From d11733442d27ef45ad6c5ab0f34376377b15bfb3 Mon Sep 17 00:00:00 2001
From: Christopher Charbonneau Wells <chris@chrxs.net>
Date: Thu, 24 Aug 2017 14:54:01 -0400
Subject: [PATCH] Add a diaper change types over time report.

---
 core/models.py                              |  4 +-
 reports/templates/reports/diaperchange.html |  8 +--
 reports/urls.py                             |  4 +-
 reports/utils.py                            | 37 +++++++++++
 reports/views.py                            | 73 ++++++++++++++-------
 5 files changed, 96 insertions(+), 30 deletions(-)
 create mode 100644 reports/utils.py

diff --git a/core/models.py b/core/models.py
index 2b831836..523a8ea3 100644
--- a/core/models.py
+++ b/core/models.py
@@ -29,8 +29,8 @@ class Child(models.Model):
     def name(self, reverse=False):
         if reverse:
             return '{}, {}'.format(self.last_name, self.first_name)
-        else:
-            return '{} {}'.format(self.first_name, self.last_name)
+
+        return '{} {}'.format(self.first_name, self.last_name)
 
 
 class DiaperChange(models.Model):
diff --git a/reports/templates/reports/diaperchange.html b/reports/templates/reports/diaperchange.html
index f982abdc..77c861ea 100644
--- a/reports/templates/reports/diaperchange.html
+++ b/reports/templates/reports/diaperchange.html
@@ -3,11 +3,11 @@
 {% block title %}Diaper Change Report - {{ object }}{% endblock %}
 
 {% block content %}
-    <div>
-        Diaper change report for {{ object }}.
+    <div class="jumbotron jumbotron-fluid text-center">
+        <h1 class="display-3">Diaper Change Reports</h1>
+        <h2 class="text-muted">{{ object }}</h2>
     </div>
-
-    <div style="min-height: 600px;">
+    <div class="container-fluid">
         {{ html|safe }}
     </div>
 
diff --git a/reports/urls.py b/reports/urls.py
index dd6ddc40..99fe61da 100644
--- a/reports/urls.py
+++ b/reports/urls.py
@@ -6,8 +6,8 @@ from django.conf.urls import url
 from . import views
 
 urlpatterns = [
-    url(r'^reports/(?P<slug>[^/.]+)/changes/$',
-        views.DiaperChangeReport.as_view(), name='report-diaperchange'),
+    url(r'^reports/changes/(?P<slug>[^/.]+)/$',
+        views.DiaperChangesChildReport.as_view(), name='report-diaperchange'),
     url(r'^reports/(?P<slug>[^/.]+)/sleep/$',
         views.SleepReport.as_view(), name='report-sleep'),
 ]
diff --git a/reports/utils.py b/reports/utils.py
new file mode 100644
index 00000000..678c4e69
--- /dev/null
+++ b/reports/utils.py
@@ -0,0 +1,37 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+
+def default_graph_layout_options():
+    """Default layout options for all graphs.
+    """
+    return {
+        'font': {
+            'color': 'rgba(0, 0, 0, 1)',
+            # Bootstrap 4 font family.
+            'family': '-apple-system, BlinkMacSystemFont, "Segoe UI", '
+                      'Roboto, "Helvetica Neue", Arial, sans-serif, '
+                      '"Apple Color Emoji", "Segoe UI Emoji", '
+                      '"Segoe UI Symbol"',
+            'size': 14,
+        },
+        'margin': {'b': 40, 't': 40},
+        'xaxis': {
+            'titlefont': {
+                'color': 'rgba(0, 0, 0, 0.54)'
+            }
+        },
+        'yaxis': {
+            'titlefont': {
+                'color': 'rgba(0, 0, 0, 0.54)'
+            }
+        }
+    }
+
+
+def split_graph_output(output):
+    """Split out of a Plotly graph in to html and javascript.
+    """
+    html, javascript = output.split('<script')
+    javascript = '<script' + javascript
+    return html, javascript
diff --git a/reports/views.py b/reports/views.py
index 93634eed..7fbd1bc3 100644
--- a/reports/views.py
+++ b/reports/views.py
@@ -2,7 +2,7 @@
 from __future__ import unicode_literals
 
 from django.contrib.auth.mixins import PermissionRequiredMixin
-from django.db.models import Count
+from django.db.models import Count, Case, When
 from django.db.models.functions import TruncDate
 from django.views.generic.detail import DetailView
 
@@ -11,40 +11,69 @@ import plotly.graph_objs as go
 
 from core.models import Child, DiaperChange
 
+from .utils import default_graph_layout_options, split_graph_output
 
-class DiaperChangeReport(PermissionRequiredMixin, DetailView):
+
+class DiaperChangesChildReport(PermissionRequiredMixin, DetailView):
     """All sleep data for a child."""
     model = Child
     permission_required = ('core.view_child',)
     template_name = 'reports/diaperchange.html'
 
-    def get_context_data(self, **kwargs):
-        context = super(DiaperChangeReport, self).get_context_data(**kwargs)
-        child = context['object']
+    def __init__(self):
+        super(DiaperChangesChildReport, self).__init__()
+        self.html = ''
+        self.javascript = ''
 
-        # TODO: Move this logic to the model? Where should data processing like
-        # this happen?
-        changes = DiaperChange.objects.filter(child=child)\
-            .annotate(date=TruncDate('time'))\
-            .values('date')\
-            .annotate(count=Count('id'))\
+    def get_context_data(self, **kwargs):
+        context = super(DiaperChangesChildReport, self).get_context_data(**kwargs)
+        child = context['object']
+        self._change_types_over_time(child)
+        context['html'] = self.html
+        context['javascript'] = self.javascript
+        return context
+
+    def _change_types_over_time(self, child):
+        changes = DiaperChange.objects.filter(child=child) \
+            .annotate(date=TruncDate('time')) \
+            .values('date') \
+            .annotate(wet_count=Count(Case(When(wet=True, then=1)))) \
+            .annotate(solid_count=Count(Case(When(solid=True, then=1)))) \
+            .annotate(total=Count('id')) \
             .order_by('-date')
 
-        trace1 = go.Scatter(
+        solid_trace = go.Scatter(
+            mode='markers',
+            name='Solid changes',
             x=list(changes.values_list('date', flat=True)),
-            y=list(changes.values_list('count', flat=True))
+            y=list(changes.values_list('solid_count', flat=True)),
         )
+        wet_trace = go.Scatter(
+            mode='markers',
+            name='Wet changes',
+            x=list(changes.values_list('date', flat=True)),
+            y=list(changes.values_list('wet_count', flat=True))
+        )
+        total_trace = go.Scatter(
+            name='Total changes',
+            x=list(changes.values_list('date', flat=True)),
+            y=list(changes.values_list('total', flat=True))
+        )
+
+        layout_args = default_graph_layout_options()
+        layout_args['barmode'] = 'stack'
+        layout_args['title'] = 'Diaper change types over time'
+        layout_args['xaxis']['title'] = 'Date'
+        layout_args['yaxis']['title'] = 'Number of changes'
+
         fig = go.Figure({
-            "data": [trace1],
-            "layout": go.Layout(title='Diaper Changes')
+            'data': [solid_trace, wet_trace, total_trace],
+            'layout': go.Layout(**layout_args)
         })
-        div = plotly.plot(fig, output_type='div', include_plotlyjs=False)
-        html, javascript = div.split('<script')
-
-        context['html'] = html
-        context['javascript'] = '<script' + javascript
-
-        return context
+        output = plotly.plot(fig, output_type='div', include_plotlyjs=False)
+        html, javascript = split_graph_output(output)
+        self.html += '<a name="change_types_over_time">' + html
+        self.javascript += javascript
 
 
 class SleepReport(PermissionRequiredMixin, DetailView):