// 功能描述：用户地址新增、编辑、归档及默认切换，账户行锁保护并发写入。
// 版本：1.0.0。
package user

import (
	"errors"
	"math"
	"strconv"
	"strings"

	"git.apinb.com/bsm-sdk/core/errcode"
	"git.apinb.com/bsm-sdk/core/infra"
	"git.apinb.com/heqiapp/platforms/backend/api/internal/impl"
	common "git.apinb.com/heqiapp/platforms/backend/api/internal/logic/common"
	"git.apinb.com/heqiapp/platforms/backend/api/internal/models"
	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
	"gorm.io/gorm/clause"
)

// addressRequest 保留旧新增字段，联系人省略时从本账户补齐。
type addressRequest struct {
	Address      string  `json:"address" binding:"required,max=255"`
	ContactName  *string `json:"contact_name" binding:"omitempty,max=64"`
	ContactPhone *string `json:"contact_phone" binding:"omitempty,max=32"`
	Longitude    string  `json:"longitude" binding:"max=32"`
	Latitude     string  `json:"latitude" binding:"max=32"`
	IsDefault    bool    `json:"is_default"`
	RequestNo    string  `json:"request_no" binding:"max=64"`
}

// validAddressCoordinates 接受手动地址的空坐标；有坐标时必须成对且为合法经纬度。
func validAddressCoordinates(longitude, latitude string) bool {
	if longitude == "" && latitude == "" {
		return true
	}
	lon, e1 := strconv.ParseFloat(longitude, 64)
	lat, e2 := strconv.ParseFloat(latitude, 64)
	return e1 == nil && e2 == nil && !math.IsNaN(lon) && !math.IsNaN(lat) && lon >= -180 && lon <= 180 && lat >= -90 && lat <= 90
}

// lockAddressOwner 按账户串行处理默认地址和幂等请求，避免首次新增的并发竞态。
func lockAddressOwner(tx *gorm.DB, id uint64) error {
	return tx.Clauses(clause.Locking{Strength: "UPDATE"}).Select("id").First(&models.UserAccount{}, id).Error
}

// clearAddressDefault 在同一事务取消旧默认，保留现有唯一索引约束。
func clearAddressDefault(tx *gorm.DB, userID uint64) error {
	return tx.Model(&models.UserAddress{}).Where("user_account_id = ? AND is_default = ?", userID, true).Update("is_default", false).Error
}

// SaveAddress 新增地址，带 request_no 的重试返回原标识，不重复创建。
func SaveAddress(ctx *gin.Context) { writeAddress(ctx, false) }

// UpdateAddress 仅更新本人地址，旧订单使用已有快照，不随地址修改。
func UpdateAddress(ctx *gin.Context) { writeAddress(ctx, true) }

// writeAddress 校验请求后在事务中持久化，失败时保持原地址和默认设置。
func writeAddress(ctx *gin.Context, updating bool) {
	account, ok := common.UserAccount(ctx)
	if !ok {
		return
	}
	var request addressRequest
	if ctx.ShouldBindJSON(&request) != nil {
		infra.Response.Error(ctx, errcode.ErrInvalidArgument)
		return
	}
	request.Address = strings.TrimSpace(request.Address)
	request.Longitude = strings.TrimSpace(request.Longitude)
	request.Latitude = strings.TrimSpace(request.Latitude)
	if request.Address == "" || !validAddressCoordinates(request.Longitude, request.Latitude) {
		infra.Response.Error(ctx, errcode.ErrInvalidArgument)
		return
	}
	var address models.UserAddress
	err := impl.DBService.Transaction(func(tx *gorm.DB) error {
		if err := lockAddressOwner(tx, account.ID); err != nil {
			return err
		}
		if updating {
			if err := tx.Where("identity = ? AND user_account_id = ? AND status <> ?", ctx.Param("identity"), account.ID, common.StatusArchived).First(&address).Error; err != nil {
				return errcode.ErrRecordNotFound
			}
		} else {
			address = models.UserAddress{Entity: common.NewEntity(common.StatusEnable), UserAccountID: account.ID, RequestNo: request.RequestNo}
		}
		name, phone := address.ContactName, address.ContactPhone
		if name == "" {
			name = account.Name
		}
		if phone == "" {
			phone = account.Phone
		}
		if request.ContactName != nil {
			name = strings.TrimSpace(*request.ContactName)
		}
		if request.ContactPhone != nil {
			phone = strings.TrimSpace(*request.ContactPhone)
		}
		if (request.ContactName != nil && name == "") || !common.ValidPhone(phone) {
			return errcode.ErrInvalidArgument
		}
		if !updating && request.RequestNo != "" {
			var previous models.UserAddress
			err := tx.Where("user_account_id = ? AND request_no = ?", account.ID, request.RequestNo).First(&previous).Error
			if err == nil {
				if previous.Status == common.StatusArchived || previous.Address != request.Address || previous.ContactName != name || previous.ContactPhone != phone || previous.Longitude != request.Longitude || previous.Latitude != request.Latitude {
					return errcode.ErrInvalidArgument
				}
				address = previous
				return nil
			}
			if !errors.Is(err, gorm.ErrRecordNotFound) {
				return err
			}
		}
		if request.IsDefault {
			if err := clearAddressDefault(tx, account.ID); err != nil {
				return err
			}
		}
		address.Address, address.ContactName, address.ContactPhone = request.Address, name, phone
		address.Longitude, address.Latitude, address.IsDefault = request.Longitude, request.Latitude, request.IsDefault
		if updating {
			return tx.Model(&address).Select("address", "contact_name", "contact_phone", "longitude", "latitude", "is_default").Updates(&address).Error
		}
		return tx.Create(&address).Error
	})
	if err != nil {
		infra.Response.Error(ctx, err)
		return
	}
	infra.Response.Success(ctx, gin.H{"identity": address.Identity})
}

// SetDefaultAddress 设置本人有效地址为默认，不接受请求体中的用户或地址归属。
func SetDefaultAddress(ctx *gin.Context) { changeAddressState(ctx, false) }

// DeleteAddress 归档本人地址并取消默认；重复删除成功，历史订单引用保留。
func DeleteAddress(ctx *gin.Context) { changeAddressState(ctx, true) }

// changeAddressState 所有权校验先于默认切换，跨账户请求不能影响本人的默认设置。
func changeAddressState(ctx *gin.Context, deleting bool) {
	account, ok := common.UserAccount(ctx)
	if !ok {
		return
	}
	err := impl.DBService.Transaction(func(tx *gorm.DB) error {
		if err := lockAddressOwner(tx, account.ID); err != nil {
			return err
		}
		var address models.UserAddress
		if err := tx.Where("identity = ? AND user_account_id = ?", ctx.Param("identity"), account.ID).First(&address).Error; err != nil {
			return errcode.ErrRecordNotFound
		}
		if deleting {
			return tx.Model(&address).Updates(map[string]any{"status": common.StatusArchived, "is_default": false}).Error
		}
		if address.Status == common.StatusArchived {
			return errcode.ErrRecordNotFound
		}
		if err := clearAddressDefault(tx, account.ID); err != nil {
			return err
		}
		return tx.Model(&address).Update("is_default", true).Error
	})
	if err != nil {
		infra.Response.Error(ctx, err)
		return
	}
	infra.Response.Success(ctx, gin.H{"identity": ctx.Param("identity")})
}