Only allow each slide to be advanced by next/previous once per auto_a…

…dvance_duration

This keeps slides from being advanced erratically when multiple displays are displaying the same auto-advancing slide deck.

OpenShow/slides/migrations/0020_display_previous_slide_display_slide_changed_at.py

@@ -0,0 +1,30 @@
+# Generated by Django 4.2.6 on 2024-04-17 09:32
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("slides", "0019_alter_display_current_slide"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="display",
+            name="previous_slide",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name="+",
+                to="slides.slide",
+            ),
+        ),
+        migrations.AddField(
+            model_name="display",
+            name="slide_changed_at",
+            field=models.DateTimeField(auto_now=True),
+        ),
+    ]

OpenShow/slides/models.py

@@ -20,6 +20,7 @@ class Display(models.Model):  # A set of characteristics used to modify slide ap
     pixel_width = models.IntegerField(default=1920)
     pixel_height = models.IntegerField(default=1080)
     custom_css = models.TextField(null=True, blank=True)
+    slide_changed_at = models.DateTimeField(auto_now=True)
     current_show = models.ForeignKey(
         to='Show',
         null=True,
@@ -32,6 +33,13 @@ class Display(models.Model):  # A set of characteristics used to modify slide ap
         blank=True,
         on_delete=models.SET_NULL,
     )
+    previous_slide = models.ForeignKey(
+        to='Slide',
+        null=True,
+        blank=True,
+        on_delete=models.SET_NULL,
+        related_name='+'
+    )
     current_theme = models.ForeignKey(
         to='Theme',
         null=True,
@@ -339,6 +347,7 @@ def send_to_display(self, displays:Iterable, show) -> None:
         """
         for display in displays:
             slide_theme = self.get_theme()
+            display.previous_slide = display.current_slide  # do the slide shuffle
             display.current_slide = self
             display.current_show = show
             if display.current_theme != slide_theme:

OpenShow/slides/views.py

@@ -1,4 +1,7 @@
+from datetime import timedelta
+
 from django.shortcuts import render, get_object_or_404, HttpResponseRedirect, reverse
+from django.utils import timezone
 from django.views.generic import DetailView, FormView, ListView, UpdateView
 from django.utils.decorators import method_decorator
 from django.views.decorators.clickjacking import xframe_options_sameorigin
@@ -13,6 +16,7 @@
 from django_eventstream import send_event
 from django.shortcuts import HttpResponse
 
+
 # This approach doesn't work well due to many extra characters being inserted into the HTML/CSS.
 # def send_slide_to_display(request, slide, display):
 #     slide_template = loader.get_template('slides/slide.html')
@@ -74,6 +78,14 @@ def form_valid(self, form):
         show = Show.objects.get(pk=form.cleaned_data['show_pk'])
         if form.cleaned_data['direction']:
             display = show.displays.all().first()
+            if display.previous_slide and display.current_slide.auto_advance:
+                if timezone.now() - \
+                        display.slide_changed_at < \
+                        timedelta(seconds=display.previous_slide.auto_advance_duration):
+                    # Abort and continue silently if we're getting a "next slide" directive and
+                    # the previous slide's auto_advance_duration has not passed
+                    # Manually selecting a different slide will override this.
+                    return HttpResponseRedirect(reverse('show', kwargs={'pk': show.pk}))
             current_slide = display.current_slide
             slide = current_slide.next(form.cleaned_data['direction'])
             next_segment = None
@@ -85,17 +97,21 @@ def form_valid(self, form):
                             if current_segment.slides.first() and form.cleaned_data['direction'] == 'forward':
                                 slide = current_segment.slides.first()
                             elif form.cleaned_data['direction'] == 'reverse':
-                                slide = current_segment.next_with_slides(form.cleaned_data['direction']).get_last_slide()
+                                slide = current_segment.next_with_slides(
+                                    form.cleaned_data['direction']).get_last_slide()
                             elif form.cleaned_data['direction'] == 'forward':
-                                slide = current_segment.next_with_slides(form.cleaned_data['direction']).get_first_slide()
+                                slide = current_segment.next_with_slides(
+                                    form.cleaned_data['direction']).get_first_slide()
                         else:  # ..if current_slide.segment
                             current_segment = current_slide.segment
                             if form.cleaned_data['direction'] == 'reverse' and current_segment.included_deck:
                                 slide = current_segment.included_deck.slides.last()
                             elif form.cleaned_data['direction'] == 'reverse':
-                                slide = current_segment.next_with_slides(form.cleaned_data['direction']).get_last_slide()
+                                slide = current_segment.next_with_slides(
+                                    form.cleaned_data['direction']).get_last_slide()
                             elif form.cleaned_data['direction'] == 'forward':
-                                slide = current_segment.next_with_slides(form.cleaned_data['direction']).get_first_slide()
+                                slide = current_segment.next_with_slides(
+                                    form.cleaned_data['direction']).get_first_slide()
                     except AttributeError:
                         slide = current_slide
                 elif show.advance_loop:
@@ -114,7 +130,7 @@ def form_valid(self, form):
         else:
             slide = Slide.objects.get(pk=form.cleaned_data['slide_pk'])
         slide.send_to_display(show.displays.all(), show=show)
-        return HttpResponseRedirect(reverse('show', kwargs={'pk':show.pk}))
+        return HttpResponseRedirect(reverse('show', kwargs={'pk': show.pk}))
 
 
 class AdvanceModeView(UpdateView):