name: PR Lint and Validation Gate

on:
  pull_request:
    branches: [ "main" ]
  workflow_dispatch: {}

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

jobs:
  yaml-and-whitespace:
    name: YAML and Whitespace
    runs-on: ubuntu-latest
    outputs:
      elapsed_seconds: ${{ steps.elapsed.outputs.seconds }}
    steps:
      - name: Start timer
        run: echo "START_TS=$(date +%s)" >> "$GITHUB_ENV"

      - name: Checkout
        uses: actions/checkout@v4

      - name: Install yamllint
        run: |
          python3 -m pip install --upgrade pip
          python3 -m pip install yamllint

      - name: Run yamllint
        run: |
          yamllint -d "{extends: default, rules: {line-length: {max: 180}, truthy: disable}}" .

      - name: Check trailing whitespace
        run: |
          if git ls-files -z | xargs -0 -I{} grep -nH -E "[[:blank:]]+$" "{}" \
            --exclude="*.md" --exclude="*.svg"; then
            echo "Trailing whitespace found"
            exit 1
          fi

      - name: Capture duration
        id: elapsed
        if: always()
        run: |
          end_ts=$(date +%s)
          start_ts=${START_TS:-$end_ts}
          echo "seconds=$((end_ts - start_ts))" >> "$GITHUB_OUTPUT"

  helm-lint:
    name: Helm Lint
    runs-on: ubuntu-latest
    outputs:
      elapsed_seconds: ${{ steps.elapsed.outputs.seconds }}
    steps:
      - name: Start timer
        run: echo "START_TS=$(date +%s)" >> "$GITHUB_ENV"

      - name: Checkout
        uses: actions/checkout@v4

      - name: Install Helm
        uses: azure/setup-helm@v4

      - name: Lint all charts
        run: |
          mapfile -t charts < <(find . -type f -name Chart.yaml -print)
          if [ -z "${charts[0]:-}" ]; then
            echo "No Helm charts found; skipping"
            exit 0
          fi

          failed=0
          for chart in "${charts[@]}"; do
            chart_dir="$(dirname "$chart")"
            echo "Linting ${chart_dir}"
            if ! helm lint "$chart_dir"; then
              failed=1
            fi
          done
          exit $failed

      - name: Capture duration
        id: elapsed
        if: always()
        run: |
          end_ts=$(date +%s)
          start_ts=${START_TS:-$end_ts}
          echo "seconds=$((end_ts - start_ts))" >> "$GITHUB_OUTPUT"

  terraform-lint:
    name: Terraform Validate and TFLint
    runs-on: ubuntu-latest
    outputs:
      elapsed_seconds: ${{ steps.elapsed.outputs.seconds }}
    steps:
      - name: Start timer
        run: echo "START_TS=$(date +%s)" >> "$GITHUB_ENV"

      - name: Checkout
        uses: actions/checkout@v4

      - name: Setup Terraform
        uses: hashicorp/setup-terraform@v3

      - name: Install TFLint
        run: |
          curl -s https://raw.githubusercontent.com/terraform-linters/tflint/master/install_linux.sh | bash

      - name: Validate Terraform directories
        run: |
          mapfile -t tf_dirs < <(find . -type f -name "*.tf" -exec dirname {} \; | sort -u)
          if [ -z "${tf_dirs[0]:-}" ]; then
            echo "No Terraform files found; skipping"
            exit 0
          fi

          failed=0
          for dir in "${tf_dirs[@]}"; do
            echo "Validating ${dir}"
            (
              cd "$dir"
              terraform init -backend=false -input=false -no-color
              terraform validate -no-color
              tflint --chdir .
            ) || failed=1
          done
          exit $failed

      - name: Capture duration
        id: elapsed
        if: always()
        run: |
          end_ts=$(date +%s)
          start_ts=${START_TS:-$end_ts}
          echo "seconds=$((end_ts - start_ts))" >> "$GITHUB_OUTPUT"

  policy-and-deps:
    name: Policy and Dependency Scan
    runs-on: ubuntu-latest
    outputs:
      elapsed_seconds: ${{ steps.elapsed.outputs.seconds }}
    steps:
      - name: Start timer
        run: echo "START_TS=$(date +%s)" >> "$GITHUB_ENV"

      - name: Checkout
        uses: actions/checkout@v4

      - name: Install Checkov
        run: |
          python3 -m pip install --upgrade pip
          python3 -m pip install checkov

      - name: Run Checkov (Kubernetes)
        run: |
          checkov -d . --framework kubernetes --skip-path "examples/default/rendered/.*" --quiet

      - name: npm audit (if package.json exists)
        run: |
          if [ -f package.json ]; then
            npm install --no-audit --no-fund
            npm audit --audit-level=high
          else
            echo "No package.json found; skipping npm audit"
          fi

      - name: Maven dependency-check (if pom.xml exists)
        run: |
          if [ -f pom.xml ]; then
            mvn -B org.owasp:dependency-check-maven:check
          else
            echo "No pom.xml found; skipping Maven dependency-check"
          fi

      - name: Capture duration
        id: elapsed
        if: always()
        run: |
          end_ts=$(date +%s)
          start_ts=${START_TS:-$end_ts}
          echo "seconds=$((end_ts - start_ts))" >> "$GITHUB_OUTPUT"

  runtime-slo:
    name: Runtime SLO (< 3 min)
    if: always()
    needs:
      - yaml-and-whitespace
      - helm-lint
      - terraform-lint
      - policy-and-deps
    runs-on: ubuntu-latest
    steps:
      - name: Enforce suite runtime budget
        run: |
          y=${{ needs.yaml-and-whitespace.outputs.elapsed_seconds || 0 }}
          h=${{ needs.helm-lint.outputs.elapsed_seconds || 0 }}
          t=${{ needs.terraform-lint.outputs.elapsed_seconds || 0 }}
          p=${{ needs.policy-and-deps.outputs.elapsed_seconds || 0 }}

          # Jobs run in parallel; full-suite wall-clock is approximated by max(job runtimes).
          suite=$y
          [ $h -gt $suite ] && suite=$h
          [ $t -gt $suite ] && suite=$t
          [ $p -gt $suite ] && suite=$p

          echo "## PR Lint Gate Runtime" >> "$GITHUB_STEP_SUMMARY"
          echo "- YAML and Whitespace: ${y}s" >> "$GITHUB_STEP_SUMMARY"
          echo "- Helm Lint: ${h}s" >> "$GITHUB_STEP_SUMMARY"
          echo "- Terraform Validate and TFLint: ${t}s" >> "$GITHUB_STEP_SUMMARY"
          echo "- Policy and Dependency Scan: ${p}s" >> "$GITHUB_STEP_SUMMARY"
          echo "- Full suite (parallel max): ${suite}s" >> "$GITHUB_STEP_SUMMARY"

          if [ $suite -gt 180 ]; then
            echo "Runtime SLO exceeded: ${suite}s > 180s"
            exit 1
          fi