Merge pull request #1279 from pimutils/config_based_theming

ikhal: initial support for config based ikhal theming

CHANGELOG.rst

@@ -14,6 +14,8 @@ not released yet
 * optimization in ikhal when editing events in the far future or past
 * FIX an issue in ikhal with updating the view of the event list after editing
   an event
+* NEW properties of ikhal themes (dark and light) can now be overriden from the
+  config file (via the new [palette] section, check the documenation)
 
 0.11.2
 ======

khal/settings/khal.spec

@@ -257,7 +257,7 @@ blank_line_before_day = boolean(default=False)
 # `khal/settings/khal.spec` in the section `[default]` of the property `theme`.
 #
 # __ http://urwid.org/manual/displayattributes.html
-# .. _github: # https://github.com/pimutils/khal/issues
+# .. _github: https://github.com/pimutils/khal/issues
 theme = option('dark', 'light', default='dark')
 
 # Whether to show a visible frame (with *box drawing* characters) around some
@@ -324,3 +324,36 @@ multiple_on_overflow = boolean(default=False)
 # actually disables highlighting for events that should use the
 # default color.
 default_color = color(default='')
+
+# Override ikhal's color theme with a custom palette. This is useful to style
+# certain elements of ikhal individually.
+# Palette entries take the form of `key = foreground, background, mono,
+# foreground_high, background_high` where foreground and background are used in
+# "low color mode"  and foreground_high and background_high are used in "high
+# color mode" and mono if only monocolor is supported. If you don't want to set
+# a value for a certain color, use an empty string (`''`).
+# Valid entries for low color mode are listed on the `urwid website
+# <http://urwid.org/manual/displayattributes.html#standard-foreground-colors>`_. For
+# high color mode you can use any valid 24-bit color value, e.g. `'#ff0000'`.
+#
+# .. note::
+#     24-bit colors must be enclosed in single quotes to be parsed correctly,
+#     otherwise the `#` will be interpreted as a comment.
+#
+# Most modern terminals should support high color mode.
+#
+# Example entry (particular ugly):
+#
+# .. highlight:: ini
+#
+# ::
+#
+#  [palette]
+#  header = light red, default, default, '#ff0000', default
+#  edit = '', '', 'bold', '#FF00FF', '#12FF14'
+#  footer = '', '', '', '#121233', '#656599'
+#
+# See the default palettes in `khal/ui/colors.py` for all available keys.
+# If you can't theme an element in ikhal, please open an issue on `github
+# <https://github.com/pimutils/khal/issues/new/choose>`_.
+[palette]

khal/settings/utils.py

@@ -69,11 +69,10 @@ def is_timedelta(string: str) -> dt.timedelta:
         raise VdtValueError(f"Invalid timedelta: {string}")
 
 
-def weeknumber_option(option: str) -> Union[str, Literal[False]]:
+def weeknumber_option(option: str) -> Union[Literal['left', 'right'], Literal[False]]:
     """checks if *option* is a valid value
 
     :param option: the option the user set in the config file
-    :type option: str
     :returns: 'off', 'left', 'right' or False
     """
     option = option.lower()
@@ -89,11 +88,10 @@ def weeknumber_option(option: str) -> Union[str, Literal[False]]:
             "'off', 'left' or 'right'")
 
 
-def monthdisplay_option(option: str) -> str:
+def monthdisplay_option(option: str) -> Literal['firstday', 'firstfullweek']:
     """checks if *option* is a valid value
 
     :param option: the option the user set in the config file
-    :returns: firstday, firstfullweek
     """
     option = option.lower()
     if option == 'firstday':
@@ -215,6 +213,17 @@ def get_vdir_type(_: str) -> str:
     # TODO implement
     return 'calendar'
 
+def validate_palette_entry(attr, definition: str) -> bool:
+    if len(definition) not in (2, 3, 5):
+        logging.error('Invalid color definition for %s: %s, must be of length, 2, 3, or 5',
+                      attr, definition)
+        return False
+    if (definition[0] not in COLORS and definition[0] != '') or \
+            (definition[1] not in COLORS and definition[1] != ''):
+        logging.error('Invalid color definition for %s: %s, must be one of %s',
+                      attr, definition, COLORS.keys())
+        return False
+    return True
 
 def config_checks(
     config,
@@ -263,3 +272,11 @@ def config_checks(
         if config['calendars'][calendar]['color'] == 'auto':
             config['calendars'][calendar]['color'] = \
                 _get_color_from_vdir(config['calendars'][calendar]['path'])
+
+    # check palette settings
+    valid_palette = True
+    for attr in config.get('palette', []):
+        valid_palette = valid_palette and validate_palette_entry(attr, config['palette'][attr])
+    if not valid_palette:
+        logger.fatal('Invalid palette entry')
+        raise InvalidSettingsError()