import sys
from cStringIO import StringIO

from PyQt4.QtCore import *
from PyQt4.QtGui import *

from sface.config import config

import time

class LogIO(QObject):
    def __init__(self, parent, old_stdout):
        QObject.__init__(self, parent)
        self.io = StringIO()
        self.old_stdout = old_stdout

    def write(self, txt):
        self.io.write(txt)
        self.parent().update()

    def getText(self):
        val = self.io.getvalue()
        # looks like there is no other way
        # to empty the StringIO
        del self.io
        self.io = StringIO()
        return val

class LogWindow(QDialog):
    def __init__(self, parent=None):
        QWidget.__init__(self, parent)
        self.setWindowTitle("SFI Log")
        self.text = QTextBrowser(self)
        self.text.ensureCursorVisible()

        layout = QVBoxLayout()
        layout.addWidget(self.text)
        self.setLayout(layout)

        self.logio = LogIO(self, sys.stdout)

    def redirectOutput(self):
        print "\n\nRedirecting all output to Log Window. Please open the log window to see the output\n"
        self.old_stdout = sys.stdout
        self.old_stderr = sys.stderr
        sys.stdout = self.logio
        sys.stderr = self.logio

    def update(self):
        self.text.insertPlainText(self.logio.getText())
        c = self.text.textCursor()
        c.movePosition(QTextCursor.End)
        self.text.setTextCursor(c)