name: Validate Skills

on:
  pull_request:

jobs:
  validate-skills:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'

      - run: npm ci

      # Run against only changed skills when skills files are touched; fall back
      # to full corpus validation when only tooling files changed, so validator
      # regressions against existing skills are caught in the same PR.
      - name: Validate skills
        run: |
          if git diff --name-only origin/${{ github.base_ref }}...HEAD | grep -q '^skills/'; then
            npm run validate:skills -- --changed --base=origin/${{ github.base_ref }}
          else
            npm run validate:skills
          fi