/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you 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 .
 */

#include <config_folders.h>

#include <osl/diagnose.h>
#include <osl/thread.h>
#include <osl/process.h>
#include <osl/file.hxx>
#include <rtl/ustrbuf.hxx>

#include <rtl/uri.hxx>
#include "shellexec.hxx"
#include <com/sun/star/system/SystemShellExecuteFlags.hpp>

#include <com/sun/star/util/theMacroExpander.hpp>
#include <com/sun/star/uri/XExternalUriReferenceTranslator.hpp>
#include <com/sun/star/uri/ExternalUriReferenceTranslator.hpp>
#include <com/sun/star/uri/UriReferenceFactory.hpp>
#include <cppuhelper/supportsservice.hxx>

#include "uno/current_context.hxx"

#include <cstdlib>
#include <string.h>
#include <errno.h>
#include <unistd.h>

using com::sun::star::system::XSystemShellExecute;
using com::sun::star::system::SystemShellExecuteException;

using namespace ::com::sun::star::uno;
using namespace ::com::sun::star::lang;
using namespace ::com::sun::star::system::SystemShellExecuteFlags;
using namespace cppu;

namespace
{
    Sequence< OUString > SAL_CALL ShellExec_getSupportedServiceNames()
    {
        Sequence< OUString > aRet { "com.sun.star.system.SystemShellExecute" };
        return aRet;
    }
}

void escapeForShell( OStringBuffer & rBuffer, const OString & rURL)
{
    sal_Int32 nmax = rURL.getLength();
    for(sal_Int32 n=0; n < nmax; ++n)
    {
        // escape every non alpha numeric characters (excluding a few "known good") by prepending a '\'
        sal_Char c = rURL[n];
        if( ( c < 'A' || c > 'Z' ) && ( c < 'a' || c > 'z' ) && ( c < '0' || c > '9' )  && c != '/' && c != '.' )
            rBuffer.append( '\\' );

        rBuffer.append( c );
    }
}

ShellExec::ShellExec( const Reference< XComponentContext >& xContext ) :
    WeakImplHelper< XSystemShellExecute, XServiceInfo >(),
    m_xContext(xContext)
{
    try {
        Reference< XCurrentContext > xCurrentContext(getCurrentContext());

        if (xCurrentContext.is())
        {
            Any aValue = xCurrentContext->getValueByName( "system.desktop-environment" );

            OUString aDesktopEnvironment;
            if (aValue >>= aDesktopEnvironment)
            {
                m_aDesktopEnvironment = OUStringToOString(aDesktopEnvironment, RTL_TEXTENCODING_ASCII_US);
            }
        }
    } catch (const RuntimeException &) {
    }
}

void SAL_CALL ShellExec::execute( const OUString& aCommand, const OUString& aParameter, sal_Int32 nFlags )
    throw (IllegalArgumentException, SystemShellExecuteException, RuntimeException, std::exception)
{
    OStringBuffer aBuffer, aLaunchBuffer;

    // DESKTOP_LAUNCH, see http://freedesktop.org/pipermail/xdg/2004-August/004489.html
    static const char *pDesktopLaunch = getenv( "DESKTOP_LAUNCH" );

    // Check whether aCommand contains an absolute URI reference:
    css::uno::Reference< css::uri::XUriReference > uri(
        css::uri::UriReferenceFactory::create(m_xContext)->parse(aCommand));
    if (uri.is() && uri->isAbsolute())
    {
        // It seems to be a url ..
        // We need to re-encode file urls because osl_getFileURLFromSystemPath converts
        // to UTF-8 before encoding non ascii characters, which is not what other apps
        // expect.
        OUString aURL = css::uri::ExternalUriReferenceTranslator::create(
                            m_xContext)->translateToExternal(aCommand);
        if ( aURL.isEmpty() && !aCommand.isEmpty() )
        {
            throw RuntimeException(
                "Cannot translate URI reference to external format: "
                 + aCommand,
                static_cast< cppu::OWeakObject * >(this));
        }

#ifdef MACOSX
        //TODO: Using open(1) with an argument that syntactically is an absolute
        // URI reference does not necessarily give expected results:
        // 1  If the given URI reference matches a supported scheme (e.g.,
        //  "mailto:foo"):
        // 1.1  If it matches an existing pathname (relative to CWD):  Results
        //  in "mailto:foo?\n[0]\tcancel\n[1]\tOpen the file\tmailto:foo\n[2]\t
        //  Open the URL\tmailto:foo\n\nWhich did you mean? Cancelled." on
        //  stderr and SystemShellExecuteException.
        // 1.2  If it does not match an exitsting pathname (relative to CWD):
        //  Results in the corresponding application being opened with the given
        //  document (e.g., Mail with a New Message).
        // 2  If the given URI reference does not match a supported scheme
        //  (e.g., "foo:bar"):
        // 2.1  If it matches an existing pathname (relative to CWD) pointing to
        //  an executable:  Results in execution of that executable.
        // 2.2  If it matches an existing pathname (relative to CWD) pointing to
        //  a non-executable regular file:  Results in opening it in TextEdit.
        // 2.3  If it matches an existing pathname (relative to CWD) pointing to
        //  a directory:  Results in opening it in Finder.
        // 2.4  If it does not match an exitsting pathname (relative to CWD):
        //  Results in "The file /.../foo:bar does not exits." (where "/..." is
        //  the CWD) on stderr and SystemShellExecuteException.
        aBuffer.append("open --");
#else
        // Just use xdg-open on non-Mac
        if (std::getenv("LIBO_FLATPAK") != nullptr) {
            aBuffer.append("/app/bin/xdg-open");
        } else {
            aBuffer.append("/usr/bin/xdg-open");
        }
#endif
        aBuffer.append(" ");
        escapeForShell(aBuffer, OUStringToOString(aURL, osl_getThreadTextEncoding()));

        if ( pDesktopLaunch && *pDesktopLaunch )
        {
            aLaunchBuffer.append( OString(pDesktopLaunch) + " ");
            escapeForShell(aLaunchBuffer, OUStringToOString(aURL, osl_getThreadTextEncoding()));
        }
    } else if ((nFlags & css::system::SystemShellExecuteFlags::URIS_ONLY) != 0)
    {
        throw css::lang::IllegalArgumentException(
            "XSystemShellExecute.execute URIS_ONLY with non-absolute"
                     " URI reference "
             + aCommand,
            static_cast< cppu::OWeakObject * >(this), 0);
    } else {
        escapeForShell(aBuffer, OUStringToOString(aCommand, osl_getThreadTextEncoding()));
        aBuffer.append(" ");
        if( nFlags != 42 )
            escapeForShell(aBuffer, OUStringToOString(aParameter, osl_getThreadTextEncoding()));
        else
            aBuffer.append(OUStringToOString(aParameter, osl_getThreadTextEncoding()));
    }

    // Prefer DESKTOP_LAUNCH when available
    if ( !aLaunchBuffer.isEmpty() )
    {
        FILE *pLaunch = popen( aLaunchBuffer.makeStringAndClear().getStr(), "w" );
        if ( pLaunch != nullptr )
        {
            if ( 0 == pclose( pLaunch ) )
                return;
        }
        // Failed, do not try DESKTOP_LAUNCH any more
        pDesktopLaunch = nullptr;
    }

    OString cmd =
#ifdef LINUX
        // avoid blocking (call it in background)
        "( " + aBuffer.makeStringAndClear() +  " ) &";
#else
        aBuffer.makeStringAndClear();
#endif
    FILE *pLaunch = popen(cmd.getStr(), "w");
    if ( pLaunch != nullptr )
    {
        if ( 0 == pclose( pLaunch ) )
            return;
    }

    int nerr = errno;
    throw SystemShellExecuteException(OUString::createFromAscii( strerror( nerr ) ),
        static_cast < XSystemShellExecute * > (this), nerr );
}

// XServiceInfo

OUString SAL_CALL ShellExec::getImplementationName(  )
    throw( RuntimeException, std::exception )
{
    return OUString("com.sun.star.comp.system.SystemShellExecute");
}

sal_Bool SAL_CALL ShellExec::supportsService( const OUString& ServiceName )
    throw( RuntimeException, std::exception )
{
    return cppu::supportsService(this, ServiceName);
}

Sequence< OUString > SAL_CALL ShellExec::getSupportedServiceNames(   )
    throw( RuntimeException, std::exception )
{
    return ShellExec_getSupportedServiceNames();
}

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
