Improve IK-style artifact scanner pipeline

electron/repositories/reviewSamplesRepository.ts

@@ -3,6 +3,9 @@ import path from "node:path";
 import type { ReviewSampleListResult, ReviewSamplesRepositoryPort, ReviewSamplePayload } from "./contracts.js";
 import type { ReviewSampleRecord, SaveResultWithPath } from "../../src/types/global.js";
 
+const SMALL_FILE_LIMIT_BYTES = 8 * 1024 * 1024;
+const TAIL_READ_LIMIT_BYTES = 32 * 1024 * 1024;
+
 export class ReviewSamplesRepository implements ReviewSamplesRepositoryPort {
   private readonly filePath: string;
 
@@ -12,9 +15,12 @@ export class ReviewSamplesRepository implements ReviewSamplesRepositoryPort {
 
   async list(limit = 50): Promise<ReviewSampleListResult> {
     try {
-      const raw = await fs.readFile(this.filePath, "utf8");
-      const lines = raw.split(/\r?\n/).filter(Boolean);
       const safeLimit = Math.max(1, Math.min(200, Number(limit) || 50));
+      const stats = await fs.stat(this.filePath);
+      const raw = stats.size <= SMALL_FILE_LIMIT_BYTES
+        ? await fs.readFile(this.filePath, "utf8")
+        : await readTailText(this.filePath, stats.size, TAIL_READ_LIMIT_BYTES);
+      const lines = raw.split(/\r?\n/).filter(Boolean);
       const samples = lines
         .slice(-safeLimit)
         .map((line) => {
@@ -25,7 +31,8 @@ export class ReviewSamplesRepository implements ReviewSamplesRepositoryPort {
           }
         })
         .filter(Boolean) as ReviewSampleRecord[];
-      return { ok: true, samples: samples.reverse(), total: lines.length, path: this.filePath };
+      const total = stats.size <= SMALL_FILE_LIMIT_BYTES ? lines.length : Math.max(samples.length, lines.length);
+      return { ok: true, samples: samples.reverse(), total, path: this.filePath };
     } catch {
       return { ok: true, samples: [], total: 0, path: this.filePath };
     }
@@ -37,3 +44,17 @@ export class ReviewSamplesRepository implements ReviewSamplesRepositoryPort {
     return { ok: true, path: this.filePath };
   }
 }
+
+async function readTailText(filePath: string, fileSize: number, maxBytes: number) {
+  const bytesToRead = Math.min(fileSize, maxBytes);
+  const handle = await fs.open(filePath, "r");
+  try {
+    const buffer = Buffer.alloc(bytesToRead);
+    await handle.read(buffer, 0, bytesToRead, fileSize - bytesToRead);
+    const text = buffer.toString("utf8");
+    const firstNewline = text.indexOf("\n");
+    return fileSize > bytesToRead && firstNewline >= 0 ? text.slice(firstNewline + 1) : text;
+  } finally {
+    await handle.close();
+  }
+}