wallet-go-api/pkg/services/wallets.go

package services

import (
	"sync"
	"time"
	"wallet-api/pkg/models"
	"wallet-api/pkg/utl/common"

	"github.com/go-pg/pg/v10"
)

type WalletService struct {
	Db *pg.DB
}

func (as *WalletService) New(am *models.NewWalletBody) *models.Wallet {

	walletModel := new(models.Wallet)
	walletModel.Init()
	walletModel.UserID = am.UserID
	walletModel.Name = am.Name
	as.Db.Model(walletModel).Insert()
	return walletModel
}

func (as *WalletService) Get(am *models.Auth, embed string) *models.Wallet {
	wm := new(models.Wallet)

	query := as.Db.Model(wm).Where("? = ?", pg.Ident("user_id"), am.Id)
	common.GenerateEmbed(query, embed).Select()

	return wm
}

func (as *WalletService) GetAll(am *models.Auth, filtered *models.FilteredResponse) {
	wm := new([]models.Wallet)

	query := as.Db.Model(wm).Where("? = ?", pg.Ident("user_id"), am.Id)
	FilteredResponse(query, wm, filtered)
}

func (as *WalletService) GetHeader(am *models.Auth, embed string, walletId string) *models.WalletHeader {
	wm := new(models.WalletHeader)
	var wallets []models.WalletTransactions
	var wg sync.WaitGroup
	transactions := new([]models.Transaction)
	subscriptions := new([]models.Subscription)

	wg.Add(1)
	go func() {
		defer wg.Done()
		query := as.Db.Model(transactions).Relation("Wallet").Where("wallet.? = ?", pg.Ident("user_id"), am.Id).Relation("TransactionType")
		if walletId != "" {
			query.Where("? = ?", pg.Ident("wallet_id"), walletId)
		}
		query.Select()
	}()
	wg.Add(1)
	go func() {
		defer wg.Done()
		query2 := as.Db.Model(subscriptions).Relation("Wallet").Where("wallet.? = ?", pg.Ident("user_id"), am.Id).Relation("TransactionType").Relation("SubscriptionType")
		if walletId != "" {
			query2.Where("? = ?", pg.Ident("wallet_id"), walletId)
		}
		query2.Select()
	}()

	wg.Wait()

	currentBalance := 0
	lastMonthBalance := 0
	nextMonth := 0

	subCurrentBalance := 0
	subLastMonthBalance := 0
	subNextMonth := 0

	now := time.Now()

	currentYear, currentMonth, _ := now.Date()
	currentLocation := now.Location()

	firstOfMonth := time.Date(currentYear, currentMonth, 1, 0, 0, 0, 0, currentLocation)
	firstOfNextMonth := time.Date(currentYear, currentMonth+1, 1, 0, 0, 0, 0, currentLocation)
	firstOfMonthAfterNext := time.Date(currentYear, currentMonth+2, 1, 0, 0, 0, 0, currentLocation)

	for _, trans := range *transactions {
		addWhere(&wallets, trans.WalletID, trans)
	}

	for _, sub := range *subscriptions {
		startDate := sub.StartDate
		for startDate.Before(firstOfMonthAfterNext) {
			trans := sub.ToTrans()
			trans.TransactionDate = startDate
			addWhere(&wallets, sub.WalletID, *trans)
			if sub.SubscriptionType.Type == "monthly" {
				startDate = startDate.AddDate(0, sub.CustomRange, 0)
			} else if sub.SubscriptionType.Type == "weekly" {
				startDate = startDate.AddDate(0, 0, 7*sub.CustomRange)
			} else if sub.SubscriptionType.Type == "daily" {
				startDate = startDate.AddDate(0, 0, sub.CustomRange)
			} else {
				startDate = startDate.AddDate(sub.CustomRange, 0, 0)
			}
		}
	}

	for _, wallet := range wallets {
		wg.Add(1)
		go func() {
			defer wg.Done()
			for _, trans := range wallet.Transactions {
				if trans.TransactionDate.Before(firstOfNextMonth) && trans.TransactionDate.After(firstOfMonth) {
					if trans.TransactionType.Type == "expense" {
						currentBalance -= trans.Amount
					} else {
						currentBalance += trans.Amount
					}
				} else if trans.TransactionDate.Before(firstOfMonthAfterNext) && trans.TransactionDate.After(firstOfNextMonth) {
					if trans.TransactionType.Type == "expense" {
						nextMonth -= trans.Amount
					} else {
						nextMonth += trans.Amount
					}
				} else if trans.TransactionDate.Before(firstOfMonth) {
					if trans.TransactionType.Type == "expense" {
						lastMonthBalance -= trans.Amount
					} else {
						lastMonthBalance += trans.Amount
					}
				}
			}
		}()
	}

	// for _, sub := range *subscriptions {
	// 	wg.Add(1)
	// 	go func() {
	// 		defer wg.Done()
	// 		startDate := sub.StartDate
	// 		now := time.Now()
	// 		for startDate.Before(now) {
	// 			if startDate.Before(firstOfNextMonth) && startDate.After(firstOfMonth) {
	// 				if sub.TransactionType.Type == "expense" {
	// 					subCurrentBalance -= sub.Amount
	// 				} else {
	// 					subCurrentBalance += sub.Amount
	// 				}
	// 			} else if startDate.Before(firstOfMonthAfterNext) && startDate.After(firstOfNextMonth) {
	// 				if sub.TransactionType.Type == "expense" {
	// 					subNextMonth -= sub.Amount
	// 				} else {
	// 					subNextMonth += sub.Amount
	// 				}
	// 			} else if startDate.Before(firstOfMonth) {
	// 				if sub.TransactionType.Type == "expense" {
	// 					subLastMonthBalance -= sub.Amount
	// 				} else {
	// 					subLastMonthBalance += sub.Amount
	// 				}
	// 			}

	// 		}
	// 	}()
	// }

	wg.Wait()

	combinedCurrent := currentBalance + subCurrentBalance
	combinedLast := lastMonthBalance + subLastMonthBalance
	combinedNext := nextMonth + subNextMonth

	wm.LastMonth = combinedLast
	wm.CurrentBalance = combinedCurrent + combinedLast
	wm.NextMonth = combinedLast + combinedCurrent + combinedNext
	wm.Currency = "USD"
	wm.WalletId = walletId

	//common.GenerateEmbed(query, embed).Select()

	return wm
}

func addWhere(s *[]models.WalletTransactions, walletId string, e models.Transaction) {
	var exists bool
	for a, _ := range *s {
		if (*s)[a].WalletId == walletId {
			(*s)[a].Transactions = append((*s)[a].Transactions, e)
		}
		exists = true
	}
	if !exists {
		var walletTransaction models.WalletTransactions
		walletTransaction.WalletId = walletId
		walletTransaction.Transactions = append(walletTransaction.Transactions, e)
		*s = append(*s, walletTransaction)
	}
}