"""Extension to execute code outside the Python shell window.

This adds the following commands:

- Check module does a full syntax check of the current module.
  It also runs the tabnanny to catch any inconsistent tabs.

- Run module executes the module's code in the __main__ namespace.  The window
  must have been saved previously. The module is added to sys.modules, and is
  also added to the __main__ namespace.

XXX GvR Redesign this interface (yet again) as follows:

- Present a dialog box for ``Run Module''

- Allow specify command line arguments in the dialog box

"""

import os
import re
import string
import tabnanny
import tokenize
import tkMessageBox
import PyShell

from configHandler import idleConf

IDENTCHARS = string.ascii_letters + string.digits + "_"

indent_message = """Error: Inconsistent indentation detected!

1) Your indentation is outright incorrect (easy to fix), OR

2) Your indentation mixes tabs and spaces.

To fix case 2, change all tabs to spaces by using Edit->Select All followed \
by Format->Untabify Region and specify the number of columns used by each tab.
"""

class ScriptBinding:

    menudefs = [
        ('run', [None,
                 ('Check Module', '<<check-module>>'),
                 ('Run Module', '<<run-module>>'), ]), ]

    def __init__(self, editwin):
        self.editwin = editwin
        # Provide instance variables referenced by Debugger
        # XXX This should be done differently
        self.flist = self.editwin.flist
        self.root = self.editwin.root

    def check_module_event(self, event):
        filename = self.getfilename()
        if not filename:
            return
        if not self.checksyntax(filename):
            return
        if not self.tabnanny(filename):
            return

    def tabnanny(self, filename):
        f = open(filename, 'r')
        try:
            tabnanny.process_tokens(tokenize.generate_tokens(f.readline))
        except tokenize.TokenError, msg:
            msgtxt, (lineno, start) = msg
            self.editwin.gotoline(lineno)
            self.errorbox("Tabnanny Tokenizing Error",
                          "Token Error: %s" % msgtxt)
            return False
        except tabnanny.NannyNag, nag:
            # The error messages from tabnanny are too confusing...
            self.editwin.gotoline(nag.get_lineno())
            self.errorbox("Tab/space error", indent_message)
            return False
        return True

    def checksyntax(self, filename):
        self.shell = shell = self.flist.open_shell()
        saved_stream = shell.get_warning_stream()
        shell.set_warning_stream(shell.stderr)
        f = open(filename, 'r')
        source = f.read()
        f.close()
        if '\r' in source:
            source = re.sub(r"\r\n", "\n", source)
            source = re.sub(r"\r", "\n", source)
        if source and source[-1] != '\n':
            source = source + '\n'