package balance

import (
	"context"
	"database/sql"
	"errors"
	"fmt"
	"math"
	"strings"

	"github.com/gogf/gf/v2/database/gdb"
	"github.com/gogf/gf/v2/errors/gerror"
	"github.com/gogf/gf/v2/frame/g"
	"github.com/gogf/gf/v2/os/gtime"
	"github.com/gogf/gf/v2/util/gconv"
)

const (
	rechargeStatusPending = iota
	rechargeStatusPaid
	rechargeStatusExpired

	rechargeChannelAlipay = 1
)

type TradeQueryResult struct {
	OutTradeNo   string
	TradeNo      string
	TradeStatus  string
	TotalAmount  string
	BuyerLogonID string
}

type TradeQueryer interface {
	Query(context.Context, string) (*TradeQueryResult, error)
}

type Service struct {
	queryer TradeQueryer
}

func New() *Service {
	return NewWithQuery(newAlipayTradeQueryer())
}

func NewWithQuery(queryer TradeQueryer) *Service {
	return &Service{queryer: queryer}
}

func (s *Service) CheckRechargeTimeout(ctx context.Context, outTradeNo string) error {
	outTradeNo = strings.TrimSpace(outTradeNo)
	if outTradeNo == "" {
		return nil
	}

	detail := rechargeDetail{}
	if err := g.DB().Model("t_balance_detail").Ctx(ctx).
		Where("order_sn", outTradeNo).
		Where("transaction_channel", rechargeChannelAlipay).
		Scan(&detail); err != nil {
		if errors.Is(err, sql.ErrNoRows) {
			return nil
		}
		return gerror.Wrap(err, "query recharge detail failed")
	}
	if detail.ID == 0 || detail.TransactionStatus != rechargeStatusPending {
		return nil
	}
	if s.queryer == nil {
		return gerror.New("alipay trade queryer is not configured")
	}

	result, err := s.queryer.Query(ctx, outTradeNo)
	if err != nil {
		return err
	}
	if result != nil && (result.TradeStatus == "TRADE_SUCCESS" || result.TradeStatus == "TRADE_FINISHED") {
		return s.creditRecharge(ctx, detail, result)
	}

	_, err = g.DB().Model("t_balance_detail").Ctx(ctx).
		Where("id", detail.ID).
		Where("transaction_status", rechargeStatusPending).
		Data(g.Map{
			"transaction_status": rechargeStatusExpired,
			"remark":             "Alipay recharge timed out without payment",
			"updated_at":         gtime.Now(),
		}).
		Update()
	return gerror.Wrap(err, "expire recharge detail failed")
}

func (s *Service) creditRecharge(ctx context.Context, initial rechargeDetail, result *TradeQueryResult) error {
	amount := gconv.Float64(strings.TrimSpace(result.TotalAmount))
	if amount <= 0 {
		return gerror.New("paid recharge has invalid amount")
	}

	return g.DB().Transaction(ctx, func(ctx context.Context, tx gdb.TX) error {
		detail := rechargeDetail{}
		detailModel := lockForUpdate(tx.Ctx(ctx).Model("t_balance_detail"))
		if err := detailModel.
			Where("id", initial.ID).
			Scan(&detail); err != nil {
			return gerror.Wrap(err, "lock recharge detail failed")
		}
		if detail.ID == 0 || detail.TransactionStatus == rechargeStatusPaid {
			return nil
		}
		if detail.TransactionStatus != rechargeStatusPending {
			return gerror.New("recharge order is closed")
		}
		if math.Abs(detail.Amount-amount) > 0.001 {
			return gerror.New("paid amount does not match recharge detail")
		}

		account := agentBalance{}
		accountModel := lockForUpdate(tx.Ctx(ctx).Model("t_agent_balance"))
		if err := accountModel.
			Where("dept_id", detail.DeptID).
			Where("tenant_id", detail.TenantID).
			Scan(&account); err != nil {
			return gerror.Wrap(err, "lock agent balance failed")
		}
		now := gtime.Now()
		if account.ID == 0 {
			id, err := tx.Ctx(ctx).Model("t_agent_balance").Data(g.Map{
				"dept_id":                detail.DeptID,
				"balance":                0,
				"withdraw_amount":        0,
				"withdraw_amount_status": 1,
				"invoice_amount":         0,
				"can_invoice_amount":     0,
				"credit_limit":           0,
				"used_credit":            0,
				"pending_repayment":      0,
				"status":                 0,
				"tenant_id":              detail.TenantID,
				"created_dept":           detail.CreatedDept,
				"created_by":             detail.CreatedBy,
				"created_at":             now,
			}).InsertAndGetId()
			if err != nil {
				return gerror.Wrap(err, "initialize agent balance failed")
			}
			account = agentBalance{ID: id}
		}

		before := account.Balance
		after := before + detail.Amount
		if _, err := tx.Ctx(ctx).Model("t_agent_balance").Where("id", account.ID).Data(g.Map{
			"balance":    after,
			"updated_by": detail.CreatedBy,
			"updated_at": now,
		}).Update(); err != nil {
			return gerror.Wrap(err, "update agent balance failed")
		}
		_, err := tx.Ctx(ctx).Model("t_balance_detail").Where("id", detail.ID).Data(g.Map{
			"transaction_status": rechargeStatusPaid,
			"transaction_time":   now,
			"before_balance":     before,
			"balance_after":      after,
			"channel_serial_no":  result.TradeNo,
			"remark":             fmt.Sprintf("Alipay recharge, buyer: %s", result.BuyerLogonID),
			"updated_by":         detail.CreatedBy,
			"updated_at":         now,
		}).Update()
		return gerror.Wrap(err, "mark recharge paid failed")
	})
}

type rechargeDetail struct {
	ID                int64   `orm:"id"`
	DeptID            int64   `orm:"dept_id"`
	TransactionStatus int     `orm:"transaction_status"`
	Amount            float64 `orm:"amount"`
	TenantID          string  `orm:"tenant_id"`
	CreatedDept       int64   `orm:"created_dept"`
	CreatedBy         int64   `orm:"created_by"`
}

type agentBalance struct {
	ID      int64   `orm:"id"`
	Balance float64 `orm:"balance"`
}

func lockForUpdate(model *gdb.Model) *gdb.Model {
	if g.DB().GetConfig().Type == "sqlite" {
		return model
	}
	return model.LockUpdate()
}