Initial montly expenses (#526)

4 files changed, 38 insertions, 1 deletions

diff --git a/ihatemoney/models.py b/ihatemoney/models.py
index 250f009..8a7e273 100644
--- a/ihatemoney/models.py
+++ b/ihatemoney/models.py
@@ -95,6 +95,18 @@ class Project(db.Model):
         ]
 
     @property
+    def monthly_stats(self):
+        """Compute expenses by month
+
+        :return: a dict of years mapping to a dict of months mapping to the amount
+        :rtype dict:
+        """
+        monthly = defaultdict(lambda: defaultdict(float))
+        for bill in self.get_bills().all():
+            monthly[bill.date.year][bill.date.month] += bill.amount
+        return monthly
+
+    @property
     def uses_weights(self):
         return len([i for i in self.members if i.weight != 1]) > 0
 
diff --git a/ihatemoney/static/css/main.css b/ihatemoney/static/css/main.css
index 43df23d..1a7dc1f 100644
--- a/ihatemoney/static/css/main.css
+++ b/ihatemoney/static/css/main.css
@@ -311,8 +311,9 @@ footer .footer-left {
   background: url("../images/see.png") no-repeat right;
 }
 
-#bill_table {
+#bill_table, #monthly_stats {
   margin-top: 30px;
+  margin-bottom: 30px;
 }
 
 .project-actions > .delete,
@@ -487,3 +488,9 @@ footer .icon svg {
 .icon.icon-white {
   fill: white;
 }
+
+/* align the first column */
+#monthly_stats tr *:first-child {
+  text-align: right;
+  width: 200px;
+}
diff --git a/ihatemoney/templates/statistics.html b/ihatemoney/templates/statistics.html
index 0cfe1f2..539781f 100644
--- a/ihatemoney/templates/statistics.html
+++ b/ihatemoney/templates/statistics.html
@@ -21,6 +21,7 @@
 
 
 {% block content %}
+    <h2>{{ _("Balance") }}</h2>
     <table id="bill_table" class="split_bills table table-striped">
         <thead><tr><th>{{ _("Who?") }}</th><th>{{ _("Paid") }}</th><th>{{ _("Spent") }}</th></tr></thead>
     <tbody>
@@ -33,5 +34,17 @@
     {% endfor %}
     </tbody>
     </table>
+    <h2>{{ _("Expenses by Month") }}</h2>
+    <table id="monthly_stats" class="table table-striped">
+        <thead><tr><th>{{ _("Period") }}</th><th>{{ _("Spent") }}</th></tr></thead>
+    <tbody>
+    {% for month in months %}
+            <tr>
+                <td>{{ _(month.strftime("%B")) }} {{ month.year }}</td>
+                <td>{{ "%0.2f"|format(monthly_stats[month.year][month.month]) }}</td>
+            </tr>
+    {% endfor %}
+    </tbody>
+    </table>
 
 {% endblock %}
diff --git a/ihatemoney/web.py b/ihatemoney/web.py
index be39feb..d45190c 100644
--- a/ihatemoney/web.py
+++ b/ihatemoney/web.py
@@ -55,6 +55,8 @@ from ihatemoney.utils import (
     get_members,
     same_bill,
 )
+from datetime import datetime
+from dateutil.relativedelta import relativedelta
 
 main = Blueprint("main", __name__)
 
@@ -737,9 +739,12 @@ def settle_bill():
 @main.route("/<project_id>/statistics")
 def statistics():
     """Compute what each member has paid and spent and display it"""
+    today = datetime.now()
     return render_template(
         "statistics.html",
         members_stats=g.project.members_stats,
+        monthly_stats=g.project.monthly_stats,
+        months=[today - relativedelta(months=i) for i in range(12)],
         current_view="statistics",
     )