name: DevFlow PR Review

on:
  pull_request_target:
    types:
      - opened
      - reopened
      - ready_for_review
  workflow_dispatch:
    inputs:
      pr_number:
        description: Pull request number to review
        required: true
        type: string

permissions:
  contents: read
  issues: write
  pull-requests: write

concurrency:
  group: devflow-pr-review-${{ github.repository }}-${{ github.event.pull_request.number || github.run_id }}
  cancel-in-progress: true

env:
  DEVFLOW_REPOSITORY: ${{ vars.DF_REPO }}
  DEVFLOW_REF: main
  TARGET_REPO_PATH: ${{ github.workspace }}/target-repo
  DEVFLOW_PATH: ${{ github.workspace }}/devflow

jobs:
  review:
    runs-on: ubuntu-latest
    timeout-minutes: 60
    if: ${{ github.event_name != 'pull_request_target' || !github.event.pull_request.draft }}

    steps:
      - name: Resolve PR metadata
        id: pr
        shell: bash
        env:
          PR_HTML_URL: ${{ github.event.pull_request.html_url }}
          PR_NUMBER_EVENT: ${{ github.event.pull_request.number }}
          PR_NUMBER_INPUT: ${{ inputs.pr_number }}
        run: |
          set -euo pipefail

          if [[ "${GITHUB_EVENT_NAME}" == "pull_request_target" ]]; then
            pr_number="${PR_NUMBER_EVENT}"
            pr_url="${PR_HTML_URL}"
          else
            pr_number="${PR_NUMBER_INPUT}"
            pr_url="https://github.com/${GITHUB_REPOSITORY}/pull/${pr_number}"
          fi

          if [[ ! "$pr_number" =~ ^[1-9][0-9]*$ ]]; then
            echo "Could not determine PR number; for workflow_dispatch runs, the 'pr_number' input is required when not running on pull_request_target." >&2
            exit 1
          fi

          echo "pr_url=${pr_url}" >> "$GITHUB_OUTPUT"
          echo "pr_number=${pr_number}" >> "$GITHUB_OUTPUT"
          echo "repo=${GITHUB_REPOSITORY}" >> "$GITHUB_OUTPUT"

      # Safe checkout: base repo only, not the untrusted PR head.
      - name: Checkout target repo base
        uses: actions/checkout@v5
        with:
          ref: ${{ github.event_name == 'pull_request_target' && github.event.pull_request.base.sha || github.sha }}
          fetch-depth: 0
          persist-credentials: false
          path: target-repo

      # Private DevFlow checkout: the PAT/token grants access to this repo's code.
      - name: Checkout DevFlow
        uses: actions/checkout@v5
        with:
          repository: ${{ env.DEVFLOW_REPOSITORY }}
          ref: ${{ env.DEVFLOW_REF }}
          token: ${{ secrets.DEVFLOW_TOKEN }}
          fetch-depth: 1
          persist-credentials: false
          path: devflow

      - name: Set up Python
        uses: actions/setup-python@v5
        with:
          python-version: "3.13"

      - name: Set up uv
        uses: astral-sh/setup-uv@v6
        with:
          version: "0.5.x"
          enable-cache: true

      - name: Install DevFlow dependencies
        working-directory: ${{ env.DEVFLOW_PATH }}
        run: uv sync --frozen

      - name: Classify PR relevance
        id: spam
        working-directory: ${{ env.DEVFLOW_PATH }}
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          GH_COPILOT_TOKEN: ${{ secrets.GH_COPILOT_TOKEN }}
          SK_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
          AGENT_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
          PR_REPO: ${{ steps.pr.outputs.repo }}
          PR_NUMBER: ${{ steps.pr.outputs.pr_number }}
        run: |
          uv run python scripts/classify_pr_spam.py \
            --repo "$PR_REPO" \
            --pr-number "$PR_NUMBER" \
            --repo-path "${TARGET_REPO_PATH}" \
            --apply-labels

      - name: Stop after spam gate
        if: ${{ steps.spam.outputs.decision != 'allow' }}
        shell: bash
        env:
          SPAM_DECISION: ${{ steps.spam.outputs.decision }}
        run: |
          echo "Skipping review because spam gate decided: ${SPAM_DECISION}"

      - name: Run PR review
        if: ${{ steps.spam.outputs.decision == 'allow' }}
        id: review
        working-directory: ${{ env.DEVFLOW_PATH }}
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          GH_COPILOT_TOKEN: ${{ secrets.GH_COPILOT_TOKEN }}
          SK_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
          AGENT_REPO_PATH: ${{ env.TARGET_REPO_PATH }}
          PR_URL: ${{ steps.pr.outputs.pr_url }}
        run: |
          uv run python scripts/trigger_pr_review.py \
            --pr-url "$PR_URL" \
            --github-username "$GITHUB_ACTOR" \
            --no-require-comment-selection