Improved installation script.

install.py

@@ -5,6 +5,18 @@
 
 from os import path
 
+EMACS_CONF_FILE = 'emacs'
+EMACS_CONF_DIR = 'emacs.d'
+
+def hidden_name(name):
+    return '.%s' % name
+
+def unhidden_name(name):
+    if name.startswith('.'):
+        return name[1:]
+    else:
+        return name
+
 def is_windows():
     return os.name == 'nt'
 
@@ -15,11 +27,16 @@ def home_path():
     return windows_home() if is_windows() else os.environ['HOME']
 
 def find_base():
-    if path.isfile('emacs'):
+    if path.isfile(EMACS_CONF_FILE):
         return os.curdir
     else:
         # here add better diagnostic
-        raise RuntimeError("Can't find configuration files.")
+        enclosing_dir = path.dirname(__file__)
+        tentative_emacs = path.join(enclosing_dir, EMACS_CONF_FILE)
+        if path.isfile(tentative_emacs):
+            return enclosing_dir
+        else:
+            raise RuntimeError("Can't find configuration files.")
 
 # everybody nows that explicit logging this way sucks
 def overwrite_if_more_recent(command, src, dest, *args, **kw):
@@ -39,13 +56,45 @@ def overwrite_if_more_recent(command, src, dest, *args, **kw):
             command(src, dest, *args, **kw)
             print '%(src)s -> %(dest)s' % locals()
 
-HOME = home_path()
-BASE_DIR = find_base()
-overwrite_if_more_recent(shutil.copyfile, 'emacs', path.join(HOME, '.emacs'))
-overwrite_if_more_recent(
-    shutil.copytree, 'emacs.d',
-    path.join(HOME, '.emacs.d'),
-    ignore=shutil.ignore_patterns('*~', '*.elc')
-)
+if __name__ == '__main__':
+    HOME_DIR = home_path()
+    BASE_DIR = find_base()
+
+    EMACS_VERSIONED_FILE = path.join(BASE_DIR, unhidden_name(EMACS_CONF_FILE))
+    EMACS_VERSIONED_DIR = path.join(BASE_DIR, unhidden_name(EMACS_CONF_DIR))
+
+    EMACS_ACTIVE_FILE = path.join(HOME_DIR, hidden_name(EMACS_CONF_FILE))
+    EMACS_ACTIVE_DIR = path.join(HOME_DIR, hidden_name(EMACS_CONF_DIR))
+
+    try:
+        command = sys.argv[1]
+    except KeyError:
+        command = 'activate'
+
+    if command == 'activate':
+        overwrite_if_more_recent(
+            shutil.copyfile,
+            EMACS_VERSIONED_FILE,
+            EMACS_ACTIVE_FILE
+        )
+        overwrite_if_more_recent(
+            shutil.copytree,
+            EMACS_VERSIONED_DIR,
+            EMACS_ACTIVE_DIR,
+            ignore=shutil.ignore_patterns('*~', '*.elc')
+        )
+    elif 'store':
+        overwrite_if_more_recent(
+            shutil.copyfile,
+            EMACS_ACTIVE_FILE,
+            EMACS_VERSIONED_FILE
+        )
+        overwrite_if_more_recent(
+            shutil.copytree,
+            EMACS_ACTIVE_DIR,
+            EMACS_VERSIONED_DIR,
+            ignore=shutil.ignore_patterns('*~', '*.elc')
+        )
+