name: Deploy blog immutable package

on:
  workflow_dispatch:
    inputs:
      revision:
        description: Full source commit
        required: true
      artifact_url:
        description: Immutable Gitea generic-package URL
        required: true
      artifact_digest:
        description: sha256 digest of site.tar.gz
        required: true
      target:
        description: Provisioned site-scoped release root
        required: true
      verify_url:
        description: Public release marker URL
        required: true
      desired_commit:
        description: gitops-sandbox commit that selected this release
        required: true
      desired_generation:
        description: Ancestor count of desired_commit; the receiver refuses older selections
        required: true

permissions:
  contents: read

# Best-effort only. Ordering is enforced by the receiver, which applies a
# selection only if its generation is not older than the one already live, so
# a stale dispatch or a re-run of an old run cannot replace a newer release.
concurrency:
  group: blog-deploy
  cancel-in-progress: false

jobs:
  contract:
    runs-on: ubuntu-latest
    container:
      image: git.librete.ch/public/runner-image:v0.2.0@sha256:f60c587d3c0b0aac04a572db5349e27672bf76baec2ce547a3dcc28cebcf1b7e
    timeout-minutes: 5
    steps:
      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262

      - name: Validate dispatch contract without network access
        env:
          REVISION: ${{ inputs.revision }}
          ARTIFACT_URL: ${{ inputs.artifact_url }}
          ARTIFACT_DIGEST: ${{ inputs.artifact_digest }}
          TARGET: ${{ inputs.target }}
          VERIFY_URL: ${{ inputs.verify_url }}
          DESIRED_COMMIT: ${{ inputs.desired_commit }}
          DESIRED_GENERATION: ${{ inputs.desired_generation }}
        run: |
          set -eu
          python3 delivery/scripts/deploy_contract.py validate \
            --revision "$REVISION" \
            --artifact-url "$ARTIFACT_URL" \
            --artifact-digest "$ARTIFACT_DIGEST" \
            --target "$TARGET" \
            --verify-url "$VERIFY_URL" \
            --site-config delivery/site.json \
            --desired-commit "$DESIRED_COMMIT" \
            --desired-generation "$DESIRED_GENERATION"

  deploy:
    needs: contract
    if: ${{ vars.BLOG_STATIC_DEPLOY_ENABLED == 'true' }}
    runs-on: ubuntu-latest
    container:
      image: git.librete.ch/public/runner-image:v0.2.0@sha256:f60c587d3c0b0aac04a572db5349e27672bf76baec2ce547a3dcc28cebcf1b7e
    timeout-minutes: 30
    env:
      ACTIVATION: ${{ vars.BLOG_STATIC_DEPLOY_ENABLED }}
      REVISION: ${{ inputs.revision }}
      ARTIFACT_URL: ${{ inputs.artifact_url }}
      ARTIFACT_DIGEST: ${{ inputs.artifact_digest }}
      TARGET: ${{ inputs.target }}
      VERIFY_URL: ${{ inputs.verify_url }}
      DESIRED_COMMIT: ${{ inputs.desired_commit }}
      DESIRED_GENERATION: ${{ inputs.desired_generation }}
      STATIC_PACKAGE_READ_USER: ${{ secrets.BLOG_PACKAGE_READ_USER }}
      STATIC_PACKAGE_READ_TOKEN: ${{ secrets.BLOG_PACKAGE_READ_TOKEN }}
      STATIC_DEPLOY_HOST: ${{ secrets.BLOG_STATIC_DEPLOY_HOST }}
      STATIC_DEPLOY_USER: ${{ secrets.BLOG_STATIC_DEPLOY_USER }}
      STATIC_DEPLOY_SSH_KEY: ${{ secrets.BLOG_STATIC_DEPLOY_SSH_KEY }}
      STATIC_DEPLOY_KNOWN_HOSTS: ${{ secrets.BLOG_STATIC_DEPLOY_KNOWN_HOSTS }}
    steps:
      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262

      - name: Enforce reviewed deployment gate
        run: |
          set -eu
          test "$ACTIVATION" = true
          python3 delivery/scripts/delivery_gate.py static_deploy \
            --config delivery/.delivery/config.json
          test -n "$STATIC_DEPLOY_HOST"
          test -n "$STATIC_DEPLOY_USER"
          test -n "$STATIC_DEPLOY_SSH_KEY"
          test -n "$STATIC_DEPLOY_KNOWN_HOSTS"
          case "$STATIC_DEPLOY_HOST" in *[!A-Za-z0-9.-]*|'') exit 1;; esac
          case "$STATIC_DEPLOY_USER" in *[!A-Za-z0-9_-]*|'') exit 1;; esac

      - name: Download and inspect the declared immutable artifact
        run: |
          set -eu
          python3 delivery/scripts/deploy_contract.py prepare \
            --revision "$REVISION" \
            --artifact-url "$ARTIFACT_URL" \
            --artifact-digest "$ARTIFACT_DIGEST" \
            --target "$TARGET" \
            --verify-url "$VERIFY_URL" \
            --site-config delivery/site.json \
            --desired-commit "$DESIRED_COMMIT" \
            --desired-generation "$DESIRED_GENERATION" \
            --archive delivery/.build/site.tar.gz \
            --checksum delivery/.build/site.tar.gz.sha256 \
            --request-token delivery/.build/deploy-request.token

      - name: Send the artifact to the site-scoped forced command
        id: receive
        run: |
          set -eu
          umask 077
          mkdir -p "$HOME/.ssh"
          printf '%s\n' "$STATIC_DEPLOY_SSH_KEY" > "$HOME/.ssh/id_static_deploy"
          printf '%s\n' "$STATIC_DEPLOY_KNOWN_HOSTS" > "$HOME/.ssh/known_hosts"
          cat > "$HOME/.ssh/config" <<CONFIG
          Host static-release-target
            HostName $STATIC_DEPLOY_HOST
            User $STATIC_DEPLOY_USER
            IdentityFile $HOME/.ssh/id_static_deploy
            UserKnownHostsFile $HOME/.ssh/known_hosts
            IdentitiesOnly yes
            BatchMode yes
            StrictHostKeyChecking yes
            ConnectTimeout 10
          CONFIG
          request="$(cat delivery/.build/deploy-request.token)"
          status=0
          ssh static-release-target "static-release-receive $request" \
            < delivery/.build/site.tar.gz || status=$?
          # 3: the receiver already applied a newer selection; nothing changed.
          if [ "$status" -eq 3 ]; then
            echo "Superseded: generation $DESIRED_GENERATION ($DESIRED_COMMIT) is older than the live selection; nothing deployed."
            printf 'superseded=true\n' >> "$GITHUB_OUTPUT"
            exit 0
          fi
          test "$status" -eq 0
          printf 'superseded=false\n' >> "$GITHUB_OUTPUT"

      - name: Confirm public revision and digest
        if: ${{ steps.receive.outputs.superseded == 'false' }}
        run: |
          set -eu
          python3 delivery/scripts/static_release.py verify \
            --url "$VERIFY_URL" \
            --revision "$REVISION" \
            --digest "$ARTIFACT_DIGEST"