Fixing a few edge cases

rtv/page.py

@@ -11,7 +11,6 @@ import six
 from kitchen.text.display import textual_width
 
 from . import docs
-from .theme import get_next_theme, get_previous_theme
 from .objects import Controller, Command
 from .clipboard import copy
 from .exceptions import TemporaryFileError, ProgramError
@@ -98,7 +97,11 @@ class Page(object):
 
     @PageController.register(Command('PREVIOUS_THEME'))
     def previous_theme(self):
-        theme = get_previous_theme(self.term.theme)
+
+        theme = self.term.theme_list.previous(self.term.theme)
+        while not self.term.test_theme(theme):
+            theme = self.term.theme_list.previous(theme)
+
         self.term.set_theme(theme)
         self.draw()
         message = self.term.theme.display_string
@@ -106,7 +109,11 @@ class Page(object):
 
     @PageController.register(Command('NEXT_THEME'))
     def next_theme(self):
-        theme = get_next_theme(self.term.theme)
+
+        theme = self.term.theme_list.next(self.term.theme)
+        while not self.term.test_theme(theme):
+            theme = self.term.theme_list.next(theme)
+
         self.term.set_theme(theme)
         self.draw()
         message = self.term.theme.display_string

rtv/terminal.py

@@ -21,7 +21,7 @@ import six
 from kitchen.text.display import textual_width_chop
 
 from . import exceptions, mime_parsers
-from .theme import Theme
+from .theme import Theme, ThemeList
 from .objects import LoadScreen
 
 try:
@@ -57,6 +57,7 @@ class Terminal(object):
         self.config = config
         self.loader = LoadScreen(self)
         self.theme = None  # Initialized by term.set_theme()
+        self.theme_list = ThemeList()
 
         self._display = None
         self._mailcap_dict = mailcap.getcaps()
@@ -829,6 +830,20 @@ class Terminal(object):
 
         return self.theme.get(element)
 
+    @staticmethod
+    def test_theme(theme):
+        """
+        Check if the given theme is supported by the terminal
+        """
+        terminal_colors = curses.COLORS if curses.has_colors() else 0
+
+        if theme.required_colors > terminal_colors:
+            return False
+        elif theme.required_color_pairs > curses.COLOR_PAIRS:
+            return False
+        else:
+            return True
+
     def set_theme(self, theme=None):
         """
         Check that the terminal supports the provided theme, and applies
@@ -839,10 +854,7 @@ class Terminal(object):
         should be compatible with any terminal that supports basic colors.
         """
 
-        if curses.has_colors():
+        terminal_colors = curses.COLORS if curses.has_colors() else 0
-            terminal_colors = curses.COLORS
-        else:
-            terminal_colors = 0
 
         if theme is None:
             theme = Theme(use_color=bool(terminal_colors))

rtv/theme.py

@@ -50,8 +50,6 @@ class Theme(object):
     for i in range(256):
         COLOR_CODES['ansi_{0}'.format(i)] = i
 
-    # TODO: Apply selected on top of items, not underneath them
-
     # For compatibility with as many terminals as possible, the default theme
     # can only use the 8 basic colors with the default color as the background
     DEFAULT_THEME = {
@@ -159,26 +157,28 @@ class Theme(object):
                 elements[key] = (None, None, None)
 
         self._set_fallback(elements, 'Normal', (-1, -1, curses.A_NORMAL))
-        self._set_fallback(elements, 'Selected', 'Normal')
-        self._set_fallback(elements, 'SelectedCursor', 'Normal')
 
-        # Most elements have two possible attribute states:
+        # Fill in the ``None`` values for all of the elements with normal text
-        #   1. The default state - inherits from "Normal"
-        #   2. The selected state - inherits from "Selected" and is
-        #      prefixed by the "@" sign.
         for name in self.DEFAULT_THEME['normal']:
-            dest = '@{0}'.format(name)
-            self._set_fallback(elements, name, 'Selected', dest)
             self._set_fallback(elements, name, 'Normal')
-
         for name in self.DEFAULT_THEME['cursor']:
-            dest = '@{0}'.format(name)
-            self._set_fallback(elements, name, 'SelectedCursor', dest)
             self._set_fallback(elements, name, 'Normal')
-
         for name in self.DEFAULT_THEME['page']:
             self._set_fallback(elements, name, 'Normal')
 
+        # Create the "Selected" versions of elements, which are prefixed with
+        # the @ symbol. For example, "@CommentText" represents how comment
+        # text is formatted when it is highlighted by the cursor.
+        for name in self.DEFAULT_THEME['normal']:
+            dest = '@{0}'.format(name)
+            self._set_fallback(elements, 'Selected', name, dest)
+        for name in self.DEFAULT_THEME['cursor']:
+            dest = '@{0}'.format(name)
+            self._set_fallback(elements, 'SelectedCursor', name, dest)
+
+        self._set_fallback(elements, 'Selected', 'Normal')
+        self._set_fallback(elements, 'SelectedCursor', 'Normal')
+
         self.elements = elements
 
         if self.use_color:
@@ -546,8 +546,3 @@ class ThemeList(object):
 
     def previous(self, theme):
         return self._step(theme, -1)
-
-
-theme_list = ThemeList()
-get_next_theme = theme_list.next
-get_previous_theme = theme_list.previous

rtv/themes/high_contrast.cfg

@@ -1,50 +0,0 @@
-[theme]
-;<element>            = <foreground>  <background>  <attributes>
-Normal                = default       default       -
-Selected              = -             -             -
-SelectedCursor        = -             -             reverse
-
-TitleBar              = cyan          -             bold+reverse
-OrderBar              = yellow        -             bold
-OrderBarHighlight     = yellow        -             bold+reverse
-HelpBar               = cyan          -             bold+reverse
-Prompt                = cyan          -             bold+reverse
-NoticeInfo            = -             -             bold
-NoticeLoading         = -             -             bold
-NoticeError           = -             -             bold
-NoticeSuccess         = -             -             bold
-
-CursorBlock           = -             -             -
-CursorBar1            = magenta       -             -
-CursorBar2            = cyan          -             -
-CursorBar3            = green         -             -
-CursorBar4            = yellow        -             -
-
-CommentAuthor         = cyan          -             bold
-CommentAuthorSelf     = green         -             bold
-CommentCount          = -             -             -
-CommentText           = -             -             -
-Created               = -             -             -
-Downvote              = red           -             bold
-Gold                  = yellow        -             bold
-HiddenCommentExpand   = -             -             bold
-HiddenCommentText     = -             -             -
-MultiredditName       = yellow        -             bold
-MultiredditText       = -             -             -
-NeutralVote           = -             -             bold
-NSFW                  = red           -             bold+reverse
-Saved                 = green         -             -
-Score                 = -             -             -
-Separator             = -             -             bold
-Stickied              = green         -             -
-SubscriptionName      = yellow        -             bold
-SubscriptionText      = -             -             -
-SubmissionAuthor      = green         -             bold
-SubmissionFlair       = red           -             -
-SubmissionSubreddit   = yellow        -             -
-SubmissionText        = -             -             -
-SubmissionTitle       = -             -             bold
-Upvote                = green         -             bold
-Link                  = cyan          -             underline
-LinkSeen              = magenta       -             underline
-UserFlair             = yellow        -             bold

scripts/demo_theme.py

@@ -15,7 +15,7 @@ from collections import Counter
 from vcr import VCR
 from six.moves.urllib.parse import urlparse, parse_qs
 
-from rtv.theme import Theme, get_next_theme, get_previous_theme, theme_list
+from rtv.theme import Theme, ThemeList
 from rtv.config import Config
 from rtv.packages import praw
 from rtv.oauth import OAuthHelper
@@ -244,6 +244,8 @@ def main():
         oauth = OAuthHelper(reddit, term, config)
         oauth.authorize()
 
+        theme_list = ThemeList()
+
         while True:
             term = Terminal(stdscr, config)
             term.set_theme(theme)
@@ -266,14 +268,15 @@ def main():
             theme_list.reload()
 
             if ch == curses.KEY_RIGHT:
-                theme = get_next_theme(theme)
+                theme = theme_list.next(theme)
             elif ch == curses.KEY_LEFT:
-                theme = get_previous_theme(theme)
+                theme = theme_list.previous(theme)
             elif ch == Terminal.ESCAPE:
                 break
             else:
                 # Force the theme to reload
-                theme = get_next_theme(theme)
+                theme = theme_list.next(theme)
-                theme = get_previous_theme(theme)
+                theme = theme_list.previous(theme)
 
 sys.exit(main())
+