name: Release

on:
  push:
    tags:
      - 'v*'

jobs:
  # Deliberately does NOT rebuild or re-run lint/typecheck/test/build: the
  # image for this exact commit was already built and pushed by ci.yml's
  # build-image job when it landed on main (which itself only runs after
  # the `test` job passes). This job just promotes that already-verified
  # image to the release tag + `latest` and deploys it — if the tagged
  # commit was never pushed to main (or CI hasn't finished yet), the
  # "Pull the tested image" step below fails loudly instead of silently
  # rebuilding from source and skipping the checks.
  promote-and-deploy:
    runs-on: ubuntu-latest
    # Node-based image (not the bare runner, not a Docker-only image) for
    # the same reasons as ci.yml's build-image job: the runner needs a
    # Docker CLI added via apt (it has none of its own), and actions/checkout
    # needs a Node runtime that a plain docker:*-cli image doesn't have.
    container:
      image: node:22-bookworm-slim
    steps:
      - name: Install Docker CLI and ssh client
        run: |
          apt-get update
          apt-get install -y --no-install-recommends docker.io openssh-client
          rm -rf /var/lib/apt/lists/*

      - name: Determine image tags
        id: image
        # Gitea Actions' runner is protocol-compatible with GitHub Actions,
        # so step commands use the same $GITHUB_OUTPUT / $GITHUB_ENV
        # mechanism (the `gitea.*` vs `github.*` expression contexts are
        # just aliases of each other for `${{ }}` templating).
        #
        # The tag name (github.ref_name / $GITHUB_REF_NAME) is
        # attacker-influenced: anyone with tag-push rights controls it, and
        # git allows shell metacharacters in tag names. It's read here via
        # the automatic $GITHUB_REF_NAME env var rather than `${{ github.ref_name }}`
        # so its value reaches bash as data (argv/envp), never spliced into
        # the script text — `${{ }}` expressions are substituted into the
        # YAML before bash ever sees the script, which is what makes
        # interpolating attacker-controlled values that way a script-injection
        # vector (arbitrary code execution in a job that holds the registry
        # and production deploy credentials).
        run: |
          echo "registry=${REGISTRY:-git.maro.run}" >> "$GITHUB_OUTPUT"
          echo "repo=${REGISTRY_REPO:-maro/anouma}" >> "$GITHUB_OUTPUT"
          echo "version=$GITHUB_REF_NAME" >> "$GITHUB_OUTPUT"
        env:
          REGISTRY: git.maro.run
          REGISTRY_REPO: maro/anouma

      - name: Log in to registry
        env:
          REGISTRY_IMAGE: ${{ steps.image.outputs.registry }}
          REGISTRY_USERNAME: ${{ secrets.REGISTRY_USERNAME }}
          REGISTRY_PASSWORD: ${{ secrets.REGISTRY_PASSWORD }}
        run: echo "$REGISTRY_PASSWORD" | docker login "$REGISTRY_IMAGE" -u "$REGISTRY_USERNAME" --password-stdin

      - name: Pull the tested image for this commit
        env:
          IMAGE: ${{ steps.image.outputs.registry }}/${{ steps.image.outputs.repo }}
        run: |
          docker pull "$IMAGE:$GITHUB_SHA" || {
            echo "::error::No image found for commit $GITHUB_SHA. This tag must point at a commit that was already pushed to main and built by ci.yml's build-image job — push to main first (and wait for CI to finish) before tagging a release." >&2
            exit 1
          }

      - name: Promote image to the release tag and latest
        env:
          IMAGE: ${{ steps.image.outputs.registry }}/${{ steps.image.outputs.repo }}
          VERSION: ${{ steps.image.outputs.version }}
        run: |
          docker tag "$IMAGE:$GITHUB_SHA" "$IMAGE:$VERSION"
          docker tag "$IMAGE:$GITHUB_SHA" "$IMAGE:latest"

      - name: Push promoted tags
        env:
          IMAGE: ${{ steps.image.outputs.registry }}/${{ steps.image.outputs.repo }}
          VERSION: ${{ steps.image.outputs.version }}
        run: |
          docker push "$IMAGE:$VERSION"
          docker push "$IMAGE:latest"

      - name: Deploy to production
        env:
          DEPLOY_HOST: ${{ secrets.DEPLOY_HOST }}
          DEPLOY_PORT: ${{ secrets.DEPLOY_PORT }}
          DEPLOY_USER: ${{ secrets.DEPLOY_USER }}
          DEPLOY_SSH_KEY: ${{ secrets.DEPLOY_SSH_KEY }}
          # Optional: pin the exact host key instead of trusting it on
          # first connect (see DEPLOYMENT.md). Safe to leave unset.
          DEPLOY_HOST_KEY: ${{ secrets.DEPLOY_HOST_KEY }}
          VERSION: ${{ steps.image.outputs.version }}
        shell: bash
        run: |
          set -euo pipefail
          umask 077
          key_file="$(mktemp)"
          known_hosts_file="$(mktemp)"
          trap 'rm -f "$key_file" "$known_hosts_file"' EXIT

          printf '%s\n' "$DEPLOY_SSH_KEY" > "$key_file"
          chmod 600 "$key_file"

          if [ -n "${DEPLOY_HOST_KEY:-}" ]; then
            printf '%s\n' "$DEPLOY_HOST_KEY" > "$known_hosts_file"
          else
            ssh-keyscan -p "${DEPLOY_PORT:-22}" "$DEPLOY_HOST" > "$known_hosts_file" 2>/dev/null
          fi

          # The forced command in the server's authorized_keys (see
          # setup.sh) ignores this and always runs deploy.sh itself — the
          # string below only ever reaches it via $SSH_ORIGINAL_COMMAND.
          ssh -i "$key_file" -o UserKnownHostsFile="$known_hosts_file" -p "${DEPLOY_PORT:-22}" \
            "${DEPLOY_USER}@${DEPLOY_HOST}" "deploy ${VERSION}"