#!/usr/bin/env bash
# sync-server-mods.sh — mirror the server's mod subset into ./server-mods/.
# Replaces the old render-pack.sh (packwiz). Copies every jar mapped `both` or
# `server` in mods-sides.json from the distribution's forgemods/required dir into
# ./server-mods/, and removes any stray server-mods/*.jar not in the selection
# (authoritative mirror). The minecraft container mounts ./server-mods at /mods
# (REMOVE_OLD_MODS=TRUE), so /data/mods ends up matching exactly.
#
# Cautious by design: halts (non-zero) on a missing mods-sides.json or a selected
# jar absent from the source dir — never a silent partial sync.
#
# Source dir resolution (first match wins):
#   1. CLI arg:  sync-server-mods.sh <forgemods-required-dir-or-dist-root>
#   2. env MODS_DIST_DIR
#   3. $DISTRIBUTION_WEB_ROOT from .env
# The path may point at the dist ROOT (…/distribution[/dist]) or directly at
# …/servers/ulicraft-1.21.1/forgemods/required — both are accepted.
set -euo pipefail

cd "$(dirname "$0")/.."   # repo root

[ -f .env ] && { set -a; . ./.env; set +a; }

REQUIRED_SUBPATH="servers/ulicraft-1.21.1/forgemods/required"
SIDES_JSON="mods-sides.json"
DEST="server-mods"

# ── Resolve source dir ──────────────────────────────────────────────
if [ "${1:-}" != "" ]; then
  SRC="$1"; ORIGIN="CLI arg"
elif [ "${MODS_DIST_DIR:-}" != "" ]; then
  SRC="$MODS_DIST_DIR"; ORIGIN="MODS_DIST_DIR env"
elif [ "${DISTRIBUTION_WEB_ROOT:-}" != "" ]; then
  SRC="$DISTRIBUTION_WEB_ROOT"; ORIGIN="\$DISTRIBUTION_WEB_ROOT"
else
  echo "no source dir: pass a path, set MODS_DIST_DIR, or DISTRIBUTION_WEB_ROOT in .env" >&2
  exit 1
fi

if [ -d "$SRC/$REQUIRED_SUBPATH" ]; then
  REQ="$SRC/$REQUIRED_SUBPATH"
elif [ "$(basename "$SRC")" = "required" ] && [ -d "$SRC" ]; then
  REQ="$SRC"
else
  echo "forgemods/required dir not found (from $ORIGIN=$SRC)" >&2
  echo "tried: $SRC/$REQUIRED_SUBPATH  and  $SRC" >&2
  exit 1
fi

[ -f "$SIDES_JSON" ] || { echo "$SIDES_JSON not found — run tooling/classify-mods.py first" >&2; exit 1; }

# ── Selected jars (both|server) ─────────────────────────────────────
select_jars() {
  if command -v jq >/dev/null 2>&1; then
    jq -r 'to_entries[] | select(.value == "both" or .value == "server") | .key' "$SIDES_JSON"
  else
    python3 - "$SIDES_JSON" <<'PY'
import json, sys
with open(sys.argv[1], encoding="utf-8") as fh:
    sides = json.load(fh)
for name, side in sides.items():
    if side in ("both", "server"):
        print(name)
PY
  fi
}

mapfile -t SELECTED < <(select_jars | sort)
[ "${#SELECTED[@]}" -gt 0 ] || { echo "no jars selected (both/server) in $SIDES_JSON — nothing to sync" >&2; exit 1; }

# ── Halt if any selected jar is missing from the source ─────────────
missing=()
for jar in "${SELECTED[@]}"; do
  [ -f "$REQ/$jar" ] || missing+=("$jar")
done
if [ "${#missing[@]}" -gt 0 ]; then
  echo "ERROR: ${#missing[@]} selected jar(s) missing from source ($REQ):" >&2
  printf '  %s\n' "${missing[@]}" >&2
  echo "refusing to do a partial sync — fix mods-sides.json or the distribution." >&2
  exit 1
fi

# ── Mirror: copy selected, prune everything else ────────────────────
mkdir -p "$DEST"

# Prune stray jars not in the current selection.
declare -A keep
for jar in "${SELECTED[@]}"; do keep["$jar"]=1; done
pruned=0
shopt -s nullglob
for existing in "$DEST"/*.jar; do
  base="$(basename "$existing")"
  if [ -z "${keep[$base]:-}" ]; then
    rm -f -- "$existing"
    pruned=$((pruned + 1))
  fi
done
shopt -u nullglob

# Copy selection (cp -p preserves mtime so unchanged jars don't re-touch).
copied=0
for jar in "${SELECTED[@]}"; do
  cp -p -- "$REQ/$jar" "$DEST/$jar"
  copied=$((copied + 1))
done

echo "source: $REQ  (from $ORIGIN)"
echo "synced $copied jar(s) into $DEST/ (pruned $pruned stray)."