# -*- coding: utf-8 -*-
#
# Copyright © 2009-2010 Pierre Raybaut
# Licensed under the terms of the MIT License
# (see spyderlib/__init__.py for details)

"""External Console plugin"""

# pylint: disable=C0103
# pylint: disable=R0903
# pylint: disable=R0911
# pylint: disable=R0201

# Qt imports
from spyderlib.qt.QtGui import (QVBoxLayout, QMessageBox, QInputDialog,
                                QLineEdit, QPushButton, QGroupBox, QLabel,
                                QTabWidget, QFontComboBox, QHBoxLayout)
from spyderlib.qt.QtCore import SIGNAL, Qt
from spyderlib.qt.compat import getopenfilename

# Stdlib imports
import atexit
import os
import os.path as osp
import re
import sys

# Local imports
from spyderlib.baseconfig import _, SCIENTIFIC_STARTUP, SUPPORTED_IPYTHON
from spyderlib.config import CONF
from spyderlib.utils import programs
from spyderlib.utils.misc import (get_error_match, get_python_executable,
                                  remove_trailing_single_backslash,
                                  is_python_script)
from spyderlib.utils.qthelpers import get_icon, create_action, mimedata2url
from spyderlib.widgets.tabs import Tabs
from spyderlib.widgets.externalshell.pythonshell import ExternalPythonShell
from spyderlib.widgets.externalshell.systemshell import ExternalSystemShell
from spyderlib.widgets.findreplace import FindReplace
from spyderlib.plugins import SpyderPluginWidget, PluginConfigPage


def is_mpl_patch_available():
    """Return True if Matplotlib patch is available"""
    if programs.is_module_installed('matplotlib'):
        from spyderlib import mpl_patch
        return mpl_patch.is_available()
    else:
        return False


def scientific_libs_available(interpreter):
    """
    Return True if numpy, scipy and matplotlib are installed in interpreter
    """
    mods = ['numpy', 'scipy', 'matplotlib']
    check_mods = [programs.is_module_installed(m, interpreter=interpreter) \
                  for m in mods]
    return all(check_mods)


class ExternalConsoleConfigPage(PluginConfigPage):
    def __init__(self, plugin, parent):
        PluginConfigPage.__init__(self, plugin, parent)
        self.get_name = lambda: _("Console")

    def setup_page(self):
        interface_group = QGroupBox(_("Interface"))
        font_group = self.create_fontgroup(option=None, text=None,
                                    fontfilters=QFontComboBox.MonospacedFonts)
        newcb = self.create_checkbox
        singletab_box = newcb(_("One tab per script"), 'single_tab')
        showtime_box = newcb(_("Show elapsed time"), 'show_elapsed_time')
        icontext_box = newcb(_("Show icons and text"), 'show_icontext')

        # Interface Group
        interface_layout = QVBoxLayout()
        interface_layout.addWidget(singletab_box)
        interface_layout.addWidget(showtime_box)
        interface_layout.addWidget(icontext_box)
        interface_group.setLayout(interface_layout)
        
        # Source Code Group
        display_group = QGroupBox(_("Source code"))
        buffer_spin = self.create_spinbox(
                            _("Buffer: "), _(" lines"),
                            'max_line_count', min_=0, max_=1000000, step=100,
                            tip=_("Set maximum line count"))
        wrap_mode_box = newcb(_("Wrap lines"), 'wrap')
        merge_channels_box = newcb(
               _("Merge process standard output/error channels"),
               'merge_output_channels',
               tip=_("Merging the output channels of the process means that\n"
                     "the standard error won't be written in red anymore,\n"
                     "but this has the effect of speeding up display."))
        colorize_sys_stderr_box = newcb(
               _("Colorize standard error channel using ANSI escape codes"),
               'colorize_sys_stderr',
               tip=_("This method is the only way to have colorized standard\n"
                     "error channel when the output channels have been "
                     "merged."))
        self.connect(merge_channels_box, SIGNAL("toggled(bool)"),
                     colorize_sys_stderr_box.setEnabled)
        self.connect(merge_channels_box, SIGNAL("toggled(bool)"),
                     colorize_sys_stderr_box.setChecked)
        colorize_sys_stderr_box.setEnabled(
                                    self.get_option('merge_output_channels'))
        
        display_layout = QVBoxLayout()
        display_layout.addWidget(buffer_spin)
        display_layout.addWidget(wrap_mode_box)
        display_layout.addWidget(merge_channels_box)
        display_layout.addWidget(colorize_sys_stderr_box)
        display_group.setLayout(display_layout)
        
        # Background Color Group
        bg_group = QGroupBox(_("Background color"))
        bg_label = QLabel(_("This option will be applied the next time "
                            "a Python console or a terminal is opened."))
        bg_label.setWordWrap(True)
        lightbg_box = newcb(_("Light background (white color)"),
                            'light_background')
        bg_layout = QVBoxLayout()
        bg_layout.addWidget(bg_label)
        bg_layout.addWidget(lightbg_box)
        bg_group.setLayout(bg_layout)

        # Advanced settings
        source_group = QGroupBox(_("Source code"))
        completion_box = newcb(_("Automatic code completion"),
                               'codecompletion/auto')
        case_comp_box = newcb(_("Case sensitive code completion"),
                              'codecompletion/case_sensitive')
        show_single_box = newcb(_("Show single completion"),
                               'codecompletion/show_single')
        comp_enter_box = newcb(_("Enter key selects completion"),
                               'codecompletion/enter_key')
        calltips_box = newcb(_("Balloon tips"), 'calltips')
        inspector_box = newcb(
                  _("Automatic notification to object inspector"),
                  'object_inspector', default=True,
                  tip=_("If this option is enabled, object inspector\n"
                        "will automatically show informations on functions\n"
                        "entered in console (this is triggered when entering\n"
                        "a left parenthesis after a valid function name)"))
        
        source_layout = QVBoxLayout()
        source_layout.addWidget(completion_box)
        source_layout.addWidget(case_comp_box)
        source_layout.addWidget(show_single_box)
        source_layout.addWidget(comp_enter_box)
        source_layout.addWidget(calltips_box)
        source_layout.addWidget(inspector_box)
        source_group.setLayout(source_layout)

        # UMD Group
        umd_group = QGroupBox(_("User Module Deleter (UMD)"))
        umd_label = QLabel(_("UMD forces Python to reload modules which were "
                             "imported when executing a \nscript in the "
                             "external console with the 'runfile' function."))
        umd_enabled_box = newcb(_("Enable UMD"), 'umd/enabled',
                                msg_if_enabled=True, msg_warning=_(
                        "This option will enable the User Module Deleter (UMD) "
                        "in Python interpreters. UMD forces Python to "
                        "reload deeply modules during import when running a "
                        "Python script using the Spyder's builtin function "
                        "<b>runfile</b>."
                        "<br><br><b>1.</b> UMD may require to restart the "
                        "Python interpreter in which it will be called "
                        "(otherwise only newly imported modules will be "
                        "reloaded when executing scripts)."
                        "<br><br><b>2.</b> If errors occur when re-running a "
                        "PyQt-based program, please check that the Qt objects "
                        "are properly destroyed (e.g. you may have to use the "
                        "attribute <b>Qt.WA_DeleteOnClose</b> on your main "
                        "window, using the <b>setAttribute</b> method)"),
                                )
        umd_verbose_box = newcb(_("Show reloaded modules list"),
                                'umd/verbose', msg_info=_(
                                "Please note that these changes will "
                                "be applied only to new Python interpreters"))
        umd_namelist_btn = QPushButton(
                            _("Set UMD excluded (not reloaded) modules"))
        self.connect(umd_namelist_btn, SIGNAL('clicked()'),
                     self.plugin.set_umd_namelist)
        
        umd_layout = QVBoxLayout()
        umd_layout.addWidget(umd_label)
        umd_layout.addWidget(umd_enabled_box)
        umd_layout.addWidget(umd_verbose_box)
        umd_layout.addWidget(umd_namelist_btn)
        umd_group.setLayout(umd_layout)
        
        # Python executable Group
        pyexec_group = QGroupBox(_("Python executable"))
        pyexec_label = QLabel(_("Path to Python interpreter "
                                "executable binary:"))
        if os.name == 'nt':
            filters = _("Executables")+" (*.exe)"
        else:
            filters = None
        pyexec_file = self.create_browsefile('', 'pythonexecutable',
                                             filters=filters)
        for le in self.lineedits:
            if self.lineedits[le][0] == 'pythonexecutable':
                pyexec_edit = le
        self.connect(pyexec_edit, SIGNAL("textChanged(QString)"),
                     lambda pyexec: self.change_pystartup(pyexec,
                                                          default_radio,
                                                          custom_radio))
        self.connect(pyexec_edit, SIGNAL("textChanged(QString)"),
                     lambda pyexec: self.change_qtapi(pyexec))
        
        pyexec_layout = QVBoxLayout()
        pyexec_layout.addWidget(pyexec_label)
        pyexec_layout.addWidget(pyexec_file)
        pyexec_group.setLayout(pyexec_layout)
        
        # Startup Group
        startup_group = QGroupBox(_("Startup"))
        pystartup_box = newcb(_("Open a Python interpreter at startup"),
                              'open_python_at_startup')
        
        startup_layout = QVBoxLayout()
        startup_layout.addWidget(pystartup_box)
        startup_group.setLayout(startup_layout)
        
        # PYTHONSTARTUP replacement
        pystartup_group = QGroupBox(_("PYTHONSTARTUP replacement"))
        pystartup_label = QLabel(_("This option will override the "
                                   "PYTHONSTARTUP environment variable which\n"
                                   "defines the script to be executed during "
                                   "the Python interpreter startup."))
        default_radio = self.create_radiobutton(
                                        _("Default PYTHONSTARTUP script"),
                                        'pythonstartup/default', True)
        custom_radio = self.create_radiobutton(
                                        _("Use the following startup script:"),
                                        'pythonstartup/custom', False)
        pystartup_file = self.create_browsefile('', 'pythonstartup', '',
                                                filters=_("Python scripts")+\
                                                " (*.py)")
        self.connect(default_radio, SIGNAL("toggled(bool)"),
                     pystartup_file.setDisabled)
        self.connect(custom_radio, SIGNAL("toggled(bool)"),
                     pystartup_file.setEnabled)
        
        pystartup_layout = QVBoxLayout()
        pystartup_layout.addWidget(pystartup_label)
        pystartup_layout.addWidget(default_radio)
        pystartup_layout.addWidget(custom_radio)
        pystartup_layout.addWidget(pystartup_file)
        pystartup_group.setLayout(pystartup_layout)
        
        # Monitor Group
        monitor_group = QGroupBox(_("Monitor"))
        monitor_label = QLabel(_("The monitor provides introspection "
                                 "features to console: code completion, "
                                 "calltips and variable explorer. "
                                 "Because it relies on several modules, "
                                 "disabling the monitor may be useful "
                                 "to accelerate console startup."))
        monitor_label.setWordWrap(True)
        monitor_box = newcb(_("Enable monitor"), 'monitor/enabled')
        for obj in (completion_box, case_comp_box, show_single_box,
                    comp_enter_box, calltips_box):
            self.connect(monitor_box, SIGNAL("toggled(bool)"), obj.setEnabled)
            obj.setEnabled(self.get_option('monitor/enabled'))
        
        monitor_layout = QVBoxLayout()
        monitor_layout.addWidget(monitor_label)
        monitor_layout.addWidget(monitor_box)
        monitor_group.setLayout(monitor_layout)
        
        # Qt Group
        opts = [(_("Default library"), 'default'), ('PyQt4', 'pyqt'),
                ('PySide', 'pyside')]
        qt_group = QGroupBox(_("Qt (PyQt/PySide)"))
        qt_setapi_box = self.create_combobox(
                         _("Qt-Python bindings library selection:"), opts,
                         'qt/api', default='default',
                         tip=_("This option will act on<br> "
                               "libraries such as Matplotlib, guidata "
                               "or ETS"))
        interpreter = self.get_option('pythonexecutable')
        has_pyqt4 = programs.is_module_installed('PyQt4',
                                                 interpreter=interpreter)
        has_pyside = programs.is_module_installed('PySide',
                                                  interpreter=interpreter)
        if has_pyside and not has_pyqt4:
            self.set_option('qt/api', 'pyside')
        
        qt_hook_box = newcb(_("Install Spyder's input hook for Qt"),
                        'qt/install_inputhook',
                        tip=_("PyQt installs an input hook that allows<br> "
                              "creating and interacting with Qt widgets "
                              "in an interactive interpreter without "
                              "blocking it. On Windows platforms, it "
                              "is strongly recommended to replace it "
                              "by Spyder's. Regarding PySide, note that "
                              "it does not install an input hook, so it "
                              "is required to enable this feature in "
                              "order to be able to manipulate PySide/Qt" 
                              "objects interactively."))
        
        qt_layout = QVBoxLayout()
        qt_layout.addWidget(qt_setapi_box)
        qt_layout.addWidget(qt_hook_box)
        qt_group.setLayout(qt_layout)
        qt_group.setEnabled(has_pyqt4 or has_pyside)
        
        # PyQt Group
        if has_pyqt4:
            pyqt_group = QGroupBox(_("PyQt"))
            setapi_box = self.create_combobox(
                _("API selection for QString and QVariant objects:"),
                ((_("Default API"), 0), (_("API #1"), 1), (_("API #2"), 2)),
                'pyqt/api_version', default=0,
                tip=_("PyQt API #1 is the default API for<br>"
                      "Python 2. PyQt API #2 is the default "
                      "API for Python 3 and is compatible with "
                      "PySide. Note that switching to API #2 "
                      "may require to enable the Matplotlib "
                      "patch."))
            ignore_api_box = newcb(_("Ignore API change errors (sip.setapi)"),
                                     'pyqt/ignore_sip_setapi_errors',
                               tip=_("Enabling this option will ignore <br>"
                                     "errors when changing PyQt API. As "
                                     "PyQt does not support dynamic API "
                                     "changes, it is strongly recommended "
                                     "to use this feature wisely, e.g. "
                                     "for debugging purpose."))
            try:
                from sip import setapi #analysis:ignore
            except ImportError:
                setapi_box.setDisabled(True)
                ignore_api_box.setDisabled(True)
            
            pyqt_layout = QVBoxLayout()
            pyqt_layout.addWidget(setapi_box)
            pyqt_layout.addWidget(ignore_api_box)
            pyqt_group.setLayout(pyqt_layout)
            qt_layout.addWidget(pyqt_group)
        
        # Matplotlib Group
        mpl_group = QGroupBox(_("Matplotlib"))
        mpl_backend_box = newcb('', 'matplotlib/backend/enabled', True)
        mpl_backend_edit = self.create_lineedit(_("GUI backend:"),
                                'matplotlib/backend/value', "Qt4Agg",
                                tip=_("Set the GUI toolkit used by <br>"
                                      "Matplotlib to show figures "
                                      "(default: Qt4Agg)"),
                                alignment=Qt.Horizontal)
        self.connect(mpl_backend_box, SIGNAL("toggled(bool)"),
                     mpl_backend_edit.setEnabled)
        mpl_backend_layout = QHBoxLayout()
        mpl_backend_layout.addWidget(mpl_backend_box)
        mpl_backend_layout.addWidget(mpl_backend_edit)
        mpl_backend_edit.setEnabled(
                                self.get_option('matplotlib/backend/enabled'))
        mpl_patch_box = newcb(_("Patch Matplotlib figures"),
                              'matplotlib/patch', False)
        mpl_patch_label = QLabel(_("Patching Matplotlib library will add a "
                                   "button to customize figure options "
                                   "(Qt4Agg only) and fix some issues."))
        mpl_patch_label.setWordWrap(True)
        self.connect(mpl_patch_box, SIGNAL("toggled(bool)"),
                     mpl_patch_label.setEnabled)
        
        mpl_installed = programs.is_module_installed('matplotlib')
        if not is_mpl_patch_available():
            mpl_patch_box.hide()
            mpl_patch_label.hide()
        
        mpl_layout = QVBoxLayout()
        mpl_layout.addLayout(mpl_backend_layout)
        mpl_layout.addWidget(mpl_patch_box)
        mpl_layout.addWidget(mpl_patch_label)
        mpl_group.setLayout(mpl_layout)
        mpl_group.setEnabled(mpl_installed)
        
        # ETS Group
        ets_group = QGroupBox(_("Enthought Tool Suite"))
        ets_label = QLabel(_("Enthought Tool Suite (ETS) supports "
                             "PyQt4 (qt4) and wxPython (wx) graphical "
                             "user interfaces."))
        ets_label.setWordWrap(True)
        ets_edit = self.create_lineedit(_("ETS_TOOLKIT:"), 'ets_backend',
                                        default='qt4', alignment=Qt.Horizontal)
        
        ets_layout = QVBoxLayout()
        ets_layout.addWidget(ets_label)
        ets_layout.addWidget(ets_edit)
        ets_group.setLayout(ets_layout)
        ets_group.setEnabled(programs.is_module_installed(
                                                    "enthought.etsconfig.api",
                                                    interpreter=interpreter))
        
        tabs = QTabWidget()
        tabs.addTab(self.create_tab(font_group, interface_group, display_group,
                                    bg_group),
                    _("Display"))
        tabs.addTab(self.create_tab(monitor_group, source_group),
                    _("Introspection"))
        tabs.addTab(self.create_tab(pyexec_group, startup_group,
                                    pystartup_group, umd_group),
                    _("Advanced settings"))
        tabs.addTab(self.create_tab(qt_group, mpl_group, ets_group),
                    _("External modules"))
        
        vlayout = QVBoxLayout()
        vlayout.addWidget(tabs)
        self.setLayout(vlayout)
    
    def change_pystartup(self, pyexec, def_radio, custom_radio):
        """
        Automatically change to default PYTHONSTARTUP file if scientific libs
        are not available
        """
        if not isinstance(pyexec, basestring):
            pyexec = unicode(pyexec.toUtf8(), 'utf-8')
        old_pyexec = self.get_option("pythonexecutable")
        if not (pyexec == old_pyexec) and custom_radio.isChecked():
            scientific = scientific_libs_available(pyexec)
            if not scientific:
                def_radio.setChecked(True)
                custom_radio.setChecked(False)

    def change_qtapi(self, pyexec):
        """Automatically change qt_api setting after changing interpreter"""
        if not isinstance(pyexec, basestring):
            pyexec = unicode(pyexec.toUtf8(), 'utf-8')
        old_pyexec = self.get_option("pythonexecutable")
        if not (pyexec == old_pyexec):
            has_pyqt4 = programs.is_module_installed('PyQt4',
                                                     interpreter=pyexec)
            has_pyside = programs.is_module_installed('PySide',
                                                      interpreter=pyexec)
            for cb in self.comboboxes:
                if self.comboboxes[cb][0] == 'qt/api':
                    qt_setapi_cb = cb
            if has_pyside and not has_pyqt4:
                qt_setapi_cb.setCurrentIndex(2)
            elif has_pyqt4 and not has_pyside:
                qt_setapi_cb.setCurrentIndex(1)
            else:
                qt_setapi_cb.setCurrentIndex(0)


class ExternalConsole(SpyderPluginWidget):
    """
    Console widget
    """
    CONF_SECTION = 'console'
    CONFIGWIDGET_CLASS = ExternalConsoleConfigPage
    def __init__(self, parent, light_mode):
        SpyderPluginWidget.__init__(self, parent)
        self.light_mode = light_mode
        self.tabwidget = None
        self.menu_actions = None
        
        self.inspector = None # Object inspector plugin
        self.historylog = None # History log plugin
        self.variableexplorer = None # Variable explorer plugin
        
        self.python_count = 0
        self.terminal_count = 0

        try:
            from sip import setapi #analysis:ignore
        except ImportError:
            self.set_option('pyqt/ignore_sip_setapi_errors', False)
        
        executable = self.get_option('pythonexecutable',
                                     get_python_executable())
        if self.get_option('pythonstartup/default', None) is None:
            scientific = scientific_libs_available(executable)
            self.set_option('pythonstartup/default', not scientific)
        if not osp.isfile(self.get_option('pythonstartup', '')):
            scientific = scientific_libs_available(executable)
            self.set_option('pythonstartup', SCIENTIFIC_STARTUP)
            self.set_option('pythonstartup/default', not scientific)
        # default/custom settings are mutually exclusive:
        self.set_option('pythonstartup/custom',
                        not self.get_option('pythonstartup/default'))
        
        if not osp.isfile(executable):
            # This is absolutely necessary, in case the Python interpreter
            # executable has been moved since last Spyder execution (following
            # a Python distribution upgrade for example)
            self.set_option('pythonexecutable', get_python_executable())
        elif executable.endswith('pythonw.exe'):
            # That should not be necessary because this case is already taken
            # care of by the `get_python_executable` function but, this was
            # implemented too late, so we have to fix it here too, in case
            # the Python executable has already been set with pythonw.exe:
            self.set_option('pythonexecutable',
                            executable.replace("pythonw.exe", "python.exe"))
        
        self.shellwidgets = []
        self.filenames = []
        self.icons = []
        self.runfile_args = ""
        
        # Initialize plugin
        self.initialize_plugin()
        
        layout = QVBoxLayout()
        self.tabwidget = Tabs(self, self.menu_actions)
        if hasattr(self.tabwidget, 'setDocumentMode')\
           and not sys.platform == 'darwin':
            # Don't set document mode to true on OSX because it generates
            # a crash when the console is detached from the main window
            # Fixes Issue 561
            self.tabwidget.setDocumentMode(True)
        self.connect(self.tabwidget, SIGNAL('currentChanged(int)'),
                     self.refresh_plugin)
        self.connect(self.tabwidget, SIGNAL('move_data(int,int)'),
                     self.move_tab)
        self.connect(self.main, SIGNAL("pythonpath_changed()"),
                     self.set_path)
                     
        self.tabwidget.set_close_function(self.close_console)

        layout.addWidget(self.tabwidget)
        
        # Find/replace widget
        self.find_widget = FindReplace(self)
        self.find_widget.hide()
        self.register_widget_shortcuts("Editor", self.find_widget)
        
        layout.addWidget(self.find_widget)
        
        self.setLayout(layout)
            
        # Accepting drops
        self.setAcceptDrops(True)
        
    def move_tab(self, index_from, index_to):
        """
        Move tab (tabs themselves have already been moved by the tabwidget)
        """
        filename = self.filenames.pop(index_from)
        shell = self.shellwidgets.pop(index_from)
        icons = self.icons.pop(index_from)
        
        self.filenames.insert(index_to, filename)
        self.shellwidgets.insert(index_to, shell)
        self.icons.insert(index_to, icons)
        self.emit(SIGNAL('update_plugin_title()'))

    def get_shell_index_from_id(self, shell_id):
        """Return shellwidget index from id"""
        for index, shell in enumerate(self.shellwidgets):
            if id(shell) == shell_id:
                return index
        
    def close_console(self, index=None, from_ipyclient=False):
        """Close console tab from index or widget (or close current tab)"""
        # Get tab index
        if not self.tabwidget.count():
            return
        if index is None:
            index = self.tabwidget.currentIndex()
        
        # Detect what widget we are trying to close
        for i, s in enumerate(self.shellwidgets):
            if index == i:
                shellwidget = s
        
        # If the tab is an IPython kernel, try to detect if it has a client
        # connected to it
        if shellwidget.is_ipykernel:
            ipyclients = self.main.ipyconsole.get_clients()
            if ipyclients:
                for ic in ipyclients:
                    if ic.kernel_widget_id == id(shellwidget):
                        connected_ipyclient = True
                        break
                else:
                    connected_ipyclient = False
            else:
                connected_ipyclient = False
        
        # Closing logic
        if not shellwidget.is_ipykernel or from_ipyclient or \
          not connected_ipyclient:
            self.tabwidget.widget(index).close()
            self.tabwidget.removeTab(index)
            self.filenames.pop(index)
            self.shellwidgets.pop(index)
            self.icons.pop(index)
            self.emit(SIGNAL('update_plugin_title()'))
        else:
            QMessageBox.question(self, _('Trying to kill a kernel?'),
                _("You can't close this kernel because it has one or more "
                  "consoles connected to it.<br><br>"
                  "You need to close them instead or you can kill the kernel "
                  "using the button far to the right."),
                  QMessageBox.Ok)
                                 
        
    def set_variableexplorer(self, variableexplorer):
        """Set variable explorer plugin"""
        self.variableexplorer = variableexplorer
    
    def set_path(self):
        """Set consoles PYTHONPATH if changed by the user"""
        from spyderlib.widgets.externalshell import pythonshell
        for sw in self.shellwidgets:
            if isinstance(sw, pythonshell.ExternalPythonShell):
                if sw.is_interpreter and sw.is_running():
                    sw.path = self.main.get_spyder_pythonpath()
                    sw.shell.path = sw.path
        
    def __find_python_shell(self, interpreter_only=False):
        current_index = self.tabwidget.currentIndex()
        if current_index == -1:
            return
        from spyderlib.widgets.externalshell import pythonshell
        for index in [current_index]+range(self.tabwidget.count()):
            shellwidget = self.tabwidget.widget(index)
            if isinstance(shellwidget, pythonshell.ExternalPythonShell):
                if interpreter_only and not shellwidget.is_interpreter:
                    continue
                elif not shellwidget.is_running():
                    continue
                else:
                    self.tabwidget.setCurrentIndex(index)
                    return shellwidget
    
    def get_current_shell(self):
        """
        Called by object inspector to retrieve the current shell instance
        """
        shellwidget = self.__find_python_shell()
        return shellwidget.shell
                
    def get_running_python_shell(self):
        """
        Called by object inspector to retrieve a running Python shell instance
        """
        current_index = self.tabwidget.currentIndex()
        if current_index == -1:
            return
        from spyderlib.widgets.externalshell import pythonshell
        shellwidgets = [self.tabwidget.widget(index)
                        for index in range(self.tabwidget.count())]
        shellwidgets = [_w for _w in shellwidgets
                        if isinstance(_w, pythonshell.ExternalPythonShell) \
                        and _w.is_running()]
        if shellwidgets:
            # First, iterate on interpreters only:
            for shellwidget in shellwidgets:
                if shellwidget.is_interpreter:
                    return shellwidget.shell
            else:
                return shellwidgets[0].shell
        
    def run_script_in_current_shell(self, filename, wdir, args, debug):
        """Run script in current shell, if any"""
        line = "%s(r'%s'" % ('debugfile' if debug else 'runfile',
                             unicode(filename))
        norm = lambda text: remove_trailing_single_backslash(unicode(text))
        if args:
            line += ", args=r'%s'" % norm(args)
        if wdir:
            line += ", wdir=r'%s'" % norm(wdir)
        line += ")"
        if not self.execute_python_code(line, interpreter_only=True):
            QMessageBox.warning(self, _('Warning'),
                _("No Python shell is currently selected to run <b>%s</b>."
                  "<br><br>Please select or open a new Python interpreter "
                  "and try again.") % osp.basename(filename), QMessageBox.Ok)
        else:
            self.visibility_changed(True)
            self.raise_()            
            
    def set_current_shell_working_directory(self, directory):
        """Set current shell working directory"""
        shellwidget = self.__find_python_shell()
        if shellwidget is not None:
            shellwidget.shell.set_cwd(unicode(directory))
        
    def execute_python_code(self, lines, interpreter_only=False):
        """Execute Python code in an already opened Python interpreter"""
        shellwidget = self.__find_python_shell(
                                        interpreter_only=interpreter_only)
        if (shellwidget is not None) and (not shellwidget.is_ipykernel):
            shellwidget.shell.execute_lines(unicode(lines))
            self.activateWindow()
            shellwidget.shell.setFocus()
            return True
        else:
            return False
            
    def pdb_has_stopped(self, fname, lineno, shellwidget):
        """Python debugger has just stopped at frame (fname, lineno)"""      
        # This is a unique form of the edit_goto signal that is intended to 
        # prevent keyboard input from accidentally entering the editor
        # during repeated, rapid entry of debugging commands.    
        self.emit(SIGNAL("edit_goto(QString,int,QString,bool)"),
                  fname, lineno, '',False)
        if shellwidget.is_ipykernel:
            # Focus client widget, not kernel
            ipw = self.main.ipyconsole.get_focus_widget()
            self.main.ipyconsole.activateWindow()
            ipw.setFocus()
        else:
            self.activateWindow()
            shellwidget.shell.setFocus()
        
    def set_spyder_breakpoints(self):
        """Set all Spyder breakpoints into all shells"""
        for shellwidget in self.shellwidgets:
            shellwidget.shell.set_spyder_breakpoints()    
    
    def start(self, fname, wdir=None, args='', interact=False, debug=False,
              python=True, ipykernel=False, ipyclient=False,
              python_args=''):
        """
        Start new console
        
        fname:
          string: filename of script to run
          None: open an interpreter
        wdir: working directory
        args: command line options of the Python script
        interact: inspect script interactively after its execution
        debug: run pdb
        python: True: Python interpreter, False: terminal
        ipykernel: True: IPython kernel
        ipyclient: True: Automatically create an IPython client
        python_args: additionnal Python interpreter command line options
                   (option "-u" is mandatory, see widgets.externalshell package)
        """
        # Note: fname is None <=> Python interpreter
        if fname is not None and not isinstance(fname, basestring):
            fname = unicode(fname)
        if wdir is not None and not isinstance(wdir, basestring):
            wdir = unicode(wdir)
        
        if fname is not None and fname in self.filenames:
            index = self.filenames.index(fname)
            if self.get_option('single_tab'):
                old_shell = self.shellwidgets[index]
                if old_shell.is_running():
                    answer = QMessageBox.question(self, self.get_plugin_title(),
                        _("%s is already running in a separate process.\n"
                          "Do you want to kill the process before starting "
                          "a new one?") % osp.basename(fname),
                        QMessageBox.Yes | QMessageBox.Cancel)
                    if answer == QMessageBox.Yes:
                        old_shell.process.kill()
                        old_shell.process.waitForFinished()
                    else:
                        return
                self.close_console(index)
        else:
            index = self.tabwidget.count()

        # Creating a new external shell
        pythonpath = self.main.get_spyder_pythonpath()
        light_background = self.get_option('light_background')
        show_elapsed_time = self.get_option('show_elapsed_time')
        if python:
            pythonexecutable = self.get_option('pythonexecutable')
            if self.get_option('pythonstartup/default', True):
                pythonstartup = None
            else:
                pythonstartup = self.get_option('pythonstartup', None)
            monitor_enabled = self.get_option('monitor/enabled')
            mpl_patch_enabled = is_mpl_patch_available() and\
                                self.get_option('matplotlib/patch')
            if self.get_option('matplotlib/backend/enabled'):
                mpl_backend = self.get_option('matplotlib/backend/value')
            else:
                mpl_backend = None
            ets_backend = self.get_option('ets_backend', 'qt4')
            qt_api = self.get_option('qt/api')
            if qt_api not in ('pyqt', 'pyside'):
                qt_api = None
            install_qt_inputhook = self.get_option('qt/install_inputhook')
            pyqt_api = self.get_option('pyqt/api_version', 0)
            ignore_sip_setapi_errors = self.get_option(
                                            'pyqt/ignore_sip_setapi_errors')
            merge_output_channels = self.get_option('merge_output_channels')
            colorize_sys_stderr = self.get_option('colorize_sys_stderr')
            umd_enabled = self.get_option('umd/enabled')
            umd_namelist = self.get_option('umd/namelist')
            umd_verbose = self.get_option('umd/verbose')
            ar_timeout = CONF.get('variable_explorer', 'autorefresh/timeout')
            ar_state = CONF.get('variable_explorer', 'autorefresh')
            if self.light_mode:
                from spyderlib.plugins.variableexplorer import VariableExplorer
                sa_settings = VariableExplorer.get_settings()
            else:
                sa_settings = None
            shellwidget = ExternalPythonShell(self, fname, wdir,
                           interact, debug, path=pythonpath,
                           python_args=python_args,
                           ipykernel=ipykernel,
                           arguments=args, stand_alone=sa_settings,
                           pythonstartup=pythonstartup,
                           pythonexecutable=pythonexecutable,
                           umd_enabled=umd_enabled, umd_namelist=umd_namelist,
                           umd_verbose=umd_verbose, ets_backend=ets_backend,
                           monitor_enabled=monitor_enabled,
                           mpl_patch_enabled=mpl_patch_enabled,
                           mpl_backend=mpl_backend,
                           qt_api=qt_api, pyqt_api=pyqt_api,
                           install_qt_inputhook=install_qt_inputhook,
                           ignore_sip_setapi_errors=ignore_sip_setapi_errors,
                           merge_output_channels=merge_output_channels,
                           colorize_sys_stderr=colorize_sys_stderr,
                           autorefresh_timeout=ar_timeout,
                           autorefresh_state=ar_state,
                           light_background=light_background,
                           menu_actions=self.menu_actions,
                           show_buttons_inside=False,
                           show_elapsed_time=show_elapsed_time)
            self.connect(shellwidget, SIGNAL('pdb(QString,int)'),
                         lambda fname, lineno, shellwidget=shellwidget:
                         self.pdb_has_stopped(fname, lineno, shellwidget))
            self.register_widget_shortcuts("Console", shellwidget.shell)
        else:
            if os.name == 'posix':
                cmd = 'gnome-terminal'
                args = []
                if programs.is_program_installed(cmd):
                    if wdir:
                        args.extend(['--working-directory=%s' % wdir])
                    programs.run_program(cmd, args)
                    return
                cmd = 'konsole'
                if programs.is_program_installed(cmd):
                    if wdir:
                        args.extend(['--workdir', wdir])
                    programs.run_program(cmd, args)
                    return
            shellwidget = ExternalSystemShell(self, wdir, path=pythonpath,
                                          light_background=light_background,
                                          menu_actions=self.menu_actions,
                                          show_buttons_inside=False,
                                          show_elapsed_time=show_elapsed_time)
        
        # Code completion / calltips
        shellwidget.shell.setMaximumBlockCount(
                                            self.get_option('max_line_count') )
        shellwidget.shell.set_font( self.get_plugin_font() )
        shellwidget.shell.toggle_wrap_mode( self.get_option('wrap') )
        shellwidget.shell.set_calltips( self.get_option('calltips') )
        shellwidget.shell.set_codecompletion_auto(
                            self.get_option('codecompletion/auto') )
        shellwidget.shell.set_codecompletion_case(
                            self.get_option('codecompletion/case_sensitive') )
        shellwidget.shell.set_codecompletion_single(
                            self.get_option('codecompletion/show_single') )
        shellwidget.shell.set_codecompletion_enter(
                            self.get_option('codecompletion/enter_key') )
        if python and self.inspector is not None:
            shellwidget.shell.set_inspector(self.inspector)
            shellwidget.shell.set_inspector_enabled(
                                            self.get_option('object_inspector'))
        if self.historylog is not None:
            self.historylog.add_history(shellwidget.shell.history_filename)
            self.connect(shellwidget.shell,
                         SIGNAL('append_to_history(QString,QString)'),
                         self.historylog.append_to_history)
        self.connect(shellwidget.shell, SIGNAL("go_to_error(QString)"),
                     self.go_to_error)
        self.connect(shellwidget.shell, SIGNAL("focus_changed()"),
                     lambda: self.emit(SIGNAL("focus_changed()")))
        if python:
            if self.main.editor is not None:
                self.connect(shellwidget, SIGNAL('open_file(QString,int)'),
                             self.open_file_in_spyder)
            if fname is None:
                if ipykernel:
                    tab_name = _("Kernel")
                    tab_icon1 = get_icon('ipython_console.png')
                    tab_icon2 = get_icon('ipython_console_t.png')
                    if ipyclient:
                        self.connect(shellwidget,
                                 SIGNAL('create_ipython_client(QString)'),
                                 lambda cf: self.create_ipyclient(
                                         cf, kernel_widget=shellwidget))
                else:
                    self.python_count += 1
                    tab_name = "Python %d" % self.python_count
                    tab_icon1 = get_icon('python.png')
                    tab_icon2 = get_icon('python_t.png')
            else:
                tab_name = osp.basename(fname)
                tab_icon1 = get_icon('run.png')
                tab_icon2 = get_icon('terminated.png')
        else:
            fname = id(shellwidget)
            if os.name == 'nt':
                tab_name = _("Command Window")
            else:
                tab_name = _("Terminal")
            self.terminal_count += 1
            tab_name += (" %d" % self.terminal_count)
            tab_icon1 = get_icon('cmdprompt.png')
            tab_icon2 = get_icon('cmdprompt_t.png')
        self.shellwidgets.insert(index, shellwidget)
        self.filenames.insert(index, fname)
        self.icons.insert(index, (tab_icon1, tab_icon2))
        if index is None:
            index = self.tabwidget.addTab(shellwidget, tab_name)
        else:
            self.tabwidget.insertTab(index, shellwidget, tab_name)
        
        self.connect(shellwidget, SIGNAL("started()"),
                     lambda sid=id(shellwidget): self.process_started(sid))
        self.connect(shellwidget, SIGNAL("finished()"),
                     lambda sid=id(shellwidget): self.process_finished(sid))
        self.find_widget.set_editor(shellwidget.shell)
        self.tabwidget.setTabToolTip(index, fname if wdir is None else wdir)
        self.tabwidget.setCurrentIndex(index)
        if self.dockwidget and not self.ismaximized and not ipykernel:
            self.dockwidget.setVisible(True)
            self.dockwidget.raise_()
        
        shellwidget.set_icontext_visible(self.get_option('show_icontext'))
        
        # Start process and give focus to console
        shellwidget.start_shell()
        if not ipykernel:
            self.activateWindow()
            shellwidget.shell.setFocus()
    
    def set_ipykernel_attrs(self, connection_file, kernel_widget):
        """Add the pid of the kernel process to an IPython kernel tab"""
        # Set connection file
        kernel_widget.connection_file = connection_file
        
        # If we've reached this point then it's safe to assume IPython
        # is available, and this import should be valid.
        from IPython.core.application import get_ipython_dir
        # For each kernel we launch, setup to delete the associated
        # connection file at the time Spyder exits.
        def cleanup_connection_file(connection_file):
            connection_file = osp.join(get_ipython_dir(), 'profile_default',
                                   'security', connection_file)
            try:
                os.remove(connection_file)
            except OSError:
                pass
        atexit.register(cleanup_connection_file, connection_file)            
        
        # Set tab name
        index = self.get_shell_index_from_id(id(kernel_widget))
        match = re.match('^kernel-(\d+).json', connection_file)
        if match is not None:  # should not fail, but we never know...
            text = unicode(self.tabwidget.tabText(index))
            name = "%s %s" % (text, match.groups()[0])
            self.tabwidget.setTabText(index, name)
    
    def create_ipyclient(self, connection_file, kernel_widget):
        """Create a new IPython client connected to a kernel just started"""
        self.set_ipykernel_attrs(connection_file, kernel_widget)
        self.main.ipyconsole.new_client(connection_file, id(kernel_widget))
        # QApplication.restoreOverrideCursor()  # Stop busy cursor indication
        # QApplication.processEvents()
        
    def open_file_in_spyder(self, fname, lineno):
        """Open file in Spyder's editor from remote process"""
        self.main.editor.activateWindow()
        self.main.editor.raise_()
        self.main.editor.load(fname, lineno)
        
    #------ Private API -------------------------------------------------------
    def process_started(self, shell_id):
        index = self.get_shell_index_from_id(shell_id)
        shell = self.shellwidgets[index]
        icon, _icon = self.icons[index]
        self.tabwidget.setTabIcon(index, icon)
        if self.inspector is not None:
            self.inspector.set_shell(shell.shell)
        if self.variableexplorer is not None:
            self.variableexplorer.add_shellwidget(shell)
        
    def process_finished(self, shell_id):
        index = self.get_shell_index_from_id(shell_id)
        if index is not None:
            # Not sure why it happens, but sometimes the shellwidget has 
            # already been removed, so that's not bad if we can't change
            # the tab icon...
            _icon, icon = self.icons[index]
            self.tabwidget.setTabIcon(index, icon)
        if self.variableexplorer is not None:
            self.variableexplorer.remove_shellwidget(shell_id)
        
    #------ SpyderPluginWidget API --------------------------------------------
    def get_plugin_title(self):
        """Return widget title"""
        title = _('Console')
        if self.filenames:
            index = self.tabwidget.currentIndex()
            fname = self.filenames[index]
            if fname:
                title += ' - '+unicode(fname)
        return title
    
    def get_plugin_icon(self):
        """Return widget icon"""
        return get_icon('console.png')
    
    def get_focus_widget(self):
        """
        Return the widget to give focus to when
        this plugin's dockwidget is raised on top-level
        """
        return self.tabwidget.currentWidget()
        
    def get_plugin_actions(self):
        """Return a list of actions related to plugin"""
        interpreter_action = create_action(self,
                            _("Open a Python &interpreter"), None,
                            'python.png', triggered=self.open_interpreter)
        if os.name == 'nt':
            text = _("Open &command prompt")
            tip = _("Open a Windows command prompt")
        else:
            text = _("Open &terminal")
            tip = _("Open a terminal window inside Spyder")
        terminal_action = create_action(self, text, None, 'cmdprompt.png', tip,
                                        triggered=self.open_terminal)
        run_action = create_action(self,
                            _("&Run..."), None,
                            'run_small.png', _("Run a Python script"),
                            triggered=self.run_script)

        interact_menu_actions = [interpreter_action]
        tools_menu_actions = [terminal_action]
        self.menu_actions = [interpreter_action, terminal_action, run_action]
        
        self.main.interact_menu_actions += interact_menu_actions
        self.main.tools_menu_actions += tools_menu_actions
        
        return self.menu_actions+interact_menu_actions+tools_menu_actions
    
    def register_plugin(self):
        """Register plugin in Spyder's main window"""
        if self.main.light:
            self.main.setCentralWidget(self)
            self.main.widgetlist.append(self)
        else:
            self.main.add_dockwidget(self)
            self.inspector = self.main.inspector
            if self.inspector is not None:
                self.inspector.set_external_console(self)
            self.historylog = self.main.historylog
            self.connect(self, SIGNAL("edit_goto(QString,int,QString)"),
                         self.main.editor.load)
            self.connect(self, SIGNAL("edit_goto(QString,int,QString,bool)"),
                         lambda fname, lineno, word, processevents:
                         self.main.editor.load(fname,lineno,word,
                                               processevents=processevents))
            self.connect(self.main.editor,
                         SIGNAL('run_in_current_extconsole(QString,QString,QString,bool)'),
                         self.run_script_in_current_shell)
            self.connect(self.main.editor,
                         SIGNAL("breakpoints_saved()"),
                         self.set_spyder_breakpoints)
            self.connect(self.main.editor, SIGNAL("open_dir(QString)"),
                         self.set_current_shell_working_directory)
            self.connect(self.main.workingdirectory,
                         SIGNAL("set_current_console_wd(QString)"),
                         self.set_current_shell_working_directory)
            self.connect(self, SIGNAL('focus_changed()'),
                         self.main.plugin_focus_changed)
            self.connect(self, SIGNAL('redirect_stdio(bool)'),
                         self.main.redirect_internalshell_stdio)
            expl = self.main.explorer
            if expl is not None:
                self.connect(expl, SIGNAL("open_terminal(QString)"),
                             self.open_terminal)
                self.connect(expl, SIGNAL("open_interpreter(QString)"),
                             self.open_interpreter)
            pexpl = self.main.projectexplorer
            if pexpl is not None:
                self.connect(pexpl, SIGNAL("open_terminal(QString)"),
                             self.open_terminal)
                self.connect(pexpl, SIGNAL("open_interpreter(QString)"),
                             self.open_interpreter)
        
    def closing_plugin(self, cancelable=False):
        """Perform actions before parent main window is closed"""
        for shellwidget in self.shellwidgets:
            shellwidget.close()
        return True
    
    def refresh_plugin(self):
        """Refresh tabwidget"""
        shellwidget = None
        if self.tabwidget.count():
            shellwidget = self.tabwidget.currentWidget()
            editor = shellwidget.shell
            editor.setFocus()
            widgets = [shellwidget.create_time_label(), 5
                       ]+shellwidget.get_toolbar_buttons()+[5]
        else:
            editor = None
            widgets = []
        self.find_widget.set_editor(editor)
        self.tabwidget.set_corner_widgets({Qt.TopRightCorner: widgets})
        if shellwidget:
            shellwidget.update_time_label_visibility()
        self.main.last_console_plugin_focus_was_python = True
        self.emit(SIGNAL('update_plugin_title()'))
    
    def apply_plugin_settings(self, options):
        """Apply configuration file's plugin settings"""
        font = self.get_plugin_font()
        showtime = self.get_option('show_elapsed_time')
        icontext = self.get_option('show_icontext')
        calltips = self.get_option('calltips')
        inspector = self.get_option('object_inspector')
        wrap = self.get_option('wrap')
        compauto = self.get_option('codecompletion/auto')
        case_comp = self.get_option('codecompletion/case_sensitive')
        show_single = self.get_option('codecompletion/show_single')
        compenter = self.get_option('codecompletion/enter_key')
        mlc = self.get_option('max_line_count')
        for shellwidget in self.shellwidgets:
            shellwidget.shell.set_font(font)
            shellwidget.set_elapsed_time_visible(showtime)
            shellwidget.set_icontext_visible(icontext)
            shellwidget.shell.set_calltips(calltips)
            if isinstance(shellwidget.shell, ExternalPythonShell):
                shellwidget.shell.set_inspector_enabled(inspector)
            shellwidget.shell.toggle_wrap_mode(wrap)
            shellwidget.shell.set_codecompletion_auto(compauto)
            shellwidget.shell.set_codecompletion_case(case_comp)
            shellwidget.shell.set_codecompletion_single(show_single)
            shellwidget.shell.set_codecompletion_enter(compenter)
            shellwidget.shell.setMaximumBlockCount(mlc)
    
    #------ Public API ---------------------------------------------------------
    def open_interpreter_at_startup(self):
        """Open an interpreter or an IPython kernel at startup"""
        if self.get_option('open_python_at_startup', True):
            self.open_interpreter()
        if CONF.get('ipython_console', 'open_ipython_at_startup', False):
            if self.main.ipyconsole is None:
                suffix = SUPPORTED_IPYTHON.replace(';', _(' and ')
                                         ).replace('<', '&lt;'
                                         ).replace('>', '&gt;')
                if programs.is_module_installed('IPython'):
                    import IPython
                    suffix += _('<br><u>Installed version</u>: %s'
                                ) % IPython.__version__
                QMessageBox.critical(self, _('IPython console'),
                    _("Unable to open IPython console because no supported "
                      "IPython version was found.<br><br>"
                      "<u>Supported IPython versions</u>: %s") % suffix,
                    QMessageBox.Ok)
                if not self.get_option('open_python_at_startup'):
                    self.open_interpreter()
            else:
                self.start_ipykernel()

    def open_interpreter(self, wdir=None):
        """Open interpreter"""
        if wdir is None:
            wdir = os.getcwdu()
        if not self.main.light:
            self.visibility_changed(True)
        self.start(fname=None, wdir=unicode(wdir), args='',
                   interact=True, debug=False, python=True)
        
    def start_ipykernel(self, wdir=None, create_client=True):
        """Start new IPython kernel"""
        if create_client and not self.get_option('monitor/enabled'):
            QMessageBox.warning(self, _('Open an IPython console'),
                _("The console monitor was disabled: the IPython kernel will "
                  "be started as expected, but an IPython console will have "
                  "to be connected manually to the kernel."), QMessageBox.Ok)
        
        # Add a WaitCursor visual indication, because it takes too much time
        # to display a new console (3 to 5 secs). It's stopped in
        # create_ipyclient
        # QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
        # QApplication.processEvents()
        
        if wdir is None:
            wdir = os.getcwdu()
        self.main.ipyconsole.visibility_changed(True)
        self.start(fname=None, wdir=unicode(wdir), args='',
                   interact=True, debug=False, python=True,
                   ipykernel=True, ipyclient=create_client)

    def open_terminal(self, wdir=None):
        """Open terminal"""
        if wdir is None:
            wdir = os.getcwdu()
        self.start(fname=None, wdir=unicode(wdir), args='',
                   interact=True, debug=False, python=False)
        
    def run_script(self):
        """Run a Python script"""
        self.emit(SIGNAL('redirect_stdio(bool)'), False)
        filename, _selfilter = getopenfilename(self, _("Run Python script"),
                os.getcwdu(), _("Python scripts")+" (*.py ; *.pyw ; *.ipy)")
        self.emit(SIGNAL('redirect_stdio(bool)'), True)
        if filename:
            self.start(fname=filename, wdir=None, args='',
                       interact=False, debug=False)
        
    def set_umd_namelist(self):
        """Set UMD excluded modules name list"""
        arguments, valid = QInputDialog.getText(self, _('UMD'),
                                  _('UMD excluded modules:\n'
                                          '(example: guidata, guiqwt)'),
                                  QLineEdit.Normal,
                                  ", ".join(self.get_option('umd/namelist')))
        if valid:
            arguments = unicode(arguments)
            if arguments:
                namelist = arguments.replace(' ', '').split(',')
                fixed_namelist = [module_name for module_name in namelist
                                  if programs.is_module_installed(module_name)]
                invalid = ", ".join(set(namelist)-set(fixed_namelist))
                if invalid:
                    QMessageBox.warning(self, _('UMD'),
                                        _("The following modules are not "
                                          "installed on your machine:\n%s"
                                          ) % invalid, QMessageBox.Ok)
                QMessageBox.information(self, _('UMD'),
                                    _("Please note that these changes will "
                                      "be applied only to new Python/IPython "
                                      "interpreters"), QMessageBox.Ok)
            else:
                fixed_namelist = []
            self.set_option('umd/namelist', fixed_namelist)
        
    def go_to_error(self, text):
        """Go to error if relevant"""
        match = get_error_match(unicode(text))
        if match:
            fname, lnb = match.groups()
            self.emit(SIGNAL("edit_goto(QString,int,QString)"),
                      osp.abspath(fname), int(lnb), '')
            
    #----Drag and drop
    def dragEnterEvent(self, event):
        """Reimplement Qt method
        Inform Qt about the types of data that the widget accepts"""
        source = event.mimeData()
        if source.hasUrls():
            if mimedata2url(source):
                pathlist = mimedata2url(source)
                shellwidget = self.tabwidget.currentWidget()
                if all([is_python_script(unicode(qstr)) for qstr in pathlist]):
                    event.acceptProposedAction()
                elif shellwidget is None or not shellwidget.is_running():
                    event.ignore()
                else:
                    event.acceptProposedAction()
            else:
                event.ignore()
        elif source.hasText():
            event.acceptProposedAction()            
            
    def dropEvent(self, event):
        """Reimplement Qt method
        Unpack dropped data and handle it"""
        source = event.mimeData()
        shellwidget = self.tabwidget.currentWidget()
        if source.hasText():
            qstr = source.text()
            if is_python_script(unicode(qstr)):
                self.start(qstr)
            elif shellwidget:
                shellwidget.shell.insert_text(qstr)
        elif source.hasUrls():
            pathlist = mimedata2url(source)
            if all([is_python_script(unicode(qstr)) for qstr in pathlist]):
                for fname in pathlist:
                    self.start(fname)
            elif shellwidget:
                shellwidget.shell.drop_pathlist(pathlist)
        event.acceptProposedAction()

