Refactoring: fix GPX-track view

Models/ThemeConfig/Conversion/Validation.ts

@@ -891,7 +891,7 @@ export class ValidateLayer extends DesugaringStep<LayerConfigJson> {
                     throw "A special layer cannot have presets"
                 }
                 // Check that a preset will be picked up by the layer itself
-                const baseTags = TagUtils.Tag(json.source.osmTags)
+                const baseTags = TagUtils.Tag(json.source["osmTags"])
                 for (let i = 0; i < json.presets.length; i++) {
                     const preset = json.presets[i]
                     const tags: { k: string; v: string }[] = new And(

Models/ThemeConfig/LayerConfig.ts

@@ -618,17 +618,26 @@ export default class LayerConfig extends WithContextLoader {
             filterDocs.push(new Title("Filters", 4))
             filterDocs.push(...this.filters.map((filter) => filter.GenerateDocs()))
         }
+
+        const tagsDescription = []
+        if (this.source === null) {
+            tagsDescription.push(
+                new Title("Basic tags for this layer", 2),
+                "Elements must have the all of following tags to be shown on this layer:",
+                new List(neededTags.map((t) => t.asHumanString(true, false, {}))),
+                overpassLink
+            )
+        } else {
+            tagsDescription.push("This is a special layer - data is not sourced from OpenStreetMap")
+        }
+
         return new Combine([
             new Combine([new Title(this.id, 1), iconImg, this.description, "\n"]).SetClass(
                 "flex flex-col"
             ),
             new List(extraProps),
             ...usingLayer,
-
-            new Title("Basic tags for this layer", 2),
-            "Elements must have the all of following tags to be shown on this layer:",
-            new List(neededTags.map((t) => t.asHumanString(true, false, {}))),
-            overpassLink,
+            ...tagsDescription,
             new Title("Supported attributes", 2),
             quickOverview,
             ...this.tagRenderings.map((tr) => tr.GenerateDocumentation()),

Models/ThemeConfig/LayoutConfig.ts

@@ -291,6 +291,9 @@ export default class LayoutConfig implements LayoutInformation {
             return undefined
         }
         for (const layer of this.layers) {
+            if (!layer.source) {
+                continue
+            }
             if (layer.source.osmTags.matchesProperties(tags)) {
                 return layer
             }