OMC
     */
    public static void logOMCCall(String expression)
    {
        if (!traceOMCCalls)
        {
            return;
        }
        System.out.println(">> " + expression);
    }
    
    /**
     * outputs the message about a call error that occured when communicating
     * with omc.
     * 
     * @param message
     *            the message to log
     */
    public static void logOMCCallError(String message)
    {
        if(!traceOMCCalls)
        {
            return;
        }
        System.out.println(message);
    }
    
    /**
     * loggs the message conserning OMC status if the tracing flag
     * traceOMCStatus is set.
     * 
     * @param message
     *            the message to log
     */
    public static void logOMCStatus(String message)
    {
        if (!traceOMCStatus)
        {
            return;
        }
        System.out.println("OMCSTATUS: " + message);
    }

    /**
     * Logs the reply received from OMC if the tracing flag (traceOMCCalls) is
     * set.
     * 
     * @param reply
     *            the reply recieved from the OMC
     */
    public static void logOMCReply(String reply)
    {
        if (!traceOMCCalls)
        {
            return;
        }

        StringTokenizer tokenizer = new StringTokenizer(reply, "\n");
        
        while (tokenizer.hasMoreTokens())
        {
            System.out.println("<< " + tokenizer.nextToken());
        }
    }
    
    /**
     * Get the classes contained in a class (a package is a class..)
     * 
     * @param className
     *            full class name where to look for packages
     * @return a <code>List</code> of subclasses defined (and loaded into OMC)
     *         inside the class named className.
     * @throws ConnectException
     *             the connect exception
     */ 
    public String getClassNames(String className) throws ConnectException
    {
        String retval = sendExpression("getClassNames("+className+")");
        
        /* fetch error string but ignore it */
        getErrorString();
                
        return retval;
    }

    /**
     * Gets the type of restriction of a class.
     * 
     * @param className
     *            fully qualified class name
     * @return the type of restriction of the class
     * @throws ConnectException
     *             the connect exception
     */
    public String getRestriction(String className) throws ConnectException
    {
        String reply = sendExpression("getClassRestriction(" + className + ")");

        /* remove " around the reply */
        reply = reply.trim();
                
        return reply;
    }
    
    /**
     * Fetches the error string from OMC. This should be called after an "Error"
     * is received. (Or whenever the queue of errors should be emptied.)
     * 
     * @return the <code>String</code> of errors
     * @throws ConnectException
     *             the connect exception
     */
    private String getErrorString() throws ConnectException
    {
        String res = sendExpression("getErrorString()");
        
        /* Make sure the error string isn't empty */
        if(res != null && res.length() > 2)
        {
            res = res.trim();
            return res.substring(1, res.length() - 1);
        }
        else
            return "";
    }
    

    /**
     * Tries to load file into OMC which causes it to be parsed and the syntax
     * checked.
     * 
     * @param file
     *            the file we want to load
     * @return a <code>ParseResult</code> containing the classes found in the
     *         file and the error messages from OMC
     * @throws ConnectException
     *             the connect exception
     */
    public String loadSourceFile(String file) throws ConnectException
    {
        String retval = sendExpression("loadFileInteractiveQualified(\"" + file + "\")");
        retval = retval.trim();
        // String errorString = getErrorString();
        /*
         * See if there were parse errors, an empty list {} also denotes error
         */
        return retval;
    }

    /**
     * Gets the location (file, starting and ending line number and column
     * number) of a Modelica element.
     * 
     * @param className
     *            the element we want to get location of
     * @return an <code>ElementLocation</code> containing the file, starting and
     *         ending line number and column number of the given class
     * @throws ConnectException
     *             the connect exception
     * @throws InvocationError
     *             the invocation error
     */
    public String getClassLocation(String className) throws ConnectException, InvocationError 
    {
        String retval = sendExpression("getCrefInfo(" + className + ")");
        
        /* fetch error string but ignore it */
        getErrorString();
        
        if(retval.contains("Error") || retval.contains("error"))
        {
            throw new 
                InvocationError("Fetching file position of " + className, "getCrefInfo(" + className + ")");
        }
        
        
        /*
         * The getCrefInfo reply has the following format:
         * 
         * <file path>,<something>,<start line>,<start column>,<end line>,<end column>
         * 
         * for example:
         * /foo/Modelica/package.mo,writable,1,1,1029,13
         */

        /* For some reason, the list returned doesn't contain curly braces. */
        retval = retval.trim();
        retval = "{" + retval + "}"; 
                
        return retval;
    }
    
    /**
     * Queries the compiler if a particular modelica class/package is a package.
     * 
     * @param className
     *            fully qualified name of the class/package
     * @return true if className is a package, false otherwise
     * @throws ConnectException
     *             the connect exception
     */
    public boolean isPackage(String className) throws ConnectException 
    {
        String retval = sendExpression("isPackage(" + className + ")");

        /* fetch error string but ignore it */
        getErrorString();
        
        return retval.contains("true");
    }
    
    /**
     * Uses the OMC API call getElementsInfo to fetch lots of information about
     * a class definition. See interactive_api.txt in the OMC source tree.
     * 
     * @param className
     *            the fully qualified name of a class
     * @return a <code>Collection</code> (of <code>ElementsInfo</code>)
     *         containing the information about className
     * @throws ConnectException
     *             the connect exception
     * @throws InvocationError
     *             the invocation error
     */
    public String getElements(String className) throws ConnectException, InvocationError
    {
        String retval = sendExpression("getElementsInfo("+ className +")");
        
        /* fetch error string */
        getErrorString();
        
        return retval;
    }

    /**
     * Gets the class info.
     * 
     * @param className
     *            the class name
     * @return the class info
     * @throws ConnectException
     *             the connect exception
     */
    public String getClassInfo(String className) throws ConnectException
    {
        String retval = sendExpression("getClassInformation("+ className +")");
        
        /* fetch error string but ignore it */
        getErrorString();
                
        return  retval;
    }

    
    /**
     * Gets the compiler name.
     * 
     * @return the name of the compiler that this plugin tries to communicate
     *         with (at least it tries...)
     */
    public String getCompilerName()
    {
        return "OpenModelica Compiler";
    }

    /**
     * Loads in the Modelica System Library and returns names of the top-level
     * packages.
     * 
     * @return the standard library
     * @throws ConnectException
     *             if we're unable to start communicating with the server
     */ 
    public String[] getStandardLibrary() throws ConnectException
    {
        if (!systemLibraryLoaded)
        {
            sendExpression("loadModel(Modelica)");
            
            /* fetch error string but ignore it */
            getErrorString();
            
            systemLibraryLoaded = true;
        }

        return standardLibraryPackages;
    }
    
    /**
     * Log bug.
     * 
     * @param where
     *            the where
     * @param message
     *            the message
     */
    public static void logBug(String where, String message)
    {
        System.out.println("Error: " + where + " Message: "+ message);
    }

    /**
     * Log warning.
     * 
     * @param message
     *            the message
     */
    public static void logWarning(String message)
    {
        System.out.println("Warning: " + message);
    }

}