Wash list of theme names

Make themes list depend on installed themes, not themes in settings. If
they are out of sync it will be reported on startup with a chcek, and
logged.

README.rst

@@ -242,7 +242,10 @@ How to customize the look:
     * `list of daisyUI color names`_
     * `Tailwind CSS theme customization`_
 
-*  Override the default main stylesheet path by providing a ``path_to_stylesheet`` value in a template ``context``.
+*  Override the default main stylesheet path by setting
+  ``ARGUS_STYLESHEET_PATH`` in the environment. The path is under
+  ``STATIC_URL``. This depends on the context processor
+  ``argus_htmx.context_processors.path_to_stylesheet``.
 *  Include additional styles/stylesheets using the ``head`` block in your templates.
 *  Generate a Tailwind config file by running the ``tailwind_config`` management
    command. By default the generated file will be based on

src/argus_htmx/appconfig.py

@@ -25,6 +25,7 @@
         },
         "context_processors": [
             "argus.auth.context_processors.preferences",
+            "argus_htmx.context_processors.path_to_stylesheet",
         ],
         "middleware": {
             "argus_htmx.middleware.LoginRequiredMiddleware": "end",

src/argus_htmx/apps.py

@@ -1,4 +1,5 @@
 import pathlib
+
 from django.apps import AppConfig
 
 
@@ -9,3 +10,7 @@ class HtmxFrontendConfig(AppConfig):
 
     def tailwind_css_files(self):
         yield from pathlib.Path(__file__).parent.glob("tailwindtheme/snippets/*.css")
+
+    def ready(self):
+        # Register checks
+        from .checks import check_for_valid_themes_list  # noqa: F401

src/argus_htmx/checks.py

@@ -0,0 +1,29 @@
+from django.core.checks import Error, Warning, register
+from django.core.exceptions import ImproperlyConfigured
+
+from .themes.utils import get_theme_names, get_stylesheet_path
+
+
+@register
+def check_for_valid_themes_list(app_configs, **kwargs):
+    styles_path = get_stylesheet_path()
+    themes = []
+    try:
+        themes = get_theme_names(quiet=False)
+    except ImproperlyConfigured as e:
+        return [
+            Warning(
+                str(e),
+                hint=f"Regenerate {styles_path}",
+                id="argus_htmx.T001",
+            )
+        ]
+    if not themes:
+        return [
+            Error(
+                "no themes installed",
+                hint=f'Check the settings "DAISYUI_THEMES" and "TAILWIND_THEME_OVERRIDE" and regenerate {styles_path}',
+                id="argus_htmx.T002",
+            )
+        ]
+    return []

src/argus_htmx/context_processors.py

@@ -7,12 +7,8 @@
 See django settings for ``TEMPLATES``.
 """
 
-from argus.auth.models import Preferences
+from .settings import STYLESHEET_PATH
 
 
-def preferences(request):
-    pref_sets = Preferences.objects.filter(user=request.user)
-    prefdict = {}
-    for pref_set in pref_sets:
-        prefdict[pref_set._namespace] = pref_set.get_context()
-    return {"preferences": prefdict}
+def path_to_stylesheet(request):
+    return {"path_to_stylesheet": STYLESHEET_PATH}

src/argus_htmx/management/commands/tailwind_config.py

@@ -8,7 +8,7 @@
 from django.template.context import make_context
 from django.template.loader import get_template
 
-from argus_htmx.themes.utils import get_themes
+from argus_htmx.themes.utils import get_raw_themes_setting
 from argus_htmx import settings as argus_htmx_settings
 
 
@@ -78,7 +78,7 @@ def get_context(self, target_dir: pathlib.Path):
                 argus_htmx_settings.TAILWIND_THEME_OVERRIDE,
             ),
             "daisyuithemes": textwrap.indent(
-                json.dumps(get_themes(), indent=2),
+                json.dumps(get_raw_themes_setting(), indent=2),
                 prefix=10 * " ",
                 predicate=lambda line: line != "[\n",  # this is kinda hacky, but eh
             ),

src/argus_htmx/settings.py

@@ -25,6 +25,7 @@
 TAILWIND_CONFIG_TARGET = "src/argus_htmx/tailwindtheme/tailwind.config.js"
 TAILWIND_CSS_TARGET = "src/argus_htmx/tailwindtheme/styles.css"
 
+STYLESHEET_PATH_DEFAULT = "styles.css"
 DEFAULT_THEMES = [
     "dark",
     "light",
@@ -57,3 +58,4 @@
 THEME_DEFAULT = get_str_env("ARGUS_THEME_DEFAULT", "argus")
 DEFAULT_THEME_OVERRIDE = {}
 TAILWIND_THEME_OVERRIDE = get_json_env("TAILWIND_THEME_OVERRIDE", DEFAULT_THEME_OVERRIDE, quiet=True)
+STYLESHEET_PATH = get_str_env("ARGUS_STYLESHEET_PATH", STYLESHEET_PATH_DEFAULT)

src/argus_htmx/themes/utils.py

@@ -1,21 +1,68 @@
+import logging
+from pathlib import Path
+from re import findall
+
 from django.conf import settings
-from argus_htmx import settings as argus_htmx_settings
+from django.core.exceptions import ImproperlyConfigured
+from django.contrib.staticfiles.finders import find
+
+from argus_htmx import settings as fallbacks
+
+
+__all__ = [
+    "get_raw_themes_setting",
+    "get_theme_names",
+    "get_theme_default",
+]
+
 
+LOG = logging.getLogger(__name__)
 
-def get_themes():
-    return getattr(settings, "DAISYUI_THEMES", argus_htmx_settings.DAISYUI_THEMES)
 
+def get_raw_themes_setting():
+    return getattr(settings, "DAISYUI_THEMES", fallbacks.DAISYUI_THEMES)
 
-def get_theme_names():
-    themes = get_themes()
+
+def get_themes_from_setting():
+    themes_setting = get_raw_themes_setting()
     theme_names = []
-    for theme in themes:
+    for theme in themes_setting:
         if isinstance(theme, str):
             theme_names.append(theme)
         elif isinstance(theme, dict):
             theme_names.extend(theme.keys())
     return theme_names
 
 
+def get_stylesheet_path():
+    return getattr(settings, "STYLESHEET_PATH", fallbacks.STYLESHEET_PATH)
+
+
+def get_themes_from_css():
+    THEME_NAME_RE = "(?P<theme>[-_\w]+)"
+    DATA_THEME_RE = f"\[data-theme={THEME_NAME_RE}\]"
+
+    absolute_stylesheet_path = Path(find(get_stylesheet_path()))
+    styles_css = absolute_stylesheet_path.read_text()
+
+    return findall(DATA_THEME_RE, styles_css)
+
+
+def get_theme_names(quiet=True):
+    ERROR_MSG = "Themes in settings are out of sync with themes installed"
+
+    themes_from_setting = set(get_themes_from_setting())
+    themes_from_css = set(get_themes_from_css())
+    installed_themes = themes_from_setting & themes_from_css
+
+    all_themes = themes_from_setting | themes_from_css
+    if all_themes != installed_themes:
+        LOG.warning(ERROR_MSG)
+        if not quiet:
+            raise ImproperlyConfigured(ERROR_MSG)
+
+    return installed_themes
+
+
 def get_theme_default():
-    return getattr(settings, "THEME_DEFAULT", argus_htmx_settings.THEME_DEFAULT)
+    return getattr(settings, "THEME_DEFAULT", fallbacks.THEME_DEFAULT)