#!/usr/bin/env bash

set -euo pipefail

readonly SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
readonly REPO_ROOT="$(cd "${SCRIPT_DIR}/.." && pwd)"
readonly MANIFEST_PATH="${REPO_ROOT}/scripts/skill-bundles.json"
BUILD_DIR=""

usage() {
  cat <<'EOF'
Usage:
  package_skill_runtimes.sh plan
  package_skill_runtimes.sh validate
  package_skill_runtimes.sh package

The bundle manifest is package-oriented. Bundles in state=planned are skipped by
the package command until their package-owned entrypoints exist.
EOF
}

require_command() {
  local cmd="$1"
  if ! command -v "${cmd}" >/dev/null 2>&1; then
    printf 'missing required command: %s\n' "${cmd}" >&2
    exit 1
  fi
}

emit_bundles() {
  node -e '
    const fs = require("node:fs");
    const manifestPath = process.argv[1];
    const manifest = JSON.parse(fs.readFileSync(manifestPath, "utf8"));
    for (const bundle of manifest.bundles ?? []) {
      const row = [
        bundle.skill,
        bundle.type,
        bundle.runtimePackage,
        bundle.entrypoint,
        bundle.output,
        bundle.buildState
      ].join("\t");
      process.stdout.write(`${row}\n`);
    }
  ' "${MANIFEST_PATH}"
}

cleanup() {
  if [[ -n "${BUILD_DIR}" && -d "${BUILD_DIR}" ]]; then
    rm -rf "${BUILD_DIR}"
  fi
}

plan() {
  printf 'skill bundle plan from %s\n' "${MANIFEST_PATH}"
  while IFS=$'\t' read -r skill type runtime_package entrypoint output build_state; do
    printf -- '- skill=%s type=%s state=%s runtime=%s entrypoint=%s output=%s\n' \
      "${skill}" "${type}" "${build_state}" "${runtime_package}" "${entrypoint}" "${output}"
  done < <(emit_bundles)
}

validate() {
  local failures=0

  while IFS=$'\t' read -r skill type runtime_package entrypoint output build_state; do
    local runtime_path="${REPO_ROOT}/${runtime_package#./}"
    local entrypoint_path="${REPO_ROOT}/${entrypoint#./}"
    local output_path="${REPO_ROOT}/${output}"

    if [[ "${type}" != "go-binary" ]]; then
      printf 'invalid bundle type for %s: %s\n' "${skill}" "${type}" >&2
      failures=1
    fi

    if [[ ! -d "${runtime_path}" ]]; then
      printf 'missing runtime package dir for %s: %s\n' "${skill}" "${runtime_package}" >&2
      failures=1
    fi

    if [[ ! -f "${runtime_path}/go.mod" ]]; then
      printf 'missing go.mod for %s runtime package: %s\n' "${skill}" "${runtime_package}" >&2
      failures=1
    fi

    if [[ "${build_state}" != "planned" && ! -d "${entrypoint_path}" ]]; then
      printf 'missing ready entrypoint for %s: %s\n' "${skill}" "${entrypoint}" >&2
      failures=1
    fi

    if [[ "${output}" != skills/* ]]; then
      printf 'output for %s must stay under skills/: %s\n' "${skill}" "${output}" >&2
      failures=1
    fi

    if [[ "${build_state}" != "planned" && ! -d "$(dirname "${output_path}")" ]]; then
      printf 'missing output parent for %s: %s\n' "${skill}" "$(dirname "${output}")" >&2
      failures=1
    fi
  done < <(emit_bundles)

  if [[ "${failures}" -ne 0 ]]; then
    exit 1
  fi

  printf 'skill bundle manifest validated\n'
}

package_bundles() {
  validate

  require_command go
  require_command install
  require_command mktemp

  BUILD_DIR="$(mktemp -d "${TMPDIR:-/tmp}/skill-runtimes.XXXXXX")"
  trap cleanup EXIT INT TERM

  while IFS=$'\t' read -r skill type runtime_package entrypoint output build_state; do
    if [[ "${build_state}" != "ready" ]]; then
      printf 'skipping %s (%s)\n' "${skill}" "${build_state}"
      continue
    fi

    local output_path="${REPO_ROOT}/${output}"
    local artifact_path="${BUILD_DIR}/${skill}"

    printf 'building %s from %s\n' "${skill}" "${entrypoint}"
    (
      cd "${REPO_ROOT}"
      go build -trimpath -o "${artifact_path}" "${entrypoint}"
    )

    mkdir -p "$(dirname "${output_path}")"
    install -m 0755 "${artifact_path}" "${output_path}"
    printf 'installed %s\n' "${output}"
  done < <(emit_bundles)
}

main() {
  require_command node

  local command="${1:-}"
  case "${command}" in
    plan)
      plan
      ;;
    validate)
      validate
      ;;
    package)
      package_bundles
      ;;
    ""|-h|--help|help)
      usage
      ;;
    *)
      printf 'unknown command: %s\n' "${command}" >&2
      usage >&2
      exit 1
      ;;
  esac
}

main "$@"