gramps/gramps/cli/user.py

#
# Gramps - a GTK+/GNOME based genealogy program
#
# Copyright (C) 2010  Brian G. Matherly
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# $Id$
#

"""
The User class provides basic interaction with the user.
"""

#------------------------------------------------------------------------
#
# Python Modules
#
#------------------------------------------------------------------------
from __future__ import print_function

import sys

#------------------------------------------------------------------------
#
# Gramps Modules
#
#------------------------------------------------------------------------
from gramps.gen.ggettext import gettext as _
from gramps.gen.user import User

#------------------------------------------------------------------------
#
# Private Constants
#
#------------------------------------------------------------------------
_SPINNER = ['|', '/', '-', '\\']

#-------------------------------------------------------------------------
#
# User class
#
#-------------------------------------------------------------------------
class User(User):
    """
    This class provides a means to interact with the user via CLI.
    It implements the interface in gramps.gen.user.User()
    """
    def __init__(self, callback=None, error=None):
        self.steps = 0;
        self.current_step = 0;
        self.callback_function = callback
        self.error_function = error
    
    def begin_progress(self, title, message, steps):
        """
        Start showing a progress indicator to the user.
        
        @param title: the title of the progress meter
        @type title: str
        @param message: the message associated with the progress meter
        @type message: str
        @param steps: the total number of steps for the progress meter.
            a value of 0 indicates that the ending is unknown and the
            meter should just show activity.
        @type steps: int
        @returns: none
        """
        print(message)
        self.steps = steps
        self.current_step = 0;
        if self.steps == 0:
            sys.stdout.write(_SPINNER[self.current_step])
        else:
            sys.stdout.write("00%")
    
    def step_progress(self):
        """
        Advance the progress meter.
        """
        self.current_step += 1
        if self.steps == 0:
            self.current_step %= 4
            sys.stdout.write("\r  %s  " % _SPINNER[self.current_step])
        else:
            percent = int((float(self.current_step) / self.steps) * 100)
            sys.stdout.write("\r%02d%%" % percent)

    def callback(self, percentage, text=None):
        """
        Display the precentage.
        """
        if self.callback_function:
            if text:
                self.callback_function(percentage, text)
            else:
                self.callback_function(percentage)
        else:
            if text is None:
                sys.stdout.write("\r%02d%%" % percentage)
            else:
                sys.stdout.write("\r%02d%% %s" % (percentage, text))

    def end_progress(self):
        """
        Stop showing the progress indicator to the user.
        """
        sys.stdout.write("\r100%\n")
    
    def prompt(self, title, question):
        """
        Ask the user a question. The answer must be "yes" or "no".
        The user will be forced to answer the question before proceeding.
        
        @param title: the title of the question
        @type title: str
        @param question: the question
        @type question: str
        @returns: the user's answer to the question
        @rtype: bool
        """
        return False
    
    def warn(self, title, warning=""):
        """
        Warn the user.
        
        @param title: the title of the warning
        @type title: str
        @param warning: the warning
        @type warning: str
        @returns: none
        """
        print("%s %s" % (title, warning))
    
    def notify_error(self, title, error=""):
        """
        Notify the user of an error.
        
        @param title: the title of the error
        @type title: str
        @param error: the error message
        @type error: str
        @returns: none
        """
        if self.error_function:
            self.error_function(title, error)
        else:
            print("%s %s" % (title, error))

    def notify_db_error(self, error):
        """
        Notify the user of a DB error.
        
        @param error: the error message
        @type error: str
        @returns: none
        """
        self.notify_error(
            _("Low level database corruption detected"),
            _("Gramps has detected a problem in the underlying "
              "Berkeley database. This can be repaired from "
              "the Family Tree Manager. Select the database and "
              'click on the Repair button') + '\n\n' + error)

    def info(self, msg1, infotext, parent=None, monospaced=False):
        """
        Displays information to the CLI
        """
        print(msg1)
        print(infotext)