move @snort/nostr code into System

packages/app/src/System/RequestMerger.ts

@@ -1,4 +1,4 @@
-import { RawReqFilter } from "@snort/nostr";
+import { RawReqFilter } from "System";
 
 export function mergeSimilar(filters: Array<RawReqFilter>): Array<RawReqFilter> {
   const hasCriticalKeySet = (a: RawReqFilter) => {
@@ -28,3 +28,31 @@ function simpleMerge(filters: Array<RawReqFilter>) {
 
   return result as RawReqFilter;
 }
+
+/**
+ * Check if a filter includes another filter, as in the bigger filter will include the same results as the samller filter
+ * @param bigger
+ * @param smaller
+ * @returns
+ */
+export function filterIncludes(bigger: RawReqFilter, smaller: RawReqFilter) {
+  const outside = bigger as Record<string, Array<string | number> | number>;
+  for (const [k, v] of Object.entries(smaller)) {
+    if (outside[k] === undefined) {
+      return false;
+    }
+    if (Array.isArray(v) && v.some(a => !(outside[k] as Array<string | number>).includes(a))) {
+      return false;
+    }
+    if (typeof v === "number") {
+      if (k === "since" && (outside[k] as number) > v) {
+        return false;
+      }
+      if (k === "until" && (outside[k] as number) < v) {
+        return false;
+      }
+      // limit cannot be checked and is ignored
+    }
+  }
+  return true;
+}