package admin

import (
	"reflect"
	"strconv"
	"strings"

	"github.com/go-playground/validator/v10"
	"github.com/gofiber/fiber/v2"

	distributionapp "github.com/break/junhong_cmp_fiber/internal/application/distributionwithdrawal"
	distributiondomain "github.com/break/junhong_cmp_fiber/internal/domain/distribution"
	"github.com/break/junhong_cmp_fiber/internal/model/dto"
	distributionquery "github.com/break/junhong_cmp_fiber/internal/query/distributionwithdrawal"
	"github.com/break/junhong_cmp_fiber/pkg/constants"
	"github.com/break/junhong_cmp_fiber/pkg/errors"
	"github.com/break/junhong_cmp_fiber/pkg/middleware"
	"github.com/break/junhong_cmp_fiber/pkg/response"
)

// WithdrawalQualificationHandler 提现资料资格后台 Handler。
type WithdrawalQualificationHandler struct {
	service   *distributionapp.QualificationService
	query     *distributionquery.Query
	validator *validator.Validate
}

// NewWithdrawalQualificationHandler 创建提现资料资格后台 Handler。
func NewWithdrawalQualificationHandler(
	service *distributionapp.QualificationService,
	query *distributionquery.Query,
	validate *validator.Validate,
) *WithdrawalQualificationHandler {
	return &WithdrawalQualificationHandler{service: service, query: query, validator: validate}
}

// SubmitWithdrawalQualification 提交或替换提现资料资格
// POST /api/admin/shops/:shop_id/withdrawal-qualifications
// 仅本人代理店铺；替换合同或法人身份证时同一事务新增版本并使旧有效版本失效。
func (h *WithdrawalQualificationHandler) SubmitWithdrawalQualification(c *fiber.Ctx) error {
	if h.service == nil {
		return errors.New(errors.CodeServiceUnavailable, "提现资料资格能力尚未配置")
	}
	var req dto.SubmitWithdrawalQualificationReq
	if err := c.BodyParser(&req); err != nil {
		return errors.New(errors.CodeInvalidParam, "请求参数解析失败")
	}
	shopID, err := strconv.ParseUint(c.Params("shop_id"), 10, 64)
	if err != nil || shopID == 0 {
		return errors.New(errors.CodeInvalidParam, "无效的店铺 ID")
	}
	// shop_id 只来自路径，必须在校验前回填，否则 ShopID 的 required 恒失败。
	req.ShopID = uint(shopID)
	if h.validator == nil {
		return errors.New(errors.CodeInternalError, "提现资料资格校验器未配置")
	}
	if err := h.validator.Struct(&req); err != nil {
		return errors.New(errors.CodeInvalidParam, validationMessage("提现资料资格参数不合法", &req, err))
	}
	result, err := h.service.Submit(c.UserContext(), uint(shopID), distributiondomain.QualificationInput{
		SubjectType:            req.SubjectType,
		SubjectCode:            req.SubjectCode,
		LegalPersonIDCard:      req.LegalPersonIDCard,
		ContractFileKey:        req.ContractFileKey,
		IDCardFrontFileKey:     req.IDCardFrontFileKey,
		IDCardBackFileKey:      req.IDCardBackFileKey,
		BusinessLicenseFileKey: req.BusinessLicenseFileKey,
		ShopFrontFileKey:       req.ShopFrontFileKey,
		InvoiceFileKey:         req.InvoiceFileKey,
		InvoiceTitle:           req.InvoiceTitle,
		InvoiceSubjectCode:     req.InvoiceSubjectCode,
	})
	if err != nil {
		return err
	}
	return response.Success(c, &dto.SubmitWithdrawalQualificationResp{
		ID:         result.QualificationID,
		Status:     result.Status,
		StatusName: constants.GetWithdrawalQualificationStatusName(result.Status),
	})
}

// VoidWithdrawalQualification 超级管理员作废有效提现资料资格
// POST /api/admin/withdrawal-qualifications/:id/void
func (h *WithdrawalQualificationHandler) VoidWithdrawalQualification(c *fiber.Ctx) error {
	if h.service == nil {
		return errors.New(errors.CodeServiceUnavailable, "提现资料资格能力尚未配置")
	}
	id, err := strconv.ParseUint(c.Params("id"), 10, 64)
	if err != nil || id == 0 {
		return errors.New(errors.CodeInvalidParam, "无效的资格 ID")
	}
	var req dto.VoidWithdrawalQualificationReq
	if err := c.BodyParser(&req); err != nil {
		return errors.New(errors.CodeInvalidParam, "请求参数解析失败")
	}
	if h.validator == nil {
		return errors.New(errors.CodeInternalError, "提现资料资格校验器未配置")
	}
	if err := h.validator.Struct(&req); err != nil {
		return errors.New(errors.CodeInvalidParam, validationMessage("作废提现资料资格参数不合法", &req, err))
	}
	if err := h.service.Void(c.UserContext(), uint(id), req.Reason); err != nil {
		return err
	}
	return response.Success(c, nil)
}

// validationMessage 把请求校验失败转换为可定位字段的中文提示。
// 只使用字段的 description 与校验规则，不拼接底层错误文本，也不回显字段值。
func validationMessage(prefix string, req any, err error) string {
	fieldErrs, ok := err.(validator.ValidationErrors)
	if !ok || len(fieldErrs) == 0 {
		return prefix
	}
	return prefix + "：" + describeFieldError(req, fieldErrs[0])
}

// describeFieldError 用字段中文名与失败规则描述单个字段错误。
func describeFieldError(req any, fieldErr validator.FieldError) string {
	label := fieldDescription(req, fieldErr.StructField())
	switch fieldErr.Tag() {
	case "required":
		// 数字字段的 required 只在零值失败；说“不能为空”会误导为缺字段。
		if isNumericField(req, fieldErr.StructField()) {
			return label + "必须大于 0"
		}
		return label + "不能为空"
	case "min":
		if isNumericField(req, fieldErr.StructField()) {
			return label + "不能小于 " + fieldErr.Param()
		}
		return label + "长度不能小于 " + fieldErr.Param()
	case "max":
		if isNumericField(req, fieldErr.StructField()) {
			return label + "不能超过 " + fieldErr.Param()
		}
		return label + "长度不能超过 " + fieldErr.Param()
	case "oneof":
		return label + "必须为 " + strings.ReplaceAll(fieldErr.Param(), " ", "/") + " 之一"
	default:
		return label + "不合法（" + fieldErr.Tag() + "）"
	}
}

// isNumericField 判断字段是否为整数或浮点类型。
func isNumericField(req any, fieldName string) bool {
	field, ok := lookupField(req, fieldName)
	if !ok {
		return false
	}
	switch field.Type.Kind() {
	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
		reflect.Float32, reflect.Float64:
		return true
	default:
		return false
	}
}

// lookupField 在去指针的结构体类型上按名取字段。
func lookupField(req any, fieldName string) (reflect.StructField, bool) {
	typ := reflect.TypeOf(req)
	for typ != nil && typ.Kind() == reflect.Ptr {
		typ = typ.Elem()
	}
	if typ == nil || typ.Kind() != reflect.Struct {
		return reflect.StructField{}, false
	}
	return typ.FieldByName(fieldName)
}

// fieldDescription 取字段 description 的首个中文短语作为提示名，缺失时退回字段名。
func fieldDescription(req any, fieldName string) string {
	field, ok := lookupField(req, fieldName)
	if !ok {
		return fieldName
	}
	description := strings.TrimSpace(field.Tag.Get("description"))
	if description == "" {
		return fieldName
	}
	if cut := strings.IndexAny(description, "（(：:，,；;"); cut > 0 {
		description = strings.TrimSpace(description[:cut])
	}
	if description == "" {
		return fieldName
	}
	// 提示名以拉丁字母/数字结尾时补一个空格，避免与后续中文粘连。
	if last := description[len(description)-1]; last < 0x80 {
		description += " "
	}
	return description
}

// ListWithdrawalQualifications 查询提现资料资格版本
// GET /api/admin/shops/:shop_id/withdrawal-qualifications
// 仅返回当前账号数据范围内的资料版本；证件号脱敏，附件只返回对象存储 Key。
func (h *WithdrawalQualificationHandler) ListWithdrawalQualifications(c *fiber.Ctx) error {
	if h.query == nil {
		return errors.New(errors.CodeInternalError, "提现资料资格查询能力未配置")
	}
	var req dto.WithdrawalQualificationListReq
	if err := c.QueryParser(&req); err != nil {
		return errors.New(errors.CodeInvalidParam, "请求参数解析失败")
	}
	// 路由路径必带 shop_id；数据范围由 CanManageShop 在业务边界强制。
	shopID, err := strconv.ParseUint(c.Params("shop_id"), 10, 64)
	if err != nil || shopID == 0 {
		return errors.New(errors.CodeInvalidParam, "无效的店铺 ID")
	}
	if err := middleware.CanManageShop(c.UserContext(), uint(shopID)); err != nil {
		return errors.New(errors.CodeForbidden, "无权限操作该资源或资源不存在")
	}
	result, err := h.query.ListQualifications(c.UserContext(), []uint{uint(shopID)}, &req)
	if err != nil {
		return err
	}
	return response.SuccessWithPagination(c, result.Items, result.Total, result.Page, result.Size)
}