package repository

import (
	"code.30cm.net/digimon/app-cloudep-wallet-service/pkg/domain/entity"
	"code.30cm.net/digimon/app-cloudep-wallet-service/pkg/domain/repository"
	"code.30cm.net/digimon/app-cloudep-wallet-service/pkg/domain/wallet"
	"context"
	"database/sql"
	"fmt"
	"github.com/shopspring/decimal"
	"gorm.io/gorm"
	"gorm.io/gorm/clause"
	"time"
)

// 用戶某個幣種餘額
type userWallet struct {
	db    *gorm.DB
	uid   string
	asset string
	// local wallet相關計算的餘額存在這裡
	localWalletBalance map[wallet.Types]entity.Wallet
	// local order wallet相關計算的餘額存在這裡
	localOrderBalance map[int64]decimal.Decimal
	// local wallet內所有餘額變化紀錄
	transactions []entity.WalletTransaction
}

func NewUserWallet(db *gorm.DB, uid, asset string) repository.UserWalletService {
	return &userWallet{
		db:                 db,
		uid:                uid,
		asset:              asset,
		localWalletBalance: make(map[wallet.Types]entity.Wallet, len(wallet.AllTypes)),
		localOrderBalance:  make(map[int64]decimal.Decimal, len(wallet.AllTypes)),
	}
}

func (repo *userWallet) Create(ctx context.Context, uid, asset, brand string) ([]entity.Wallet, error) {
	wallets := make([]entity.Wallet, 0, len(wallet.AllTypes))
	for _, t := range wallet.AllTypes {
		var balance decimal.Decimal

		// 合約模擬初始資金
		if t == wallet.TypeSimulationAvailable {
			balance = wallet.InitContractSimulationAvailable
		}

		wallets = append(wallets, entity.Wallet{
			Brand:   brand,
			UID:     uid,
			Asset:   asset,
			Balance: balance,
			Type:    t,
		})
	}

	if err := repo.db.WithContext(ctx).Create(&wallets).Error; err != nil {
		return nil, err
	}

	for _, v := range wallets {
		repo.localWalletBalance[v.Type] = v
	}

	return wallets, nil
}

func (repo *userWallet) AllBalances(ctx context.Context) ([]entity.Wallet, error) {
	var result []entity.Wallet

	err := repo.walletUserWhere(repo.uid, repo.asset).
		WithContext(ctx).
		Select("id, crypto, balance, type").
		Find(&result).Error

	if err != nil {
		return []entity.Wallet{}, err
	}

	for _, v := range result {
		repo.localWalletBalance[v.Type] = v
	}

	return result, nil
}

func (repo *userWallet) Balance(ctx context.Context, kind wallet.Types) (entity.Wallet, error) {
	var result entity.Wallet

	err := repo.walletUserWhere(repo.uid, repo.asset).
		WithContext(ctx).
		Model(&result).
		Select("id, crypto, balance, type").
		Where("type = ?", kind).
		Take(&result).Error

	if err != nil {
		return entity.Wallet{}, repository.WrapNotFoundError(err)
	}

	repo.localWalletBalance[result.Type] = result

	return result, nil
}

func (repo *userWallet) Balances(ctx context.Context, kind []wallet.Types) ([]entity.Wallet, error) {
	var wallets []entity.Wallet

	err := repo.walletUserWhere(repo.uid, repo.asset).
		WithContext(ctx).
		Model(&entity.Wallet{}).
		Select("id, crypto, balance, type").
		Where("type IN ?", kind).
		Find(&wallets).Error

	if err != nil {
		return []entity.Wallet{}, repository.WrapNotFoundError(err)
	}

	for _, w := range wallets {
		repo.localWalletBalance[w.Type] = w
	}

	return wallets, nil
}

func (repo *userWallet) LocalBalance(kind wallet.Types) decimal.Decimal {
	w, ok := repo.localWalletBalance[kind]
	if !ok {
		return decimal.Zero
	}

	return w.Balance
}

func (repo *userWallet) BalanceXLock(ctx context.Context, kind wallet.Types) (entity.Wallet, error) {
	var result entity.Wallet

	err := repo.walletUserWhere(repo.uid, repo.asset).
		WithContext(ctx).
		Model(&result).
		Select("id, crypto, balance, type").
		Where("type = ?", kind).
		Clauses(clause.Locking{Strength: "UPDATE"}).
		Take(&result).Error

	if err != nil {
		return entity.Wallet{}, repository.WrapNotFoundError(err)
	}

	repo.localWalletBalance[result.Type] = result

	return result, nil
}

func (repo *userWallet) BalancesXLock(ctx context.Context, kind []wallet.Types) ([]entity.Wallet, error) {
	var wallets []entity.Wallet

	err := repo.walletUserWhere(repo.uid, repo.asset).
		WithContext(ctx).
		Model(&entity.Wallet{}).
		Select("id, crypto, balance, type").
		Where("type IN ?", kind).
		Clauses(clause.Locking{Strength: "UPDATE"}).
		Find(&wallets).Error

	if err != nil {
		return []entity.Wallet{}, repository.WrapNotFoundError(err)
	}

	for _, w := range wallets {
		repo.localWalletBalance[w.Type] = w
	}

	return wallets, nil
}

func (repo *userWallet) XLock(ctx context.Context, id int64) (entity.Wallet, error) {
	var result entity.Wallet

	err := repo.db.WithContext(ctx).
		Model(&result).
		Select("id").
		Where("id = ?", id).
		Clauses(clause.Locking{Strength: "UPDATE"}).
		Take(&result).Error

	if err != nil {
		return entity.Wallet{}, repository.WrapNotFoundError(err)
	}

	repo.localWalletBalance[result.Type] = result

	return result, nil
}

func (repo *userWallet) XLocks(ctx context.Context, ids []int64) ([]entity.Wallet, error) {
	var wallets []entity.Wallet

	err := repo.db.WithContext(ctx).
		Model(&entity.Wallet{}).
		Select("id, crypto, balance, type").
		Where("id IN ?", ids).
		Clauses(clause.Locking{Strength: "UPDATE"}).
		Find(&wallets).Error

	if err != nil {
		return []entity.Wallet{}, repository.WrapNotFoundError(err)
	}

	for _, w := range wallets {
		repo.localWalletBalance[w.Type] = w
	}

	return wallets, nil
}

func (repo *userWallet) GetAvailableBalanceXLock(ctx context.Context, _ wallet.BusinessName) (entity.Wallet, error) {
	//switch b {
	//case domain.ContractBusinessTypeBusinessName, domain.SystemTransferBusinessTypeBusinessName:
	//	return repo.BalanceXLock(ctx, domain.WalletContractAvailableType)
	//case domain.ContractSimulationBusinessTypeBusinessName:
	//	return repo.BalanceXLock(ctx, domain.WalletSimulationAvailableType)
	//}

	return repo.BalanceXLock(ctx, wallet.TypeAvailable)
}

func (repo *userWallet) GetFreezeBalanceXLock(ctx context.Context, _ wallet.BusinessName) (entity.Wallet, error) {
	//switch b {
	//case domain.ContractBusinessTypeBusinessName, domain.SystemTransferBusinessTypeBusinessName, domain.SystemTransferCommissionBusinessTypeBusinessName:
	//	return w.Balance(ctx, domain.WalletContractFreezeType)
	//case domain.ContractSimulationBusinessTypeBusinessName:
	//	return w.Balance(ctx, domain.WalletSimulationFreezeType)
	//}

	return repo.Balance(ctx, wallet.TypeFreeze)
}

func (repo *userWallet) GetUnconfirmedBalanceXLock(ctx context.Context) (entity.Wallet, error) {
	return repo.BalanceXLock(ctx, wallet.TypeUnconfirmed)
}

func (repo *userWallet) GetOrderBalanceXLock(ctx context.Context, id int64) (entity.Transaction, error) {
	var result entity.Transaction

	err := repo.db.WithContext(ctx).
		Model(&result).
		Select("id, transaction_id, order_id, uid, crypto, balance, type, business_type").
		Where("id = ?", id).
		Clauses(clause.Locking{Strength: "UPDATE"}).
		Take(&result).Error

	if err != nil {
		return entity.Transaction{}, repository.WrapNotFoundError(err)
	}

	repo.localOrderBalance[result.ID] = result.Balance

	return result, nil
}

func (repo *userWallet) AddBalance(kind wallet.Types, amount decimal.Decimal) error {
	return repo.AddBalanceSetOrderID("", kind, amount)
}

func (repo *userWallet) AddBalanceSetOrderID(orderID string, kind wallet.Types, amount decimal.Decimal) error {
	w, ok := repo.localWalletBalance[kind]
	if !ok {
		return repository.ErrRecordNotFound
	}

	w.Balance = w.Balance.Add(amount)
	if w.Balance.LessThan(decimal.Zero) {
		return repository.ErrBalanceInsufficient
	}

	repo.transactions = append(repo.transactions, entity.WalletTransaction{
		OrderID:    orderID,
		UID:        repo.uid,
		WalletType: kind,
		Asset:      repo.asset,
		Amount:     amount,
		Balance:    w.Balance,
	})

	repo.localWalletBalance[kind] = w

	return nil
}

func (repo *userWallet) AddAvailable(_ wallet.BusinessName, amount decimal.Decimal) error {
	//switch b {
	//case domain.ContractBusinessTypeBusinessName, domain.SystemTransferBusinessTypeBusinessName:
	//	return w.AddBalance(domain.WalletContractAvailableType, amount)
	//case domain.ContractSimulationBusinessTypeBusinessName:
	//	return w.AddBalance(domain.WalletSimulationAvailableType, amount)
	//case domain.DistributionBusinessTypeBusinessName:
	//	return w.AddBalance(domain.WalletAvailableType, amount)
	//}

	return repo.AddBalance(wallet.TypeAvailable, amount)
}

func (repo *userWallet) AddFreeze(_ wallet.BusinessName, amount decimal.Decimal) error {
	//switch b {
	//case domain.ContractBusinessTypeBusinessName, domain.SystemTransferBusinessTypeBusinessName:
	//	return w.AddBalance(domain.WalletContractFreezeType, amount)
	//case domain.ContractSimulationBusinessTypeBusinessName:
	//	return w.AddBalance(domain.WalletSimulationFreezeType, amount)
	//}

	return repo.AddBalance(wallet.TypeFreeze, amount)
}

func (repo *userWallet) AddUnconfirmed(amount decimal.Decimal) error {
	return repo.AddBalance(wallet.TypeUnconfirmed, amount)
}

func (repo *userWallet) AddOrder(id int64, amount decimal.Decimal) error {
	return repo.addOrderBalance(id, amount)
}

func (repo *userWallet) SubAvailable(_ wallet.BusinessName, amount decimal.Decimal) error {
	//switch b {
	//case domain.ContractBusinessTypeBusinessName, domain.SystemTransferBusinessTypeBusinessName:
	//	return w.AddBalance(domain.WalletContractAvailableType, decimal.Zero.Sub(amount))
	//case domain.ContractSimulationBusinessTypeBusinessName:
	//	return w.AddBalance(domain.WalletSimulationAvailableType, decimal.Zero.Sub(amount))
	//}

	return repo.AddBalance(wallet.TypeAvailable, decimal.Zero.Sub(amount))
}

func (repo *userWallet) SubFreeze(_ wallet.BusinessName, amount decimal.Decimal) error {
	//switch b {
	//case domain.ContractBusinessTypeBusinessName, domain.SystemTransferBusinessTypeBusinessName, domain.SystemTransferCommissionBusinessTypeBusinessName:
	//	return w.AddBalance(domain.WalletContractFreezeType, decimal.Zero.Sub(amount))
	//case domain.ContractSimulationBusinessTypeBusinessName:
	//	return w.AddBalance(domain.WalletSimulationFreezeType, decimal.Zero.Sub(amount))
	//}

	return repo.AddBalance(wallet.TypeFreeze, decimal.Zero.Sub(amount))
}

func (repo *userWallet) SubUnconfirmed(amount decimal.Decimal) error {
	return repo.AddBalance(wallet.TypeUnconfirmed, decimal.Zero.Sub(amount))
}

func (repo *userWallet) GetAvailableBalance(ctx context.Context, _ wallet.BusinessName) (entity.Wallet, error) {
	//switch b {
	//case domain.ContractBusinessTypeBusinessName, domain.SystemTransferBusinessTypeBusinessName:
	//	return w.Balance(ctx, domain.WalletContractAvailableType)
	//case domain.ContractSimulationBusinessTypeBusinessName:
	//	return w.Balance(ctx, domain.WalletSimulationAvailableType)
	//case domain.DistributionBusinessTypeBusinessName:
	//	return w.Balance(ctx, domain.WalletAvailableType)
	//}

	return repo.Balance(ctx, wallet.TypeAvailable)
}

func (repo *userWallet) GetFreezeBalance(ctx context.Context, _ wallet.BusinessName) (entity.Wallet, error) {
	//switch b {
	//case domain.ContractBusinessTypeBusinessName, domain.SystemTransferBusinessTypeBusinessName, domain.SystemTransferCommissionBusinessTypeBusinessName:
	//	return w.Balance(ctx, domain.WalletContractFreezeType)
	//case domain.ContractSimulationBusinessTypeBusinessName:
	//	return w.Balance(ctx, domain.WalletSimulationFreezeType)
	//}

	return repo.Balance(ctx, wallet.TypeFreeze)
}

func (repo *userWallet) GetUnconfirmedBalance(ctx context.Context) (entity.Wallet, error) {
	return repo.Balance(ctx, wallet.TypeUnconfirmed)
}

func (repo *userWallet) GetOrderBalance(ctx context.Context, orderID string) (entity.Transaction, error) {
	var result entity.Transaction

	err := repo.db.WithContext(ctx).
		Model(&result).
		Select("id, transaction_id, order_id, uid, crypto, balance, type, business_type").
		Where("order_id = ?", orderID).
		Take(&result).Error

	if err != nil {
		return entity.Transaction{}, repository.WrapNotFoundError(err)
	}

	// 要確實set這兩個Balance，不然在做計算會有問題
	repo.localOrderBalance[result.ID] = result.Balance

	return result, nil
}

func (repo *userWallet) CheckWallet(ctx context.Context) (bool, error) {
	var exists bool
	err := repo.walletUserWhere(repo.uid, repo.asset).WithContext(ctx).
		Model(&entity.Wallet{}).
		Select("1").
		Where("type = ?", wallet.TypeAvailable).
		Limit(1).
		Scan(&exists).Error

	if err != nil {
		return false, err
	}

	return exists, nil
}

func (repo *userWallet) Execute(ctx context.Context) error {
	// 處理wallet table
	for _, walletType := range wallet.AllTypes {
		w, ok := repo.localWalletBalance[walletType]
		if !ok {
			continue
		}

		rc := &sql.TxOptions{
			Isolation: sql.LevelReadCommitted,
			ReadOnly:  false,
		}
		err := repo.db.Transaction(func(tx *gorm.DB) error {
			return tx.WithContext(ctx).
				Model(&entity.Wallet{}).
				Where("id = ?", w.ID).
				UpdateColumns(map[string]interface{}{
					"balance":     w.Balance,
					"update_time": time.Now().UTC().Unix(),
				}).Error
		}, rc)

		if err != nil {
			err = fmt.Errorf("update uid: %s crypto: %s type: %d wallet error: %w", repo.uid, repo.asset, walletType, err)

			return err
		}
	}

	return nil
}

func (repo *userWallet) ExecuteOrder(ctx context.Context) error {
	for id, localBalance := range repo.localOrderBalance {
		rc := &sql.TxOptions{
			Isolation: sql.LevelReadCommitted,
			ReadOnly:  false,
		}

		err := repo.db.Transaction(func(tx *gorm.DB) error {
			return tx.WithContext(ctx).
				Where("id = ?", id).
				Model(&entity.Transaction{}).
				Update("balance", localBalance).Error
		}, rc)

		if err != nil {
			return err
		}
	}

	return nil
}

func (repo *userWallet) Transactions(txID int64, orderID, brand string, businessType wallet.BusinessName) []entity.WalletTransaction {
	for i := range repo.transactions {
		repo.transactions[i].TransactionID = txID
		repo.transactions[i].OrderID = orderID
		repo.transactions[i].Brand = brand
		repo.transactions[i].BusinessType = businessType.ToINT8()
	}

	return repo.transactions
}

func (repo *userWallet) GetTransactions() []entity.WalletTransaction {
	return repo.transactions
}

// ============================================================================

func (repo *userWallet) walletUserWhere(uid, asset string) *gorm.DB {
	return repo.db.Where("uid = ?", uid).
		Where("asset = ?", asset)
}

// addOrderBalance  新增訂單餘額
// 使用前local Balance必須有資料，所以必須執行過GetOrderBalanceXLock才會有資料
func (repo *userWallet) addOrderBalance(id int64, amount decimal.Decimal) error {
	balance, ok := repo.localOrderBalance[id]
	if !ok {
		return repository.ErrRecordNotFound
	}

	balance = balance.Add(amount)
	if balance.LessThan(decimal.Zero) {
		return repository.ErrBalanceInsufficient
	}

	repo.localOrderBalance[id] = balance

	return nil
}