Phase 9: the private pack to hand out

build/...-private.mrpack lists every mod by download link, CurseForge-only ones
included, with the credits and non-affiliation notice inside and no third-party jar.
tools/check_private_pack.py downloads all of it and checks the hashes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tools/check_private_pack.py

@@ -0,0 +1,70 @@
+#!/usr/bin/env python3
+"""Check the private pack as a launcher would install it: every link really downloads the pinned file, every mod of the
+pack is listed exactly once with the right side, and no third-party jar sits inside.
+
+Downloads each file fresh, so it needs the network and takes a minute or two.
+
+Usage: tools/check_private_pack.py
+"""
+import hashlib
+import json
+import sys
+import tomllib
+import urllib.request
+import zipfile
+from pathlib import Path, PurePosixPath
+
+import lock
+
+ROOT = lock.ROOT
+PACK = ROOT / "pack"
+
+
+def main():
+    version = tomllib.loads((PACK / "pack.toml").read_text())["version"]
+    archive = ROOT / f"build/cobblemon-survival-pack-{version}-private.mrpack"
+    if not archive.exists():
+        sys.exit(f"{archive} is missing: run tools/build.py first")
+    problems = []
+    with zipfile.ZipFile(archive) as z:
+        names = z.namelist()
+        index = json.loads(z.read("modrinth.index.json"))
+    jars = [n for n in names if n.endswith(".jar")]
+    if [PurePosixPath(n).name for n in jars] != ["cobblesurvival-0.0.1.jar"]:
+        problems.append(f"jars inside the pack: {jars}")
+    if "overrides/CREDITS.md" not in names:
+        problems.append("no credits in the pack")
+    entries = {PurePosixPath(e["path"]).name: e for e in index["files"]}
+    if len(entries) != len(index["files"]):
+        problems.append("a file is listed twice")
+    metas = [tomllib.loads(p.read_text()) for p in sorted([*(PACK / "mods").glob("*.pw.toml"), *(PACK / "shaderpacks").glob("*.pw.toml")])]
+    wanted = {m["filename"]: m for m in metas}
+    if set(wanted) != set(entries):
+        problems.append(f"missing {sorted(set(wanted) - set(entries))}, unexpected {sorted(set(entries) - set(wanted))}")
+    total = 0
+    for name, entry in sorted(entries.items()):
+        request = urllib.request.Request(entry["downloads"][0], headers={"User-Agent": "cobblemon-survival-pack check"})
+        try:
+            with urllib.request.urlopen(request, timeout=300) as response:
+                content = response.read()
+        except OSError as e:
+            problems.append(f"{name}: {e}")
+            continue
+        total += len(content)
+        if hashlib.sha512(content).hexdigest() != entry["hashes"]["sha512"] or hashlib.sha1(content).hexdigest() != entry["hashes"]["sha1"]:
+            problems.append(f"{name}: the download doesn't match its hash")
+        if len(content) != entry["fileSize"]:
+            problems.append(f"{name}: size {len(content)}, listed {entry['fileSize']}")
+        side = wanted.get(name, {}).get("side", "both")
+        expected = {"client": side != "server", "server": side != "client"}
+        if {k: v == "required" for k, v in entry["env"].items()} != expected:
+            problems.append(f"{name}: env {entry['env']} but side {side}")
+    print(f"{len(entries)} files, {total / 1e6:.0f} MB downloaded and checked; {archive.name} is {archive.stat().st_size / 1e6:.1f} MB")
+    if problems:
+        print("\n".join(f"  - {p}" for p in problems))
+        sys.exit("PRIVATE PACK CHECK FAILED")
+    print("PRIVATE PACK CHECK PASSED")
+
+
+if __name__ == "__main__":
+    main()