From 4fb9bb75633decb6e0428e9091cfaaad82c0db3e Mon Sep 17 00:00:00 2001
From: DecDuck <declanahofmeyr@gmail.com>
Date: Fri, 15 Aug 2025 16:49:18 +1000
Subject: [PATCH] fix: manifest sizing for slow backends

---
 __test__/debug.spec.mjs | 22 ++++++++++++++++++++
 __test__/utils.spec.mjs | 28 +++++++++++++++++++++++--
 package.json            |  2 +-
 src/manifest.rs         | 46 ++++++++++++++++++++++++++++-------------
 4 files changed, 81 insertions(+), 17 deletions(-)
 create mode 100644 __test__/debug.spec.mjs

diff --git a/__test__/debug.spec.mjs b/__test__/debug.spec.mjs
new file mode 100644
index 0000000..5df0565
--- /dev/null
+++ b/__test__/debug.spec.mjs
@@ -0,0 +1,22 @@
+import test from "ava";
+import { DropletHandler, generateManifest } from "../index.js";
+
+test.skip("debug", async (t) => {
+  const handler = new DropletHandler();
+
+  console.log("created handler");
+
+  const manifest = JSON.parse(
+    await new Promise((r, e) =>
+      generateManifest(
+        handler,
+        "./assets/TheGame.zip",
+        (_, __) => {},
+        (_, __) => {},
+        (err, manifest) => (err ? e(err) : r(manifest))
+      )
+    )
+  );
+
+  return t.pass();
+});
diff --git a/__test__/utils.spec.mjs b/__test__/utils.spec.mjs
index eb30ca1..890b4c1 100644
--- a/__test__/utils.spec.mjs
+++ b/__test__/utils.spec.mjs
@@ -102,7 +102,7 @@ test("read file offset", async (t) => {
   fs.rmSync(dirName, { recursive: true });
 });
 
-test("zip speed test", async (t) => {
+test.skip("zip speed test", async (t) => {
   t.timeout(100_000_000);
   const dropletHandler = new DropletHandler();
 
@@ -135,7 +135,31 @@ test("zip speed test", async (t) => {
 
   const roughAverage = totalRead / totalSeconds;
 
-  console.log(`total rough average: ${prettyBytes(roughAverage)}/s`)
+  console.log(`total rough average: ${prettyBytes(roughAverage)}/s`);
+
+  t.pass();
+});
+
+test("zip manifest test", async (t) => {
+  const dropletHandler = new DropletHandler();
+  const manifest = JSON.parse(
+    await new Promise((r, e) =>
+      generateManifest(
+        dropletHandler,
+        "./assets/TheGame.zip",
+        (_, __) => {},
+        (_, __) => {},
+        (err, manifest) => (err ? e(err) : r(manifest))
+      )
+    )
+  );
+
+  const file = manifest[Object.keys(manifest).at(0)];
+  const amount = file.ids.length;
+
+  if(amount > 20) {
+    return t.fail(`Zip manifest has ${amount} chunks, more than 20`);
+  }
 
   t.pass();
 });
diff --git a/package.json b/package.json
index 269ed27..e1e5af4 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@drop-oss/droplet",
-  "version": "2.0.2",
+  "version": "2.1.0",
   "main": "index.js",
   "types": "index.d.ts",
   "napi": {
diff --git a/src/manifest.rs b/src/manifest.rs
index ef6049a..9b3b68a 100644
--- a/src/manifest.rs
+++ b/src/manifest.rs
@@ -1,7 +1,6 @@
 use std::{
   collections::HashMap,
   io::{BufRead, BufReader},
-  path::Path,
   sync::Arc,
   thread,
 };
@@ -42,11 +41,11 @@ pub fn generate_manifest<'a>(
   log_sfn: ThreadsafeFunction<String>,
   callback_sfn: ThreadsafeFunction<String>,
 ) -> Result<()> {
-  let backend: &mut Box<dyn VersionBackend + Send> =
-    droplet_handler.create_backend_for_path(dir).ok_or(napi::Error::from_reason("Could not create backend for path."))?;
-  let backend: &'static mut Box<dyn VersionBackend + Send> =
-    unsafe { std::mem::transmute(backend) };
-  thread::spawn(move || {
+  let backend: &mut Box<dyn VersionBackend + Send> = droplet_handler
+    .create_backend_for_path(dir)
+    .ok_or(napi::Error::from_reason(
+    "Could not create backend for path.",
+  ))?;
     let files = backend.list_files();
 
     // Filepath to chunk data
@@ -56,8 +55,8 @@ pub fn generate_manifest<'a>(
     let mut i: i32 = 0;
 
     for version_file in files {
-      let raw_reader = backend.reader(&version_file).unwrap();
-      let mut reader = BufReader::with_capacity(CHUNK_SIZE, raw_reader);
+      let reader = backend.reader(&version_file).unwrap();
+      let mut reader = BufReader::with_capacity(8128, reader);
 
       let mut chunk_data = ChunkData {
         permissions: version_file.permission,
@@ -68,12 +67,28 @@ pub fn generate_manifest<'a>(
 
       let mut chunk_index = 0;
       loop {
+        let mut length = 0;
         let mut buffer: Vec<u8> = Vec::new();
-        reader.fill_buf().unwrap().clone_into(&mut buffer);
-        let length = buffer.len();
+        let mut file_empty = false;
 
-        if length == 0 {
-          break;
+        loop {
+          let read_buf = reader.fill_buf().unwrap();
+          let buf_length = read_buf.len();
+
+          length += buf_length;
+
+          if length >= CHUNK_SIZE {
+            break;
+          }
+
+          // If we're out of data, add this chunk and then move onto the next file
+          if buf_length == 0 {
+            file_empty = true;
+            break;
+          }
+
+          buffer.extend_from_slice(read_buf);
+          reader.consume(length);
         }
 
         let chunk_id = Uuid::new_v4();
@@ -88,10 +103,14 @@ pub fn generate_manifest<'a>(
           "Processed chunk {} for {}",
           chunk_index, &version_file.relative_filename
         );
+
         log_sfn.call(Ok(log_str), ThreadsafeFunctionCallMode::Blocking);
 
-        reader.consume(length);
         chunk_index += 1;
+
+        if file_empty {
+          break;
+        }
       }
 
       chunks.insert(version_file.relative_filename, chunk_data);
@@ -105,7 +124,6 @@ pub fn generate_manifest<'a>(
       Ok(json!(chunks).to_string()),
       ThreadsafeFunctionCallMode::Blocking,
     );
-  });
 
   Ok(())
 }