From 85c2e35b02e92de06f914b26904024281249102a Mon Sep 17 00:00:00 2001
From: Josep M Sobrepere <jm.sobrepere@gmail.com>
Date: Tue, 17 Jun 2025 14:12:46 +0200
Subject: [PATCH] feat: load events from old blocks

---
 src/pages/Explorer/block.state.ts | 71 +++++++++++++++++++++----------
 1 file changed, 48 insertions(+), 23 deletions(-)

diff --git a/src/pages/Explorer/block.state.ts b/src/pages/Explorer/block.state.ts
index 4efad75..5f0ffb7 100644
--- a/src/pages/Explorer/block.state.ts
+++ b/src/pages/Explorer/block.state.ts
@@ -61,6 +61,7 @@ export interface BlockInfo {
   status: BlockState
   diff: Record<string, [string | null, string | null]> | null
 }
+
 export const [blockInfo$, recordedBlocks$] = partitionByKey(
   client$.pipe(switchMap((client) => client.blocks$)),
   (v) => v.hash,
@@ -117,31 +118,56 @@ export const [blockInfo$, recordedBlocks$] = partitionByKey(
     ),
 )
 
-const getUnpinnedBlockInfo$ = (hash: string): Observable<BlockInfo> => {
-  const throughRpc$ = chainClient$.pipe(
+const getUnpinnedBlockInfo$ = (hash: string): Observable<BlockInfo> =>
+  client$.pipe(
     switchMap((client) =>
-      defer(() =>
-        client.client._request<
-          {
-            block: {
-              extrinsics: HexString[]
-              header: {
-                digest: { logs: Array<unknown> }
-                extrinsicsRoot: string
-                number: HexString
-                parentHash: HexString
-                stateRoot: HexString
-              }
-            }
-          } | null,
-          [string]
-        >("chain_getBlock", [hash]),
-      ).pipe(
-        repeat({
-          delay: 1000,
-        }),
+      from(client.getBlockHeader(hash)).pipe(
+        mergeMap((header) =>
+          combineLatest({
+            hash: of(hash),
+            parent: of(header.parentHash),
+            number: of(header.number),
+            body: client.watchBlockBody(hash),
+            events: from(
+              client.getUnsafeApi().query.System.Events.getValue({
+                at: hash,
+              }),
+            ),
+            header: from(client.getBlockHeader(hash)),
+            status: of(BlockState.Finalized),
+            diff: of(null),
+          }),
+        ),
+        catchError(() => getUnpinnedBlockInfoFallback$(hash, client)),
+        tap((v) => disconnectedBlocks$.next(v)),
       ),
     ),
+  )
+
+const getUnpinnedBlockInfoFallback$ = (
+  hash: string,
+  client: PolkadotClient,
+): Observable<BlockInfo> => {
+  const throughRpc$ = defer(() =>
+    client._request<
+      {
+        block: {
+          extrinsics: HexString[]
+          header: {
+            digest: { logs: Array<unknown> }
+            extrinsicsRoot: string
+            number: HexString
+            parentHash: HexString
+            stateRoot: HexString
+          }
+        }
+      } | null,
+      [string]
+    >("chain_getBlock", [hash]),
+  ).pipe(
+    repeat({
+      delay: 1000,
+    }),
     filter((v) => !!v),
     take(1),
     catchError(() => EMPTY),
@@ -166,7 +192,6 @@ const getUnpinnedBlockInfo$ = (hash: string): Observable<BlockInfo> => {
         diff: null,
       }),
     ),
-    tap((v) => disconnectedBlocks$.next(v)),
   )
 }