name: Release

"on":
  push:
    tags:
      - "**"

permissions:
  contents: write
  releases: write

jobs:
  release:
    runs-on: ubuntu-latest
    if: startsWith(github.ref, 'refs/tags/')

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Extract changelog and update CHANGELOG.md
        id: changelog
        env:
          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
        shell: bash
        run: |
          set -euo pipefail

          current_tag="${GITHUB_REF_NAME}"
          today=$(date +%Y-%m-%d)

          # Extract content of [Unreleased] section (non-empty lines)
          release_notes=$(awk '/^## \[Unreleased\]/{found=1; next} found && /^## \[/{exit} found{print}' CHANGELOG.md | sed '/^[[:space:]]*$/d')

          if [ -z "${release_notes}" ]; then
            release_notes="Voir les commits pour le détail des changements."
          fi

          printf '%s\n' "${release_notes}" > release_notes.md

          # For stable releases: rename [Unreleased] and insert a new empty section
          case "${current_tag}" in
            *-rc*|*-beta*|*-alpha*)
              echo "Pre-release tag — CHANGELOG.md non modifié"
              ;;
            *)
              # Rename [Unreleased] → version header
              sed -i "s/^## \[Unreleased\]$/## [${current_tag}] — ${today}/" CHANGELOG.md

              # Insert new empty [Unreleased] section after "# Changelog"
              sed -i "s/^# Changelog$/# Changelog\n\n## [Unreleased]/" CHANGELOG.md

              # Insert reference link before the first existing [vX...] link
              awk -v tag="${current_tag}" -v url="${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}/releases/tag/${current_tag}" '
                !inserted && /^\[v/ { print "[" tag "]: " url; inserted=1 }
                { print }
              ' CHANGELOG.md > CHANGELOG.tmp && mv CHANGELOG.tmp CHANGELOG.md

              git config user.name "CI"
              git config user.email "ci@forge.lclr.dev"
              scheme="${GITHUB_SERVER_URL%%://*}"
              host="${GITHUB_SERVER_URL#*://}"
              git remote set-url origin "${scheme}://x-token:${GITEA_TOKEN}@${host}/${GITHUB_REPOSITORY}.git"
              git add CHANGELOG.md
              git commit -m "chore(changelog): release ${current_tag}"
              git push origin HEAD:main
              ;;
          esac

      - name: Create or update release
        env:
          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
        shell: bash
        run: |
          set -euo pipefail

          current_tag="${GITHUB_REF_NAME}"
          api_url="${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/releases"
          release_by_tag_url="${api_url}/tags/${current_tag}"
          prerelease=false

          case "${current_tag}" in
            *-rc*|*-beta*|*-alpha*)
              prerelease=true
              ;;
          esac

          # Build commit log since previous stable tag
          previous_stable_tag=""
          if previous_stable_tag="$(
            git describe --tags --abbrev=0 \
              --exclude '*-rc*' \
              --exclude '*-beta*' \
              --exclude '*-alpha*' \
              "${current_tag}^" 2>/dev/null
          )"; then
            range="${previous_stable_tag}..${current_tag}"
          else
            range="${current_tag}"
          fi

          {
            cat release_notes.md
            printf '\n\n## Commits\n\n'
            git log --reverse --pretty=format:'- %h %s' "${range}"
            printf '\n'
          } > release_body.md

          json_escape() {
            sed ':a;N;$!ba;s/\\/\\\\/g;s/"/\\"/g;s/\t/\\t/g;s/\r//g;s/\n/\\n/g'
          }

          body="$(json_escape < release_body.md)"
          payload="$(printf '{"tag_name":"%s","name":"%s","body":"%s","draft":false,"prerelease":%s}' \
            "${current_tag}" \
            "${current_tag}" \
            "${body}" \
            "${prerelease}")"

          http_code="$(
            curl --silent --show-error --output release.json --write-out '%{http_code}' \
              --header "Authorization: token ${GITEA_TOKEN}" \
              --header 'Accept: application/json' \
              "${release_by_tag_url}"
          )"

          case "${http_code}" in
            200)
              release_id="$(
                tr '{,' '\n' < release.json |
                  sed -n 's/^[[:space:]]*"id":[[:space:]]*\([0-9][0-9]*\)$/\1/p' |
                  head -n1
              )"

              if [ -z "${release_id}" ]; then
                echo "failed to parse release id from existing release response" >&2
                exit 1
              fi

              curl --silent --show-error --fail \
                --request PATCH \
                --header "Authorization: token ${GITEA_TOKEN}" \
                --header 'Accept: application/json' \
                --header 'Content-Type: application/json' \
                --data "${payload}" \
                "${api_url}/${release_id}" >/dev/null
              ;;
            404)
              curl --silent --show-error --fail \
                --request POST \
                --header "Authorization: token ${GITEA_TOKEN}" \
                --header 'Accept: application/json' \
                --header 'Content-Type: application/json' \
                --data "${payload}" \
                "${api_url}" >/dev/null
              ;;
            *)
              echo "unexpected status code while looking up release: ${http_code}" >&2
              cat release.json >&2
              exit 1
              ;;
          esac