Add rule count tracking and formatted comment generation for DNS blocklists

index.ts

@@ -35,9 +35,13 @@ Bun.serve({
             rules = rules.concat(listArray)
         }
 
+        const originalRuleCount = rules.length;
+
         rules = Array.from(new Set(rules));
 
-        const rulesText = rules.join('\n');
+        const ruleCount = originalRuleCount - rules.length;
+
+        const rulesText = makeComment(originalRuleCount, ruleCount) + rules.join('\n');
 
         return new Response(rulesText, {
             headers: {
@@ -49,4 +53,26 @@ Bun.serve({
             },
         })
     }
-})
+})
+
+const makeComment = (originalRuleCount: number, ruleCount: number) => {
+    const now = new Date();
+
+    const second = now.getSeconds();
+    const minute = now.getMinutes();
+    const hour = now.getHours();
+    const day = now.getDate();
+    const month = now.getMonth() + 1;
+    const year = now.getFullYear();
+
+    return `[Adblock Plus]
+! Title: HaGeZi's DNS Blocklists Combined
+! Description: A collection of DNS blocklists by HaGeZi, combined into one list, with duplicates removed.
+! Expires: 1 hour
+! Last Modified: ${new Date().toUTCString().split(", ")[1]}
+! Version: ${year}.${month}.${day}.${hour}.${minute}.${second}
+! Syntax: AdBlock
+! Number of Entries: ${ruleCount}
+! Original Number of Entries: ${originalRuleCount}
+! Total Removed Entries: ${originalRuleCount - ruleCount}\n`
+}

test.ts

@@ -156,4 +156,16 @@ const filters = [];
 for (const filter of test.filters) {
     filters.push(filter.url);
 }
-console.log(filters);
+console.log(filters);
+
+// console.log year.month.day.hour.minute.second in 24 hour format
+const now = new Date();
+
+const second = now.getSeconds();
+const minute = now.getMinutes();
+const hour = now.getHours();
+const day = now.getDate();
+const month = now.getMonth() + 1;
+const year = now.getFullYear();
+
+console.log(`${year}.${month}.${day}.${hour}.${minute}.${second}`);