name: Weekly channel health trend

on:
  schedule:
    - cron: '0 6 * * 1'  # every Monday 06:00 UTC
  workflow_dispatch:

jobs:
  trend:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v6

      - name: Setup Node
        uses: actions/setup-node@v6
        with:
          node-version: "20.10.x"

      - name: Install IPTV Checker
        run: |
          npm install -g iptv-checker || true
          sudo apt-get update && sudo apt-get install -y ffmpeg

      - name: Download last week's snapshot (if any)
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          mkdir -p prev_snapshot
          prev_run=$(gh run list --repo "${{ github.repository }}" --workflow weekly_trend.yml --status success --limit 1 --json databaseId -q '.[0].databaseId' || true)
          if [ -n "$prev_run" ]; then
            echo "Found previous successful run: $prev_run"
            gh run download "$prev_run" --repo "${{ github.repository }}" -n checker-history -D prev_snapshot || echo "No artifact on that run (probably the very first one)."
          else
            echo "No previous successful run found — this is the first run."
          fi

      - name: Run checker against the full playlist
        run: |
          mkdir -p output
          iptv-checker -o output -p 100 -t 120000 ./playlist.m3u8 || true

      - name: Compare against last week's snapshot
        run: |
          mkdir -p snapshot
          curr_file="snapshot/failed.txt"
          prev_file="prev_snapshot/failed.txt"

          grep '^http' output/failed.m3u 2>/dev/null | sort -u > "$curr_file" || touch "$curr_file"

          online=$(grep -c '^#EXTINF' output/online.m3u 2>/dev/null || echo 0)
          failed=$(grep -c '^#EXTINF' output/failed.m3u 2>/dev/null || echo 0)

          {
            echo "## Weekly channel health trend — $(date -u +%Y-%m-%d)"
            echo ""
            echo "- Online: $online"
            echo "- Failed: $failed"
            echo ""
          } >> "$GITHUB_STEP_SUMMARY"

          if [ -s "$prev_file" ]; then
            newly_failed=$(comm -13 "$prev_file" "$curr_file")
            newly_fixed=$(comm -23 "$prev_file" "$curr_file")
            nf_count=$(printf '%s\n' "$newly_failed" | grep -c . || true)
            nx_count=$(printf '%s\n' "$newly_fixed" | grep -c . || true)
            {
              echo "### Changes since last snapshot"
              echo "- Newly broken: $nf_count"
              echo "- Recovered / fixed since then: $nx_count"
              if [ "$nf_count" -gt 0 ]; then
                echo ""
                echo "**Newly broken URLs:**"
                echo '```'
                printf '%s\n' "$newly_failed"
                echo '```'
              fi
              if [ "$nx_count" -gt 0 ]; then
                echo ""
                echo "**Recovered URLs (were failing, now online):**"
                echo '```'
                printf '%s\n' "$newly_fixed"
                echo '```'
              fi
            } >> "$GITHUB_STEP_SUMMARY"
          else
            echo "_(no previous snapshot — this is the first run, nothing to compare against yet)_" >> "$GITHUB_STEP_SUMMARY"
          fi

      - name: Upload this week's snapshot for next time
        uses: actions/upload-artifact@v4
        with:
          name: checker-history
          path: snapshot/failed.txt
          retention-days: 90