name: Publish sidecars to R2

# Publishes the `donut-proxy` sidecar to the bucket behind
# https://download.wayfern.com, where remote hosts fetch it from.
#
# WHY THIS EXISTS SEPARATELY FROM release.yml
# The desktop app ships donut-proxy INSIDE the bundle as a Tauri sidecar, so a
# desktop release never needs it in a bucket. Remote execution is the opposite:
# a remote host has no bundle and cannot launch a browser without the sidecar.
# Tying publication to a desktop release would mean remote execution could only
# be unblocked by cutting one.
#
# Only three targets are needed here. Everything else gets its sidecar from the
# app bundle and is deliberately not built.

on:
  workflow_dispatch:
    inputs:
      ref:
        description: "Git ref to build from (defaults to the triggering ref)"
        required: false
        type: string
  push:
    branches: [main]
    paths:
      # The proxy is a separate bin from the app, and republishing invalidates
      # the SHA an operator recorded out of band — so this is narrowed to the
      # modules `src/bin/proxy_server.rs` actually imports, rather than all of
      # src-tauri/src.
      #
      # BEST EFFORT, deliberately: the bin reaches donutbrowser_lib, so a change
      # deep in a shared module can alter the binary without matching a path
      # here. `workflow_dispatch` is the escape hatch, and the round-trip digest
      # check means a stale publish is visible rather than silent.
      - "src-tauri/src/bin/proxy_server.rs"
      - "src-tauri/src/proxy_server.rs"
      - "src-tauri/src/proxy_storage.rs"
      - "src-tauri/src/proxy_runner.rs"
      - "src-tauri/src/socks5_local.rs"
      - "src-tauri/src/app_dirs.rs"
      - "src-tauri/src/vpn/**"
      - "src-tauri/src/vpn_worker_storage.rs"
      - "src-tauri/src/xray_worker_runner.rs"
      - "src-tauri/src/xray/**"
      - "src-tauri/build.rs"
      - "src-tauri/Cargo.toml"
      - "src-tauri/Cargo.lock"
      - ".github/workflows/publish-sidecars.yml"

concurrency:
  # Two overlapping runs would race on the same object keys and the loser's
  # bytes could win, leaving the bucket serving a build nobody recorded.
  group: publish-sidecars
  cancel-in-progress: false

permissions:
  contents: read

jobs:
  build:
    name: Build donut-proxy (${{ matrix.target }})
    runs-on: ${{ matrix.platform }}
    strategy:
      # One target failing must not leave the others unpublished and the set
      # skewed; publish what built and report the rest.
      fail-fast: false
      matrix:
        include:
          # macOS arm64 remote host.
          - platform: macos-latest
            target: aarch64-apple-darwin
            artifact: donut-proxy-aarch64-apple-darwin
          # Windows x86_64 remote host.
          - platform: windows-latest
            target: x86_64-pc-windows-msvc
            artifact: donut-proxy-x86_64-pc-windows-msvc.exe
          # Linux x86_64 remote host. Pinned to 22.04, not -latest: the
          # deployment target is glibc 2.35, and a binary linked on 24.04
          # (glibc 2.39) refuses to load there. The stage step proves the pin
          # held.
          - platform: ubuntu-22.04
            target: x86_64-unknown-linux-gnu
            artifact: donut-proxy-x86_64-unknown-linux-gnu

    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
        with:
          ref: ${{ inputs.ref || github.ref }}
          # build.rs derives BUILD_VERSION from git; a shallow clone with no tags
          # makes every published binary report `nightly-<hash>` instead of a
          # version, which is what an operator reads to tell builds apart.
          fetch-depth: 0

      - name: Install Rust
        uses: dtolnay/rust-toolchain@6c977a6ca4077a0ceb28ffbe03f59d46e9ac8772 # master
        with:
          toolchain: stable
          targets: ${{ matrix.target }}

      # The proxy bin links donutbrowser_lib, which pulls in Tauri and therefore
      # GTK and WebKit at link time even though the proxy never opens a window.
      # Same package list as release.yml, so the two cannot drift apart.
      - name: Install Linux build dependencies
        if: runner.os == 'Linux'
        run: |
          sudo apt-get update
          sudo apt-get install -y libwebkit2gtk-4.1-dev libgtk-3-dev libayatana-appindicator3-dev librsvg2-dev libxdo-dev pkg-config unzip xdg-utils

      - name: Build donut-proxy
        shell: bash
        working-directory: ./src-tauri
        env:
          GITHUB_REF_NAME: ${{ github.ref_name }}
        run: cargo build --bin donut-proxy --target ${{ matrix.target }} --release

      - name: Stage the binary and record its digest
        id: stage
        shell: bash
        working-directory: ./src-tauri
        run: |
          set -euo pipefail
          mkdir -p "$RUNNER_TEMP/sidecars"
          src="target/${{ matrix.target }}/release/donut-proxy"
          [ -f "$src.exe" ] && src="$src.exe"
          if [ ! -f "$src" ]; then
            echo "::error::cargo reported success but $src does not exist"
            exit 1
          fi
          dest="$RUNNER_TEMP/sidecars/${{ matrix.artifact }}"
          cp "$src" "$dest"
          chmod +x "$dest"

          # Prove the thing we are about to publish actually runs and is the
          # binary we think it is. A sidecar that cannot start is indistinguishable
          # from a missing one once it is on a remote host, except that it fails
          # later and less clearly.
          version="$("$dest" --version)"
          case "$version" in
            "donut-proxy "*) ;;
            *) echo "::error::unexpected --version output: $version"; exit 1 ;;
          esac

          if [ "$RUNNER_OS" = "Linux" ]; then
            # The Linux deployment target is glibc 2.35. A binary linked on a
            # newer runner fails there with "version GLIBC_2.xx not found",
            # which reaches the host only as a sidecar that "will not run".
            # The runner is pinned to 22.04 for that reason; this proves the
            # pin held, and that every library the binary names resolves at
            # all.
            fleet_glibc_max=2.35
            if ! ldd_out="$(ldd "$dest")"; then
              echo "::error::ldd cannot read $dest"
              printf '%s\n' "$ldd_out"
              exit 1
            fi
            if grep -q 'not found' <<< "$ldd_out"; then
              echo "::error::$dest needs a shared library this runner cannot resolve, and the fleet host will not either"
              printf '%s\n' "$ldd_out"
              exit 1
            fi
            needed="$(objdump -p "$dest" | awk '$1 == "NEEDED" { print $2 }')"
            glibc_max="$(objdump -T "$dest" | grep -o 'GLIBC_[0-9]*\.[0-9]*' | sed 's/^GLIBC_//' | sort -uV | tail -n 1)"
            if [ -z "$glibc_max" ]; then
              echo "::error::could not read the glibc symbol versions of $dest"
              exit 1
            fi
            {
              echo "### ${{ matrix.artifact }} shared libraries (DT_NEEDED)"
              echo ""
              echo '```'
              printf '%s\n' "$needed"
              echo '```'
              echo ""
              echo "- highest glibc symbol version: \`GLIBC_$glibc_max\` (fleet host ceiling: \`GLIBC_$fleet_glibc_max\`)"
              echo ""
            } >> "$GITHUB_STEP_SUMMARY"
            if [ "$(printf '%s\n' "$glibc_max" "$fleet_glibc_max" | sort -V | tail -n 1)" != "$fleet_glibc_max" ]; then
              echo "::error::$dest needs GLIBC_$glibc_max, but the fleet host (Ubuntu 22.04) ships glibc $fleet_glibc_max; build it on ubuntu-22.04"
              exit 1
            fi
          fi

          if command -v sha256sum >/dev/null; then
            digest="$(sha256sum "$dest" | cut -d' ' -f1)"
          else
            digest="$(shasum -a 256 "$dest" | cut -d' ' -f1)"
          fi

          echo "digest=$digest" >> "$GITHUB_OUTPUT"
          echo "version=$version" >> "$GITHUB_OUTPUT"
          printf '%s  %s\n' "$digest" "${{ matrix.artifact }}" \
            > "$RUNNER_TEMP/sidecars/${{ matrix.artifact }}.sha256"

      - name: Publish to R2
        shell: bash
        env:
          # The repo's existing R2 secrets (see publish-repos.yml) are preferred;
          # the AWS_* names are accepted because R2's S3 API is what those
          # credentials are for and an operator may have configured either.
          R2_ACCESS_KEY_ID: ${{ secrets.R2_ACCESS_KEY_ID }}
          R2_SECRET_ACCESS_KEY: ${{ secrets.R2_SECRET_ACCESS_KEY }}
          AWS_KEY_FALLBACK: ${{ secrets.AWS_ACCESS_KEY_ID }}
          AWS_SECRET_FALLBACK: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
          R2_ENDPOINT_URL: ${{ secrets.R2_ENDPOINT_URL }}
          CLOUDFLARE_ACCOUNT_ID: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
          # The bucket behind download.wayfern.com. Defaulted rather than
          # required so this works with the account's existing setup.
          WAYFERN_R2_BUCKET: ${{ secrets.WAYFERN_R2_BUCKET }}
          ARTIFACT: ${{ matrix.artifact }}
          DIGEST: ${{ steps.stage.outputs.digest }}
        run: |
          set -euo pipefail

          if ! command -v aws >/dev/null; then
            # Preinstalled on every GitHub-hosted image, so its absence means a
            # self-hosted or changed runner. Say that, rather than failing later
            # with "command not found" from inside a chain of pipes.
            echo "::error::aws CLI not found on this runner. Install aws-cli v2 or use a GitHub-hosted runner."
            exit 1
          fi

          # Byte-identical to publish-repos.yml. Deliberately NOT a `tr -d` of
          # quote characters: that would corrupt a secret containing one, rather
          # than only unwrapping a value someone pasted with quotes around it.
          strip() { printf '%s' "$1" | tr -d '\r\n' | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//' -e 's/^"\(.*\)"$/\1/' -e "s/^'\(.*\)'\$/\1/"; }

          key_id="$(strip "${R2_ACCESS_KEY_ID:-}")"
          secret="$(strip "${R2_SECRET_ACCESS_KEY:-}")"
          if [ -z "$key_id" ] || [ -z "$secret" ]; then
            key_id="$(strip "${AWS_KEY_FALLBACK:-}")"
            secret="$(strip "${AWS_SECRET_FALLBACK:-}")"
          fi
          if [ -z "$key_id" ] || [ -z "$secret" ]; then
            echo "::error::No R2 credentials. Set R2_ACCESS_KEY_ID + R2_SECRET_ACCESS_KEY (preferred) or AWS_ACCESS_KEY_ID + AWS_SECRET_ACCESS_KEY as repository secrets."
            exit 1
          fi

          bucket="$(strip "${WAYFERN_R2_BUCKET:-}")"
          bucket="${bucket:-wayfern}"

          endpoint="$(strip "${R2_ENDPOINT_URL:-}")"
          if [ -z "$endpoint" ]; then
            account="$(strip "${CLOUDFLARE_ACCOUNT_ID:-}")"
            if [ -z "$account" ]; then
              echo "::error::Set R2_ENDPOINT_URL, or CLOUDFLARE_ACCOUNT_ID so the endpoint can be derived."
              exit 1
            fi
            endpoint="https://${account}.r2.cloudflarestorage.com"
          fi
          case "$endpoint" in https://*) ;; *) endpoint="https://$endpoint" ;; esac

          export AWS_ACCESS_KEY_ID="$key_id"
          export AWS_SECRET_ACCESS_KEY="$secret"
          export AWS_DEFAULT_REGION="auto"
          # aws-cli v2.23+ sends integrity checksums by default and R2 rejects
          # them with `Unauthorized`. Same workaround as scripts/publish-repo.sh.
          export AWS_REQUEST_CHECKSUM_CALCULATION="WHEN_REQUIRED"
          export AWS_RESPONSE_CHECKSUM_VALIDATION="WHEN_REQUIRED"

          src="$RUNNER_TEMP/sidecars/$ARTIFACT"

          # no-cache, not a long max-age: this key is deliberately overwritten in
          # place, and a cached copy of the previous build would make a host
          # fail its integrity check, which reads as a corrupt download rather
          # than a stale cache.
          aws s3 cp "$src" "s3://${bucket}/${ARTIFACT}" \
            --endpoint-url "$endpoint" \
            --content-type application/octet-stream \
            --cache-control "no-cache, must-revalidate" \
            --only-show-errors
          aws s3 cp "$src.sha256" "s3://${bucket}/${ARTIFACT}.sha256" \
            --endpoint-url "$endpoint" \
            --content-type text/plain \
            --cache-control "no-cache, must-revalidate" \
            --only-show-errors

          # Read it back and compare. Without this, "published" is an assumption:
          # a truncated upload or a write to the wrong bucket both look like
          # success, and the failure would surface days later on a remote host
          # as an unexplained checksum mismatch.
          verify="$RUNNER_TEMP/verify-$ARTIFACT"
          aws s3 cp "s3://${bucket}/${ARTIFACT}" "$verify" \
            --endpoint-url "$endpoint" --only-show-errors
          if command -v sha256sum >/dev/null; then
            got="$(sha256sum "$verify" | cut -d' ' -f1)"
          else
            got="$(shasum -a 256 "$verify" | cut -d' ' -f1)"
          fi
          if [ "$got" != "$DIGEST" ]; then
            echo "::error::Round-trip mismatch for $ARTIFACT: uploaded $DIGEST, bucket returned $got"
            exit 1
          fi
          echo "Published and verified $ARTIFACT ($DIGEST)"

      - name: Summarise
        if: always() && steps.stage.outputs.digest != ''
        shell: bash
        env:
          ARTIFACT: ${{ matrix.artifact }}
          DIGEST: ${{ steps.stage.outputs.digest }}
          VERSION: ${{ steps.stage.outputs.version }}
        run: |
          {
            echo "### $ARTIFACT"
            echo ""
            echo "- version: \`$VERSION\`"
            echo "- sha256: \`$DIGEST\`"
            echo "- url: https://download.wayfern.com/$ARTIFACT"
            echo ""
            echo "The fleet bootstrap takes this digest as an argument, so copy it"
            echo "from here rather than fetching the published \`.sha256\` — a hash"
            echo "served by the same bucket as the binary verifies transport only."
          } >> "$GITHUB_STEP_SUMMARY"