Own browser UI sessions and shared navigation

src/common/diffNavigation.ts

@@ -0,0 +1,25 @@
+import { stepCyclicIndex } from "octagonal-wheels/collection";
+
+export function navigateDiffNodes(
+    root: ParentNode,
+    selector: string,
+    navigation: {
+        currentDiffIndex: number;
+        diffNavIndicator: { setText(text: string): void };
+    },
+    direction: "prev" | "next"
+): void {
+    const diffElements = root.querySelectorAll<HTMLElement>(selector);
+    if (diffElements.length === 0) return;
+
+    const previousFocused = root.querySelector(".diff-focused");
+    if (previousFocused) {
+        previousFocused.classList.remove("diff-focused");
+    }
+
+    navigation.currentDiffIndex = stepCyclicIndex(navigation.currentDiffIndex, diffElements.length, direction);
+    const target = diffElements[navigation.currentDiffIndex];
+    target.classList.add("diff-focused");
+    target.scrollIntoView({ behavior: "smooth", block: "center" });
+    navigation.diffNavIndicator.setText(`${navigation.currentDiffIndex + 1}/${diffElements.length}`);
+}