name: Rust Setup + Sccache
description: Install Rust and configure sccache for Rust builds in Gitea Actions
author: eric

inputs:
  toolchain:
    description: Rust toolchain to install (e.g., stable, 1.75.0, nightly)
    default: stable
    required: false
  sccache:
    description: Enable sccache and set RUSTC_WRAPPER.
    default: "true"
    required: false
  sccache-version:
    description: Mozilla sccache release tag to install.
    default: v0.15.0
    required: false
  sccache-bucket:
    description: S3 bucket for sccache. Leave empty to use local sccache storage.
    default: ""
    required: false
  sccache-region:
    description: S3 region. Use auto for S3-compatible services when an endpoint is provided.
    default: auto
    required: false
  sccache-endpoint:
    description: Optional S3-compatible endpoint URL, for example https://s3.example.com.
    default: ""
    required: false
  sccache-s3-use-ssl:
    description: Whether the S3 endpoint uses TLS.
    default: "true"
    required: false
  sccache-s3-enable-virtual-host-style:
    description: Enable virtual-host-style S3 addressing.
    default: "false"
    required: false
  sccache-key-prefix:
    description: Optional S3 key prefix. Defaults to repository/runner/toolchain scope.
    default: ""
    required: false
  sccache-wrap-cc:
    description: Also wrap CC and CXX with sccache so build-script C/C++ compiles (e.g. libduckdb-sys, ring) hit the same cache as rustc. Set to "false" to opt out.
    default: "true"
    required: false

outputs:
  sccache-enabled:
    description: Whether sccache was enabled.
    value: ${{ steps.configure-sccache.outputs.enabled }}

runs:
  using: composite
  steps:
    - name: Setup Rust
      shell: bash
      run: |
        curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs \
          | sh -s -- -y --profile minimal --default-toolchain '${{ inputs.toolchain }}'
        echo "$HOME/.cargo/bin" >> "$GITHUB_PATH"

    - name: Install sccache
      if: ${{ inputs.sccache == 'true' }}
      shell: bash
      run: |
        set -euo pipefail
        version='${{ inputs.sccache-version }}'
        case "$(uname -s)-$(uname -m)" in
          Linux-x86_64) target=x86_64-unknown-linux-musl ;;
          Linux-aarch64|Linux-arm64) target=aarch64-unknown-linux-musl ;;
          Darwin-x86_64) target=x86_64-apple-darwin ;;
          Darwin-arm64|Darwin-aarch64) target=aarch64-apple-darwin ;;
          *)
            echo "unsupported sccache platform: $(uname -s)-$(uname -m)" >&2
            exit 1
            ;;
        esac
        asset="sccache-${version}-${target}.tar.gz"
        base_url="https://github.com/mozilla/sccache/releases/download/${version}"
        tmp="$(mktemp -d)"
        trap 'rm -rf "$tmp"' EXIT
        curl -fsSLo "$tmp/$asset" "$base_url/$asset"
        curl -fsSLo "$tmp/$asset.sha256" "$base_url/$asset.sha256"
        expected="$(tr -d '[:space:]' < "$tmp/$asset.sha256")"
        if command -v sha256sum >/dev/null 2>&1; then
          actual="$(sha256sum "$tmp/$asset" | cut -d ' ' -f 1)"
        else
          actual="$(shasum -a 256 "$tmp/$asset" | cut -d ' ' -f 1)"
        fi
        test "$expected" = "$actual"
        tar -xzf "$tmp/$asset" -C "$tmp"
        install -m 755 "$(find "$tmp" -type f -name sccache | head -n 1)" "$HOME/.cargo/bin/sccache"
        sccache --version

    - name: Configure sccache
      id: configure-sccache
      if: ${{ inputs.sccache == 'true' }}
      shell: bash
      run: |
        set -euo pipefail
        echo "enabled=true" >> "$GITHUB_OUTPUT"
        echo "RUSTC_WRAPPER=sccache" >> "$GITHUB_ENV"
        echo "CARGO_INCREMENTAL=0" >> "$GITHUB_ENV"
        echo "SCCACHE_IGNORE_SERVER_IO_ERROR=1" >> "$GITHUB_ENV"
        echo "SCCACHE_IDLE_TIMEOUT=3600" >> "$GITHUB_ENV"
        echo "SCCACHE_LOG=${SCCACHE_LOG:-warn}" >> "$GITHUB_ENV"
        if [ -n '${{ inputs.sccache-bucket }}' ]; then
          repo="${GITHUB_REPOSITORY:-unknown/repository}"
          runner_os="${RUNNER_OS:-$(uname -s)}"
          runner_arch="${RUNNER_ARCH:-$(uname -m)}"
          prefix='${{ inputs.sccache-key-prefix }}'
          if [ -z "$prefix" ]; then
            prefix="$repo/$runner_os-$runner_arch/${{ inputs.toolchain }}"
          fi
          echo "SCCACHE_BUCKET=${{ inputs.sccache-bucket }}" >> "$GITHUB_ENV"
          echo "SCCACHE_REGION=${{ inputs.sccache-region }}" >> "$GITHUB_ENV"
          echo "SCCACHE_S3_USE_SSL=${{ inputs.sccache-s3-use-ssl }}" >> "$GITHUB_ENV"
          echo "SCCACHE_S3_KEY_PREFIX=$prefix" >> "$GITHUB_ENV"
          if [ -n '${{ inputs.sccache-endpoint }}' ]; then
            echo "SCCACHE_ENDPOINT=${{ inputs.sccache-endpoint }}" >> "$GITHUB_ENV"
          fi
          if [ '${{ inputs.sccache-s3-enable-virtual-host-style }}' = 'true' ]; then
            echo "SCCACHE_S3_ENABLE_VIRTUAL_HOST_STYLE=true" >> "$GITHUB_ENV"
          fi
        fi
        if [ '${{ inputs.sccache-wrap-cc }}' = 'true' ]; then
          echo "CC=sccache cc" >> "$GITHUB_ENV"
          echo "CXX=sccache c++" >> "$GITHUB_ENV"
        fi

    - name: Start sccache
      if: ${{ inputs.sccache == 'true' }}
      shell: bash
      run: |
        sccache --start-server
        sccache --show-stats