# Backfills duplicate detection for historical issues using Claude Code.
# Triggered manually via workflow_dispatch.
name: Backfill Duplicate Detection

on:
  workflow_dispatch:
    inputs:
      days_back:
        description: 'How many days back to look for issues (default: 30)'
        required: false
        default: '30'
        type: number

permissions:
  contents: read
  issues: write
  actions: write

jobs:
  backfill:
    runs-on: ubuntu-latest
    timeout-minutes: 10
    steps:
      - uses: actions/checkout@v4

      - name: Fetch issues and run dedupe
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          REPO: ${{ github.repository }}
          DAYS_BACK: ${{ inputs.days_back || '30' }}
        run: |
          if ! [[ "$DAYS_BACK" =~ ^[0-9]+$ ]]; then
            echo "Error: days_back must be a number"
            exit 1
          fi

          SINCE=$(date -u -d "$DAYS_BACK days ago" +%Y-%m-%dT%H:%M:%SZ 2>/dev/null || date -u -v-${DAYS_BACK}d +%Y-%m-%dT%H:%M:%SZ)
          echo "Fetching open issues since $SINCE"

          # Get open issues, filter out PRs and already-labeled ones
          ISSUES=$(gh issue list --repo "$REPO" --state open --limit 200 --json number,title,labels,createdAt \
            --jq "[.[] | select(.createdAt >= \"$SINCE\") | select([.labels[].name] | index(\"duplicate\") | not)] | .[].number")

          if [ -z "$ISSUES" ]; then
            echo "No issues to process"
            exit 0
          fi

          BATCH_SIZE=10
          COUNT=0
          echo "Issues to process: $ISSUES"
          for NUMBER in $ISSUES; do
            echo "Triggering dedupe for issue #$NUMBER"
            gh workflow run issue-dedupe.yml --repo "$REPO" -f issue_number="$NUMBER"
            COUNT=$((COUNT + 1))
            if [ $((COUNT % BATCH_SIZE)) -eq 0 ]; then
              echo "Pausing 60s after $COUNT issues..."
              sleep 60
            else
              sleep 5
            fi
          done

          echo "Backfill triggered for $COUNT issues"