Use through model on judgment.judges to preserve ordering

This way, the order in which the judges are added to the decision in the
admin area is preserved when presented to the user. We don't have to
explicitly add an ordering field -- the editor must just enter the
judges in the correct order.

We need to tweak some of the older migrations to work with theh existing
data, since nothing is changing under the hood. Only Django's view of
the database and how it works with it is changing.

peachjam/admin.py

@@ -36,6 +36,7 @@
     AttachedFiles,
     Attorney,
     Author,
+    Bench,
     Book,
     CaseNumber,
     CitationLink,
@@ -586,6 +587,14 @@ class AttachedFilesInline(BaseAttachmentFileInline):
     form = AttachedFilesForm
 
 
+class BenchInline(admin.TabularInline):
+    # by using an inline, the ordering of the judges is preserved
+    model = Bench
+    extra = 3
+    verbose_name = gettext_lazy("judge")
+    verbose_name_plural = gettext_lazy("judges")
+
+
 class JudgmentAdminForm(DocumentForm):
     hearing_date = forms.DateField(widget=DateSelectorWidget(), required=False)
 
@@ -607,7 +616,11 @@ def save(self, *args, **kwargs):
 class JudgmentAdmin(ImportExportMixin, DocumentAdmin):
     form = JudgmentAdminForm
     resource_class = JudgmentResource
-    inlines = [CaseNumberAdmin, AttachedFilesInline] + DocumentAdmin.inlines
+    inlines = [
+        BenchInline,
+        CaseNumberAdmin,
+        AttachedFilesInline,
+    ] + DocumentAdmin.inlines
     filter_horizontal = ("judges", "attorneys")
     list_filter = (*DocumentAdmin.list_filter, "court")
     fieldsets = copy.deepcopy(DocumentAdmin.fieldsets)
@@ -620,8 +633,7 @@ class JudgmentAdmin(ImportExportMixin, DocumentAdmin):
     fieldsets[0][1]["fields"].insert(8, "serial_number_override")
     fieldsets[0][1]["fields"].insert(9, "serial_number")
     fieldsets[0][1]["fields"].append("hearing_date")
-    fieldsets[1][1]["fields"].insert(0, "judges")
-    fieldsets[1][1]["fields"].insert(1, "attorneys")
+    fieldsets[1][1]["fields"].insert(0, "attorneys")
 
     fieldsets[2][1]["classes"] = ["collapse"]
     fieldsets[3][1]["fields"].extend(
@@ -650,7 +662,7 @@ class PredicateAdmin(admin.ModelAdmin):
 
 class IngestorSettingInline(admin.TabularInline):
     model = IngestorSetting
-    extra = 1
+    extra = 3
 
 
 @admin.register(Ingestor)

peachjam/migrations/0002_casenumber_judge_judgment_judgmentmediasummaryfile_mattertype.py

@@ -58,7 +58,6 @@ class Migration(migrations.Migration):
                         to="peachjam.author",
                     ),
                 ),
-                ("judges", models.ManyToManyField(blank=True, to="peachjam.Judge")),
             ],
             options={
                 "ordering": ["title"],
@@ -154,4 +153,47 @@ class Migration(migrations.Migration):
                 ),
             ],
         ),
+        migrations.CreateModel(
+            name="Bench",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "judge",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.PROTECT,
+                        to="peachjam.judge",
+                        verbose_name="judge",
+                    ),
+                ),
+                (
+                    "judgment",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="bench",
+                        to="peachjam.judgment",
+                        verbose_name="judgment",
+                    ),
+                ),
+            ],
+            options={
+                "db_table": "peachjam_judgment_judges",
+                "ordering": ("pk",),
+                "unique_together": {("judgment", "judge")},
+            },
+        ),
+        migrations.AddField(
+            model_name="judgment",
+            name="judges",
+            field=models.ManyToManyField(
+                through="peachjam.Bench", to="peachjam.Judge", verbose_name="judges"
+            ),
+        ),
     ]

peachjam/migrations/0042_i18n_models.py

@@ -879,7 +879,10 @@ class Migration(migrations.Migration):
             model_name="judgment",
             name="judges",
             field=models.ManyToManyField(
-                blank=True, to="peachjam.Judge", verbose_name="judges"
+                blank=True,
+                through="peachjam.Bench",
+                to="peachjam.Judge",
+                verbose_name="judges",
             ),
         ),
         migrations.AlterField(

peachjam/migrations/0092_alter_judge_options.py

@@ -0,0 +1,21 @@
+# Generated by Django 3.2.16 on 2023-07-21 08:51
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("peachjam", "0091_peachjamsettings_mailchimp_form_url"),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name="judge",
+            options={
+                "ordering": ("name",),
+                "verbose_name": "judge",
+                "verbose_name_plural": "judges",
+            },
+        ),
+    ]

peachjam/models/judgment.py

@@ -30,10 +30,7 @@ class Judge(models.Model):
     description = models.TextField(_("description"), blank=True)
 
     class Meta:
-        ordering = (
-            "pk",
-            "name",
-        )
+        ordering = ("name",)
         verbose_name = _("judge")
         verbose_name_plural = _("judges")
 
@@ -140,6 +137,29 @@ def save(self, *args, **kwargs):
         return super().save(*args, **kwargs)
 
 
+class Bench(models.Model):
+    # This model is not strictly necessary, as it's almost identical to the default that Django creates
+    # for a many-to-many relationship. However, by creating it, we can indicate that the ordering should
+    # be on the PK of the model. This means that we can preserve the ordering of Judges as the are
+    # entered in the admin interface.
+    #
+    # To use this effectively, views that need the judges to be ordered, should call "judgement.bench.all()"
+    # and not "judgment.judges.all()".
+    judgment = models.ForeignKey(
+        "Judgment",
+        related_name="bench",
+        on_delete=models.CASCADE,
+        verbose_name=_("judgment"),
+    )
+    judge = models.ForeignKey(Judge, on_delete=models.PROTECT, verbose_name=_("judge"))
+
+    class Meta:
+        # this is to re-use the existing table rather than creating a new one
+        db_table = "peachjam_judgment_judges"
+        ordering = ("pk",)
+        unique_together = ("judgment", "judge")
+
+
 class Judgment(CoreDocument):
     court = models.ForeignKey(
         Court, on_delete=models.PROTECT, null=True, verbose_name=_("court")
@@ -151,7 +171,9 @@ class Judgment(CoreDocument):
         related_name="judgments",
         blank=True,
     )
-    judges = models.ManyToManyField(Judge, blank=True, verbose_name=_("judges"))
+    judges = models.ManyToManyField(
+        Judge, blank=True, verbose_name=_("judges"), through=Bench
+    )
     attorneys = models.ManyToManyField(
         Attorney, blank=True, verbose_name=_("attorneys")
     )

peachjam/templates/peachjam/layouts/document_detail.html

@@ -205,14 +205,14 @@ <h1>{{ document.title }}</h1>
                             </dd>
                           {% endif %}
                         {% endwith %}
-                        {% with document.judges.all as judges %}
+                        {% with document.bench.all as judges %}
                           {% if judges %}
                             <dt>
                               {% trans 'Judges' %}
                             </dt>
                             <dd class="text-muted">
-                              {% for judge in judges %}
-                                {{ judge.name }}
+                              {% for bench in judges %}
+                                {{ bench.judge.name }}
                                 {% if not forloop.last %},{% endif %}
                               {% endfor %}
                             </dd>