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.

1 files changed, 46 insertions, 0 deletions

diff --git a/assets/static/vendor/leaflet-elevation/src/handlers/distance.js b/assets/static/vendor/leaflet-elevation/src/handlers/distance.js
new file mode 100644
index 0000000..fa6fa1d
--- /dev/null
+++ b/assets/static/vendor/leaflet-elevation/src/handlers/distance.js
@@ -0,0 +1,46 @@
+export function Distance() {
+
+	const _ = L.Control.Elevation.Utils;
+
+	let opts     = this.options;
+	let distance = {};
+
+	opts.distanceFactor = opts.imperial ? this.__mileFactor : (opts.distanceFactor || 1); // 1 km = (1000 m)
+	distance.label      = opts.imperial ? "mi" : opts.xLabel;
+
+	return {
+		name: 'distance',
+		required: true,
+		attr: 'dist',
+		unit: distance.label,
+		decimals: 5,
+		pointToAttr: (_, i) => (i > 0 ? this._data[i - 1].dist : 0) + (this._data[i].latlng.distanceTo(this._data[i > 0 ? i - 1 : i].latlng) * opts.distanceFactor) / 1000, // convert back km to meters
+		// stats: { total: _.iSum },
+		onPointAdded: (distance, i) => this.track_info.distance = distance,
+		scale: opts.distance && {
+			axis    : "x",
+			position: "bottom",
+			scale   : "x", // this._chart._x,
+			labelY  : 25,
+			labelX  : () => this._width() + 6,
+			ticks   : () => _.clamp(this._chart._xTicks() / 2, [4, +Infinity]),
+		},
+		grid: opts.distance && {
+			axis      : "x",
+			position  : "bottom",
+			scale     : "x" // this._chart._x,
+		},
+		tooltip: opts.distance && {
+			name: 'x',
+			chart: (item) => L._("x: ") + _.round(item[opts.xAttr], opts.decimalsX) + " " + distance.label,
+			order: 20
+		},
+		summary: opts.distance && {
+			"totlen"  : {
+				label: "Total Length: ",
+				value: (track) => (track.distance || 0).toFixed(2) + ' ' + distance.label,
+				order: 10
+			}
+		}
+	};
+}