Add GPX trail maps to blog posts

This adds a trail flow block so posts can include attached GPX files as
interactive maps with route display, elevation charts, activity
summaries, and start/finish markers.

The trail assets are loaded only when needed, keeping the shared
templates clean while vendoring the Leaflet dependencies required for
offline, self-hosted map rendering.

2 files changed, 72 insertions, 0 deletions

diff --git a/templates/blocks/markdown.html b/templates/blocks/markdown.html
new file mode 100644
index 0000000..8ee0a42
--- /dev/null
+++ b/templates/blocks/markdown.html
@@ -0,0 +1 @@
+{{ this.text }}
diff --git a/templates/blocks/trail.html b/templates/blocks/trail.html
new file mode 100644
index 0000000..b32b7c1
--- /dev/null
+++ b/templates/blocks/trail.html
@@ -0,0 +1,71 @@
+{% set trail_gpx = record.attachments.get(this.trail_gpx) if this.trail_gpx else none %}
+{% set activity_gpx = record.attachments.get(this.activity_gpx) if this.activity_gpx else none %}
+{% if trail_gpx %}
+  {% set trail_gpx_url = trail_gpx | url(absolute=True, external=False) %}
+{% endif %}
+{% if activity_gpx %}
+  {% set activity_gpx_url = activity_gpx | url(absolute=True, external=False) %}
+{% endif %}
+{% if trail_gpx or activity_gpx %}
+  <figure class="trail"
+          {% if trail_gpx %}data-trail-gpx-url="{{ trail_gpx_url }}"{% endif %}
+          {% if activity_gpx %}data-activity-gpx-url="{{ activity_gpx_url }}"{% endif %}>
+    <figcaption class="visually-hidden">Interactive map of the trail</figcaption>
+    <div data-trail-map role="region" aria-label="Interactive trail map"></div>
+    <details>
+      <summary>Trail details</summary>
+      <div>
+        <div data-trail-chart role="region" aria-label="Trail elevation profile"></div>
+        <div data-trail-summary>
+          <table aria-label="Trail summary">
+            <tbody>
+              <tr>
+                <th scope="row">Distance:</th>
+                <td data-trail-distance></td>
+                <th scope="row">Time:</th>
+                <td data-trail-time></td>
+                <th scope="row">Overall pace:</th>
+                <td data-trail-pace></td>
+              </tr>
+              <tr>
+                <th scope="row">Maximum elevation:</th>
+                <td data-trail-maximum-elevation></td>
+                <th scope="row">Minimum elevation:</th>
+                <td data-trail-minimum-elevation></td>
+                <th scope="row">Average elevation:</th>
+                <td data-trail-average-elevation></td>
+              </tr>
+              <tr>
+                <th scope="row">Ascent:</th>
+                <td data-trail-ascent></td>
+                <th scope="row">Descent:</th>
+                <td data-trail-descent></td>
+              </tr>
+              <tr>
+                <th scope="row">Average speed:</th>
+                <td data-trail-average-speed></td>
+                <th scope="row">Maximum speed:</th>
+                <td data-trail-maximum-speed></td>
+              </tr>
+            </tbody>
+          </table>
+        </div>
+        <p>
+          <a href="{% if trail_gpx %}{{ trail_gpx_url }}{% else %}{{ activity_gpx_url }}{% endif %}"
+             download>Download the GPX track</a>
+        </p>
+
+      </div>
+    </details>
+
+    <p data-trail-message role="status" hidden>The interactive trail map could not be loaded.</p>
+    <noscript>
+      <p class="trail-message">JavaScript is required to display the interactive trail map.</p>
+    </noscript>
+  </figure>
+{% else %}
+  <figure class="trail">
+    <figcaption class="visually-hidden">Interactive map of the trail</figcaption>
+    <p class="trail-message" role="status">The interactive trail map could not be loaded.</p>
+  </figure>
+{% endif %}