# Supply-chain gate (task 46). Coordinates with task 42's `ci.yml`.
#
# Per-PR legs: `manifest-lint` (kustomize build + scripts/check_manifests.py,
# including the L7-vs-L4 mTLS pairing check).
# Per-push-to-master legs: the image is built per-arch on native runners
# (`build` matrix: linux/amd64 on ubuntu-24.04, linux/arm64 on ubuntu-24.04-arm,
# no QEMU), each pushed by digest with SBOM + provenance; the `merge` job then
# assembles the multi-arch manifest (`imagetools create`), publishes it under
# the mutable `latest` tag, scans it (trivy/grype gate HIGH/CRITICAL, syft SBOM
# artifact), keyless-signs the index with cosign, and `pin-digest` writes the
# index digest into `deploy/k8s/kustomization.yaml` (strict lint re-run).
# Release tags (`v*`): the merged multi-arch image is published under semver
# tags (X.Y.Z, X.Y, X, `latest`; a pre-release tag gets only X.Y.Z) and a GitHub
# Release is created. `pin-digest` does not run on a tag (it tracks master).
# No `sha-<commit>` tag is published: a master push only moves `latest`, and
# GHCR keeps the superseded (now-untagged) manifests until they are pruned.
# Scheduled legs (weekly rebuild, Monday 04:00 UTC): rebuild + rescan + resign
# so base-image digests advance even without code changes.
#
# The L7 mTLS constraint is DOCUMENTED (docs/DEPLOYMENT.md) and lint-checked
# here; it is explicitly NOT exercised end-to-end in CI.

name: supply-chain

on:
  push:
    branches: ["master"]
    tags: ["v*"]
  pull_request: {}
  schedule:
    # Weekly rebuild (Monday 04:00 UTC).
    - cron: "0 4 * * 1"
  workflow_dispatch: {}

permissions:
  contents: read

env:
  REGISTRY_IMAGE: ghcr.io/syavne/d-oauth-server
  SQLX_OFFLINE: "true"

jobs:
  manifest-lint:
    name: manifest-lint
    runs-on: ubuntu-24.04
    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
      - uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
        with:
          python-version: "3.x"
      - name: Install pyyaml + kustomize
        run: |
          pip install pyyaml
          curl -sSfL https://github.com/kubernetes-sigs/kustomize/releases/download/kustomize%2Fv5.8.3/kustomize_v5.8.3_linux_amd64.tar.gz \
            | tar -xzf - kustomize && sudo mv kustomize /usr/local/bin/
      - name: Kustomize build
        run: kustomize build deploy/k8s
      - name: Manifest policy lint (probes, PDB, no-baked-secrets, L7-vs-L4 mTLS)
        run: python3 scripts/check_manifests.py

  build:
    name: build (${{ matrix.arch }})
    if: github.event_name == 'push' || github.event_name == 'schedule' || github.event_name == 'workflow_dispatch'
    strategy:
      fail-fast: false
      matrix:
        include:
          - runner: ubuntu-24.04
            platform: linux/amd64
            arch: amd64
          - runner: ubuntu-24.04-arm
            platform: linux/arm64
            arch: arm64
    runs-on: ${{ matrix.runner }}
    permissions:
      contents: read
      packages: write
      id-token: write
    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
      - uses: docker/setup-buildx-action@f87e5991a6d7451dcb8d9637bfbc97413f497069 # v4.4.1
      - uses: docker/login-action@dbcb813823bdd20940b903addbd779551569679f # v4.6.0
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}
      - name: Build ${{ matrix.arch }} natively and push by digest
        id: bake
        run: |
          set -euo pipefail
          IMAGE_TAGS="${REGISTRY_IMAGE}" docker buildx bake image \
            --set "image.platform=${{ matrix.platform }}" \
            --set "image.output=type=image,push=true,push-by-digest=true,name-canonical=true" \
            --sbom=true \
            --provenance=mode=max \
            --metadata-file /tmp/bake-metadata.json
          digest=$(python3 -c "
          import json
          meta = json.load(open('/tmp/bake-metadata.json'))
          print(meta['image']['containerimage.digest'])
          ")
          mkdir -p "${RUNNER_TEMP}/digests"
          touch "${RUNNER_TEMP}/digests/${digest#sha256:}"
      - name: Upload ${{ matrix.arch }} digest
        uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
        with:
          name: digests-${{ matrix.arch }}
          path: ${{ runner.temp }}/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    name: merge
    needs: [build]
    if: github.event_name == 'push' || github.event_name == 'schedule' || github.event_name == 'workflow_dispatch'
    runs-on: ubuntu-24.04
    permissions:
      contents: read
      packages: write
      id-token: write
      security-events: write
    outputs:
      digest: ${{ steps.merge.outputs.digest }}
    steps:
      - uses: docker/setup-buildx-action@f87e5991a6d7451dcb8d9637bfbc97413f497069 # v4.4.1
      - uses: docker/login-action@dbcb813823bdd20940b903addbd779551569679f # v4.6.0
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}
      - name: Download per-arch digests
        uses: actions/download-artifact@9000827ccba6bdab643e8b6fd33ac0654aef8333 # v8.0.2
        with:
          path: ${{ runner.temp }}/digests
          pattern: digests-*
          merge-multiple: true
      - name: Resolve publish tags
        id: tags
        run: |
          set -euo pipefail
          if [[ "${GITHUB_REF}" == refs/tags/v* ]]; then
            version="${GITHUB_REF_NAME#v}"
            if ! [[ "${version}" =~ ^[0-9]+\.[0-9]+\.[0-9]+(-[0-9A-Za-z.-]+)?$ ]]; then
              echo "::error::release tag '${GITHUB_REF_NAME}' is not semver (expected vX.Y.Z or vX.Y.Z-pre)"
              exit 1
            fi
            tags="${REGISTRY_IMAGE}:${version}"
            if [[ "${version}" != *-* ]]; then
              major="${version%%.*}"
              minor="${version#*.}"; minor="${minor%%.*}"
              tags+=",${REGISTRY_IMAGE}:${major}.${minor},${REGISTRY_IMAGE}:${major},${REGISTRY_IMAGE}:latest"
            fi
          else
            tags="${REGISTRY_IMAGE}:latest"
          fi
          echo "tags=${tags}" >> "${GITHUB_OUTPUT}"
      - name: Create multi-arch manifest (imagetools create)
        id: merge
        working-directory: ${{ runner.temp }}/digests
        run: |
          set -euo pipefail
          tag_args=()
          IFS=',' read -ra tags <<< "${{ steps.tags.outputs.tags }}"
          for tag in "${tags[@]}"; do tag_args+=(-t "${tag}"); done
          docker buildx imagetools create "${tag_args[@]}" \
            $(printf "${REGISTRY_IMAGE}@sha256:%s " *)
          digest=$(docker buildx imagetools inspect "${tags[0]}" \
            --format '{{json .Manifest.Digest}}' | tr -d '"')
          echo "digest=${digest}" >> "${GITHUB_OUTPUT}"
      - name: SBOM (syft, committed as artifact)
        uses: anchore/sbom-action@66cbf4bc1f1c0d2edc94016e65bc221b6bb0ad6c # v0.24.3
        with:
          image: ${{ env.REGISTRY_IMAGE }}@${{ steps.merge.outputs.digest }}
          artifact-name: sbom.spdx.json
      - name: Scan (trivy, gate HIGH/CRITICAL)
        uses: aquasecurity/trivy-action@ed142fd0673e97e23eac54620cfb913e5ce36c25 # v0.36.0
        with:
          image-ref: ${{ env.REGISTRY_IMAGE }}@${{ steps.merge.outputs.digest }}
          format: sarif
          output: trivy.sarif
          severity: HIGH,CRITICAL
          exit-code: "1"
          # v0.36.0 drops `--severity` for SARIF output unless this is true, so
          # without it the exit-code gate fires on every severity (not just
          # HIGH/CRITICAL); keep it true to preserve the gate.
          limit-severities-for-sarif: "true"
      - name: Upload trivy SARIF to code scanning
        # `if: always()` so the findings still reach the Security tab when the
        # gate above fails the job (exit-code 1).
        if: always()
        uses: github/codeql-action/upload-sarif@24c54180a607b1449ed407dd24f251e4e9147c8d # v4.38.3
        with:
          sarif_file: trivy.sarif
          category: trivy
      - name: Scan (grype, gate high/critical)
        id: grype
        uses: anchore/scan-action@27805bf3b4e84b4a5c980df22ed233c00390a439 # v7.4.2
        with:
          image: ${{ env.REGISTRY_IMAGE }}@${{ steps.merge.outputs.digest }}
          fail-build: true
          severity-cutoff: high
      - name: Upload grype SARIF to code scanning
        # `if: always()` so grype findings reach the Security tab even when the
        # gate above fails the job.
        if: always()
        uses: github/codeql-action/upload-sarif@24c54180a607b1449ed407dd24f251e4e9147c8d # v4.38.3
        with:
          sarif_file: ${{ steps.grype.outputs.sarif }}
          category: grype
      - uses: sigstore/cosign-installer@6f9f17788090df1f26f669e9d70d6ae9567deba6 # v4.1.2
        with:
          cosign-release: "v3.0.6"
      - name: Keyless sign (cosign, OIDC)
        env:
          COSIGN_YES: "true"
        run: |
          cosign sign "${REGISTRY_IMAGE}@${{ steps.merge.outputs.digest }}"

  pin-digest:
    name: pin-digest
    needs: [merge]
    # Only master/scheduled builds advance the committed digest; a release tag
    # must not rewrite kustomization.
    if: github.event_name != 'push' || !startsWith(github.ref, 'refs/tags/')
    runs-on: ubuntu-24.04
    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
      - uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
        with:
          python-version: "3.x"
      - name: Pin kustomization to the built digest + strict lint
        env:
          DIGEST: ${{ needs.merge.outputs.digest }}
        run: |
          pip install pyyaml
          python3 - "${DIGEST}" <<'EOF'
          import sys
          from pathlib import Path
          import yaml
          digest = sys.argv[1]
          assert digest.startswith("sha256:"), f"bad digest: {digest}"
          path = Path("deploy/k8s/kustomization.yaml")
          doc = yaml.safe_load(path.read_text())
          for img in doc.get("images", []):
              if img.get("name") == "ghcr.io/syavne/d-oauth-server":
                  img.pop("newTag", None)
                  img["digest"] = digest
          path.write_text(yaml.safe_dump(doc, sort_keys=False))
          EOF
          python3 scripts/check_manifests.py --strict-digest

  release:
    name: release
    needs: [merge]
    if: startsWith(github.ref, 'refs/tags/v')
    runs-on: ubuntu-24.04
    permissions:
      contents: write
    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
      - name: Create GitHub Release
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          DIGEST: ${{ needs.merge.outputs.digest }}
        run: |
          flags=()
          if [[ "${GITHUB_REF_NAME}" == *-* ]]; then
            flags+=(--prerelease)
          fi
          gh release create "${GITHUB_REF_NAME}" \
            --verify-tag \
            --generate-notes \
            --title "${GITHUB_REF_NAME}" \
            "${flags[@]}" \
            --notes "Container image \`${REGISTRY_IMAGE}@${DIGEST}\` (linux/amd64 + linux/arm64), signed with cosign; the SBOM and provenance attestations are attached to the image."