# Copyright 2024 The Flutter Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

name: Remove outdated CICD Label

on:
  # This pull_request_target trigger is safe because the workflow does not checkout any untrusted code or execute code from the PR.
  # zizmor: ignore[dangerous-triggers]
  pull_request_target:
    types: [synchronize]

permissions:
  pull-requests: write
  issues: write

jobs:
  remove_cicd_label:
    if: contains(github.event.pull_request.labels.*.name, 'CICD')
    runs-on: ubuntu-latest
    steps:
      - name: Check if label was added before push
        id: check_timing
        run: |
          # Get push time (commit date of the head SHA)
          PUSH_TIME='${GITHUB_EVENT_PULL_REQUEST_UPDATED_AT}'
          echo "Push time: $PUSH_TIME"

          # Get latest CICD labeling event time from the last 100 events
          LABEL_TIME=$(gh api graphql -f query='
            query($owner: String!, $repo: String!, $pr: Int!) {
              repository(owner: $owner, name: $repo) {
                pullRequest(number: $pr) {
                  timelineItems(last: 100, itemTypes: [LABELED_EVENT]) {
                    nodes {
                      ... on LabeledEvent {
                        label { name }
                        createdAt
                      }
                    }
                  }
                }
              }
            }' -f owner=${{ github.repository_owner }} -f repo=${GITHUB_EVENT_REPOSITORY_NAME} -F pr=${{ github.event.pull_request.number }} \
            --jq '.data.repository.pullRequest.timelineItems.nodes | map(select(.label.name == "CICD")) | last | .createdAt')
          echo "Label time: $LABEL_TIME"

          if [[ -z "$LABEL_TIME" ]]; then
            # Label exists on PR (checked by job 'if') but not in last 100 events -> must be very old
            echo "should_remove=true" >> "$GITHUB_OUTPUT"
            echo "Result: Label found on PR but not in recent timeline events. Assuming it is old."
          elif [[ "$LABEL_TIME" < "$PUSH_TIME" ]]; then
            echo "should_remove=true" >> "$GITHUB_OUTPUT"
            echo "Result: Label added at $LABEL_TIME is older than push at $PUSH_TIME. Removing."
          else
            echo "should_remove=false" >> "$GITHUB_OUTPUT"
            echo "Result: Label added at $LABEL_TIME is newer than or same as push at $PUSH_TIME. Skipping removal."
          fi
        env:
          GH_TOKEN: ${{ github.token }}
          GITHUB_EVENT_PULL_REQUEST_UPDATED_AT: ${{ github.event.pull_request.updated_at }}
          GITHUB_EVENT_REPOSITORY_NAME: ${{ github.event.repository.name }}

      - name: Remove outdated CICD label
        if: steps.check_timing.outputs.should_remove == 'true'
        run: |
          gh pr edit ${{ github.event.pull_request.number }} -R ${{ github.repository }} --remove-label "CICD"
        env:
          GH_TOKEN: ${{ github.token }}