#!/usr/bin/env python3
"""Refresh the pack's client-side usernamecache.json from the live server cache.

The pack ships <game>/usernamecache.json to clients (via usernamecache.pw.toml)
so Jade can resolve offline-mode owner names client-side (it falls back to
NeoForge's UsernameCache after the Mojang lookup fails). This merges the
server's live cache into packfiles/usernamecache-offline.json and updates the
download hash in usernamecache.pw.toml.

Run after new players have logged in, then refresh/commit/push:

    python3 tools/sync-usernamecache.py
    packwiz refresh
    git add packfiles/usernamecache-offline.json usernamecache.pw.toml index.toml pack.toml
    git commit -m "chore(pack): refresh client usernamecache"
    git push
"""
import hashlib
import json
import pathlib
import re
import sys

ROOT = pathlib.Path(__file__).resolve().parent.parent
LIVE = ROOT / "usernamecache.json"
SHIPPED = ROOT / "packfiles" / "usernamecache-offline.json"
META = ROOT / "usernamecache.pw.toml"


def load(path):
    try:
        return json.loads(path.read_text(encoding="utf-8"))
    except FileNotFoundError:
        return {}


def main():
    live = load(LIVE)
    shipped = load(SHIPPED)
    merged = {**shipped, **live}  # the live server cache wins
    if not merged:
        print("no entries found; is the server's usernamecache.json missing?", file=sys.stderr)
        return 1

    text = json.dumps(merged, indent=2, sort_keys=True) + "\n"
    changed = not SHIPPED.exists() or SHIPPED.read_text(encoding="utf-8") != text
    SHIPPED.parent.mkdir(parents=True, exist_ok=True)
    SHIPPED.write_text(text, encoding="utf-8")

    digest = hashlib.sha256(text.encode("utf-8")).hexdigest()
    meta = META.read_text(encoding="utf-8")
    new_meta = re.sub(r'(?m)^(hash = ")[0-9a-f]+(")$', lambda m: m.group(1) + digest + m.group(2), meta)
    if new_meta != meta:
        META.write_text(new_meta, encoding="utf-8")

    print(f"{len(merged)} entries ({len(live)} live, {len(shipped)} shipped), "
          f"{'updated' if changed else 'unchanged'} -> packfiles/usernamecache-offline.json")
    print(f"sha256 {digest}")
    print("next: packwiz refresh && git add packfiles/usernamecache-offline.json "
          "usernamecache.pw.toml index.toml pack.toml && commit && push")
    return 0


if __name__ == "__main__":
    sys.exit(main())