From 6298b1228a7313de4375a567d79a7ab046bc2a26 Mon Sep 17 00:00:00 2001
From: Kevin Morris <kevr@0cost.org>
Date: Wed, 15 Sep 2021 11:31:55 -0700
Subject: [PATCH] feat(FastAPI): add templates/partials/widgets/pager.html

A pager that can be used for paginated result tables.

Signed-off-by: Kevin Morris <kevr@0cost.org>
---
 aurweb/filters.py                     | 50 +++++++++++++++++++++++++++
 templates/partials/widgets/pager.html | 26 ++++++++++++++
 2 files changed, 76 insertions(+)
 create mode 100644 aurweb/filters.py
 create mode 100644 templates/partials/widgets/pager.html

diff --git a/aurweb/filters.py b/aurweb/filters.py
new file mode 100644
index 00000000..bb56c656
--- /dev/null
+++ b/aurweb/filters.py
@@ -0,0 +1,50 @@
+from typing import Any, Dict
+
+import paginate
+
+from jinja2 import pass_context
+
+from aurweb import util
+from aurweb.templates import register_filter
+
+
+@register_filter("pager_nav")
+@pass_context
+def pager_nav(context: Dict[str, Any],
+              page: int, total: int, prefix: str) -> str:
+    page = int(page)  # Make sure this is an int.
+
+    pp = context.get("PP", 50)
+
+    # Setup a local query string dict, optionally passed by caller.
+    q = context.get("q", dict())
+
+    search_by = context.get("SeB", None)
+    if search_by:
+        q["SeB"] = search_by
+
+    sort_by = context.get("SB", None)
+    if sort_by:
+        q["SB"] = sort_by
+
+    def create_url(page: int):
+        nonlocal q
+        offset = max(page * pp - pp, 0)
+        qs = util.to_qs(util.extend_query(q, ["O", offset]))
+        return f"{prefix}?{qs}"
+
+    # Use the paginate module to produce our linkage.
+    pager = paginate.Page([], page=page + 1,
+                          items_per_page=pp,
+                          item_count=total,
+                          url_maker=create_url)
+
+    return pager.pager(
+        link_attr={"class": "page"},
+        curpage_attr={"class": "page"},
+        separator="&nbsp",
+        format="$link_first $link_previous ~5~ $link_next $link_last",
+        symbol_first="« First",
+        symbol_previous="‹ Previous",
+        symbol_next="Next ›",
+        symbol_last="Last »")
diff --git a/templates/partials/widgets/pager.html b/templates/partials/widgets/pager.html
new file mode 100644
index 00000000..4809accf
--- /dev/null
+++ b/templates/partials/widgets/pager.html
@@ -0,0 +1,26 @@
+{# A pager widget that can be used for navigation of a number of results.
+
+Inputs required:
+
+    prefix: Request URI prefix used to produce navigation offsets
+    singular: Singular sentence to be translated via tn
+    plural: Plural sentence to be translated via tn
+    PP: The number of results per page
+    O: The current offset value
+    total: The total number of results
+#}
+
+{% set page = ((O / PP) | int) %}
+{% set pages = ((total / PP) | ceil) %}
+
+<div class="pkglist-stats">
+    <p>
+        {{ total | tn(singular, plural) | format(total) }}
+        {{ "Page %d of %d." | tr | format(page + 1, pages) }}
+    </p>
+    {% if pages > 1 %}
+        <p class="pkglist-nav">
+            {{ page | pager_nav(total, prefix) | safe }}
+        <p>
+    {% endif %}
+</div>