Implement flags for CLI script.

-c, -d and -t are supported to specify alternative configuration files,
archive files or todo.txt files respectively.

The configuration file specified with -c has the highest priority.

The files specified with -d or -t are always used regardless of the
configuration.

topydo/cli/Main.py

@@ -16,26 +16,21 @@
 
 """ Entry file for the Python todo.txt CLI. """
 
+import getopt
 import sys
 
 def usage():
     """ Prints the usage of the todo.txt CLI """
-    exit(1)
 
-def arguments(p_start=2):
-    """
-    Retrieves all values from the argument list starting from the given
-    position.
+    print """\
+-c : Specify an alternative configuration file.
+-d : Specify an alternative archive file (done.txt)
+-h : This help text
+-t : Specify an alternative todo file
+-v : Print version and exit
+"""
 
-    This is a parameter, because argv has a different structure when no
-    subcommand was given and it fallbacks to the default subcommand.
-    """
-    try:
-        values = sys.argv[p_start:]
-    except IndexError:
-        usage()
-
-    return values
+    exit(0)
 
 def write(p_file, p_string):
     """
@@ -54,6 +49,13 @@ def error(p_string):
 
     write(sys.stderr, p_string)
 
+def version():
+    """ Print the current version and exit. """
+    from topydo.lib.Version import VERSION, LICENSE
+    print "topydo %s\n" % (VERSION)
+    print LICENSE
+    exit(0)
+
 from topydo.lib.Config import config, ConfigError
 
 # First thing is to poke the configuration and check whether it's sane
@@ -88,6 +90,38 @@ class CLIApplication(object):
     def __init__(self):
         self.todolist = TodoList.TodoList([])
 
+        self.config = config()
+        self.path = self.config.todotxt()
+        self.archive_path = self.config.archive()
+
+    def _process_flags(self):
+        try:
+            opts, args = getopt.getopt(sys.argv[1:], "c:d:ht:v")
+        except getopt.GetoptError as e:
+            error(str(e))
+            exit(1)
+
+        alt_path = None
+        alt_archive = None
+
+        for opt, value in opts:
+            if opt == "-c":
+                self.config = config(value)
+            elif opt == "-t":
+                alt_path = value
+            elif opt == "-d":
+                alt_archive = value
+            elif opt == "-v":
+                version()
+            else:
+                usage()
+
+        self.path = alt_path if alt_path else self.config.todotxt()
+        self.archive_path = alt_archive \
+            if alt_archive else self.config.archive()
+
+        return args
+
     def archive(self):
         """
         Performs an archive action on the todolist.
@@ -95,7 +129,7 @@ class CLIApplication(object):
         This means that all completed tasks are moved to the archive file
         (defaults to done.txt).
         """
-        archive_file = TodoFile.TodoFile(config().archive())
+        archive_file = TodoFile.TodoFile(self.archive_path)
         archive = TodoList.TodoList(archive_file.read())
 
         if archive:
@@ -107,13 +141,15 @@ class CLIApplication(object):
 
     def run(self):
         """ Main entry function. """
-        todofile = TodoFile.TodoFile(config().todotxt())
+        args = self._process_flags()
+
+        todofile = TodoFile.TodoFile(self.path)
         self.todolist = TodoList.TodoList(todofile.read())
 
         try:
-            subcommand = sys.argv[1]
+            subcommand = args.pop(0)
         except IndexError:
-            subcommand = config().default_command()
+            subcommand = self.config.default_command()
 
         subcommand_map = {
           'add': AddCommand,
@@ -139,10 +175,8 @@ class CLIApplication(object):
           'tag': TagCommand,
         }
 
-        args = arguments()
         if not subcommand in subcommand_map:
-            subcommand = config().default_command()
-            args = arguments(1)
+            subcommand = self.config.default_command()
 
         command = subcommand_map[subcommand](args, self.todolist,
             lambda o: write(sys.stdout, o),

topydo/lib/Version.py

+""" Version of Topydo. """
+
+VERSION = 0.1
+
+LICENSE = """Copyright (C) 2014 Bram Schoenmakers
+License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law."""