name: Prevent PRs against `main`

on:
  pull_request_target:
    # Please read https://securitylab.github.com/research/github-actions-preventing-pwn-requests/ before using
    types: [opened, edited]

jobs:
  check-branch:
    runs-on: ubuntu-latest
    steps:
      - uses: Vankka/pr-target-branch-action@v2
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        with:
          target: main
          exclude: next  # Don't prevent going from next -> main
          change-to: next
          comment: |
              Your PR was set to target `main`, PRs should be target `next`.

              The base branch of this PR has been automatically changed to `next`.
              Please verify that there are no merge conflicts.