add missing src/detail-route.mjs from template

src/detail-route.mjs

@@ -0,0 +1,58 @@
+import { ValueStoreRoute } from "./routes.mjs";
+
+/**
+ * Route to represent a slice of the masters list of values.
+ *
+ * @property {Route} master route holding the master records
+ */
+export class DetailRoute extends ValueStoreRoute {
+  /**
+   * Route holding the list ov values
+   * @return {Route} our master
+   */
+  get master() {
+    return this.parent;
+  }
+
+  /**
+   * @return {Promise<any>} 1st. entry
+   */
+  async first() {
+    return this.master.value[0];
+  }
+
+  /**
+   * @return {any} last entry
+   */
+  async last() {
+    return this.master.value[this.master.value.length - 1];
+  }
+
+  /**
+   * @return {any} previous value
+   */
+  async previous() {
+    const i = this.master.value.indexOf(this.value);
+    if (i > 0) {
+      return this.master.value[i - 1];
+    }
+  }
+
+  /**
+   * @return {Promise<any>} next value
+   */
+  async next() {
+    const i = this.master.value.indexOf(this.value);
+    if (i >= 0) {
+      return this.master.value[i + 1];
+    }
+  }
+
+  async valueFor(transition) {
+    for await (const value of this.master.iteratorFor(transition)) {
+      if (this.isAcceptable(value, transition.params)) {
+        return value;
+      }
+    }
+  }
+}