name: Run Trivy Scan

on:
  workflow_call:
    inputs:
      scan-config:
        description: "Run Trivy config scan (repository root)."
        required: false
        type: boolean
        default: false
      scan-images:
        description: "Run Trivy image scan on images from image-scan-files."
        required: false
        type: boolean
        default: false
      image-scan-files:
        description: "YAML list of files to extract container images from. Used when scan-images is true."
        required: false
        type: string
        default: ""
      trivy-server-url:
        description: "Optional Trivy server URL for image scan."
        required: false
        type: string
        default: ""
    outputs:
      merged-sarif-artifact:
        description: "Artifact name containing the merged SARIF file (download this artifact; file inside is merged-sarif.json)."
        value: ${{ jobs.merge.outputs.merged-sarif-artifact }}
      merged-sarif-path:
        description: "Path to the merged SARIF file inside the artifact (merged-sarif.json)."
        value: ${{ jobs.merge.outputs.merged-sarif-path }}

jobs:
  config-scan:
    if: inputs.scan-config
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
      - uses: https://gitea.t000-n.de/t.behrendt/trivy-actions/setup-trivy@1.4.4
      - uses: https://gitea.t000-n.de/t.behrendt/trivy-actions/setup-db@1.4.4
      - run: |
          trivy config --cache-dir "$TRIVY_CACHE_DIR" --exit-code 0 --format sarif --output config-sarif.json .
        env:
          TRIVY_CACHE_DIR: ${{ runner.temp }}/trivy
      - uses: https://github.com/ChristopherHX/gitea-upload-artifact@v4
        with:
          name: config-sarif
          path: config-sarif.json

  image-scan:
    if: inputs.scan-images
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
      - uses: https://gitea.t000-n.de/t.behrendt/trivy-actions/setup-trivy@1.4.4
      - uses: https://gitea.t000-n.de/t.behrendt/trivy-actions/setup-db@1.4.4 
      - name: Get images from files
        id: get-images
        uses: https://gitea.t000-n.de/t.behrendt/trivy-actions/get-images-from-files@1.4.4
        with:
          files: ${{ inputs.image-scan-files }}
      - name: Pull images
        if: steps.get-images.outputs.images != '[]'
        run: |
          set -e
          images='${{ steps.get-images.outputs.images }}'
          for img in $(echo "$images" | jq -r '.[]'); do
            docker pull "$img"
          done
      - name: Scan images
        id: scan
        if: steps.get-images.outputs.images != '[]'
        run: |
          set -e
          images='${{ steps.get-images.outputs.images }}'
          count=$(echo "$images" | jq 'length')
          if [ "$count" -eq 0 ]; then
            echo "count=0" >> "$GITHUB_OUTPUT"
            exit 0
          fi
          i=0
          server="${{ inputs.trivy-server-url }}"
          for img in $(echo "$images" | jq -r '.[]'); do
            args=(image --cache-dir "$TRIVY_CACHE_DIR" --exit-code 0 --scanners vuln --format sarif --output "sarif-image-${i}.json" "$img")
            [ -n "$server" ] && args+=(--server "$server")
            trivy "${args[@]}"
            i=$((i + 1))
          done
          {
            echo "files<<EOF"
            for j in $(seq 0 $((i - 1))); do echo "  - sarif-image-${j}.json"; done
            echo "EOF"
          } >> $GITHUB_OUTPUT
          echo "count=$i" >> $GITHUB_OUTPUT
        env:
          TRIVY_CACHE_DIR: ${{ runner.temp }}/trivy
      - name: Merge image SARIF files
        if: steps.get-images.outputs.images != '[]' && steps.scan.outputs.count != '0'
        uses: https://gitea.t000-n.de/t.behrendt/trivy-actions/merge-sarif-files@1.4.4
        with:
          files: ${{ steps.scan.outputs.files }}
          output-file: image-sarif.json
      - name: Ensure image SARIF exists (no images case)
        if: steps.get-images.outputs.images == '[]' || steps.scan.outputs.count == '0'
        run: |
          echo '{"version":"2.1.0","$schema":"https://raw.githubusercontent.com/oasis-tcs/sarif-spec/master/Schemata/sarif-schema-2.1.0.json","runs":[]}' > image-sarif.json
      - uses: https://github.com/ChristopherHX/gitea-upload-artifact@v4
        with:
          name: image-sarif
          path: image-sarif.json

  merge:
    runs-on: ubuntu-latest
    needs: [config-scan, image-scan]
    if: always() && (needs.config-scan.result == 'success' || needs.config-scan.result == 'skipped') && (needs.image-scan.result == 'success' || needs.image-scan.result == 'skipped') && (inputs.scan-config || inputs.scan-images)
    outputs:
      merged-sarif-artifact: ${{ steps.outputs.outputs.merged-sarif-artifact }}
      merged-sarif-path: ${{ steps.outputs.outputs.merged-sarif-path }}
    steps:
      - name: Require at least one scan
        if: ${{ !inputs.scan-config && !inputs.scan-images }}
        run: |
          echo "Enable scan-config and/or scan-images (and provide image-scan-files for image scan)."
          exit 1
      - name: Download config SARIF
        if: inputs.scan-config
        uses: https://github.com/ChristopherHX/gitea-download-artifact@v4
        with:
          name: config-sarif
          path: config-sarif-artifact
      - name: Download image SARIF
        if: inputs.scan-images
        uses: https://github.com/ChristopherHX/gitea-download-artifact@v4
        with:
          name: image-sarif
          path: image-sarif-artifact
      - name: Build merge file list
        id: file-list
        run: |
          files=""
          if [ "${{ inputs.scan-config }}" = "true" ] && [ -f config-sarif-artifact/config-sarif.json ]; then
            files="- config-sarif-artifact/config-sarif.json"
          fi
          if [ "${{ inputs.scan-images }}" = "true" ] && [ -f image-sarif-artifact/image-sarif.json ]; then
            [ -n "$files" ] && files="$files"$'\n'"  - image-sarif-artifact/image-sarif.json" || files="- image-sarif-artifact/image-sarif.json"
          fi
          echo "files<<EOF" >> "$GITHUB_OUTPUT"
          echo "$files" >> "$GITHUB_OUTPUT"
          echo "EOF" >> "$GITHUB_OUTPUT"
      - name: Merge SARIF files
        id: merge-step
        uses: https://gitea.t000-n.de/t.behrendt/trivy-actions/merge-sarif-files@1.4.4
        with:
          files: ${{ steps.file-list.outputs.files }}
          output-file: merged-sarif.json
      - name: Set outputs
        id: outputs
        run: |
          echo "merged-sarif-artifact=merged-sarif" >> "$GITHUB_OUTPUT"
          echo "merged-sarif-path=merged-sarif.json" >> "$GITHUB_OUTPUT"
      - uses: https://github.com/ChristopherHX/gitea-upload-artifact@v4
        with:
          name: merged-sarif
          path: merged-sarif.json