/*
 * $Id$
 *
 * Copyright (C) 2003-2015 JNode.org
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library 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 Lesser General Public 
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; If not, write to the Free Software Foundation, Inc., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
package org.jnode.shell.bjorne;

import org.jnode.driver.console.CompletionInfo;
import org.jnode.shell.CommandLine;
import org.jnode.shell.CommandShell;
import org.jnode.shell.CommandThread;
import org.jnode.shell.ShellException;
import org.jnode.shell.ShellFailureException;
import org.jnode.shell.ShellInvocationException;
import org.jnode.shell.help.CompletionException;
import org.jnode.shell.io.CommandIO;
import org.jnode.shell.io.CommandIOHolder;
import org.jnode.vm.VmExit;

public class SimpleCommandNode extends CommandNode implements BjorneCompletable {

    private BjorneToken[] assignments;

    private final BjorneToken[] words;
    

    public SimpleCommandNode(int nodeType, BjorneToken[] words) {
        super(nodeType);
        this.words = words;
    }

    public void setAssignments(BjorneToken[] assignments) {
        this.assignments = assignments;
    }

    public BjorneToken[] getWords() {
        return words;
    }

    public BjorneToken[] getAssignments() {
        return assignments;
    }

    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("SimpleCommand{").append(super.toString());
        if (assignments != null) {
            sb.append(",assignments=");
            appendArray(sb, assignments);
        }
        if (words != null) {
            sb.append(",words=");
            appendArray(sb, words);
        }
        sb.append('}');
        return sb.toString();
    }

    @Override
    public int execute(final BjorneContext context) throws ShellException {
        CommandIOHolder[] holders = null;
        int rc;
        try {
            BjorneToken[] words = getWords();
            if (words.length == 0) {
                // No command to run: assignments are done in the shell's context
                context.performAssignments(assignments);
                // Surprisingly, we still need to perform the redirections
                BjorneContext childContext = new BjorneContext(context);
                childContext.evaluateRedirections(getRedirects());
                rc = 0;
            } else {
                // FIXME ... strictly speaking, alias substitution should be performed
                // before "applying the grammatical rules" (i.e. parsing).
                words = context.substituteAliases(words);
                CommandLine command = context.buildCommandLine(words);
                // Assignments and redirections are done in the command's context
                BjorneContext childContext = new BjorneContext(context);
                childContext.performAssignments(assignments);
                holders = childContext.evaluateRedirections(getRedirects());
                CommandIO[] ios = new CommandIO[holders.length];
                for (int i = 0; i < ios.length; i++) {
                    ios[i] = holders[i].getIO();
                }
                if ((getFlags() & BjorneInterpreter.FLAG_ASYNC) != 0) {
                    throw new ShellFailureException(
                            "asynchronous execution (&) not implemented yet");
                } else {
                    rc = childContext.execute(command, ios);
                }
            }
        } catch (BjorneControlException ex) {
            if (ex.getControl() == BjorneInterpreter.BRANCH_EXIT) {
                throw new VmExit(ex.getCount());
            } else {
                throw ex;
            }
        } catch (ShellInvocationException ex) {
            context.getShell().resolvePrintStream(context.getIO(2)).println(ex.getMessage());
            rc = 1;
        } finally {
            if (holders != null) {
                for (CommandIOHolder holder : holders) {
                    holder.close();
                }
            }
        }
        if ((getFlags() & BjorneInterpreter.FLAG_BANG) != 0) {
            rc = (rc == 0) ? -1 : 0;
        }
        context.setLastReturnCode(rc);
        return rc;
    }
    
    public CommandThread fork(CommandShell shell, BjorneContext context) 
        throws ShellException {
        if (words.length > 0) {
            CommandLine command = context.buildCommandLine(words);
            command.setStreams(context.getIOs());
            return shell.invokeAsynchronous(command);
        } else {
            return null;
        }
    }

    @Override
    public void complete(CompletionInfo completions, BjorneContext context, CommandShell shell,
            boolean argumentAnticipated)
        throws CompletionException {
        try {
            CommandLine command = context.buildCommandLine(words);
            String commandName = command.getCommandName();
            if (commandName != null && BjorneInterpreter.isBuiltin(commandName)) {
                BjorneBuiltinCommandInfo commandInfo = 
                    BjorneInterpreter.BUILTINS.get(commandName).buildCommandInfo(context);
                command.setCommandInfo(commandInfo);
            } 
            command.setArgumentAnticipated(argumentAnticipated);
            command.complete(completions, shell);
        } catch (ShellException ex) {
            throw new CompletionException("Shell exception", ex);
        }
    }
}