# Mirror release assets to Cloudflare R2 so ccswitch.io/download can serve
# them directly (dl.ccswitch.io), and mirror the Tauri updater manifest and
# artifacts so in-app updates avoid GitHub too (the updater verifies minisign
# signatures client-side, so the mirror is untrusted).
#
# Triggered on release promotion (`released` fires when a prerelease is
# flipped to a full release, or a release is published as stable directly) —
# NOT on tag push. This keeps the R2 root manifests behind the same gate as
# GitHub's /releases/latest/: while a release sits as prerelease, neither the
# download page nor the updater sees it. Additionally, a run only touches the
# root manifests (and prunes old versions) when its tag IS releases/latest —
# manual backfills of older tags restore versioned files only.
#
# Caveat (by design of tauri-plugin-updater): the updater stops at the first
# endpoint whose response parses, so a stale-but-valid R2 manifest would mask
# newer GitHub releases. That is why this sync hard-fails on the official
# repo when the R2 secrets are missing, instead of silently skipping.
#
# Required secrets: R2_ACCOUNT_ID / R2_ACCESS_KEY_ID / R2_SECRET_ACCESS_KEY
name: Sync release to R2

on:
  release:
    types: [released]
  # Manual recovery/backfill: re-sync any existing release tag.
  workflow_dispatch:
    inputs:
      tag:
        description: 'Release tag to sync (e.g. v3.18.0)'
        required: true
        type: string

permissions:
  contents: read

# latest.json / manifest.json are last-writer-wins — serialize runs and keep
# every trigger queued instead of the default replace-the-pending behavior.
concurrency:
  group: sync-r2
  cancel-in-progress: false
  queue: max

jobs:
  sync-to-r2:
    name: Sync release to R2
    runs-on: ubuntu-22.04
    env:
      R2_BUCKET: cc-switch-releases
      R2_PUBLIC_BASE_URL: https://dl.ccswitch.io
      KEEP_VERSIONS: "5"
      AWS_ACCESS_KEY_ID: ${{ secrets.R2_ACCESS_KEY_ID }}
      AWS_SECRET_ACCESS_KEY: ${{ secrets.R2_SECRET_ACCESS_KEY }}
      AWS_DEFAULT_REGION: auto
      # aws-cli >= 2.23 defaults to CRC checksums that R2 rejects.
      AWS_REQUEST_CHECKSUM_CALCULATION: when_required
      AWS_RESPONSE_CHECKSUM_VALIDATION: when_required
      R2_ENDPOINT: https://${{ secrets.R2_ACCOUNT_ID }}.r2.cloudflarestorage.com
      TAG: ${{ github.event.release.tag_name || inputs.tag }}
    steps:
      - name: Check R2 secrets
        id: r2
        env:
          R2_ACCOUNT_ID: ${{ secrets.R2_ACCOUNT_ID }}
        run: |
          if [ -z "$TAG" ]; then
            echo "::error::No release tag to sync."
            exit 1
          fi
          if [ -n "$R2_ACCOUNT_ID" ] && [ -n "$AWS_ACCESS_KEY_ID" ] && [ -n "$AWS_SECRET_ACCESS_KEY" ]; then
            echo "configured=true" >> "$GITHUB_OUTPUT"
          elif [ "$GITHUB_REPOSITORY" = "farion1231/cc-switch" ]; then
            # A silently stale mirror strands updater users on old versions
            # (the R2 endpoint wins as long as its manifest parses), so the
            # official repo must never skip this sync.
            echo "::error::R2 secrets (R2_ACCOUNT_ID / R2_ACCESS_KEY_ID / R2_SECRET_ACCESS_KEY) are missing on the official repo; refusing to skip the mirror sync."
            exit 1
          else
            echo "configured=false" >> "$GITHUB_OUTPUT"
            echo "R2 secrets not configured; skipping download mirror sync."
          fi

      # Only the tag that IS GitHub's releases/latest may touch the bucket-root
      # manifests or prune old versions. This keeps manual backfills of old
      # tags harmless (they only restore versioned files — otherwise the root
      # manifests would point at a version the prune step deletes right after)
      # and makes out-of-order runs self-correcting: whichever run executes,
      # only the true latest publishes the manifests.
      - name: Check whether tag is the latest stable release
        id: latest
        if: steps.r2.outputs.configured == 'true'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -euo pipefail
          # An API failure must fail the run — mapping it to "not latest"
          # would skip the root manifests on a green run, silently leaving
          # them stale (the exact failure mode this workflow exists to make
          # loud). Retry transient errors, then give up loudly.
          latest=""
          for attempt in 1 2 3 4; do
            latest=$(gh api "repos/$GITHUB_REPOSITORY/releases/latest" --jq .tag_name || true)
            if [ -n "$latest" ]; then
              break
            fi
            if [ "$attempt" -lt 4 ]; then
              sleep $((attempt * 10))
            fi
          done
          if [ -z "$latest" ]; then
            echo "::error::Could not resolve the latest stable release from GitHub after 4 attempts; failing instead of guessing."
            exit 1
          fi
          if [ "$TAG" = "$latest" ]; then
            echo "is_latest=true" >> "$GITHUB_OUTPUT"
            echo "$TAG is the latest stable release; full sync."
          else
            echo "is_latest=false" >> "$GITHUB_OUTPUT"
            echo "::warning::$TAG is not the latest stable release ($latest); syncing versioned files only — root manifests and pruning are skipped."
          fi

      - name: Checkout scripts
        if: steps.r2.outputs.configured == 'true' && steps.latest.outputs.is_latest == 'true'
        uses: actions/checkout@v6
        with:
          sparse-checkout: scripts

      - name: Download release assets
        if: steps.r2.outputs.configured == 'true'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -euo pipefail
          mkdir -p r2-assets
          gh release download "$TAG" --dir r2-assets --repo "$GITHUB_REPOSITORY"
          ls -la r2-assets

      - name: Generate download manifest
        if: steps.r2.outputs.configured == 'true' && steps.latest.outputs.is_latest == 'true'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -euo pipefail
          pub_date=$(gh release view "$TAG" --repo "$GITHUB_REPOSITORY" --json publishedAt --jq .publishedAt)
          node scripts/generate-download-manifest.mjs r2-assets "$TAG" "$R2_PUBLIC_BASE_URL" manifest.json "$pub_date"

      - name: Rewrite updater manifest for R2
        if: steps.r2.outputs.configured == 'true' && steps.latest.outputs.is_latest == 'true'
        run: |
          set -euo pipefail
          node scripts/rewrite-updater-manifest.mjs r2-assets/latest.json "$TAG" "$R2_PUBLIC_BASE_URL" latest-r2.json

      - name: Upload versioned assets to R2
        if: steps.r2.outputs.configured == 'true'
        run: |
          set -euo pipefail
          # Versioned asset paths never change — cache hard at the edge.
          # .tar.gz is the macOS updater payload; .sig files are not needed
          # (signatures are embedded in latest.json) and latest.json goes to
          # the bucket root with a short TTL instead.
          aws s3 cp r2-assets "s3://$R2_BUCKET/$TAG/" \
            --recursive \
            --exclude "*.sig" --exclude "latest.json" \
            --cache-control "public, max-age=31536000, immutable" \
            --endpoint-url "$R2_ENDPOINT"

      - name: Publish root manifests to R2
        if: steps.r2.outputs.configured == 'true' && steps.latest.outputs.is_latest == 'true'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -euo pipefail
          # Re-verify right before touching the root manifests: a newer
          # release may have been promoted while assets were downloading.
          # Skipping then is safe — the newer release's own queued run
          # publishes the newer manifests. An unresolvable API is still a
          # hard failure, never a guess.
          latest=""
          for attempt in 1 2 3 4; do
            latest=$(gh api "repos/$GITHUB_REPOSITORY/releases/latest" --jq .tag_name || true)
            if [ -n "$latest" ]; then
              break
            fi
            if [ "$attempt" -lt 4 ]; then
              sleep $((attempt * 10))
            fi
          done
          if [ -z "$latest" ]; then
            echo "::error::Could not re-verify the latest stable release before publishing root manifests; failing instead of guessing."
            exit 1
          fi
          if [ "$TAG" != "$latest" ]; then
            echo "::warning::$TAG stopped being the latest stable release mid-run ($latest is); leaving root manifests untouched."
            exit 0
          fi
          # Both manifests are replaced on every release — keep edge cache
          # short. Uploaded after the assets they reference so an aborted run
          # never leaves them pointing at missing files.
          aws s3 cp manifest.json "s3://$R2_BUCKET/manifest.json" \
            --content-type "application/json" \
            --cache-control "public, max-age=300" \
            --endpoint-url "$R2_ENDPOINT"
          aws s3 cp latest-r2.json "s3://$R2_BUCKET/latest.json" \
            --content-type "application/json" \
            --cache-control "public, max-age=300" \
            --endpoint-url "$R2_ENDPOINT"

      - name: Prune old versions
        if: steps.r2.outputs.configured == 'true' && steps.latest.outputs.is_latest == 'true'
        run: |
          set -euo pipefail
          versions=$(aws s3 ls "s3://$R2_BUCKET/" --endpoint-url "$R2_ENDPOINT" \
            | awk '$1 == "PRE" {print $2}' | tr -d '/' | grep -E '^v[0-9]' | sort -V || true)
          count=$(printf '%s\n' "$versions" | grep -c . || true)
          if [ "$count" -le "$KEEP_VERSIONS" ]; then
            echo "Nothing to prune ($count versions, keeping up to $KEEP_VERSIONS)."
            exit 0
          fi
          printf '%s\n' "$versions" | head -n "-$KEEP_VERSIONS" | while read -r old; do
            [ -n "$old" ] || continue
            echo "Pruning s3://$R2_BUCKET/$old/"
            aws s3 rm "s3://$R2_BUCKET/$old/" --recursive --endpoint-url "$R2_ENDPOINT"
          done