Add history chart in categories

nummi/main/static/main/css/plot.css

@@ -24,18 +24,15 @@ table.full-width col.bar {width: auto}
 	right: 0;
 	border-radius: var(--radius) 0 0 var(--radius);
 }
-.plot td.bar.m div:not(.tot) {
-	background: var(--red-1);
-}
-.plot td.bar.p div:not(.tot) {
-	background: var(--green-1);
-}
+.plot td.bar.m div {background: var(--red-1)}
+.plot td.bar.p div {background: var(--green-1)}
 
 .plot td.bar div.tot {
 	z-index: 10;
 	height: .5rem;
-	background: black;
 }
+.plot td.bar.m div.tot {background: var(--red)}
+.plot td.bar.p div.tot {background: var(--green)}
 .plot td.bar div.tot span {
 	position: absolute;
 	display: inline-block;

nummi/main/templates/main/category_form.html

@@ -11,6 +11,9 @@
     <link rel="stylesheet"
           href="{% static 'main/css/table.css' %}"
           type="text/css"/>
+    <link rel="stylesheet"
+          href="{% static 'main/css/plot.css' %}"
+          type="text/css"/>
 {% endblock %}
 {% block body %}
     <h1>
@@ -23,5 +26,7 @@
     {% if form.instance.transactions %}
         <h2>{% translate "Transactions" %}</h2>
         {% include "main/table/transaction.html" %}
+        <h2>{% translate "History" %}</h2>
+        {% include "main/plot/history.html" %}
     {% endif %}
 {% endblock %}

nummi/main/views.py

@@ -228,11 +228,30 @@ class CategoryUpdateView(NummiUpdateView):
     def get_context_data(self, **kwargs):
         data = super().get_context_data(**kwargs)
         category = data["form"].instance
+        _history = (
+            category.transaction_set.values(month=models.functions.TruncMonth("date"))
+            .annotate(
+                sum_p=models.Sum("value", filter=models.Q(value__gt=0)),
+                sum_m=models.Sum("value", filter=models.Q(value__lt=0)),
+                sum=models.Sum("value"),
+            )
+            .order_by("-month")
+        )
+
         return data | {
             "transactions": category.transaction_set.all()[:8],
             "transactions_url": reverse_lazy(
                 "category_transactions", args=(category.pk,)
             ),
+            "history": {
+                "data": _history,
+                "max": max(
+                    _history.aggregate(
+                        max=models.Max("sum_p", default=0),
+                        min=-models.Min("sum_m", default=0),
+                    ).values(),
+                ),
+            },
         }