action.yml

name: 'Palantir Java Format Check'
description: 'Checks Java code formatting using palantir-java-formatter native binary'
author: 'abashev'

branding:
  icon: 'check-circle'
  color: 'green'

inputs:
  version:
    description: 'Version of palantir-java-formatter to use'
    required: true
    default: '2.89.0'
  mode:
    description: 'Which files to check: "changed" for files from PR/push, "all" for every .java file'
    required: false
    default: 'changed'

runs:
  using: 'composite'
  steps:
    - name: Detect platform
      id: platform
      shell: bash
      run: |
        OS=$(uname -s)
        ARCH=$(uname -m)

        case "${OS}-${ARCH}" in
          Linux-x86_64)  SUFFIX="linux-glibc_x86-64" ;;
          Linux-aarch64) SUFFIX="linux-glibc_aarch64" ;;
          Darwin-arm64)  SUFFIX="macos_aarch64" ;;
          *)
            echo "::error::No palantir-java-format native binary for ${OS}-${ARCH}. Supported: Linux x86_64, Linux aarch64, macOS aarch64."
            exit 1
            ;;
        esac

        echo "suffix=$SUFFIX" >> "$GITHUB_OUTPUT"

    - name: Cache palantir-java-format binary
      id: cache
      uses: actions/cache@v5
      with:
        path: ${{ github.action_path }}/palantir-java-format
        key: palantir-java-format-${{ inputs.version }}-${{ steps.platform.outputs.suffix }}

    - name: Download palantir-java-format native binary
      if: steps.cache.outputs.cache-hit != 'true'
      shell: bash
      run: |
        VERSION="${{ inputs.version }}"
        SUFFIX="${{ steps.platform.outputs.suffix }}"
        BASE_URL="https://repo1.maven.org/maven2/com/palantir/javaformat/palantir-java-format-native/${VERSION}"
        ARTIFACT="palantir-java-format-native-${VERSION}-nativeImage-${SUFFIX}.bin"
        DOWNLOAD_URL="${BASE_URL}/${ARTIFACT}"
        BINARY="${{ github.action_path }}/palantir-java-format"

        echo "Downloading palantir-java-format ${VERSION} (${SUFFIX})..."
        if ! curl -sSfL -o "$BINARY" "$DOWNLOAD_URL"; then
          rm -f "$BINARY"
          echo "::error::Failed to download palantir-java-format from: $DOWNLOAD_URL"
          exit 1
        fi

        chmod +x "$BINARY"

    - name: Set binary path
      shell: bash
      run: echo "PJF_BINARY=${{ github.action_path }}/palantir-java-format" >> "$GITHUB_ENV"

    - name: Collect files to check
      shell: bash
      run: |
        MODE="${{ inputs.mode }}"

        if [ "$MODE" = "all" ]; then
          echo "Mode: all — checking every .java file"
          FILES=$(find . -name '*.java' -not -path './.git/*' | tr '\n' ' ')
        elif [ -n "${{ github.event.pull_request.number }}" ]; then
          echo "Mode: changed (PR #${{ github.event.pull_request.number }})"
          FILES=$(gh pr diff ${{ github.event.pull_request.number }} --name-only | grep '\.java$' | tr '\n' ' ')
        elif [ -n "${{ github.event.before }}" ]; then
          echo "Mode: changed (push ${{ github.event.before }}...${{ github.sha }})"
          FILES=$(git diff --name-only --diff-filter=ACMR ${{ github.event.before }}...${{ github.sha }} -- '*.java' | tr '\n' ' ')
        else
          echo "Mode: changed — unknown event, falling back to all .java files"
          FILES=$(find . -name '*.java' -not -path './.git/*' | tr '\n' ' ')
        fi

        if [ -z "$FILES" ]; then
          echo "No Java files to check."
          echo "PJF_FILES=" >> "$GITHUB_ENV"
        else
          echo "Files to check:"
          echo "$FILES" | tr ' ' '\n' | grep -v '^$'
          echo "PJF_FILES=$FILES" >> "$GITHUB_ENV"
        fi
      env:
        GH_TOKEN: ${{ github.token }}

    - name: Run format check
      shell: bash
      run: |
        if [ -z "$PJF_FILES" ]; then
          echo "Nothing to check, skipping."
          exit 0
        fi

        UNFORMATTED=()
        for FILE in $PJF_FILES; do
          if [ -f "$FILE" ]; then
            if ! "$PJF_BINARY" --palantir --dry-run --set-exit-if-changed "$FILE" > /dev/null 2>&1; then
              UNFORMATTED+=("$FILE")
            fi
          fi
        done

        if [ ${#UNFORMATTED[@]} -gt 0 ]; then
          echo "::error::Java formatting issues found!"
          echo ""
          echo "The following files are not formatted correctly:"
          for FILE in "${UNFORMATTED[@]}"; do
            echo "  $FILE"
          done
          echo ""
          echo "Run palantir-java-formatter locally to fix:"
          echo "  palantir-java-format --palantir --replace ${UNFORMATTED[*]}"
          exit 1
        fi

        echo "All files are correctly formatted."