Adds email categories and user preferences for them

Pipfile

@@ -43,6 +43,7 @@ nordigen = "*"
 openpyxl = "*"
 phonenumbers = "*"
 setuptools = "*"
+django-modeltranslation = "*"
 
 [requires]
 python_version = "3.11"

drfx/settings.py

@@ -73,6 +73,8 @@
 
 # Application definition
 INSTALLED_APPS = [
+    # field translations for models
+    "modeltranslation",
     "django.contrib.admin",
     "django.contrib.auth",
     "django.contrib.contenttypes",

emails/admin.py

@@ -5,15 +5,177 @@
 from django.urls import path, reverse
 from django.utils.html import format_html
 from django.utils.translation import gettext_lazy as _
+from django.forms import ModelForm
+from modeltranslation.admin import TranslationAdmin
 
 from .forms import EmailActionForm
-from .models import Email
+from .models import Email, EmailCategory, EmailPreference
 
+@admin.register(EmailCategory)
+class EmailCategoryAdmin(TranslationAdmin):
+    list_display = (
+        'display_name',
+        'name',
+        'is_static',
+        'user_configurable',
+        'default_enabled',
+        'sort_priority',
+        'subscriber_count',
+        'created'
+    )
+    list_filter = ('is_static', 'user_configurable', 'default_enabled', 'created')
+    search_fields = ('name', 'display_name', 'description')
+    list_editable = ('sort_priority',)
+    readonly_fields = ('created', 'updated', 'subscriber_stats', 'subscriber_count', 'is_static')
+
+    fieldsets = (
+        (None, {
+            'fields': ('name', 'display_name', 'description')
+        }),
+        (_('Settings'), {
+            'fields': ('user_configurable', 'default_enabled', 'sort_priority')
+        }),
+        (_('System'), {
+            'fields': ('is_static',),
+            'classes': ('collapse',)
+        }),
+        (_('Metadata'), {
+            'fields': ('created', 'updated', 'subscriber_stats'),
+            'classes': ('collapse',)
+        })
+    )
+
+    def subscriber_count(self, obj):
+        """Show how many users are subscribed to this category."""
+        count = obj.preferences.filter(enabled=True).count()
+        total = obj.preferences.count()
+        return f"{count} / {total}"
+    subscriber_count.short_description = _("Subscribers")
+
+    def subscriber_stats(self, obj):
+        """Detailed subscriber statistisc"""
+        if not obj.pk:
+            return "-"
+
+        enabled = obj.preferences.filter(enabled=True).count()
+        disabled = obj.preferences.filter(enabled=False).count()
+        from users.models import CustomUser
+        total_users = CustomUser.objects.filter(is_active=True).count()
+        no_preference = total_users - (enabled + disabled)
+
+        return format_html(
+            "<strong>Enabled:</strong> {} | <strong>Disabled:</strong> {} | <strong>No preference set:</strong> {}",
+            enabled, disabled, no_preference
+        )
+    subscriber_stats.short_description = _("Detailed Statistics")
+
+    def get_readonly_fields(self, request, obj=None):
+        """
+        Make static categories' critical fields read only
+        """
+        readonly = list(super().get_readonly_fields(request, obj))
+
+        if obj and obj.is_static:
+            readonly.extend(['name', 'user_configurable'])
+        return readonly
+
+    def has_delete_permission(self, request, obj = None):
+        """
+        Prevent deletion of static categories
+        """
+        if obj and obj.is_static:
+            return False
+        return super().has_delete_permission(request, obj)
+
+
+@admin.register(EmailPreference)
+class EmailPreferenceAdmin(admin.ModelAdmin):
+    list_display = ('user', 'category', 'enabled', 'updated')
+    list_filter = ('enabled', 'category', 'updated')
+    search_fields = ('user__email', 'user__first_name', 'user__last_name')
+    raw_id_fields = ('user',)
+
+    def has_add_permission(self, request):
+        return False
+
+# This is apparently the only way to add help text to method-defined fields /__\
+class EmailAdminForm(ModelForm):
+    class Meta:
+        model = Email
+        help_texts = {'recipient_preview': _("Estimated based on current user preferences and active users. Save the email to update this.")}
+        exclude = ()
 
 class EmailAdmin(admin.ModelAdmin):
-    list_display = ("subject", "sent", "email_actions")
-    list_filter = ("sent",)
-    readonly_fields = ("slug", "created", "last_modified", "sent", "email_actions")
+    form = EmailAdminForm
+
+    list_display = ("subject", "category", "sent", "recipients_count", "email_actions")
+    list_filter = ("sent", "category")
+    readonly_fields = ("slug", "created", "last_modified", "sent", "recipients_count", "email_actions", "recipient_preview")
+
+    fieldsets = (
+        (None, {
+            'fields': ('subject', 'category', 'content')
+        }),
+        (_("Metadata"), {
+            'fields': ('slug', 'created', 'last_modified', 'sent'),
+        }),
+        (_("Recipients"), {
+            'fields': ('recipient_preview', ),
+        })
+    )
+
+    def recipient_preview(self, obj):
+        """Show how many users will receive this email based on category."""
+        if not obj.pk or obj.sent:
+            return "-"
+
+        from users.models import CustomUser
+        all_active_users = CustomUser.objects.filter(is_active=True)
+
+        if not obj.category:
+            return format_html(
+                "<strong>All active users:</strong> {}",
+                all_active_users.count()
+            )
+
+        if not obj.category.user_configurable:
+            return format_html(
+                "<strong>All active users:</strong> {} (Category is not user-configurable)",
+                all_active_users.count()
+            )
+
+        #Count users who haven't opted out
+        opted_out = EmailPreference.objects.filter(
+            category=obj.category,
+            enabled=False,
+            user__is_active=True
+        ).count()
+        total = all_active_users.count()
+        will_receive = total - opted_out
+
+        return format_html(
+            "<strong>Will receive:</strong> {} | <strong>Opted out:</strong> {} | <strong>Total active:</strong> {}",
+            will_receive, opted_out, total
+        )
+    recipient_preview.short_description = _("Recipient preview")
+
+    def get_fieldsets(self, request, obj = None):
+        """
+        Show recipient preview for unsent mails, actual recipients for sent mails
+        """
+        base = list(super().get_fieldsets(request, obj))
+
+        for idx, (title, options) in enumerate(base):
+            if title == _("Recipients") or title == "Recipients":
+                if getattr(obj, 'sent', None):
+                    fields = ('recipients_count',)
+                else:
+                    fields = ('recipient_preview',)
+                new_options = dict(options)
+                new_options['fields'] = fields
+                base[idx] = (title, new_options)
+                break
+        return tuple(base)
 
     def get_urls(self):
         """
@@ -35,17 +197,15 @@ def email_actions(self, obj):
         """
         if obj.sent:
             return format_html(
-                '<a class="button" target="_blank" href="{url}">{text}</a>'.format(
+                '<a class="button" target="_blank" href="{url}">{text}</a>',
                     url=reverse("email", args=[obj.created.strftime("%s"), obj.slug]),
-                    text=_("Show browser version"),
-                )
+                    text=_("Show browser version")
             )
         if obj.id:
             return format_html(
-                '<a class="button" href="{url}">{text}</a>'.format(
+                '<a class="button" href="{url}">{text}</a>',
                     url=reverse("admin:email-send", args=[obj.pk]),
-                    text=_("Send now"),
-                )
+                    text=_("Send now")
             )
 
     def send_email(self, request, *args, **kwargs):
@@ -84,6 +244,14 @@ def send_email(self, request, *args, **kwargs):
         context["email"] = email
         context["title"] = _("Send email")
 
+        category_name = None
+        category_is_configurable = False
+        if getattr(email, "category", None):
+            category_name = email.category.display_name
+            category_is_configurable = email.category.user_configurable
+        context["category_name"] = category_name
+        context["category_is_configurable"] = category_is_configurable
+
         return TemplateResponse(
             request,
             "admin/send-email.html",

emails/apps.py

@@ -3,3 +3,6 @@
 
 class EmailsConfig(AppConfig):
     name = "emails"
+
+    def ready(self):
+        import emails.signals