feat: pwa notifications

tracker/models.py

@@ -41,6 +41,12 @@ class ScheduledDose(models.Model):
     amount = models.CharField(
         max_length=20, default="1/4", help_text='Free text, e.g. "1/4", "1", "5 mg".'
     )
+    reminder_time = models.TimeField(
+        null=True,
+        blank=True,
+        help_text="Send a push reminder at this time if the dose isn't ticked off. "
+        "Leave empty for no reminder.",
+    )
     is_active = models.BooleanField(default=True)
 
     class Meta:
@@ -92,6 +98,30 @@ class DoseLog(models.Model):
         return super().save(*args, **kwargs)
 
 
+class ReminderSent(models.Model):
+    """One row per dose per day once its reminder has gone out.
+
+    This is what stops a reminder being re-sent every time the cron job ticks.
+    """
+
+    scheduled_dose = models.ForeignKey(
+        ScheduledDose, on_delete=models.CASCADE, related_name="reminders"
+    )
+    date = models.DateField()
+    sent_at = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        ordering = ["-sent_at"]
+        constraints = [
+            models.UniqueConstraint(
+                fields=["scheduled_dose", "date"], name="unique_reminder_per_day"
+            )
+        ]
+
+    def __str__(self):
+        return f"{self.date} — {self.scheduled_dose}"
+
+
 class PulseReading(models.Model):
     """One heart-rate measurement per day, in beats per minute."""