#!/bin/bash
# 通用Docker镜像构建+推送脚本
# 缓存策略（2026-08 起）：
#   - buildx 使用宿主机持久 builder (ci-builder-persist)，层缓存保存在
#     buildkit 容器/命名卷中，跨 job 共享、job 结束不清理
#   - registry cache 仅作为冷启动兜底读取
#   - 额外 tag（如分支 tag :develop）通过 EXTRA_TAGS 环境变量传入，随构建一并推送
# 用法: docker_build_push.sh [--no-cache] <Dockerfile> <image_tag> <cache_ref> [build_arg...]
# 环境变量:
#   EXTRA_TAGS  空格分隔的额外 tag（完整 image:tag 引用），可选
set -eu

# 单次 build 超时时间（秒），防止 docker buildx build 无限挂起
BUILD_TIMEOUT=1500
# 持久 builder 名（宿主机级，所有 CI job 共享；由 ensure_persistent_builder.sh 维护）
BUILDER_NAME="ci-builder-persist"

NO_CACHE_FLAG=""
if [ "$1" = "--no-cache" ]; then
  NO_CACHE_FLAG="--no-cache"
  shift
  echo "模式: --no-cache (不使用缓存，全新构建)"
fi

DOCKERFILE="$1"
IMAGE_TAG="$2"
CACHE_REF="$3"
shift 3
BUILD_ARGS=""
for arg in "$@"; do
  BUILD_ARGS="$BUILD_ARGS --build-arg $arg"
done

# Web 镜像 cache bust：计算 apps/web/ 的 git tree hash
# 当源码变化时 hash 变化，buildx 的 ARG 缓存键失效 → vite build 必定重新执行
if [ "${DOCKERFILE##*/}" = "web.Dockerfile" ]; then
  SOURCE_HASH=$(git rev-parse HEAD:apps/web 2>/dev/null || echo "")
  if [ -n "$SOURCE_HASH" ]; then
    echo "Web cache bust: SOURCE_HASH=${SOURCE_HASH}"
    BUILD_ARGS="$BUILD_ARGS --build-arg SOURCE_HASH=${SOURCE_HASH}"
  else
    echo "⚠️  无法计算 apps/web tree hash，跳过 cache bust"
  fi
fi

# 确保持久 builder 存在并使用（幂等）
if ! docker buildx inspect "$BUILDER_NAME" > /dev/null 2>&1; then
  echo "持久 builder 不存在，创建中..."
  docker buildx create --name "$BUILDER_NAME" --driver docker-container \
    --driver-opt network=host \
    --buildkitd-flags "--allow-insecure-entitlement network.host" \
    --platform linux/amd64
fi
docker buildx use "$BUILDER_NAME"
docker buildx inspect "$BUILDER_NAME" --bootstrap

# 组装额外 tag 参数
EXTRA_TAG_FLAGS=""
EXTRA_TAG_LIST=""
if [ -n "${EXTRA_TAGS:-}" ]; then
  for t in $EXTRA_TAGS; do
    EXTRA_TAG_FLAGS="$EXTRA_TAG_FLAGS -t $t"
    EXTRA_TAG_LIST="$EXTRA_TAG_LIST $t"
  done
fi

build_with_cache_retry() {
  local attempt=1
  local max_attempts=2
  while [ $attempt -le $max_attempts ]; do
    local build_output
    local exit_code
    set +e
    build_output=$(timeout ${BUILD_TIMEOUT} docker buildx build \
      $NO_CACHE_FLAG \
      $BUILD_ARGS \
      --cache-from "type=registry,ref=${CACHE_REF}" \
      -f "${DOCKERFILE}" \
      -t "${IMAGE_TAG}" \
      $EXTRA_TAG_FLAGS \
      --push \
      . 2>&1)
    exit_code=$?
    set -e
    if [ $exit_code -eq 0 ]; then
      echo "$build_output"
      return 0
    fi
    # 超时退出（exit code 124）
    if [ $exit_code -eq 124 ]; then
      echo "❌ Docker build TIMEOUT after ${BUILD_TIMEOUT}s - build hung and was killed"
      echo "$build_output" | tail -20
      return $exit_code
    fi
    # 检测到缓存/快照损坏类错误，重建 builder 后重试
    if echo "$build_output" | grep -qE "parent snapshot.*not found|snapshot.*does not exist|cache.*corrupt|failed to compute cache key|no such file or directory.*cache"; then
      echo "$build_output"
      echo ""
      echo "⚠️  builder 缓存异常，重建持久 builder 后重试 (attempt $attempt/$max_attempts)..."
      # 共享 builder 的重建必须串行：ci-builder-persist 被所有 build job 共用，
      # 若 job A 正在构建、job B 检测到损坏直接 rm，会把 A 正在用的 buildkit 杀掉。
      # 用 flock 串行化重建；拿到锁后再次检查 builder 健康度，已被别的 job 重建则直接复用。
      LOCK_FILE="/tmp/ci-builder-persist-rebuild.lock"
      exec 9>"$LOCK_FILE"
      echo "🔒 等待重建锁（最多 120s）..."
      if flock -w 120 9; then
        if docker buildx inspect "$BUILDER_NAME" --bootstrap >/dev/null 2>&1; then
          echo "✅ builder 已被其他并发 job 重建/恢复，直接复用"
        else
          echo "🔨 锁内重建持久 builder..."
          docker buildx rm "$BUILDER_NAME" >/dev/null 2>&1 || true
          docker buildx create --name "$BUILDER_NAME" --driver docker-container \
            --driver-opt network=host \
            --buildkitd-flags "--allow-insecure-entitlement network.host" \
            --platform linux/amd64
          docker buildx use "$BUILDER_NAME"
          docker buildx inspect "$BUILDER_NAME" --bootstrap
        fi
      else
        echo "⚠️ 等待重建锁超时，直接重试 build（失败将重试/--no-cache）"
        docker buildx use "$BUILDER_NAME" 2>/dev/null || true
      fi
      attempt=$((attempt + 1))
    else
      echo "$build_output"
      return $exit_code
    fi
  done
  return 1
}

echo "=== Build & push image (persistent builder cache) ==="
echo "Builder:      ${BUILDER_NAME} (persistent)"
echo "Registry cache(from): ${CACHE_REF}"
echo "Image tag:    ${IMAGE_TAG}"
[ -n "$EXTRA_TAG_LIST" ] && echo "Extra tags:   ${EXTRA_TAG_LIST}"
echo "Timeout:      ${BUILD_TIMEOUT}s"
echo ""

build_with_cache_retry

echo ""
echo "Image pushed: ${IMAGE_TAG}"
[ -n "$EXTRA_TAG_LIST" ] && echo "Also pushed:   ${EXTRA_TAG_LIST}"
echo ""
echo "Build completed: ${IMAGE_TAG}"