#!/usr/bin/env bash
# Shared helpers for building custom mods from manifests.
# Expected layout:
#   mods/<name>/manifest.sh   -> source the manifest (defines MOD_NAME, SOURCE_URL, ...)
#   scripts/lib.sh            -> this file
#   out/<name>/               -> built jars

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
REPO_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
MODS_DIR="$REPO_ROOT/mods"
OUT_DIR="$REPO_ROOT/out"
WORK_DIR="$REPO_ROOT/build"

require_manifest() {
  local name="$1"
  local manifest="$MODS_DIR/$name/manifest.sh"
  if [[ ! -f "$manifest" ]]; then
    echo "ERROR: no manifest at $manifest" >&2
    return 1
  fi
}

load_manifest() {
  local name="$1"
  require_manifest "$name"
  # shellcheck disable=SC1090
  source "$MODS_DIR/$name/manifest.sh"
  : "${MOD_NAME:?manifest must set MOD_NAME}"
  : "${SOURCE_URL:?manifest must set SOURCE_URL}"
  : "${BUILD_CMD:?manifest must set BUILD_CMD}"
  : "${JAR_GLOB:?manifest must set JAR_GLOB}"
  : "${LICENSE:?manifest must set LICENSE}"
}

list_manifests() {
  for d in "$MODS_DIR"/*/; do
    [[ -d "$d" ]] || continue
    basename "$d"
  done
}

check_jdk() {
  local ver
  ver="$(java -version 2>&1 | awk -F'"' '/version/ {print $2; exit}')"
  case "$ver" in
    21*)
      return 0
      ;;
  esac
  # Not on JDK 21: try to switch to a local JDK 21 install so the build uses
  # the right toolchain for NeoForge 1.21.1 mods.
  for jdk in /usr/lib/jvm/java-21-openjdk /usr/lib/jvm/java-21*; do
    if [[ -x "$jdk/bin/java" ]]; then
      export JAVA_HOME="$jdk"
      export PATH="$jdk/bin:$PATH"
      echo "Using JDK 21 at $jdk"
      return 0
    fi
  done
  echo "WARNING: JDK $ver detected and no JDK 21 found; NeoForge 1.21.1 mods are built with JDK 21." >&2
}