# Source code for pyqtgraph.console.Console

    from ..Qt import QtCore, QtGui, USE_PYSIDE
    import sys, re, os, time, traceback, subprocess
    if USE_PYSIDE:
        from . import template_pyside as template
    else:
        from . import template_pyqt as template

    from .. import exceptionHandling as exceptionHandling
    import pickle
    from .. import getConfigOption

    class ConsoleWidget(QtGui.QWidget):
        """
        Widget displaying console output and accepting command input.
        Implements:

        - eval python expressions / exec python statements
        - storable history of commands
        - exception handling allowing commands to be interpreted in the context of any level in the exception stack frame

        Why not just use python in an interactive shell (or ipython) ? There are a few reasons:

        - pyside does not yet allow Qt event processing and interactive shell at the same time
        - on some systems, typing in the console _blocks_ the qt event loop until the user presses enter. This can
          be baffling and frustrating to users since it would appear the program has frozen.
        - some terminals (eg windows cmd.exe) have notoriously unfriendly interfaces
        - ability to add extra features like exception stack introspection
        - ability to have multiple interactive prompts, including for spawned sub-processes
        """

        def __init__(self, parent=None, namespace=None, historyFile=None, text=None, editor=None):
            """
            ==============  ============================================================================
            **Arguments:**
            namespace       dictionary containing the initial variables present in the default namespace
            historyFile     optional file for storing command history
            text            initial text to display in the console window
            editor          optional string for invoking code editor (called when stack trace entries are
                            double-clicked). May contain {fileName} and {lineNum} format keys. Example::

                                editorCommand --loadfile {fileName} --gotoline {lineNum}
            ==============  =============================================================================
            """
            QtGui.QWidget.__init__(self, parent)
            if namespace is None:
                namespace = {}
            self.localNamespace = namespace
            self.editor = editor
            self.multiline = None
            self.inCmd = False

            self.ui = template.Ui_Form()
            self.ui.setupUi(self)
            self.output = self.ui.output
            self.input = self.ui.input
            self.input.setFocus()

            if text is not None:
                self.output.setPlainText(text)

            self.historyFile = historyFile

            history = self.loadHistory()
            if history is not None:
                self.input.history = [""] + history
                self.ui.historyList.addItems(history[::-1])
            self.ui.historyList.hide()
            self.ui.exceptionGroup.hide()

            self.input.sigExecuteCmd.connect(self.runCmd)
            self.ui.historyBtn.toggled.connect(self.ui.historyList.setVisible)
            self.ui.historyList.itemClicked.connect(self.cmdSelected)
            self.ui.historyList.itemDoubleClicked.connect(self.cmdDblClicked)
            self.ui.exceptionBtn.toggled.connect(self.ui.exceptionGroup.setVisible)

            self.ui.catchAllExceptionsBtn.toggled.connect(self.catchAllExceptions)
            self.ui.catchNextExceptionBtn.toggled.connect(self.catchNextException)
            self.ui.clearExceptionBtn.clicked.connect(self.clearExceptionClicked)
            self.ui.exceptionStackList.itemClicked.connect(self.stackItemClicked)
            self.ui.exceptionStackList.itemDoubleClicked.connect(self.stackItemDblClicked)
            self.ui.onlyUncaughtCheck.toggled.connect(self.updateSysTrace)

            self.currentTraceback = None

        def loadHistory(self):
            """Return the list of previously-invoked command strings (or None)."""
            if self.historyFile is not None:
                return pickle.load(open(self.historyFile, 'rb'))

        def saveHistory(self, history):
            """Store the list of previously-invoked command strings."""
            if self.historyFile is not None:
                pickle.dump(open(self.historyFile, 'wb'), history)

        def runCmd(self, cmd):
            #cmd = str(self.input.lastCmd)
            self.stdout = sys.stdout
            self.stderr = sys.stderr
            encCmd = re.sub(r'>', '&gt;', re.sub(r'<', '&lt;', cmd))
            encCmd = re.sub(r' ', '&nbsp;', encCmd)

            self.ui.historyList.addItem(cmd)
            self.saveHistory(self.input.history[1:100])

            try:
                sys.stdout = self
                sys.stderr = self
                if self.multiline is not None:
                    self.write("<br><b>%s</b>\n"%encCmd, html=True)
                    self.execMulti(cmd)
                else:
                    self.write("<br><div style='background-color: #CCF'><b>%s</b>\n"%encCmd, html=True)
                    self.inCmd = True
                    self.execSingle(cmd)

                if not self.inCmd:
                    self.write("</div>\n", html=True)

            finally:
                sys.stdout = self.stdout
                sys.stderr = self.stderr

                sb = self.output.verticalScrollBar()
                sb.setValue(sb.maximum())
                sb = self.ui.historyList.verticalScrollBar()
                sb.setValue(sb.maximum())

        def globals(self):
            frame = self.currentFrame()
            if frame is not None and self.ui.runSelectedFrameCheck.isChecked():
                return self.currentFrame().tb_frame.f_globals
            else:
                return globals()

        def locals(self):
            frame = self.currentFrame()
            if frame is not None and self.ui.runSelectedFrameCheck.isChecked():
                return self.currentFrame().tb_frame.f_locals
            else:
                return self.localNamespace

        def currentFrame(self):
            ## Return the currently selected exception stack frame (or None if there is no exception)
            if self.currentTraceback is None:
                return None
            index = self.ui.exceptionStackList.currentRow()
            tb = self.currentTraceback
            for i in range(index):
                tb = tb.tb_next
            return tb

        def execSingle(self, cmd):
            try:
                output = eval(cmd, self.globals(), self.locals())
                self.write(repr(output) + '\n')
            except SyntaxError:
                try:
                    exec(cmd, self.globals(), self.locals())
                except SyntaxError as exc:
                    if 'unexpected EOF' in exc.msg:
                        self.multiline = cmd
                    else:
                        self.displayException()
                except:
                    self.displayException()
            except:
                self.displayException()

        def execMulti(self, nextLine):
            #self.stdout.write(nextLine+"\n")
            if nextLine.strip() != '':
                self.multiline += "\n" + nextLine
                return
            else:
                cmd = self.multiline

            try:
                output = eval(cmd, self.globals(), self.locals())
                self.write(str(output) + '\n')
                self.multiline = None
            except SyntaxError:
                try:
                    exec(cmd, self.globals(), self.locals())
                    self.multiline = None
                except SyntaxError as exc:
                    if 'unexpected EOF' in exc.msg:
                        self.multiline = cmd
                    else:
                        self.displayException()
                        self.multiline = None
                except:
                    self.displayException()
                    self.multiline = None
            except:
                self.displayException()
                self.multiline = None

        def write(self, strn, html=False):
            self.output.moveCursor(QtGui.QTextCursor.End)
            if html:
                self.output.textCursor().insertHtml(strn)
            else:
                if self.inCmd:
                    self.inCmd = False
                    self.output.textCursor().insertHtml("</div><br><div style='font-weight: normal; background-color: #FFF;'>")
                    #self.stdout.write("</div><br><div style='font-weight: normal; background-color: #FFF;'>")
                self.output.insertPlainText(strn)
            #self.stdout.write(strn)

        def displayException(self):
            """
            Display the current exception and stack.
            """
            tb = traceback.format_exc()
            lines = []
            indent = 4
            prefix = ''
            for l in tb.split('\n'):
                lines.append(" "*indent + prefix + l)
            self.write('\n'.join(lines))
            self.exceptionHandler(*sys.exc_info())

        def cmdSelected(self, item):
            index = -(self.ui.historyList.row(item)+1)
            self.input.setHistory(index)
            self.input.setFocus()

        def cmdDblClicked(self, item):
            index = -(self.ui.historyList.row(item)+1)
            self.input.setHistory(index)
            self.input.execCmd()

        def flush(self):
            pass

        def catchAllExceptions(self, catch=True):
            """
            If True, the console will catch all unhandled exceptions and display the stack
            trace. Each exception caught clears the last.
            """
            self.ui.catchAllExceptionsBtn.setChecked(catch)
            if catch:
                self.ui.catchNextExceptionBtn.setChecked(False)
                self.enableExceptionHandling()
                self.ui.exceptionBtn.setChecked(True)
            else:
                self.disableExceptionHandling()

        def catchNextException(self, catch=True):
            """
            If True, the console will catch the next unhandled exception and display the stack
            trace.
            """
            self.ui.catchNextExceptionBtn.setChecked(catch)
            if catch:
                self.ui.catchAllExceptionsBtn.setChecked(False)
                self.enableExceptionHandling()
                self.ui.exceptionBtn.setChecked(True)
            else:
                self.disableExceptionHandling()

        def enableExceptionHandling(self):
            exceptionHandling.register(self.exceptionHandler)
            self.updateSysTrace()

        def disableExceptionHandling(self):
            exceptionHandling.unregister(self.exceptionHandler)
            self.updateSysTrace()

        def clearExceptionClicked(self):
            self.currentTraceback = None
            self.ui.exceptionInfoLabel.setText("[No current exception]")
            self.ui.exceptionStackList.clear()
            self.ui.clearExceptionBtn.setEnabled(False)

        def stackItemClicked(self, item):
            pass

        def stackItemDblClicked(self, item):
            editor = self.editor
            if editor is None:
                editor = getConfigOption('editorCommand')
            if editor is None:
                return
            tb = self.currentFrame()
            lineNum = tb.tb_lineno
            fileName = tb.tb_frame.f_code.co_filename
            subprocess.Popen(self.editor.format(fileName=fileName, lineNum=lineNum), shell=True)

        #def allExceptionsHandler(self, *args):
            #self.exceptionHandler(*args)

        #def nextExceptionHandler(self, *args):
            #self.ui.catchNextExceptionBtn.setChecked(False)
            #self.exceptionHandler(*args)

        def updateSysTrace(self):
            ## Install or uninstall  sys.settrace handler

            if not self.ui.catchNextExceptionBtn.isChecked() and not self.ui.catchAllExceptionsBtn.isChecked():
                if sys.gettrace() == self.systrace:
                    sys.settrace(None)
                return

            if self.ui.onlyUncaughtCheck.isChecked():
                if sys.gettrace() == self.systrace:
                    sys.settrace(None)
            else:
                if sys.gettrace() is not None and sys.gettrace() != self.systrace:
                    self.ui.onlyUncaughtCheck.setChecked(False)
                    raise Exception("sys.settrace is in use; cannot monitor for caught exceptions.")
                else:
                    sys.settrace(self.systrace)

        def exceptionHandler(self, excType, exc, tb):
            if self.ui.catchNextExceptionBtn.isChecked():
                self.ui.catchNextExceptionBtn.setChecked(False)
            elif not self.ui.catchAllExceptionsBtn.isChecked():
                return

            self.ui.clearExceptionBtn.setEnabled(True)
            self.currentTraceback = tb

            excMessage = ''.join(traceback.format_exception_only(excType, exc))
            self.ui.exceptionInfoLabel.setText(excMessage)
            self.ui.exceptionStackList.clear()
            for index, line in enumerate(traceback.extract_tb(tb)):
                self.ui.exceptionStackList.addItem('File "%s", line %s, in %s()\n  %s' % line)

        def systrace(self, frame, event, arg):
            if event == 'exception' and self.checkException(*arg):
                self.exceptionHandler(*arg)
            return self.systrace

        def checkException(self, excType, exc, tb):
            ## Return True if the exception is interesting; False if it should be ignored.

            filename = tb.tb_frame.f_code.co_filename
            function = tb.tb_frame.f_code.co_name

            filterStr = str(self.ui.filterText.text())
            if filterStr != '':
                if isinstance(exc, Exception):
                    msg = exc.message
                elif isinstance(exc, basestring):
                    msg = exc
                else:
                    msg = repr(exc)
                match = re.search(filterStr, "%s:%s:%s" % (filename, function, msg))
                return match is not None

            ## Go through a list of common exception points we like to ignore:
            if excType is GeneratorExit or excType is StopIteration:
                return False
            if excType is KeyError:
                if filename.endswith('python2.7/weakref.py') and function in ('__contains__', 'get'):
                    return False
                if filename.endswith('python2.7/copy.py') and function == '_keep_alive':
                    return False
            if excType is AttributeError:
                if filename.endswith('python2.7/collections.py') and function == '__init__':
                    return False
                if filename.endswith('numpy/core/fromnumeric.py') and function in ('all', '_wrapit', 'transpose', 'sum'):
                    return False
                if filename.endswith('numpy/core/arrayprint.py') and function in ('_array2string'):
                    return False
                if filename.endswith('MetaArray.py') and function == '__getattr__':
                    for name in ('__array_interface__', '__array_struct__', '__array__'):  ## numpy looks for these when converting objects to array
                        if name in exc:
                            return False
                if filename.endswith('flowchart/eq.py'):
                    return False
                if filename.endswith('pyqtgraph/functions.py') and function == 'makeQImage':
                    return False
            if excType is TypeError:
                if filename.endswith('numpy/lib/function_base.py') and function == 'iterable':
                    return False
            if excType is ZeroDivisionError:
                if filename.endswith('python2.7/traceback.py'):
                    return False

            return True