Add monthly donation goal to home page sidebar

This uses the data in the financials table to generate a donation goal
meter at the top of the home page's sidebar. It uses the new-ish HTML
<meter> element, which will automatically change colors as it hits
different thresholds.

tildes/scss/modules/_donation.scss

@@ -0,0 +1,26 @@
+// Copyright (c) 2019 Tildes contributors <code@tildes.net>
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+.donation-goal {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+
+  padding: 0.4rem 0.4rem 0;
+  margin: 1rem 0;
+  border: 1px solid;
+  border-color: inherit;
+
+  font-size: 0.6rem;
+  text-align: center;
+
+  header {
+    font-weight: bold;
+  }
+
+  meter {
+    width: 100%;
+    height: 0.4rem;
+    margin: 0.4rem 0 0.2rem;
+  }
+}

tildes/scss/modules/_site-footer.scss

@@ -6,14 +6,7 @@
   padding-bottom: 1rem;
 
   font-size: 0.6rem;
-  font-style: italic;
   text-align: center;
-
-  p {
-    max-width: none;
-    margin-bottom: 0.2rem;
-    line-height: 0.7rem;
-  }
 }
 
 .site-footer-links {
@@ -23,8 +16,6 @@
 
   list-style-type: none;
   margin: 0;
-  margin-top: 0.4rem;
-  font-style: normal;
 }
 
 .site-footer-link {

tildes/scss/styles.scss

@@ -14,6 +14,7 @@
 @import "modules/chip";
 @import "modules/comment";
 @import "modules/divider";
+@import "modules/donation";
 @import "modules/empty";
 @import "modules/form";
 @import "modules/group";

tildes/scss/themes/_theme_base.scss

@@ -82,6 +82,40 @@
     background-color: map-get($theme, "background-primary");
   }
 
+  meter {
+    // Crazy styles to get this to work adapted from Spectre.css's _meters.scss
+    background: map-get($theme, "background-secondary");
+
+    &::-webkit-meter-bar {
+      background: map-get($theme, "background-secondary");
+    }
+
+    // For some mysterious reason, none of the below rules can be merged
+    &::-webkit-meter-optimum-value {
+      background: map-get($theme, "success");
+    }
+
+    &:-moz-meter-optimum::-moz-meter-bar {
+      background: map-get($theme, "success");
+    }
+
+    &::-webkit-meter-suboptimum-value {
+      background: map-get($theme, "warning");
+    }
+
+    &:-moz-meter-sub-optimum::-moz-meter-bar {
+      background: map-get($theme, "warning");
+    }
+
+    &::-webkit-meter-even-less-good-value {
+      background: map-get($theme, "error");
+    }
+
+    &:-moz-meter-sub-sub-optimum::-moz-meter-bar {
+      background: map-get($theme, "error");
+    }
+  }
+
   tbody tr:nth-of-type(2n + 1) {
     background-color: map-get($theme, "background-secondary");
   }

tildes/tildes/templates/base.jinja2

@@ -133,8 +133,6 @@
     </div>
   {% endif %}
 
-  <p>Tildes is a non-profit site that respects its users and prioritizes quality content.</p>
-  <p>It has no advertising, no investors, and is supported by <a href="https://docs.tildes.net/donate">your donations</a>.</p>
   <ul class="site-footer-links">
     <li class="site-footer-link"><a href="https://docs.tildes.net">Docs</a></li>
     <li class="site-footer-link"><a href="https://blog.tildes.net">Blog</a></li>

tildes/tildes/templates/home.jinja2

@@ -33,6 +33,10 @@
 {% block sidebar %}
   {{ search_form() }}
 
+  {% if financial_data %}
+    {{ donation_goal(financial_data, current_time) }}
+  {% endif %}
+
   <h2>Home</h2>
 
   {% if request.user %}
@@ -87,3 +91,22 @@
     </ul>
   {% endif %}
 {% endblock %}
+
+{% macro donation_goal(financial_data, current_time) %}
+  <div class="donation-goal">
+    <header>{{ current_time.strftime("%B %Y") }} donation goal</header>
+    <meter
+      max="{{ financial_data["goal"] }}"
+      low="{{ financial_data["expense"] }}"
+      high="{{ financial_data["goal"] // 4 * 3 }}" {# 3/4 of the goal #}
+      optimum="{{ financial_data["goal"] - 1 }}" {# just needs to be between high and max #}
+      value="{{ financial_data["income"] }}"
+      title="${{ financial_data["income"] }} / ${{ financial_data["goal"] }} (USD)"
+    ></meter>
+
+    <p>
+      Tildes is a non-profit site with no ads or investors, funded entirely by donations.<br>
+      <a href="https://docs.tildes.net/donate">Please donate</a> to support its continued development!
+    </p>
+  </div>
+{% endmacro %}

tildes/tildes/views/topic.py

@@ -4,7 +4,8 @@
 """Views related to posting/viewing topics and comments on them."""
 
 from collections import namedtuple
-from typing import Any, Optional, Union
+from decimal import Decimal
+from typing import Any, Dict, Optional, Union
 
 from datetime import timedelta
 from marshmallow import missing, ValidationError
@@ -14,7 +15,8 @@ from pyramid.renderers import render_to_response
 from pyramid.request import Request
 from pyramid.response import Response
 from pyramid.view import view_config
-from sqlalchemy import cast
+from sqlalchemy import cast, func
+from sqlalchemy.orm.session import Session
 from sqlalchemy.sql.expression import any_, desc, text
 from sqlalchemy_utils import Ltree
 from webargs.pyramidparser import use_kwargs
@@ -28,8 +30,9 @@ from tildes.enums import (
     TopicSortOption,
 )
 from tildes.lib.database import TagList
-from tildes.lib.datetime import SimpleHoursPeriod
+from tildes.lib.datetime import SimpleHoursPeriod, utc_now
 from tildes.models.comment import Comment, CommentNotification, CommentTree
+from tildes.models.financials import Financials
 from tildes.models.group import Group, GroupWikiPage
 from tildes.models.log import LogComment, LogTopic
 from tildes.models.topic import Topic, TopicSchedule, TopicVisit
@@ -262,6 +265,11 @@ def get_group_topics(
     else:
         most_recent_scheduled_topics = None
 
+    if is_home_page:
+        financial_data = _get_financial_data(request.db_session)
+    else:
+        financial_data = None
+
     return {
         "group": request.context,
         "groups": groups,
@@ -281,6 +289,8 @@ def get_group_topics(
         "wiki_has_index": wiki_has_index,
         "subgroups": subgroups,
         "most_recent_scheduled_topics": most_recent_scheduled_topics,
+        "financial_data": financial_data,
+        "current_time": utc_now(),
     }
 
 
@@ -488,3 +498,22 @@ def _get_default_settings(request: Request, order: Any) -> DefaultSettings:  # n
             default_period = None
 
     return DefaultSettings(order=default_order, period=default_period)
+
+
+def _get_financial_data(db_session: Session) -> Optional[Dict[str, Decimal]]:
+    """Return financial data used to render the donation goal box."""
+    # get the total sum for each entry type in the financials table relevant to today
+    financial_totals = (
+        db_session.query(Financials.entry_type, func.sum(Financials.amount))
+        .filter(Financials.date_range.op("@>")(text("CURRENT_DATE")))
+        .group_by(Financials.entry_type)
+        .all()
+    )
+
+    financial_data = {entry[0].name.lower(): entry[1] for entry in financial_totals}
+
+    # if any of the entry types were missing, the data won't be usable
+    if any(key not in financial_data for key in ("expense", "goal", "income")):
+        return None
+
+    return financial_data