name: release

# Triggers on semver tag push (v0.1.0, v0.1.1, etc.). Builds release
# artifacts for x86_64 and arm64, then publishes them on a GitHub
# Release matching the tag.
#
# Maintainer flow:
#   git tag v0.1.0
#   git push origin v0.1.0
#   → CI builds + publishes release with skeletonkey-x86_64 + skeletonkey-arm64

on:
  push:
    tags: ['v*.*.*']
  workflow_dispatch:   # allow manual re-runs

permissions:
  contents: write      # needed by softprops/action-gh-release

jobs:
  build:
    strategy:
      fail-fast: false
      matrix:
        include:
          - target: x86_64
            cc: gcc
            apt: build-essential
          - target: arm64
            cc: aarch64-linux-gnu-gcc
            apt: build-essential gcc-aarch64-linux-gnu libc6-dev-arm64-cross linux-libc-dev-arm64-cross
    name: build (${{ matrix.target }})
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: install build deps
        run: |
          sudo apt-get update -qq
          sudo apt-get install -y --no-install-recommends ${{ matrix.apt }} linux-libc-dev

      - name: build
        env:
          CC: ${{ matrix.cc }}
        run: |
          make
          file skeletonkey
          ls -la skeletonkey

      - name: rename + checksum
        run: |
          mv skeletonkey skeletonkey-${{ matrix.target }}
          sha256sum skeletonkey-${{ matrix.target }} > skeletonkey-${{ matrix.target }}.sha256

      - uses: actions/upload-artifact@v4
        with:
          name: skeletonkey-${{ matrix.target }}
          path: |
            skeletonkey-${{ matrix.target }}
            skeletonkey-${{ matrix.target }}.sha256

  # Portable static-musl x86_64 build. Runs in Alpine (native musl +
  # linux-headers) so the resulting binary works on every libc —
  # glibc 2.x of any version, musl, etc. This is what install.sh
  # fetches by default for x86_64 hosts (the dynamic binary above
  # hits a glibc-version ceiling on older distros like Debian 12 /
  # RHEL 8).
  build-static-x86_64:
    runs-on: ubuntu-latest
    name: build (x86_64-static / musl)
    container:
      image: alpine:latest
    steps:
      - uses: actions/checkout@v4
      - name: install build deps
        run: apk add --no-cache build-base linux-headers tar
      - name: build static (musl)
        run: |
          # MSG_COPY is a Linux-only SysV msg flag that glibc defines
          # but musl does not — netfilter_xtcompat needs it. Define
          # the kernel constant explicitly. (Kernel: include/uapi/
          # linux/msg.h: MSG_COPY = 040000)
          make CFLAGS="-O2 -Wall -Wextra -Wno-unused-parameter -Wno-pointer-arith -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -DMSG_COPY=040000" LDFLAGS=-static
          file skeletonkey
          ls -la skeletonkey
      - name: rename + checksum
        run: |
          mv skeletonkey skeletonkey-x86_64-static
          sha256sum skeletonkey-x86_64-static > skeletonkey-x86_64-static.sha256
      - uses: actions/upload-artifact@v4
        with:
          name: skeletonkey-x86_64-static
          path: |
            skeletonkey-x86_64-static
            skeletonkey-x86_64-static.sha256

  # Portable static-musl arm64 build. Cross-compile from the x86_64
  # runner using dockcross/linux-arm64-musl — a Debian-based cross
  # toolchain image that ships aarch64-linux-musl-gcc with a clean
  # musl sysroot + Linux uapi headers. Avoids the two prior failure
  # modes:
  #   (1) Alpine on arm64: actions/checkout JS bundle requires glibc-
  #       compatible Node, which GitHub doesn't inject on arm64.
  #   (2) musl-tools on ubuntu-24.04-arm: musl-gcc + Ubuntu's
  #       /usr/include collide (glibc stdio.h vs musl stdio.h →
  #       __gnuc_va_list / __time64_t conflicts).
  # dockcross runs glibc Debian (so checkout works), invokes a
  # bundled aarch64-linux-musl-gcc whose sysroot has its own
  # consistent musl + linux-uapi tree.
  build-static-arm64:
    runs-on: ubuntu-latest
    name: build (arm64-static / musl)
    steps:
      - uses: actions/checkout@v4
      - name: run dockcross arm64-musl build
        run: |
          # Fetch the dockcross wrapper script (handles UID/GID,
          # volume mounts, env passing). Image already has
          # aarch64-linux-musl-gcc on PATH.
          docker run --rm dockcross/linux-arm64-musl > ./dockcross
          chmod +x ./dockcross
          ./dockcross bash -c '
            make CC=aarch64-linux-musl-gcc \
                 CFLAGS="-O2 -Wall -Wextra -Wno-unused-parameter -Wno-pointer-arith -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -DMSG_COPY=040000" \
                 LDFLAGS=-static
          '
          file skeletonkey
          ls -la skeletonkey
      - name: rename + checksum
        run: |
          mv skeletonkey skeletonkey-arm64-static
          sha256sum skeletonkey-arm64-static > skeletonkey-arm64-static.sha256
      - uses: actions/upload-artifact@v4
        with:
          name: skeletonkey-arm64-static
          path: |
            skeletonkey-arm64-static
            skeletonkey-arm64-static.sha256

  release:
    needs: [build, build-static-x86_64, build-static-arm64]
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - uses: actions/download-artifact@v4
        with:
          path: dist

      - name: flatten artifacts
        run: |
          find dist -type f -exec mv {} . \;
          ls -la skeletonkey-*

      - name: collect release notes
        id: notes
        run: |
          tag="${GITHUB_REF#refs/tags/}"
          echo "tag=$tag" >> "$GITHUB_OUTPUT"
          # Prefer the hand-written release notes if present (richer
          # per-release context); otherwise fall back to an auto-generated
          # stub with install instructions + pointers to docs.
          if [ -f docs/RELEASE_NOTES.md ]; then
            cp docs/RELEASE_NOTES.md release-notes.md
          else
            {
              echo "## SKELETONKEY $tag"
              echo
              echo "Pre-built binaries for x86_64 (dynamic + static-musl) and arm64."
              echo "Checksums alongside each artifact."
              echo
              echo "### Install"
              echo '```bash'
              echo "curl -sSL https://github.com/${GITHUB_REPOSITORY}/releases/download/${tag}/install.sh | sh"
              echo "skeletonkey --version"
              echo '```'
              echo
              echo "See [\`CVES.md\`](https://github.com/${GITHUB_REPOSITORY}/blob/${tag}/CVES.md) for the CVE inventory."
              echo "See [\`docs/RELEASE_NOTES.md\`](https://github.com/${GITHUB_REPOSITORY}/blob/${tag}/docs/RELEASE_NOTES.md) for per-release detail."
            } > release-notes.md
          fi

      - name: publish release
        uses: softprops/action-gh-release@v2
        with:
          tag_name: ${{ steps.notes.outputs.tag }}
          name: SKELETONKEY ${{ steps.notes.outputs.tag }}
          body_path: release-notes.md
          files: |
            skeletonkey-x86_64
            skeletonkey-x86_64.sha256
            skeletonkey-x86_64-static
            skeletonkey-x86_64-static.sha256
            skeletonkey-arm64
            skeletonkey-arm64.sha256
            skeletonkey-arm64-static
            skeletonkey-arm64-static.sha256
            install.sh
          fail_on_unmatched_files: false   # install.sh may not exist at first tag