name: 'Reusable Docker Image Build'
description: '通用的 Docker 镜像构建 / 验证 / 清理逻辑，用于在各仓库中复用'

inputs:
  dockerfile:
    description: 'Dockerfile 路径（相对于仓库根目录）'
    required: true
  context:
    description: '构建上下文路径（相对于仓库根目录）'
    required: false
    default: '.'
  image_name:
    description: 'Docker 镜像名称（不含标签）'
    required: true
  image_tag:
    description: 'Docker 镜像标签/版本'
    required: true
  enable_cache:
    description: '是否启用 Docker 构建缓存'
    required: false
    default: 'true'
  build_args:
    description: 'Docker 构建参数（每行一个，格式: KEY=VALUE）'
    required: false
    default: ''

runs:
  using: 'composite'
  steps:
    - name: Prepare build arguments
      id: prepare
      shell: bash
      run: |
        echo "====== 准备构建参数 ======"

        DOCKERFILE="${{ inputs.dockerfile }}"
        CONTEXT="${{ inputs.context }}"
        IMAGE_NAME="${{ inputs.image_name }}"
        IMAGE_TAG="${{ inputs.image_tag }}"
        FULL_IMAGE="${IMAGE_NAME}:${IMAGE_TAG}"

        echo "Dockerfile: $DOCKERFILE"
        echo "Context: $CONTEXT"
        echo "Image: $FULL_IMAGE"

        # 验证 Dockerfile 是否存在
        if [ ! -f "$DOCKERFILE" ]; then
          echo "✗ Dockerfile 不存在: $DOCKERFILE"
          exit 1
        fi

        # 验证构建上下文目录是否存在
        if [ ! -d "$CONTEXT" ]; then
          echo "✗ 构建上下文目录不存在: $CONTEXT"
          exit 1
        fi

        echo "✓ 构建参数验证通过"
        echo ""

        # 设置输出变量
        echo "full_image=$FULL_IMAGE" >> "$GITHUB_OUTPUT"

        # 处理构建参数
        BUILD_ARGS=""
        if [ -n "${{ inputs.build_args }}" ]; then
          echo "====== 构建参数 ======"
          while IFS= read -r line; do
            if [ -n "$line" ]; then
              echo "  $line"
              BUILD_ARGS="$BUILD_ARGS --build-arg $line"
            fi
          done <<< "${{ inputs.build_args }}"
          echo ""
        fi

        echo "build_args=$BUILD_ARGS" >> "$GITHUB_OUTPUT"

    - name: Build Docker image
      shell: bash
      run: |
        echo "====== 开始构建 Docker 镜像 ======"
        echo "构建时间: $(date '+%Y-%m-%d %H:%M:%S')"
        echo "分支: ${{ github.ref_name }}"
        echo ""

        echo "====== 构建配置 ======"
        echo "镜像: ${{ steps.prepare.outputs.full_image }}"
        echo "Dockerfile: ${{ inputs.dockerfile }}"
        echo "Context: ${{ inputs.context }}"
        echo ""

        # 构建命令
        BUILD_CMD="docker build \
          -t ${{ steps.prepare.outputs.full_image }} \
          -f ${{ inputs.dockerfile }} \
          ${{ steps.prepare.outputs.build_args }} \
          ${{ inputs.context }}"

        echo "执行命令:"
        echo "$BUILD_CMD"
        echo ""

        # 执行构建
        eval $BUILD_CMD

        echo ""
        echo "====== 镜像构建完成 ======"

    - name: Verify image
      shell: bash
      run: |
        echo "====== 验证构建的镜像 ======"

        IMAGE="${{ steps.prepare.outputs.full_image }}"

        if docker image inspect "${IMAGE}" >/dev/null 2>&1; then
          SIZE=$(docker image inspect "${IMAGE}" --format='{{.Size}}' | awk '{printf "%.2f", $1/1024/1024}')
          CREATED=$(docker image inspect "${IMAGE}" --format='{{.Created}}')
          ID=$(docker image inspect "${IMAGE}" --format='{{.Id}}' | cut -d':' -f2 | cut -c1-12)

          echo "✓ ${IMAGE}"
          echo "  镜像 ID: ${ID}"
          echo "  大小: ${SIZE} MB"
          echo "  创建时间: ${CREATED}"
        else
          echo "✗ ${IMAGE} 验证失败"
          exit 1
        fi

        echo ""
        echo "✓ 镜像验证成功"

    - name: Cleanup
      if: always()
      shell: bash
      run: |
        echo "====== 清理悬空镜像 ======"
        docker image prune -f
        echo "✓ 清理完成"