name: Prerelease Docker Image

# Build the canonical Docker image for a release.  In the build-once-promote
# pipeline, this workflow IS the build — docker-publish.yml only retags the
# manifest produced here.  Cosign signing, SBOM attestation, and SLSA
# provenance are attached here once, keyed by manifest digest, so they're
# discoverable from any tag (including the release tags later created by
# imagetools create).
#
# Triggered exclusively via workflow_call from release.yml (after security
# gates pass).  No workflow_dispatch — security and gate semantics are
# enforced by the caller.  The build runs automatically; the only human
# approval in the release flow is the `release` env on this workflow's
# jobs + publish-docker + trigger-pypi + create-release in release.yml
# (gates the actual publish, not the canonical build).

on:
  workflow_call:
    inputs:
      version:
        description: "Bare semver, e.g. '1.6.9' (no leading 'v')"
        type: string
        required: true
      short_sha:
        description: "First 7 chars of commit SHA (used in the prerelease tag)"
        type: string
        required: true
    secrets:
      # Explicit secrets contract instead of `secrets: inherit` on the
      # caller side — narrower blast radius if a future caller misuses
      # this reusable workflow.
      DOCKER_USERNAME:
        required: true
        description: "Docker Hub username for image push"
      DOCKER_PASSWORD:
        required: true
        description: "Docker Hub PAT (Read+Write+Delete scopes)"
    outputs:
      manifest_digest:
        description: "sha256:... digest of the multi-arch prerelease manifest. Used by docker-publish.yml to verify retag preserves the digest."
        value: ${{ jobs.create-manifest.outputs.digest }}

permissions: {}  # Minimal top-level for OSSF Scorecard Token-Permissions

# No approval gate at the build step — the build runs automatically once
# security gates and CI gates in release.yml pass. The only meaningful
# human decision in the release flow is "should this signed, attested,
# tested image become the official release?" — gated by the `release`
# environment on this workflow's jobs + `publish-docker` + `trigger-pypi`
# + `create-release` in release.yml. The maintainer can pull
# `:prerelease-v<ver>-<sha>` and smoke-test between build completion
# and approving the release env.

jobs:
  build-amd64:
    name: Build AMD64 Prerelease Image
    runs-on: ubuntu-latest
    environment: release
    permissions:
      contents: read

    steps:
      - name: Harden Runner
        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
        with:
          egress-policy: audit

      - name: Check out the repo
        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
        with:
          persist-credentials: false
          fetch-depth: 0

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@bb05f3f5519dd87d3ba754cc423b652a5edd6d2c # v4.2.0

      - name: Log in to Docker Hub
        uses: docker/login-action@af1e73f918a031802d376d3c8bbc3fe56130a9b0 # v4.4.0
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}

      - name: Build and push AMD64 image
        id: build
        uses: docker/build-push-action@f9f3042f7e2789586610d6e8b85c8f03e5195baf # v7.2.0
        with:
          context: .
          platforms: linux/amd64
          push: true
          tags: ${{ secrets.DOCKER_USERNAME }}/local-deep-research:prerelease-v${{ inputs.version }}-${{ inputs.short_sha }}-amd64
          cache-from: type=gha,scope=linux-amd64
          cache-to: type=gha,mode=max,scope=linux-amd64

  build-arm64:
    name: Build ARM64 Prerelease Image
    runs-on: ubuntu-24.04-arm
    environment: release
    permissions:
      contents: read

    steps:
      - name: Harden Runner
        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
        with:
          egress-policy: audit

      - name: Check out the repo
        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
        with:
          persist-credentials: false
          fetch-depth: 0

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@bb05f3f5519dd87d3ba754cc423b652a5edd6d2c # v4.2.0

      - name: Log in to Docker Hub
        uses: docker/login-action@af1e73f918a031802d376d3c8bbc3fe56130a9b0 # v4.4.0
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}

      - name: Build and push ARM64 image
        id: build
        uses: docker/build-push-action@f9f3042f7e2789586610d6e8b85c8f03e5195baf # v7.2.0
        with:
          context: .
          platforms: linux/arm64
          push: true
          tags: ${{ secrets.DOCKER_USERNAME }}/local-deep-research:prerelease-v${{ inputs.version }}-${{ inputs.short_sha }}-arm64
          cache-from: type=gha,scope=linux-arm64
          cache-to: type=gha,mode=max,scope=linux-arm64

  security-scan:
    name: Security Scan
    runs-on: ubuntu-latest
    environment: release
    permissions:
      contents: read

    steps:
      - name: Harden the runner (Audit all outbound calls)
        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
        with:
          egress-policy: audit

      - name: Check out the repo
        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
        with:
          persist-credentials: false
          fetch-depth: 0

      - name: Free disk space
        run: |
          sudo rm -rf /usr/share/dotnet || true
          sudo rm -rf /usr/local/lib/android || true
          sudo rm -rf /opt/ghc || true
          sudo rm -rf /opt/hostedtoolcache/CodeQL || true
          sudo docker image prune --all --force || true
          df -h

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@bb05f3f5519dd87d3ba754cc423b652a5edd6d2c # v4.2.0

      - name: Build Docker image for security scan
        uses: docker/build-push-action@f9f3042f7e2789586610d6e8b85c8f03e5195baf # v7.2.0
        with:
          context: .
          platforms: linux/amd64
          push: false
          load: true
          tags: local-deep-research:security-scan
          cache-from: type=gha,scope=linux-amd64
          cache-to: type=gha,mode=max,scope=linux-amd64

      # Generate Trivy SARIF for archival as a workflow artifact (all severities, never fails).
      # Severity-gating happens in the next step.
      - name: Generate Trivy SARIF report
        uses: aquasecurity/trivy-action@ed142fd0673e97e23eac54620cfb913e5ce36c25 # v0.36.0
        with:
          image-ref: local-deep-research:security-scan
          format: 'sarif'
          output: 'trivy-prerelease-scan.sarif'
          ignore-unfixed: true
          exit-code: '0'
          version: 'v0.69.2'

      # Separate scan that fails build only on fixable HIGH/CRITICAL vulnerabilities
      - name: Check for fixable HIGH/CRITICAL vulnerabilities
        uses: aquasecurity/trivy-action@ed142fd0673e97e23eac54620cfb913e5ce36c25 # v0.36.0
        with:
          image-ref: local-deep-research:security-scan
          severity: 'CRITICAL,HIGH'
          ignore-unfixed: true
          trivyignores: '.trivyignore'
          exit-code: '1'
          version: 'v0.69.2'

      - name: Upload Trivy scan results
        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
        if: always()
        with:
          name: trivy-prerelease-scan
          path: trivy-prerelease-scan.sarif
          retention-days: 7

  create-manifest:
    name: Create Multi-Platform Prerelease Manifest
    needs: [build-amd64, build-arm64, security-scan]
    runs-on: ubuntu-latest
    environment: release
    permissions:
      contents: read
      id-token: write    # Required for cosign keyless OIDC signing
      # No `packages: write` — Docker Hub auth uses DOCKER_PASSWORD secret,
      # not GITHUB_TOKEN. `packages: write` only matters for ghcr.io pushes.
    outputs:
      digest: ${{ steps.capture-digest.outputs.digest }}

    steps:
      - name: Harden Runner
        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411 # v2.19.4
        with:
          egress-policy: audit

      - name: Check out the repo
        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
        with:
          persist-credentials: false
          fetch-depth: 0

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@bb05f3f5519dd87d3ba754cc423b652a5edd6d2c # v4.2.0

      - name: Log in to Docker Hub
        uses: docker/login-action@af1e73f918a031802d376d3c8bbc3fe56130a9b0 # v4.4.0
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}

      - name: Install Cosign
        uses: sigstore/cosign-installer@6f9f17788090df1f26f669e9d70d6ae9567deba6 # v4.1.2
        with:
          # Pin to cosign v2.x — see release.yml for rationale (v3 enables
          # --new-bundle-format by default which changes the on-wire format
          # and breaks downstream verifiers still on v2).
          cosign-release: 'v2.6.3'

      - name: Install Syft
        uses: anchore/sbom-action/download-syft@e22c389904149dbc22b58101806040fa8d37a610 # v0.24.0

      - name: Create and push multi-platform manifest
        env:
          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
          VERSION: ${{ inputs.version }}
          SHORT_SHA: ${{ inputs.short_sha }}
        run: |
          set -euo pipefail
          TAG="prerelease-v${VERSION}-${SHORT_SHA}"
          echo "Creating manifest for: ${DOCKER_USERNAME}/local-deep-research:${TAG}"
          docker buildx imagetools create -t "${DOCKER_USERNAME}/local-deep-research:${TAG}" \
            "${DOCKER_USERNAME}/local-deep-research:${TAG}-amd64" \
            "${DOCKER_USERNAME}/local-deep-research:${TAG}-arm64"
          echo "Manifest created successfully"

          # Floating tag: re-point :prerelease at the manifest just created so
          # testers can pin compose to `:prerelease` and pull the latest RC via
          # `docker compose pull` without editing the tag each cycle. The
          # versioned tag above remains for reproducibility (and is what
          # docker-publish.yml retags by digest into :1.6.9 / :1.6 / :latest).
          echo "Updating floating tag: ${DOCKER_USERNAME}/local-deep-research:prerelease"
          docker buildx imagetools create -t "${DOCKER_USERNAME}/local-deep-research:prerelease" \
            "${DOCKER_USERNAME}/local-deep-research:${TAG}"
          echo "Floating :prerelease tag updated"

      - name: Capture manifest digest
        id: capture-digest
        env:
          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
          VERSION: ${{ inputs.version }}
          SHORT_SHA: ${{ inputs.short_sha }}
        run: |
          set -euo pipefail
          IMAGE_REF="${DOCKER_USERNAME}/local-deep-research:prerelease-v${VERSION}-${SHORT_SHA}"
          # Same form as the existing docker-publish.yml inspector — avoids jq.
          DIGEST=$(docker buildx imagetools inspect "$IMAGE_REF" --format '{{json .Manifest.Digest}}' | tr -d '"')
          if [[ -z "$DIGEST" || "$DIGEST" != sha256:* ]]; then
            echo "::error::Failed to capture manifest digest (got '${DIGEST}')"
            exit 1
          fi
          echo "digest=${DIGEST}" >> "$GITHUB_OUTPUT"
          echo "Manifest digest: ${DIGEST}"

      - name: Sign manifest with Cosign
        env:
          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
          DIGEST: ${{ steps.capture-digest.outputs.digest }}
        run: |
          set -euo pipefail
          # Sign by digest — signature artifact lands at sha256-<digest>.sig
          # in the same repo, discoverable from ANY tag pointing at the same
          # digest (including release tags created later by docker-publish.yml's
          # imagetools-create retag).
          IMAGE_REF="${DOCKER_USERNAME}/local-deep-research@${DIGEST}"
          echo "Signing image by digest: $IMAGE_REF"
          cosign sign --yes "$IMAGE_REF"
          # Brief sleep to allow registry to propagate signature
          sleep 5

      - name: Generate SLSA provenance attestation
        env:
          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
          DIGEST: ${{ steps.capture-digest.outputs.digest }}
        run: |
          set -euo pipefail
          IMAGE_REF="${DOCKER_USERNAME}/local-deep-research@${DIGEST}"

          # entryPoint is the TOP-LEVEL caller (release.yml), not this
          # reusable workflow. Per SLSA GHA buildtype v1 and the canonical
          # slsa-github-generator, reusable workflows are explicitly NOT
          # entryPoints. github.run_id / github.repository / github.sha all
          # resolve to the caller's run context inside a reusable workflow.
          # builder.id pins the workflow that actually defines the build
          # steps — the trust root a verifier policy can pin against. We
          # compose it from `github.repository` and a hardcoded path to
          # THIS workflow file, with `github.ref` for the ref portion.
          # Rationale: inside a workflow_call callee, the `github` context
          # is scoped to the CALLER, so `github.workflow_ref` would point
          # at release.yml (the wrong builder). The `job` context has no
          # `workflow_ref` property either (only check_run_id, container,
          # services, status — actionlint confirms). For a local-path
          # reusable workflow (`uses: ./.github/workflows/...`), the
          # callee's ref equals the caller's `github.ref`, so composing
          # the path manually gives the correct
          # `<owner>/<repo>/.github/workflows/prerelease-docker.yml@<ref>`
          # format that matches the Fulcio cert SAN. Cosign and
          # slsa-verifier both anchor on the cert anyway, so this fix is
          # about correctness for raw-JSON policy engines / audit tools
          # that read builder.id directly.
          #
          # completeness.* are FALSE because we don't capture invocation
          # parameters or environment, and the build does network I/O for
          # apt/pip/npm. Honest emptiness > false claims of completeness.
          #
          # buildInvocationId includes run_attempt so re-runs are
          # distinguishable in audit logs.
          #
          # Uses auto-injected GITHUB_* shell env vars (GITHUB_REPOSITORY,
          # GITHUB_REF, GITHUB_SHA, GITHUB_RUN_ID, GITHUB_RUN_ATTEMPT) instead
          # of github-context template expansion to satisfy zizmor's
          # template-injection check. The values are semantically identical
          # inside a workflow_call callee (both scope to the caller's context),
          # but shell-var expansion happens at runtime in a confined string
          # context, eliminating any theoretical injection surface from a
          # ref/branch name containing shell metacharacters.
          cat > provenance.json <<EOF
          {
            "buildType": "https://github.com/${GITHUB_REPOSITORY}/docker-build@v1",
            "builder": {
              "id": "https://github.com/${GITHUB_REPOSITORY}/.github/workflows/prerelease-docker.yml@${GITHUB_REF}"
            },
            "invocation": {
              "configSource": {
                "uri": "https://github.com/${GITHUB_REPOSITORY}",
                "digest": {
                  "sha1": "${GITHUB_SHA}"
                },
                "entryPoint": ".github/workflows/release.yml"
              }
            },
            "metadata": {
              "buildInvocationId": "${GITHUB_RUN_ID}-${GITHUB_RUN_ATTEMPT}",
              "buildStartedOn": "$(date -u +%Y-%m-%dT%H:%M:%SZ)",
              "completeness": {
                "parameters": false,
                "environment": false,
                "materials": false
              },
              "reproducible": false
            },
            "materials": [
              {
                "uri": "https://github.com/${GITHUB_REPOSITORY}",
                "digest": {
                  "sha1": "${GITHUB_SHA}"
                }
              }
            ]
          }
          EOF

          # --replace prevents duplicate SLSA attestations on re-run. Cosign's
          # Replace logic is keyed by predicate-type URI, so it leaves the
          # SBOM SPDX attestation (different predicateType) untouched.
          cosign attest --yes --replace --predicate provenance.json --type slsaprovenance "$IMAGE_REF"

      - name: Verify image signature
        env:
          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
          DIGEST: ${{ steps.capture-digest.outputs.digest }}
        run: |
          set -euo pipefail
          IMAGE_REF="${DOCKER_USERNAME}/local-deep-research@${DIGEST}"
          echo "Verifying signature for: $IMAGE_REF"
          # Retry to handle registry propagation delay after signing
          MAX_RETRIES=5
          RETRY_DELAY=10
          for i in $(seq 1 "$MAX_RETRIES"); do
            echo "Verification attempt $i of $MAX_RETRIES..."
            # Use GITHUB_REPOSITORY shell env var (auto-injected) instead of
            # github.repository template expansion to avoid zizmor's
            # template-injection finding.
            if cosign verify \
              --certificate-identity-regexp="https://github.com/${GITHUB_REPOSITORY}" \
              --certificate-oidc-issuer=https://token.actions.githubusercontent.com \
              "$IMAGE_REF"; then
              echo "Signature verification successful!"
              exit 0
            fi
            if [ "$i" -lt "$MAX_RETRIES" ]; then
              echo "Verification failed, waiting ${RETRY_DELAY}s before retry..."
              sleep "$RETRY_DELAY"
            fi
          done
          echo "::error::Signature verification failed after $MAX_RETRIES attempts"
          exit 1

      - name: Generate per-platform SBOMs and attest each
        env:
          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
          DIGEST: ${{ steps.capture-digest.outputs.digest }}
        run: |
          set -euo pipefail
          REPO="${DOCKER_USERNAME}/local-deep-research"
          MANIFEST_REF="${REPO}@${DIGEST}"

          # Multi-arch SBOM correctness: syft against a manifest list digest
          # only scans the host platform's layers (per anchore/syft#1708),
          # which would lie to ARM64 consumers. We attest each per-arch
          # digest with its OWN SBOM so end-user verification is honest.
          # We deliberately do NOT also produce a "manifest-level SBOM" —
          # that would be amd64-only (host arch) and re-introduce the lie
          # for any arm64 consumer running the README verifier recipe.
          # The README documents the per-arch verification flow instead.
          MANIFEST_JSON=$(docker buildx imagetools inspect "${MANIFEST_REF}" --raw)

          # Defense against future buildx output changes: assert at least
          # one per-arch entry exists. Without this, an empty/malformed
          # manifest list would silently produce zero SBOMs and pass CI green.
          PER_ARCH_COUNT=$(echo "${MANIFEST_JSON}" \
            | jq '[.manifests[] | select(.platform.architecture != "unknown")] | length')
          if [[ "${PER_ARCH_COUNT}" -lt 1 ]]; then
            echo "::error::No per-arch manifest entries found in ${MANIFEST_REF} — SBOM generation cannot proceed"
            echo "Raw manifest: ${MANIFEST_JSON}"
            exit 1
          fi
          echo "Found ${PER_ARCH_COUNT} per-arch manifest(s) to scan"

          echo "$MANIFEST_JSON" \
            | jq -r '.manifests[] | select(.platform.architecture != "unknown") | "\(.platform.os)/\(.platform.architecture)\t\(.digest)"' \
            | while IFS=$'\t' read -r PLAT PER_ARCH_DIGEST; do
                ARCH="${PLAT##*/}"
                PER_ARCH_REF="${REPO}@${PER_ARCH_DIGEST}"
                SBOM_FILE="sbom-${ARCH}.spdx.json"
                echo "=== Scanning ${PLAT} (${PER_ARCH_DIGEST}) ==="
                # --platform tells syft which arch to scan — matters when
                # the host runner can't natively execute the image.
                syft --platform "${PLAT}" "${PER_ARCH_REF}" -o spdx-json > "${SBOM_FILE}"
                # --replace prevents accumulation when a re-run lands on
                # the same digest (e.g. "Re-run failed jobs" after a flake).
                # Per cosign source pkg/cosign/remote/remote.go, --replace
                # is per-predicate-type, so it doesn't disturb the SLSA
                # attestation already on the manifest list digest.
                cosign attest --yes --replace \
                  --predicate "${SBOM_FILE}" --type spdxjson "${PER_ARCH_REF}"
              done

      - name: Upload SBOMs artifact
        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
        with:
          name: sbom
          # Per-arch SBOMs only — `sbom-amd64.spdx.json`, `sbom-arm64.spdx.json`,
          # one per platform in the manifest list. No manifest-level SBOM is
          # produced (would be host-arch-only and misleading for non-amd64
          # consumers).
          path: sbom-*.spdx.json
          retention-days: 90

      - name: Summary
        env:
          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
          VERSION: ${{ inputs.version }}
          SHORT_SHA: ${{ inputs.short_sha }}
          DIGEST: ${{ steps.capture-digest.outputs.digest }}
        run: |
          TAG="prerelease-v${VERSION}-${SHORT_SHA}"
          {
            echo "## Prerelease Docker Image"
            echo ""
            echo "**Versioned tag:** \`${TAG}\`"
            echo "**Floating tag:** \`prerelease\` (now points at this build)"
            echo ""
            echo "**Digest:** \`${DIGEST}\`"
            echo ""
            echo '```'
            echo "docker pull ${DOCKER_USERNAME}/local-deep-research:${TAG}"
            echo "docker pull ${DOCKER_USERNAME}/local-deep-research:prerelease"
            echo '```'
            echo ""
            echo "Signed and attested. After release approval, docker-publish.yml"
            echo "will retag this exact digest as \`:${VERSION}\`, \`:major.minor\`,"
            echo "and \`:latest\`."
          } >> "$GITHUB_STEP_SUMMARY"