# Pipeline auto assign current milestone for PR after the PR is merge
name: Assign Milestone
on:
  pull_request:
    types: [closed]

jobs:
  assign_milestone:
    runs-on: ubuntu-latest
    if: ${{ github.event.pull_request.head.repo.full_name == github.repository }}
    permissions:
      pull-requests: write
      issues: write
    steps:
      - name: Assign Milestone
        uses: actions/github-script@v3
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const { owner, repo } = context.repo;
            const { number, merged } = context.payload.pull_request;
            if (merged) {
              const { data: milestones } = await github.issues.listMilestones({
                owner,
                repo,
                state: 'open',
              });

              const mergedDate = new Date(context.payload.pull_request.merged_at);
              const currentMilestone = milestones
              .filter(milestone => milestone.due_on !== null)
              .find((milestone) => {
                const dueDate = new Date(milestone.due_on);
                return mergedDate <= dueDate;
              });

              if (currentMilestone) {
                await github.issues.update({
                  owner,
                  repo,
                  issue_number: number,
                  milestone: currentMilestone.number
                });
              }
            }
          debug: true