name: Bot Cleanup

# Two ingress paths:
#  - issues.closed: drop the bot branches for that issue immediately.
#  - daily cron:    sweep `bot/artifacts-*` branches older than 90 days.
#
# Both jobs use the app token so deletions land as the bot identity (not
# whoever closed the issue).

on:
  issues:
    types: [closed]
  schedule:
    # 04:00 UTC daily. Off-peak for most contributors.
    - cron: "0 4 * * *"

permissions:
  contents: read

concurrency:
  group: bot-cleanup
  cancel-in-progress: false

jobs:
  cleanup-on-close:
    name: Delete bot branches when an issue closes
    if: github.event_name == 'issues' && github.event.issue.pull_request == null
    runs-on: ubuntu-latest
    timeout-minutes: 5
    permissions:
      contents: read
    steps:
      - name: Generate app token
        id: app-token
        uses: actions/create-github-app-token@bcd2ba49218906704ab6c1aa796996da409d3eb1 # v3.2.0
        with:
          app-id: ${{ secrets.APP_ID }}
          private-key: ${{ secrets.APP_PRIVATE_KEY }}
          owner: emdash-cms
          repositories: emdash
          permission-contents: write
          # Read-only PR scope so we can `gh pr list --head bot/fix-N`
          # before deleting the branch -- protects an open bot-opened
          # PR from being orphaned when an issue is closed without
          # merging.
          permission-pull-requests: read

      - name: Delete bot branches for closed issue
        env:
          GH_TOKEN: ${{ steps.app-token.outputs.token }}
          ISSUE_NUMBER: ${{ github.event.issue.number }}
        run: |
          set -euo pipefail
          FIX_BRANCH="bot/fix-${ISSUE_NUMBER}"
          ART_BRANCH="bot/artifacts-${ISSUE_NUMBER}"

          # bot/fix-N MAY have an open PR pointing at it (the bot
          # opens one after `triage/verified`). Deleting the ref would
          # invalidate that PR. Two close paths to worry about:
          #
          #  - PR merged -> issue auto-closes via "Closes #N" -> we
          #    fire here. The PR is closed; deleting the now-unused
          #    ref is fine. GitHub may have already deleted it.
          #  - Maintainer manually closes the issue ("won't fix",
          #    "stale", etc.) while the bot PR is still open. We
          #    must NOT delete the ref -- it would close the PR
          #    silently and lose the bot's work with no recovery.
          OPEN_PR_COUNT="$(gh pr list \
            --repo emdash-cms/emdash \
            --head "$FIX_BRANCH" \
            --state open \
            --json number \
            --jq 'length' 2>/dev/null || echo 0)"

          if [[ "$OPEN_PR_COUNT" != "0" ]]; then
            echo "::notice::skipping ${FIX_BRANCH} deletion: ${OPEN_PR_COUNT} open PR(s) reference it"
          else
            ENCODED="${FIX_BRANCH//\//%2F}"
            STATUS="$(gh api -X DELETE "repos/emdash-cms/emdash/git/refs/heads/${ENCODED}" \
              --silent -i 2>/dev/null | head -n 1 || true)"
            echo "DELETE ${FIX_BRANCH}: ${STATUS:-no response}"
          fi

          # bot/artifacts-N is never the head of any PR (it's an
          # orphan branch with screenshots only). Always safe to delete.
          ENCODED="${ART_BRANCH//\//%2F}"
          STATUS="$(gh api -X DELETE "repos/emdash-cms/emdash/git/refs/heads/${ENCODED}" \
            --silent -i 2>/dev/null | head -n 1 || true)"
          echo "DELETE ${ART_BRANCH}: ${STATUS:-no response}"

  cleanup-daily:
    name: Prune stale artifact branches
    if: github.event_name == 'schedule'
    runs-on: ubuntu-latest
    timeout-minutes: 15
    permissions:
      contents: read
    steps:
      - name: Generate app token
        id: app-token
        uses: actions/create-github-app-token@bcd2ba49218906704ab6c1aa796996da409d3eb1 # v3.2.0
        with:
          app-id: ${{ secrets.APP_ID }}
          private-key: ${{ secrets.APP_PRIVATE_KEY }}
          owner: emdash-cms
          repositories: emdash
          permission-contents: write

      - name: Sweep stale artifacts branches
        env:
          GH_TOKEN: ${{ steps.app-token.outputs.token }}
        run: |
          set -euo pipefail
          CUTOFF="$(date -u -d '90 days ago' +%s 2>/dev/null || date -u -v-90d +%s)"
          # Paginated branch list; filter to bot/artifacts-* in jq.
          BRANCHES="$(gh api "repos/emdash-cms/emdash/branches" --paginate \
            --jq '.[] | select(.name | startswith("bot/artifacts-")) | .name')"
          if [[ -z "$BRANCHES" ]]; then
            echo "No bot/artifacts-* branches found."
            exit 0
          fi
          while IFS= read -r NAME; do
            [[ -z "$NAME" ]] && continue
            ENCODED="${NAME//\//%2F}"
            DATE="$(gh api "repos/emdash-cms/emdash/branches/${ENCODED}" \
              --jq '.commit.commit.committer.date' 2>/dev/null || true)"
            if [[ -z "$DATE" ]]; then
              echo "Skipping ${NAME}: could not read commit date."
              continue
            fi
            TS="$(date -u -d "$DATE" +%s 2>/dev/null || date -u -j -f '%Y-%m-%dT%H:%M:%SZ' "$DATE" +%s)"
            if (( TS < CUTOFF )); then
              echo "Deleting ${NAME} (committed ${DATE})"
              gh api -X DELETE "repos/emdash-cms/emdash/git/refs/heads/${ENCODED}" --silent || \
                echo "  delete failed for ${NAME} (already gone?)"
            else
              echo "Keeping ${NAME} (committed ${DATE})"
            fi
          done <<<"$BRANCHES"