#!/usr/bin/env bash
set -xeuo pipefail

main() {
  # Location to persist build metadata between runs (use Actions cache on this). [web:51][web:52]
  BUILD_STATE_DIR="${BUILD_STATE_DIR:-${GITHUB_WORKSPACE:-.}/.build-state}"
  mkdir -p "${BUILD_STATE_DIR}"
  META_FILE="${BUILD_STATE_DIR}/coredns-netboxdns.meta"

  GO_VERSION=$(curl -s 'https://go.dev/VERSION?m=text' | head -n1)
  ACTION_REPO_DIR="${PWD}"
  ACTION_COMMIT="$(git rev-parse HEAD)"

  # 2. Create temp directory
  TMPDIR="$(mktemp -d)"
  echo "Using temp dir: ${TMPDIR}"

  cd "${TMPDIR}"
  mkdir golang
  cd golang
  GOLANG_URL="https://go.dev/dl/${GO_VERSION}.linux-amd64.tar.gz"
  wget "${GOLANG_URL}"
  tar xzf "${GO_VERSION}.linux-amd64.tar.gz"
  PATH="${PATH}:$PWD/go/bin"

  cd "${ACTION_REPO_DIR}"
  go mod edit -go "$(echo "${GO_VERSION}" | sed 's/^go//')"

  # 3. Clone CoreDNS
  cd "${TMPDIR}"
  COREDNS_REPO_URL="https://github.com/coredns/coredns.git"
  COREDNS_DIR="${TMPDIR}/coredns"

  # 4. Checkout coredns to latest release
  git clone --depth=1 --filter=blob:none --tags "${COREDNS_REPO_URL}" "${COREDNS_DIR}"
  cd "${COREDNS_DIR}"
  git fetch --tags
  COREDNS_LATEST_VERSION="$(git tag --list --sort=-version:refname | head -n 1)"
  git fetch --tags --depth=1 origin "${COREDNS_LATEST_VERSION}"
  git checkout "${COREDNS_LATEST_VERSION}"

  echo "CoreDNS version (tag): ${COREDNS_LATEST_VERSION}"
  echo "Action repo commit    : ${ACTION_COMMIT}"

  # 4b. Skip build if same CoreDNS version and same action repo commit as last time.  # NEW
  if [ -f "${META_FILE}" ]; then
    LAST_COREDNS_TAG="$(sed -n 's/^COREDNS_TAG=//p' "${META_FILE}")"
    LAST_ACTION_COMMIT="$(sed -n 's/^ACTION_COMMIT=//p' "${META_FILE}")"

    if [ "${LAST_COREDNS_TAG}" = "${COREDNS_LATEST_VERSION}" ] &&
      [ "${LAST_ACTION_COMMIT}" = "${ACTION_COMMIT}" ]; then
      echo "No changes in CoreDNS version or action repo commit since last build."
      echo "Skipping build and upload."
      exit 0
    fi
  fi

  # 5. Update plugin.cfg to include netboxdns plugin
  #    Insert netboxdns after the 'cache' plugin entry as recommended.
  if ! grep -q '^netboxdns:' plugin.cfg; then
    awk '
      /^cache:/ {
        print
        print "netboxdns:github.com/doubleu-labs/coredns-netbox-plugin-dns"
        next
      }
      { print }
    ' plugin.cfg >plugin.cfg.new
    mv plugin.cfg.new plugin.cfg
  fi

  # 6. Update coredns repo to latest golang version
  # TODO: do we need this? I think we should actually force the plugin to use the coredns configured golang version
  # this possibly only works because coredns is using the latest golang version
  go mod edit -go "$(echo "${GO_VERSION}" | sed 's/^go//')"

  # 7. go mod replace plugin path to the cloned action repo
  #    This assumes the plugin lives at github.com/doubleu-labs/coredns-netbox-plugin-dns in your repo.

  go mod edit -replace=github.com/doubleu-labs/coredns-netbox-plugin-dns="${ACTION_REPO_DIR}"

  # 7. Regenerate plugin source files
  #    CoreDNS uses go generate (via Makefile) to rebuild plugin glue code.

  make gen

  # 9. Compile CoreDNS
  make coredns || make

  # 10. Strip the binary
  STRIP_BIN="${STRIP_BIN:-strip}"
  "${STRIP_BIN}" ./coredns

  # 11. Create a .deb installing /usr/local/bin/coredns
  #     Minimal Debian package using dpkg-deb.
  PKG_ROOT="${TMPDIR}/pkg-root"
  mkdir -p "${PKG_ROOT}/DEBIAN" "${PKG_ROOT}/usr/local/bin"

  # Basic metadata; tweak as needed
  PKG_NAME="coredns-netboxdns"
  PKG_VERSION="$(echo "${COREDNS_LATEST_VERSION}" | sed 's/^v//')"
  PKG_ARCH="$(dpkg --print-architecture 2>/dev/null || echo amd64)"

  cat >"${PKG_ROOT}/DEBIAN/control" <<EOF
Package: ${PKG_NAME}
Version: ${PKG_VERSION}-$(date +%Y%m%d%H%M) 
Section: net
Priority: optional
Architecture: ${PKG_ARCH}
Maintainer: CI <restitux@ohea.xyz>
Description: CoreDNS with netboxdns plugin
 Custom CoreDNS build with netboxdns plugin compiled in.
EOF

  install -m 0755 ./coredns "${PKG_ROOT}/usr/local/bin/coredns"

  DEB_OUT="${TMPDIR}/${PKG_NAME}_${PKG_VERSION}_${PKG_ARCH}.deb"
  dpkg-deb --build "${PKG_ROOT}" "${DEB_OUT}"

  echo "Built Debian package at: ${DEB_OUT}"

  # 12. Upload the package to Gitea Debian registry
  #     Gitea uses HTTP PUT with the .deb in the request body.
  DEB_REGISTRY_URL="https://git.ohea.xyz/api/packages/dns/debian/pool/trixie/main/upload"
  echo "Uploading ${DEB_OUT} to ${DEB_REGISTRY_URL}"
  curl \
    --fail \
    --show-error \
    --silent \
    --request PUT \
    --user "${CI_REGISTRY_USER}:${CI_REGISTRY_PASSWORD}" \
    --upload-file "${DEB_OUT}" \
    "${DEB_REGISTRY_URL}"

  # 13. Store metadata for next run (so it can be used with actions/cache).  # NEW
  cat >"${META_FILE}" <<EOF
COREDNS_TAG=${COREDNS_LATEST_VERSION}
ACTION_COMMIT=${ACTION_COMMIT}
EOF

  echo "Updated build metadata at ${META_FILE}"

}

main "$@"