LIL-123. Add data-liked attr for course item

apps/course/templates/course/_items.html

@@ -1,5 +1,18 @@
 {% load static %}
-<div class="courses__item" data-course data-course-id={{ course.id }} data-likes-count={{ course.likes.count }} {% if course.is_deferred_start %}data-future-course data-future-course-time={{ course.deferred_start_at.timestamp }}{% endif %}>
+{% load data_liked from data_liked %}
+
+<div 
+  class="courses__item" 
+  data-course data-course-id={{ course.id }} 
+  data-likes-count={{ course.likes.count }}
+  {% data_liked user course as liked %}
+  {% if liked %}
+  data-liked=1
+  {% else %}
+  data-liked=0
+  {% endif %}
+  {% if course.is_deferred_start %}data-future-course data-future-course-time={{ course.deferred_start_at.timestamp }}{% endif %}
+  >
   <a class="courses__preview" href="{% url 'course' course.id %}">
     <img class="courses__pic" src="{{ course.cover.url }}" />
     <div class="courses__view">Подробнее</div>
@@ -16,7 +29,8 @@
   <div class="courses__details">
     <a class="courses__theme theme {{ theme_color }}" href="{% url 'courses' %}?category={{ course.category.title }}">{{ course.category | upper }}</a>
     {% if not course.is_free %}
-    <div class="courses__price">{{ course.price|floatformat:"-2" }}$</div>{% endif %}
+    <div class="courses__price">{{ course.price|floatformat:"-2" }}$</div>
+    {% endif %}
   </div>
   <a class="courses__title" href="{% url 'course' course.id %}">{{ course.title }}</a>
   <div class="courses__content">{{ course.short_description }}

apps/course/templatetags/data_liked.py

@@ -0,0 +1,13 @@
+from django import template
+
+from ..models import Like
+
+register = template.Library()
+
+
+@register.simple_tag
+def data_liked(user, course):
+    for like in course.likes.all():
+        if user == like.user:
+            return True
+    return False