package comb

import (
	"context"
	"encoding/json"
	"fmt"
	"sort"
	"sync"

	"tyapi-server/internal/domains/api/services/processors"
	"tyapi-server/internal/domains/product/entities"
	"tyapi-server/internal/domains/product/services"
)

// CombService 组合包服务
type CombService struct {
	productManagementService *services.ProductManagementService
	processorRegistry        map[string]processors.ProcessorFunc
}

// NewCombService 创建组合包服务
func NewCombService(productManagementService *services.ProductManagementService) *CombService {
	return &CombService{
		productManagementService: productManagementService,
		processorRegistry:        make(map[string]processors.ProcessorFunc),
	}
}

// RegisterProcessor 注册处理器
func (cs *CombService) RegisterProcessor(apiCode string, processor processors.ProcessorFunc) {
	cs.processorRegistry[apiCode] = processor
}

// ProcessCombRequest 处理组合包请求 - 实现 CombServiceInterface
func (cs *CombService) ProcessCombRequest(ctx context.Context, params []byte, deps *processors.ProcessorDependencies, packageCode string) (*processors.CombinedResult, error) {
	// 1. 根据组合包code获取产品信息
	packageProduct, err := cs.productManagementService.GetProductByCode(ctx, packageCode)
	if err != nil {
		return nil, fmt.Errorf("获取组合包信息失败: %s", err.Error())
	}

	if !packageProduct.IsPackage {
		return nil, fmt.Errorf("产品 %s 不是组合包", packageCode)
	}

	// 2. 获取组合包的所有子产品
	packageItems, err := cs.productManagementService.GetPackageItems(ctx, packageProduct.ID)
	if err != nil {
		return nil, fmt.Errorf("获取组合包子产品失败: %s", err.Error())
	}

	if len(packageItems) == 0 {
		return nil, fmt.Errorf("组合包 %s 没有配置子产品", packageCode)
	}

	// 3. 并发调用所有子产品的处理器
	results := cs.processSubProducts(ctx, params, deps, packageItems)

	// 4. 组合结果
	return cs.combineResults(results)
}

// processSubProducts 并发处理子产品
func (cs *CombService) processSubProducts(
	ctx context.Context,
	params []byte,
	deps *processors.ProcessorDependencies,
	packageItems []*entities.ProductPackageItem,
) []*processors.SubProductResult {
	results := make([]*processors.SubProductResult, 0, len(packageItems))
	var wg sync.WaitGroup
	var mu sync.Mutex

	// 并发处理每个子产品
	for _, item := range packageItems {
		wg.Add(1)
		go func(item *entities.ProductPackageItem) {
			defer wg.Done()

			result := cs.processSingleSubProduct(ctx, params, deps, item)

			mu.Lock()
			results = append(results, result)
			mu.Unlock()
		}(item)
	}

	wg.Wait()

	// 按SortOrder排序
	sort.Slice(results, func(i, j int) bool {
		return results[i].SortOrder < results[j].SortOrder
	})

	return results
}

// processSingleSubProduct 处理单个子产品
func (cs *CombService) processSingleSubProduct(
	ctx context.Context,
	params []byte,
	deps *processors.ProcessorDependencies,
	item *entities.ProductPackageItem,
) *processors.SubProductResult {
	result := &processors.SubProductResult{
		ApiCode:   item.Product.Code,
		SortOrder: item.SortOrder,
		Success:   false,
	}

	// 查找对应的处理器
	processor, exists := cs.processorRegistry[item.Product.Code]
	if !exists {
		result.Error = fmt.Sprintf("未找到处理器: %s", item.Product.Code)
		return result
	}

	// 调用处理器
	respBytes, err := processor(ctx, params, deps)
	if err != nil {
		result.Error = err.Error()
		return result
	}

	// 解析响应
	var responseData interface{}
	if err := json.Unmarshal(respBytes, &responseData); err != nil {
		result.Error = fmt.Sprintf("解析响应失败: %s", err.Error())
		return result
	}

	result.Success = true
	result.Data = responseData

	return result
}

// combineResults 组合所有子产品的结果
func (cs *CombService) combineResults(results []*processors.SubProductResult) (*processors.CombinedResult, error) {
	// 构建组合结果
	combinedResult := &processors.CombinedResult{
		Responses: results,
	}
	return combinedResult, nil
}