name: Security Headers Validation

on:
  workflow_call:  # Called by release-gate.yml
  schedule:
    - cron: '0 3 * * *'  # Daily scan for early detection
  workflow_dispatch:  # Manual trigger for debugging/verification

permissions:
  contents: read

# NOTE: No concurrency block here. When called via workflow_call from
# release-gate.yml, the caller's workflow name is used for the concurrency
# group, which can cause this job to be cancelled if another release gate
# run starts on the same ref. The parent workflow manages concurrency.

jobs:
  validate-headers:
    runs-on: ubuntu-latest
    timeout-minutes: 15

    services:
      postgres:
        image: postgres:13@sha256:4689940c683801b4ab839ab3b0a0a3555a5fe425371422310944e89eca7d8068 # v13
        env:
          POSTGRES_USER: ldr_test
          POSTGRES_PASSWORD: ${{ github.run_id }}_test_pwd
          POSTGRES_DB: test_db
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
        ports:
          - 5432:5432

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

      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
        with:
          persist-credentials: false

      - name: Set up Python 3.12
        uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
        with:
          python-version: '3.12'

      - name: Cache pip packages
        uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
        with:
          path: ~/.cache/pip
          key: ${{ runner.os }}-pip-headers-${{ hashFiles('**/pyproject.toml') }}
          restore-keys: |
            ${{ runner.os }}-pip-headers-
            ${{ runner.os }}-pip-

      - name: Set up PDM
        uses: pdm-project/setup-pdm@973541a5febeafcfdadf8a51211435be6ecfd90f # v4.5
        with:
          python-version: '3.12'

      - name: Install system dependencies
        run: |
          sudo apt-get update
          sudo apt-get install -y libsqlcipher-dev build-essential

      - name: Install dependencies
        run: |
          pdm install --dev

      - name: Set up test environment
        run: |
          mkdir -p data
          mkdir -p research_outputs
          cp -r src/local_deep_research/defaults/.env.template .env.test

      - name: Start Flask application in background
        run: |
          # Use FLASK_DEBUG=0 (FLASK_ENV is deprecated)
          export FLASK_DEBUG=0
          export DATABASE_URL=postgresql://ldr_test:${{ github.run_id }}_test_pwd@localhost:5432/test_db
          pdm run python -m local_deep_research.web.app &
          echo $! > flask.pid

      - name: Wait for application to be ready
        run: |
          timeout 60 bash -c 'until curl -fsS --connect-timeout 2 --max-time 5 http://localhost:5000/api/v1/health > /dev/null; do sleep 2; done'

      - name: Validate security headers
        run: |
          echo "=== Testing Security Headers ==="
          echo ""

          # Capture headers once for efficiency (with timeout)
          HEADERS=$(curl -sI --max-time 10 http://localhost:5000/)

          echo "Full response headers:"
          echo "$HEADERS"
          echo ""

          # Check for required security headers and validate values
          ERRORS=()

          # X-Frame-Options - must be SAMEORIGIN or DENY
          XFO=$(echo "$HEADERS" | grep -i "^X-Frame-Options:" | cut -d':' -f2- | tr -d '\r' | xargs)
          if [[ -z "$XFO" ]]; then
            ERRORS+=("X-Frame-Options: MISSING")
          elif [[ "$XFO" != "SAMEORIGIN" && "$XFO" != "DENY" ]]; then
            ERRORS+=("X-Frame-Options: Invalid value '$XFO' (expected SAMEORIGIN or DENY)")
          else
            echo "✅ X-Frame-Options: $XFO"
          fi

          # X-Content-Type-Options - must be nosniff
          XCTO=$(echo "$HEADERS" | grep -i "^X-Content-Type-Options:" | cut -d':' -f2- | tr -d '\r' | xargs)
          if [[ -z "$XCTO" ]]; then
            ERRORS+=("X-Content-Type-Options: MISSING")
          elif [[ "$XCTO" != "nosniff" ]]; then
            ERRORS+=("X-Content-Type-Options: Invalid value '$XCTO' (expected nosniff)")
          else
            echo "✅ X-Content-Type-Options: $XCTO"
          fi

          # Referrer-Policy - must not be unsafe
          RP=$(echo "$HEADERS" | grep -i "^Referrer-Policy:" | cut -d':' -f2- | tr -d '\r' | xargs)
          if [[ -z "$RP" ]]; then
            ERRORS+=("Referrer-Policy: MISSING")
          elif [[ "$RP" == "unsafe-url" || "$RP" == "no-referrer-when-downgrade" ]]; then
            ERRORS+=("Referrer-Policy: Insecure value '$RP'")
          else
            echo "✅ Referrer-Policy: $RP"
          fi

          # Permissions-Policy - must restrict dangerous features
          PP=$(echo "$HEADERS" | grep -i "^Permissions-Policy:" | cut -d':' -f2- | tr -d '\r' | xargs)
          if [[ -z "$PP" ]]; then
            ERRORS+=("Permissions-Policy: MISSING")
          elif [[ "$PP" != *"geolocation=()"* ]]; then
            ERRORS+=("Permissions-Policy: Should restrict geolocation")
          else
            echo "✅ Permissions-Policy: $PP"
          fi

          # Content-Security-Policy - must have default-src and not be overly permissive
          CSP=$(echo "$HEADERS" | grep -i "^Content-Security-Policy:" | cut -d':' -f2- | tr -d '\r' | xargs)
          if [[ -z "$CSP" ]]; then
            ERRORS+=("Content-Security-Policy: MISSING")
          elif [[ "$CSP" == *"default-src *"* || "$CSP" == *"default-src 'unsafe-inline' 'unsafe-eval'"* ]]; then
            ERRORS+=("Content-Security-Policy: Overly permissive policy detected")
          elif [[ "$CSP" != *"default-src"* ]]; then
            ERRORS+=("Content-Security-Policy: Missing default-src directive")
          else
            echo "✅ Content-Security-Policy: Present with default-src"
          fi

          # Report results
          echo ""
          if [ ${#ERRORS[@]} -eq 0 ]; then
            echo "✅ All required security headers are present and valid"
          else
            echo "❌ Security header issues found:"
            for error in "${ERRORS[@]}"; do
              echo "  - $error"
            done
            exit 1
          fi

      - name: Test API endpoint headers
        run: |
          echo "=== Testing Security Headers on API Endpoints ==="
          echo ""

          # Test health endpoint (with timeout)
          API_HEADERS=$(curl -sI --max-time 10 http://localhost:5000/api/health)

          if echo "$API_HEADERS" | grep -iq "^X-Frame-Options:"; then
            echo "✅ Security headers present on API endpoints"
          else
            echo "❌ Security headers missing on API endpoints"
            echo "$API_HEADERS"
            exit 1
          fi

      - name: Cleanup
        if: always()
        run: |
          if [ -f flask.pid ]; then
            kill "$(cat flask.pid)" 2>/dev/null || true
            rm -f flask.pid
          fi