package logic

import (
	"context"
	"fmt"

	v1 "easygoadmin/api/v1"
	"easygoadmin/internal/dao"
	"easygoadmin/internal/service"
	"easygoadmin/utility/excel"
	"easygoadmin/utility/upload"
)

// ============================== 案例演示业务实现 ==============================

// sExample 案例演示业务实现
// 实现 service.IExample 接口，接口定义见 api/v1/example.go
type sExample struct{}

func init() {
	service.RegisterExample(&sExample{})
}

// exampleSerializeMaps 枚举字段到字典编码的映射
// {field}Text 由基座自动填充
var exampleSerializeMaps = map[string]string{
	"status": "example_status",
}

// exampleSpec 案例演示模块声明
//
// 采用声明式实现：查询、输出与规则均在声明中定义，方法仅做委托
var exampleSpec = ModuleSpec[v1.ExampleItem, v1.ExampleItem, v1.ExampleDetailRes]{
	Model:         dao.Example.Ctx,
	LikeFields:    []string{"name"},
	EqFields:      []string{"type", "status"},
	OrderBy:       "sort, id",
	SerializeMaps: exampleSerializeMaps,
	FileFields: []string{
		"avatar",
	},
	FileSaveDir: "example",
	ToData:      exampleToData,
}

// exampleToData 全量表单语义转换
// 新增与修改均提交全部字段，兼容两种入参类型
func exampleToData(req any) map[string]any {
	switch r := req.(type) {
	case *v1.ExampleAddReq:
		return map[string]any{
			"name":   r.Name,
			"avatar": r.Avatar,
			"type":   r.Type,
			"status": r.Status,
			"sort":   r.Sort,
		}
	case *v1.ExampleUpdateReq:
		return map[string]any{
			"name":   r.Name,
			"avatar": r.Avatar,
			"type":   r.Type,
			"status": r.Status,
			"sort":   r.Sort,
		}
	}
	panic(fmt.Sprintf("exampleToData: 不支持的入参类型 %T", req))
}

// ---------- 标准方法：委托基座 ----------

// Page 案例演示分页
// 按查询条件分页返回案例演示列表
func (s *sExample) Page(ctx context.Context, req *v1.ExamplePageReq) (res *v1.ExamplePageRes, err error) {
	list, total, err := exampleSpec.Page(ctx, req, req.GetPageNo(), req.GetPageSize())
	if err != nil {
		return nil, err
	}
	return v1.NewPageData(req.GetPageNo(), req.GetPageSize(), total, derefSlice(list)), nil
}

// List 案例演示平铺列表
// data 直接为数组，树形结构由前端 buildTree 构建
func (s *sExample) List(ctx context.Context, req *v1.ExampleListReq) (res v1.ExampleListRes, err error) {
	list, err := exampleSpec.List(ctx, req)
	if err != nil {
		return nil, err
	}
	return derefSlice(list), nil
}

// Detail 案例演示详情
// 按主键ID查询详情
func (s *sExample) Detail(ctx context.Context, req *v1.ExampleDetailReq) (res *v1.ExampleDetailRes, err error) {
	return exampleSpec.Detail(ctx, req.Id, req)
}

// Add 新增案例演示
// 新增成功后返回新记录ID
func (s *sExample) Add(ctx context.Context, req *v1.ExampleAddReq) (res *v1.ExampleIdRes, err error) {
	id, err := exampleSpec.Add(ctx, req)
	if err != nil {
		return nil, err
	}
	return &v1.ExampleIdRes{Id: id}, nil
}

// Update 修改案例演示
// 按主键ID更新记录
func (s *sExample) Update(ctx context.Context, req *v1.ExampleUpdateReq) (res *v1.ExampleUpdateRes, err error) {
	if err = exampleSpec.Update(ctx, req.Id, req); err != nil {
		return nil, err
	}
	return &v1.ExampleUpdateRes{}, nil
}

// Status 案例演示状态
// 非标准方法，保留手写实现，设置记录的状态字段
func (s *sExample) Status(ctx context.Context, req *v1.ExampleStatusReq) (res *v1.ExampleStatusRes, err error) {
	if _, err = dao.Example.Ctx(ctx).Where("id", req.Id).Data(map[string]any{"status": req.Status}).Update(); err != nil {
		return nil, err
	}
	return &v1.ExampleStatusRes{}, nil
}

// Delete 删除案例演示
// 按主键ID删除单条记录
func (s *sExample) Delete(ctx context.Context, req *v1.ExampleDeleteReq) (res *v1.ExampleDeleteRes, err error) {
	if err = exampleSpec.Delete(ctx, req.Id); err != nil {
		return nil, err
	}
	return &v1.ExampleDeleteRes{}, nil
}

// BatchDelete 批量删除案例演示
// 按主键ID列表批量删除记录
func (s *sExample) BatchDelete(ctx context.Context, req *v1.ExampleBatchDeleteReq) (res *v1.ExampleBatchDeleteRes, err error) {
	if err = exampleSpec.BatchDelete(ctx, req.Ids); err != nil {
		return nil, err
	}
	return &v1.ExampleBatchDeleteRes{}, nil
}

// Import 导入案例演示
// 表头为表单字段名，按列序写入
func (s *sExample) Import(ctx context.Context, req *v1.ExampleImportReq) (res *v1.ExampleImportRes, err error) {
	_, rows, err := excel.ReadSheet(req.File)
	if err != nil {
		return nil, err
	}
	res = &v1.ExampleImportRes{Total: len(rows)}
	for i, row := range rows {
		if cellAt(row, 0) == "" {
			res.Failed++
			res.Reasons = append(res.Reasons, fmt.Sprintf("第%d行：案例名称为空", i+2))
			continue
		}
		if _, e := dao.Example.Ctx(ctx).Data(map[string]any{
			"name":   cellAt(row, 0),
			"avatar": cellAt(row, 1),
			"type":   cellInt(row, 2, 0),
			"status": cellInt(row, 3, 0),
			"sort":   cellInt(row, 4, 0),
		}).Insert(); e != nil {
			res.Failed++
			res.Reasons = append(res.Reasons, fmt.Sprintf("第%d行：写入失败 %v", i+2, e))
			continue
		}
		res.Success++
	}
	return res, nil
}

// Export 导出案例演示
// 与列表同套筛选条件，枚举列输出字典文本
func (s *sExample) Export(ctx context.Context, req *v1.ExampleExportReq) (res *v1.ExampleExportRes, err error) {
	rows, err := exampleSpec.applyFilters(ctx, exampleSpec.Model(ctx), req).Order("sort, id").All()
	if err != nil {
		return nil, err
	}
	headers := []string{"案例名称", "案例图片", "案例类型", "案例状态", "案例排序"}
	data := make([][]any, 0, len(rows))
	for _, r := range rows {
		data = append(data, []any{r["name"].String(), r["avatar"].String(), DictGetText(ctx, "example_type", r["type"]), DictGetText(ctx, "example_status", r["status"]), r["sort"].String()})
	}
	fileName, _, err := excel.WriteSheet(upload.BaseDir(ctx), "案例演示数据", headers, data)
	if err != nil {
		return nil, err
	}
	url := upload.GetFileUrl(ctx, fileName)
	return &url, nil
}