Manage search pagination

3 files changed, 63 insertions, 19 deletions

diff --git a/chimere/models.py b/chimere/models.py
index 46a778c..451596b 100644
--- a/chimere/models.py
+++ b/chimere/models.py
@@ -609,6 +609,7 @@ class GeographicItem(models.Model):
     search_vector = SearchVectorField(_("Search vector"), blank=True, null=True,
                                       help_text=_("Auto filled at save"))
 
+    geom_attr = ''
     default_values = {}
     json_color_keys = []
 
@@ -861,7 +862,8 @@ class GeographicItem(models.Model):
         raise NotImplementedError()
 
     @classmethod
-    def getGeoJSONs(cls, queryset, limit_to_categories=None, slice=None):
+    def getGeoJSONs(cls, queryset, limit_to_categories=None, slice=None,
+                    check_next=False):
         default_values = copy.copy(cls.default_values)
         q_values = ['json', 'name', 'pk', 'categories__pk'] + \
             cls.json_color_keys
@@ -873,9 +875,8 @@ class GeographicItem(models.Model):
         start, end = 0, None
         if slice:
             start, end = slice
+        has_next = False
         for item in q.all():
-            if end and len(vals) > end:
-                break
             if item['pk'] in added:
                 continue
             if limit_to_categories and \
@@ -884,7 +885,11 @@ class GeographicItem(models.Model):
             added.append(item['pk'])
             if start:
                 start -= 1
+                end -= 1
                 continue
+            if end and len(vals) > end:
+                has_next = True
+                break
             properties = {"pk": item['pk'], "name": item['name'],
                           'key': "{}-{}".format(cls.geom_attr, item['pk'])}
             icon_and_colors, current_categories = \
@@ -905,18 +910,24 @@ class GeographicItem(models.Model):
                 "geometry": geom,
                 "properties": properties
             })
-        return vals
+        if not check_next:
+            return vals
+        return vals, has_next
 
     @classmethod
-    def search(cls, query, area=None, get_json=False, slice=None):
+    def search(cls, query, area=None, get_json=False, slice=None,
+               check_next=False):
         """
         Search items using search_vector
 
         :param query: terms to search
         :param area: area limitation (default None)
         :param get_json: output as json if True else return a queryset
-        :param slice: startting and ending bounds
-        :return: items matching the search query and the area
+        :param slice: starting and ending bounds
+        :param check_next: check if next items are available (only relevant
+        if a slice is provided)
+        :return: items matching the search query - if check next to true
+        also return if next items are available
         """
         subcats = SubCategory.getAvailable(instance=True, area=area)
         q = cls.objects.filter(categories__in=subcats,
@@ -924,11 +935,16 @@ class GeographicItem(models.Model):
                                    query,
                                    config=settings.CHIMERE_SEARCH_LANGUAGE))
         if get_json:
-            return cls.getGeoJSONs(q, slice=slice)
+            return cls.getGeoJSONs(q, slice=slice, check_next=check_next)
         if slice:
-            return q.all()[slice[0]:slice[1]]
+            if not check_next:
+                return q.all()[slice[0]:slice[1]]
+            has_next = q.count() > slice[1]
+            return q.all()[slice[0]:slice[1]], has_next
         else:
-            return q.all()
+            if not check_next:
+                return q.all()
+            return q.all(), False
 
     def update_search_vector(self, save=True):
         """
diff --git a/chimere/templates/search/search.html b/chimere/templates/search/search.html
index d01c16e..67e08d9 100644
--- a/chimere/templates/search/search.html
+++ b/chimere/templates/search/search.html
@@ -18,12 +18,12 @@ var end_do_you_mean = "{% trans '?' %}";
 {% endfor %}
   </ul>
 </div>
-{% if page.has_previous or page.has_next %}
+{% if previous_page_number or next_page_number %}
     <div id='search-nav'>
     <nav>
       <ul class="pager">
-        {% if page.has_previous %}<li class="previous"><a href="#" onclick="haystack_search(this, {{ page.previous_page_number }});">&larr; {% trans "Previous" %}</a></li>{% endif %}
-        {% if page.has_next %}<li class="next"><a href="#" onclick="haystack_search(this, {{ page.next_page_number }});">{% trans "More results..." %} &rarr;</a></li>{% endif %}
+        {% if previous_page_number %}<li class="previous"><a href="#" onclick="haystack_search(this, {{ previous_page_number }});"><i class="fa fa-arrow-circle-left" aria-hidden="true"></i> {% trans "Previous" %}</a></li>{% endif %}
+        {% if next_page_number %}<li class="next"><a href="#" onclick="haystack_search(this, {{ next_page_number }});">{% trans "More results..." %} <i class="fa fa-arrow-circle-right" aria-hidden="true"></i></a></li>{% endif %}
       </ul>
     </nav>
     </div>
diff --git a/chimere/views.py b/chimere/views.py
index ee27d26..d486506 100644
--- a/chimere/views.py
+++ b/chimere/views.py
@@ -1278,23 +1278,51 @@ class SearchView(FormView):
     form_class = forms.SearchForm
     results_per_page = settings.SEARCH_RESULTS_PER_PAGE
 
-    def get_results(self, query, area=None):
-        results = []
+    def get_results(self, query, area=None, page=1):
+        results, has_next = [], False
+        start = (page - 1) * self.results_per_page
+        end = page * self.results_per_page - 1
         for model in [models.Marker, models.Route, models.Polygon]:
-            results += model.search(query, area=area, get_json=True)
-        return results
+            if len(results) > end - len(results):
+                continue
+            res, _has_next = model.search(
+                query, area=area, get_json=True,
+                slice=[start, end],
+                check_next=True)
+            if _has_next:
+                has_next = True
+            if res:
+                if start:
+                    end = end - start
+                    start = 0
+                end -= len(res)
+            results += res
+        return results, has_next
 
     def get_context_data(self, **kwargs):
         context = super(SearchView, self).get_context_data(**kwargs)
         area, area_name = get_area(self.kwargs.get('area_name', None))
         query, results = None, []
+        previous_page_number, next_page_number = None, None
         if "q" in self.request.GET:
             query = self.request.GET['q']
-            results = self.get_results(query, area)
+            try:
+                page = int(self.request.GET.get('page', 1))
+                assert page >= 1
+            except (ValueError, AssertionError):
+                page = 1
+            if page > 1:
+                previous_page_number = page - 1
+            results, has_next = self.get_results(query, area, page=page)
+            if has_next:
+                next_page_number = page + 1
+
         context.update({
             'query': query,
             'results': results,
-            'area_name': area_name
+            'area_name': area_name,
+            'previous_page_number': previous_page_number,
+            'next_page_number': next_page_number
         })
         # (paginator, page) = self.build_page()