name: Codex PR Review

on:
  pull_request_target:
    types: [opened, reopened, ready_for_review, synchronize]

concurrency:
  group: codex-pr-review-${{ github.event.pull_request.number }}
  cancel-in-progress: true

jobs:
  pr-review:
    if: |
      github.event.pull_request.draft == false &&
      !endsWith(github.actor, '[bot]') &&
      !contains(github.event.pull_request.labels.*.name, 'bot-skip')
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write
    outputs:
      review_result: ${{ steps.run_codex.outputs.final-message }}

    steps:
      - name: Check HAPI Bot review state
        id: check_bot
        uses: actions/github-script@v7
        with:
          script: |
            const marker = "*HAPI Bot*";
            const allowedLogins = (process.env.HAPI_BOT_LOGINS || "github-actions[bot]")
              .split(",")
              .map((value) => value.trim())
              .filter(Boolean);
            const currentHeadSha = context.payload.pull_request.head.sha;
            const reviews = await github.paginate(
              github.rest.pulls.listReviews,
              {
                owner: context.repo.owner,
                repo: context.repo.repo,
                pull_number: context.payload.pull_request.number,
                per_page: 100
              }
            );
            const botReviews = reviews
              .filter((review) => {
                if (!(review?.body || "").includes(marker)) {
                  return false;
                }
                const user = review.user;
                if (!user || user.type !== "Bot") {
                  return false;
                }
                return allowedLogins.includes(user.login);
              })
              .sort((left, right) => {
                const leftTime = new Date(left.submitted_at || left.created_at || 0).getTime();
                const rightTime = new Date(right.submitted_at || right.created_at || 0).getTime();
                if (rightTime !== leftTime) {
                  return rightTime - leftTime;
                }
                return (right.id || 0) - (left.id || 0);
              });
            const latestBotReview = botReviews[0];
            const hasReviewForCurrentHead = botReviews.some(
              (review) => review.commit_id === currentHeadSha
            );
            const isFollowUpReview = Boolean(
              latestBotReview?.commit_id && latestBotReview.commit_id !== currentHeadSha
            );

            core.setOutput("current_head_sha", currentHeadSha);
            core.setOutput("has_review_for_current_head", hasReviewForCurrentHead ? "true" : "false");
            core.setOutput("latest_bot_review_id", latestBotReview ? String(latestBotReview.id) : "");
            core.setOutput("latest_bot_review_commit", latestBotReview?.commit_id || "");
            core.setOutput("is_follow_up_review", isFollowUpReview ? "true" : "false");

            if (hasReviewForCurrentHead) {
              core.info(`Existing HAPI Bot review found for ${currentHeadSha}; skipping.`);
            } else if (isFollowUpReview) {
              core.info(
                `Latest HAPI Bot review was for ${latestBotReview.commit_id}; running follow-up review for ${currentHeadSha}.`
              );
            }
        env:
          HAPI_BOT_LOGINS: ${{ vars.HAPI_BOT_LOGINS }}

      - name: Checkout repository
        if: steps.check_bot.outputs.has_review_for_current_head != 'true'
        uses: actions/checkout@v4
        with:
          ref: refs/pull/${{ github.event.pull_request.number }}/merge
          fetch-depth: 0

      - name: Pre-fetch base and head refs
        if: steps.check_bot.outputs.has_review_for_current_head != 'true'
        run: |
          git fetch --no-tags origin \
            ${{ github.event.pull_request.base.ref }} \
            +refs/pull/${{ github.event.pull_request.number }}/head

      - name: Run Codex for PR Review
        id: run_codex
        if: steps.check_bot.outputs.has_review_for_current_head != 'true'
        uses: openai/codex-action@v1
        env:
          GH_TOKEN: ${{ github.token }}
          GITHUB_TOKEN: ${{ github.token }}
          CURRENT_HEAD_SHA: ${{ steps.check_bot.outputs.current_head_sha }}
          LATEST_BOT_REVIEW_ID: ${{ steps.check_bot.outputs.latest_bot_review_id }}
          LATEST_BOT_REVIEW_COMMIT: ${{ steps.check_bot.outputs.latest_bot_review_commit }}
          IS_FOLLOW_UP_REVIEW: ${{ steps.check_bot.outputs.is_follow_up_review }}
        with:
          openai-api-key: ${{ secrets.OPENAI_API_KEY }}
          responses-api-endpoint: ${{ secrets.OPENAI_BASE_URL }}
          model: ${{ vars.OPENAI_MODEL || 'gpt-5.2-codex' }}
          effort: ${{ vars.OPENAI_EFFORT || 'high' }}
          sandbox: danger-full-access
          safety-strategy: drop-sudo
          prompt-file: .github/prompts/codex-pr-review.md
          allow-bots: true
          allow-users: "*"