package ussd

import (
	"bytes"
	"context"
	"fmt"
	"path"
	"regexp"
	"strconv"
	"strings"

	"git.defalsify.org/vise.git/asm"
	"github.com/grassrootseconomics/eth-custodial/pkg/api"

	"git.defalsify.org/vise.git/cache"
	"git.defalsify.org/vise.git/db"
	"git.defalsify.org/vise.git/lang"
	"git.defalsify.org/vise.git/logging"
	"git.defalsify.org/vise.git/persist"
	"git.defalsify.org/vise.git/resource"
	"git.defalsify.org/vise.git/state"
	"git.grassecon.net/urdt/ussd/internal/handlers/server"
	"git.grassecon.net/urdt/ussd/internal/utils"
	"git.grassecon.net/urdt/ussd/common"
	"gopkg.in/leonelquinteros/gotext.v1"

	"git.grassecon.net/urdt/ussd/internal/storage"
)

var (
	logg           = logging.NewVanilla().WithDomain("ussdmenuhandler")
	scriptDir      = path.Join("services", "registration")
	translationDir = path.Join(scriptDir, "locale")
	okResponse     *api.OKResponse
	errResponse    *api.ErrResponse
	backOption     = []byte("0")
)

// FlagManager handles centralized flag management
type FlagManager struct {
	parser *asm.FlagParser
}

// NewFlagManager creates a new FlagManager instance
func NewFlagManager(csvPath string) (*FlagManager, error) {
	parser := asm.NewFlagParser()
	_, err := parser.Load(csvPath)
	if err != nil {
		return nil, fmt.Errorf("failed to load flag parser: %v", err)
	}

	return &FlagManager{
		parser: parser,
	}, nil
}

// GetFlag retrieves a flag value by its label
func (fm *FlagManager) GetFlag(label string) (uint32, error) {
	return fm.parser.GetFlag(label)
}

type Handlers struct {
	pe             *persist.Persister
	st             *state.State
	ca             cache.Memory
	userdataStore  utils.DataStore
	flagManager    *asm.FlagParser
	accountService server.AccountServiceInterface
}

func NewHandlers(appFlags *asm.FlagParser, userdataStore db.Db, accountService server.AccountServiceInterface) (*Handlers, error) {
	if userdataStore == nil {
		return nil, fmt.Errorf("cannot create handler with nil userdata store")
	}
	userDb := &utils.UserDataStore{
		Db: userdataStore,
	}
	h := &Handlers{
		userdataStore:  userDb,
		flagManager:    appFlags,
		accountService: accountService,
	}
	return h, nil
}

// Define the regex pattern as a constant
const pinPattern = `^\d{4}$`

// isValidPIN checks whether the given input is a 4 digit number
func isValidPIN(pin string) bool {
	match, _ := regexp.MatchString(pinPattern, pin)
	return match
}

func (h *Handlers) WithPersister(pe *persist.Persister) *Handlers {
	if h.pe != nil {
		panic("persister already set")
	}
	h.pe = pe
	return h
}

func (h *Handlers) Init(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var r resource.Result

	if h.pe == nil {
		logg.WarnCtxf(ctx, "handler init called before it is ready or more than once", "state", h.st, "cache", h.ca)
		return r, nil
	}
	h.st = h.pe.GetState()
	h.ca = h.pe.GetMemory()
	if h.st == nil || h.ca == nil {
		logg.ErrorCtxf(ctx, "perister fail in handler", "state", h.st, "cache", h.ca)
		return r, fmt.Errorf("cannot get state and memory for handler")
	}
	h.pe = nil

	logg.DebugCtxf(ctx, "handler has been initialized", "state", h.st, "cache", h.ca)

	return r, nil
}

// SetLanguage sets the language across the menu
func (h *Handlers) SetLanguage(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	symbol, _ := h.st.Where()
	code := strings.Split(symbol, "_")[1]

	if !utils.IsValidISO639(code) {
		return res, nil
	}
	res.FlagSet = append(res.FlagSet, state.FLAG_LANG)
	res.Content = code

	languageSetFlag, err := h.flagManager.GetFlag("flag_language_set")
	if err != nil {
		return res, err
	}
	res.FlagSet = append(res.FlagSet, languageSetFlag)

	return res, nil
}

func (h *Handlers) createAccountNoExist(ctx context.Context, sessionId string, res *resource.Result) error {
	flag_account_created, _ := h.flagManager.GetFlag("flag_account_created")
	okResponse, err := h.accountService.CreateAccount(ctx)
	if err != nil {
		return err
	}
	trackingId := okResponse.Result["trackingId"].(string)
	publicKey := okResponse.Result["publicKey"].(string)

	data := map[utils.DataTyp]string{
		utils.DATA_TRACKING_ID: trackingId,
		utils.DATA_PUBLIC_KEY:  publicKey,
	}
	store := h.userdataStore
	for key, value := range data {
		err = store.WriteEntry(ctx, sessionId, key, []byte(value))
		if err != nil {
			return err
		}
	}
	publicKeyNormalized, err := common.NormalizeHex(publicKey)
	if err != nil {
		return err
	}
	err = store.WriteEntry(ctx, publicKeyNormalized, utils.DATA_PUBLIC_KEY_REVERSE, []byte(sessionId))
	if err != nil {
		return err
	}
	res.FlagSet = append(res.FlagSet, flag_account_created)
	return nil

}

// CreateAccount checks if any account exists on the JSON data file, and if not
// creates an account on the API,
// sets the default values and flags
func (h *Handlers) CreateAccount(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	store := h.userdataStore
	_, err = store.ReadEntry(ctx, sessionId, utils.DATA_ACCOUNT_CREATED)
	if err != nil {
		if db.IsNotFound(err) {
			logg.Printf(logging.LVL_INFO, "Creating an account because it doesn't exist")
			err = h.createAccountNoExist(ctx, sessionId, &res)
			if err != nil {
				return res, err
			}
		}
	}
	return res, nil
}

func (h *Handlers) VerifyNewPin(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	res := resource.Result{}
	_, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	flag_valid_pin, _ := h.flagManager.GetFlag("flag_valid_pin")
	pinInput := string(input)
	// Validate that the PIN is a 4-digit number
	if isValidPIN(pinInput) {
		res.FlagSet = append(res.FlagSet, flag_valid_pin)
	} else {
		res.FlagReset = append(res.FlagReset, flag_valid_pin)
	}

	return res, nil
}

// SaveTemporaryPin saves the valid PIN input to the DATA_TEMPORARY_PIN
// during the account creation process
// and during the change PIN process
func (h *Handlers) SaveTemporaryPin(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	flag_incorrect_pin, _ := h.flagManager.GetFlag("flag_incorrect_pin")

	accountPIN := string(input)

	// Validate that the PIN is a 4-digit number
	if !isValidPIN(accountPIN) {
		res.FlagSet = append(res.FlagSet, flag_incorrect_pin)
		return res, nil
	}

	res.FlagReset = append(res.FlagReset, flag_incorrect_pin)

	store := h.userdataStore
	err = store.WriteEntry(ctx, sessionId, utils.DATA_TEMPORARY_PIN, []byte(accountPIN))
	if err != nil {
		return res, err
	}

	return res, nil
}

func (h *Handlers) ConfirmPinChange(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	flag_pin_mismatch, _ := h.flagManager.GetFlag("flag_pin_mismatch")

	store := h.userdataStore
	temporaryPin, err := store.ReadEntry(ctx, sessionId, utils.DATA_TEMPORARY_PIN)
	if err != nil {
		return res, err
	}
	if bytes.Equal(temporaryPin, input) {
		res.FlagReset = append(res.FlagReset, flag_pin_mismatch)
	} else {
		res.FlagSet = append(res.FlagSet, flag_pin_mismatch)
	}
	err = store.WriteEntry(ctx, sessionId, utils.DATA_ACCOUNT_PIN, []byte(temporaryPin))
	if err != nil {
		return res, err
	}
	return res, nil
}

// VerifyCreatePin checks whether the confirmation PIN is similar to the temporary PIN
// If similar, it sets the USERFLAG_PIN_SET flag and writes the account PIN allowing the user
// to access the main menu
func (h *Handlers) VerifyCreatePin(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	flag_valid_pin, _ := h.flagManager.GetFlag("flag_valid_pin")
	flag_pin_mismatch, _ := h.flagManager.GetFlag("flag_pin_mismatch")
	flag_pin_set, _ := h.flagManager.GetFlag("flag_pin_set")

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	store := h.userdataStore
	temporaryPin, err := store.ReadEntry(ctx, sessionId, utils.DATA_TEMPORARY_PIN)
	if err != nil {
		return res, err
	}

	if bytes.Equal(input, temporaryPin) {
		res.FlagSet = []uint32{flag_valid_pin}
		res.FlagReset = []uint32{flag_pin_mismatch}
		res.FlagSet = append(res.FlagSet, flag_pin_set)
	} else {
		res.FlagSet = []uint32{flag_pin_mismatch}
	}

	err = store.WriteEntry(ctx, sessionId, utils.DATA_ACCOUNT_PIN, []byte(temporaryPin))
	if err != nil {
		return res, err
	}

	return res, nil
}

// codeFromCtx retrieves language codes from the context that can be used for handling translations
func codeFromCtx(ctx context.Context) string {
	var code string
	if ctx.Value("Language") != nil {
		lang := ctx.Value("Language").(lang.Language)
		code = lang.Code
	}
	return code
}

// SaveFirstname updates the first name in the gdbm with the provided input.
func (h *Handlers) SaveFirstname(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	if len(input) > 0 {
		if bytes.Equal(input, backOption) {
			return res, nil
		}
		firstName := string(input)
		store := h.userdataStore
		err = store.WriteEntry(ctx, sessionId, utils.DATA_FIRST_NAME, []byte(firstName))
		if err != nil {
			return res, err
		}
	}

	return res, nil
}

// SaveFamilyname updates the family name in the gdbm with the provided input.
func (h *Handlers) SaveFamilyname(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	if len(input) > 0 {
		if bytes.Equal(input, backOption) {
			return res, nil
		}
		familyName := string(input)
		store := h.userdataStore
		err = store.WriteEntry(ctx, sessionId, utils.DATA_FAMILY_NAME, []byte(familyName))
		if err != nil {
			return res, err
		}
	} else {
		return res, fmt.Errorf("a family name cannot be less than one character")
	}

	return res, nil
}

// SaveYOB updates the Year of Birth(YOB) in the gdbm with the provided input.
func (h *Handlers) SaveYob(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	if len(input) == 4 {
		yob := string(input)
		store := h.userdataStore
		err = store.WriteEntry(ctx, sessionId, utils.DATA_YOB, []byte(yob))
		if err != nil {
			return res, err
		}
	}

	return res, nil
}

// SaveLocation updates the location in the gdbm with the provided input.
func (h *Handlers) SaveLocation(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	if len(input) > 0 {
		if bytes.Equal(input, backOption) {
			return res, nil
		}
		location := string(input)
		store := h.userdataStore
		err = store.WriteEntry(ctx, sessionId, utils.DATA_LOCATION, []byte(location))
		if err != nil {
			return res, err
		}
	}

	return res, nil
}

// SaveGender updates the gender in the gdbm with the provided input.
func (h *Handlers) SaveGender(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	symbol, _ := h.st.Where()
	var res resource.Result
	var err error
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	if bytes.Equal(input, backOption) {
		return res, nil
	}
	gender := strings.Split(symbol, "_")[1]
	store := h.userdataStore
	err = store.WriteEntry(ctx, sessionId, utils.DATA_GENDER, []byte(gender))
	if err != nil {
		return res, nil
	}

	return res, nil
}

// SaveOfferings updates the offerings(goods and services provided by the user) in the gdbm with the provided input.
func (h *Handlers) SaveOfferings(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	if len(input) > 0 {
		offerings := string(input)
		store := h.userdataStore
		err = store.WriteEntry(ctx, sessionId, utils.DATA_OFFERINGS, []byte(offerings))
		if err != nil {
			return res, nil
		}
	}

	return res, nil
}

// ResetAllowUpdate resets the allowupdate flag that allows a user to update  profile data.
func (h *Handlers) ResetAllowUpdate(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	flag_allow_update, _ := h.flagManager.GetFlag("flag_allow_update")

	res.FlagReset = append(res.FlagReset, flag_allow_update)
	return res, nil
}

// ResetAccountAuthorized resets the account authorization flag after a successful PIN entry.
func (h *Handlers) ResetAccountAuthorized(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	flag_account_authorized, _ := h.flagManager.GetFlag("flag_account_authorized")

	res.FlagReset = append(res.FlagReset, flag_account_authorized)
	return res, nil
}

// CheckIdentifier retrieves the PublicKey from the JSON data file.
func (h *Handlers) CheckIdentifier(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	store := h.userdataStore
	publicKey, _ := store.ReadEntry(ctx, sessionId, utils.DATA_PUBLIC_KEY)

	res.Content = string(publicKey)

	return res, nil
}

// Authorize attempts to unlock the next sequential nodes by verifying the provided PIN against the already set PIN.
// It sets the required flags that control the flow.
func (h *Handlers) Authorize(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	flag_incorrect_pin, _ := h.flagManager.GetFlag("flag_incorrect_pin")
	flag_account_authorized, _ := h.flagManager.GetFlag("flag_account_authorized")
	flag_allow_update, _ := h.flagManager.GetFlag("flag_allow_update")

	store := h.userdataStore
	AccountPin, err := store.ReadEntry(ctx, sessionId, utils.DATA_ACCOUNT_PIN)
	if err != nil {
		return res, err
	}
	if len(input) == 4 {
		if bytes.Equal(input, AccountPin) {
			if h.st.MatchFlag(flag_account_authorized, false) {
				res.FlagReset = append(res.FlagReset, flag_incorrect_pin)
				res.FlagSet = append(res.FlagSet, flag_allow_update, flag_account_authorized)
			} else {
				res.FlagSet = append(res.FlagSet, flag_allow_update)
				res.FlagReset = append(res.FlagReset, flag_account_authorized)
			}
		} else {
			res.FlagSet = append(res.FlagSet, flag_incorrect_pin)
			res.FlagReset = append(res.FlagReset, flag_account_authorized)
			return res, nil
		}
	} else {
		return res, nil
	}
	return res, nil
}

// ResetIncorrectPin resets the incorrect pin flag  after a new PIN attempt.
func (h *Handlers) ResetIncorrectPin(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	flag_incorrect_pin, _ := h.flagManager.GetFlag("flag_incorrect_pin")
	res.FlagReset = append(res.FlagReset, flag_incorrect_pin)
	return res, nil
}

// CheckAccountStatus queries the API using the TrackingId and sets flags
// based on the account status
func (h *Handlers) CheckAccountStatus(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	flag_account_success, _ := h.flagManager.GetFlag("flag_account_success")
	flag_account_pending, _ := h.flagManager.GetFlag("flag_account_pending")
	flag_api_error, _ := h.flagManager.GetFlag("flag_api_call_error")

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	store := h.userdataStore
	publicKey, err := store.ReadEntry(ctx, sessionId, utils.DATA_PUBLIC_KEY)
	if err != nil {
		return res, err
	}
	okResponse, err = h.accountService.TrackAccountStatus(ctx, string(publicKey))
	if err != nil {
		res.FlagSet = append(res.FlagSet, flag_api_error)
		return res, err
	}
	res.FlagReset = append(res.FlagReset, flag_api_error)
	isActive := okResponse.Result["active"].(bool)
	if !ok {
		return res, err
	}
	if isActive {
		res.FlagSet = append(res.FlagSet, flag_account_success)
		res.FlagReset = append(res.FlagReset, flag_account_pending)
	} else {
		res.FlagReset = append(res.FlagReset, flag_account_success)
		res.FlagSet = append(res.FlagSet, flag_account_pending)
	}
	return res, nil
}

// Quit displays the Thank you message and exits the menu
func (h *Handlers) Quit(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	flag_account_authorized, _ := h.flagManager.GetFlag("flag_account_authorized")

	code := codeFromCtx(ctx)
	l := gotext.NewLocale(translationDir, code)
	l.AddDomain("default")

	res.Content = l.Get("Thank you for using Sarafu. Goodbye!")
	res.FlagReset = append(res.FlagReset, flag_account_authorized)
	return res, nil
}

// QuitWithHelp displays helpline information then exits the menu
func (h *Handlers) QuitWithHelp(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	flag_account_authorized, _ := h.flagManager.GetFlag("flag_account_authorized")

	code := codeFromCtx(ctx)
	l := gotext.NewLocale(translationDir, code)
	l.AddDomain("default")

	res.Content = l.Get("For more help,please call: 0757628885")
	res.FlagReset = append(res.FlagReset, flag_account_authorized)
	return res, nil
}

// VerifyYob verifies the length of the given input
func (h *Handlers) VerifyYob(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error

	flag_incorrect_date_format, _ := h.flagManager.GetFlag("flag_incorrect_date_format")

	date := string(input)
	_, err = strconv.Atoi(date)
	if err != nil {
		// If conversion fails, input is not numeric
		res.FlagSet = append(res.FlagSet, flag_incorrect_date_format)
		return res, nil
	}

	if len(date) == 4 {
		res.FlagReset = append(res.FlagReset, flag_incorrect_date_format)
	} else {
		res.FlagSet = append(res.FlagSet, flag_incorrect_date_format)
	}

	return res, nil
}

// ResetIncorrectYob resets the incorrect date format flag after a new attempt
func (h *Handlers) ResetIncorrectYob(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	flag_incorrect_date_format, _ := h.flagManager.GetFlag("flag_incorrect_date_format")

	res.FlagReset = append(res.FlagReset, flag_incorrect_date_format)
	return res, nil
}

// CheckBalance retrieves the balance of the active voucher and sets
// the balance as the result content
func (h *Handlers) CheckBalance(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	code := codeFromCtx(ctx)
	l := gotext.NewLocale(translationDir, code)
	l.AddDomain("default")

	store := h.userdataStore

	// get the active sym and active balance
	activeSym, err := store.ReadEntry(ctx, sessionId, utils.DATA_ACTIVE_SYM)
	if err != nil {
		if db.IsNotFound(err) {
			balance := "0.00"
			res.Content = l.Get("Balance: %s\n", balance)
			return res, nil
		}

		return res, err
	}

	activeBal, err := store.ReadEntry(ctx, sessionId, utils.DATA_ACTIVE_BAL)
	if err != nil {
		return res, err
	}

	res.Content = l.Get("Balance: %s\n", fmt.Sprintf("%s %s", activeBal, activeSym))

	return res, nil
}

func (h *Handlers) FetchCustodialBalances(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	flag_api_error, _ := h.flagManager.GetFlag("flag_api_call_error")

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	symbol, _ := h.st.Where()
	balanceType := strings.Split(symbol, "_")[0]

	store := h.userdataStore
	publicKey, err := store.ReadEntry(ctx, sessionId, utils.DATA_PUBLIC_KEY)
	if err != nil {
		return res, err
	}

	balanceResponse, err := h.accountService.CheckBalance(ctx, string(publicKey))
	if err != nil {
		return res, nil
	}
	if !balanceResponse.Ok {
		res.FlagSet = append(res.FlagSet, flag_api_error)
		return res, nil
	}
	res.FlagReset = append(res.FlagReset, flag_api_error)
	balance := balanceResponse.Result.Balance

	switch balanceType {
	case "my":
		res.Content = fmt.Sprintf("Your balance is %s", balance)
	case "community":
		res.Content = fmt.Sprintf("Your community balance is %s", balance)
	default:
		break
	}
	return res, nil
}

// ValidateRecipient validates that the given input is a valid phone number.
func (h *Handlers) ValidateRecipient(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	recipient := string(input)

	flag_invalid_recipient, _ := h.flagManager.GetFlag("flag_invalid_recipient")

	if recipient != "0" {
		// mimic invalid number check
		if recipient == "000" {
			res.FlagSet = append(res.FlagSet, flag_invalid_recipient)
			res.Content = recipient

			return res, nil
		}
		store := h.userdataStore
		err = store.WriteEntry(ctx, sessionId, utils.DATA_RECIPIENT, []byte(recipient))
		if err != nil {
			return res, nil
		}
	}

	return res, nil
}

// TransactionReset resets the previous transaction data (Recipient and Amount)
// as well as the invalid flags
func (h *Handlers) TransactionReset(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	flag_invalid_recipient, _ := h.flagManager.GetFlag("flag_invalid_recipient")
	flag_invalid_recipient_with_invite, _ := h.flagManager.GetFlag("flag_invalid_recipient_with_invite")
	store := h.userdataStore
	err = store.WriteEntry(ctx, sessionId, utils.DATA_AMOUNT, []byte(""))
	if err != nil {
		return res, nil
	}

	err = store.WriteEntry(ctx, sessionId, utils.DATA_RECIPIENT, []byte(""))
	if err != nil {
		return res, nil
	}

	res.FlagReset = append(res.FlagReset, flag_invalid_recipient, flag_invalid_recipient_with_invite)

	return res, nil
}

// ResetTransactionAmount resets the transaction amount and invalid flag
func (h *Handlers) ResetTransactionAmount(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	flag_invalid_amount, _ := h.flagManager.GetFlag("flag_invalid_amount")
	store := h.userdataStore
	err = store.WriteEntry(ctx, sessionId, utils.DATA_AMOUNT, []byte(""))
	if err != nil {
		return res, nil
	}

	res.FlagReset = append(res.FlagReset, flag_invalid_amount)

	return res, nil
}

// MaxAmount gets the current balance from the API and sets it as
// the result content.
func (h *Handlers) MaxAmount(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	store := h.userdataStore

	activeBal, err := store.ReadEntry(ctx, sessionId, utils.DATA_ACTIVE_BAL)
	if err != nil {
		return res, err
	}

	res.Content = string(activeBal)

	return res, nil
}

// ValidateAmount ensures that the given input is a valid amount and that
// it is not more than the current balance.
func (h *Handlers) ValidateAmount(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	flag_invalid_amount, _ := h.flagManager.GetFlag("flag_invalid_amount")
	store := h.userdataStore

	var balanceValue float64

	// retrieve the active balance
	activeBal, err := store.ReadEntry(ctx, sessionId, utils.DATA_ACTIVE_BAL)
	if err != nil {
		return res, err
	}
	balanceValue, err = strconv.ParseFloat(string(activeBal), 64)
	if err != nil {
		return res, err
	}

	// Extract numeric part from the input amount
	amountStr := strings.TrimSpace(string(input))
	inputAmount, err := strconv.ParseFloat(amountStr, 64)
	if err != nil {
		res.FlagSet = append(res.FlagSet, flag_invalid_amount)
		res.Content = amountStr
		return res, nil
	}

	if inputAmount > balanceValue {
		res.FlagSet = append(res.FlagSet, flag_invalid_amount)
		res.Content = amountStr
		return res, nil
	}

	// Format the amount with 2 decimal places before saving
	formattedAmount := fmt.Sprintf("%.2f", inputAmount)
	err = store.WriteEntry(ctx, sessionId, utils.DATA_AMOUNT, []byte(formattedAmount))
	if err != nil {
		return res, err
	}

	res.Content = fmt.Sprintf("%s", formattedAmount)
	return res, nil
}

// GetRecipient returns the transaction recipient from the gdbm.
func (h *Handlers) GetRecipient(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	store := h.userdataStore
	recipient, _ := store.ReadEntry(ctx, sessionId, utils.DATA_RECIPIENT)

	res.Content = string(recipient)

	return res, nil
}

// GetSender returns the sessionId (phoneNumber)
func (h *Handlers) GetSender(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	res.Content = string(sessionId)

	return res, nil
}

// GetAmount retrieves the amount from teh Gdbm Db
func (h *Handlers) GetAmount(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	store := h.userdataStore

	// retrieve the active symbol
	activeSym, err := store.ReadEntry(ctx, sessionId, utils.DATA_ACTIVE_SYM)
	if err != nil {
		return res, err
	}

	amount, _ := store.ReadEntry(ctx, sessionId, utils.DATA_AMOUNT)

	res.Content = fmt.Sprintf("%s %s", string(amount), string(activeSym))

	return res, nil
}

// InitiateTransaction returns a confirmation and resets the transaction data
// on the gdbm store.
func (h *Handlers) InitiateTransaction(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	code := codeFromCtx(ctx)
	l := gotext.NewLocale(translationDir, code)
	l.AddDomain("default")
	// TODO
	// Use the amount, recipient and sender to call the API and initialize the transaction
	store := h.userdataStore

	amount, _ := store.ReadEntry(ctx, sessionId, utils.DATA_AMOUNT)

	recipient, _ := store.ReadEntry(ctx, sessionId, utils.DATA_RECIPIENT)

	activeSym, _ := store.ReadEntry(ctx, sessionId, utils.DATA_ACTIVE_SYM)

	res.Content = l.Get("Your request has been sent. %s will receive %s %s from %s.", string(recipient), string(amount), string(activeSym), string(sessionId))

	account_authorized_flag, err := h.flagManager.GetFlag("flag_account_authorized")
	if err != nil {
		return res, err
	}

	res.FlagReset = append(res.FlagReset, account_authorized_flag)
	return res, nil
}

func (h *Handlers) GetProfileInfo(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var defaultValue string
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}
	language, ok := ctx.Value("Language").(lang.Language)
	if !ok {
		return res, fmt.Errorf("value for 'Language' is not of type lang.Language")
	}
	code := language.Code
	if code == "swa" {
		defaultValue = "Haipo"
	} else {
		defaultValue = "Not Provided"
	}

	// Helper function to handle nil byte slices and convert them to string
	getEntryOrDefault := func(entry []byte, err error) string {
		if err != nil || entry == nil {
			return defaultValue
		}
		return string(entry)
	}
	store := h.userdataStore
	// Retrieve user data as strings with fallback to defaultValue
	firstName := getEntryOrDefault(store.ReadEntry(ctx, sessionId, utils.DATA_FIRST_NAME))
	familyName := getEntryOrDefault(store.ReadEntry(ctx, sessionId, utils.DATA_FAMILY_NAME))
	yob := getEntryOrDefault(store.ReadEntry(ctx, sessionId, utils.DATA_YOB))
	gender := getEntryOrDefault(store.ReadEntry(ctx, sessionId, utils.DATA_GENDER))
	location := getEntryOrDefault(store.ReadEntry(ctx, sessionId, utils.DATA_LOCATION))
	offerings := getEntryOrDefault(store.ReadEntry(ctx, sessionId, utils.DATA_OFFERINGS))

	// Construct the full name
	name := defaultValue
	if familyName != defaultValue {
		if firstName == defaultValue {
			name = familyName
		} else {
			name = firstName + " " + familyName
		}
	}

	// Calculate age from year of birth
	age := defaultValue
	if yob != defaultValue {
		if yobInt, err := strconv.Atoi(yob); err == nil {
			age = strconv.Itoa(utils.CalculateAgeWithYOB(yobInt))
		} else {
			return res, fmt.Errorf("invalid year of birth: %v", err)
		}
	}
	switch language.Code {
	case "eng":
		res.Content = fmt.Sprintf(
			"Name: %s\nGender: %s\nAge: %s\nLocation: %s\nYou provide: %s\n",
			name, gender, age, location, offerings,
		)
	case "swa":
		res.Content = fmt.Sprintf(
			"Jina: %s\nJinsia: %s\nUmri: %s\nEneo: %s\nUnauza: %s\n",
			name, gender, age, location, offerings,
		)
	default:
		res.Content = fmt.Sprintf(
			"Name: %s\nGender: %s\nAge: %s\nLocation: %s\nYou provide: %s\n",
			name, gender, age, location, offerings,
		)
	}

	return res, nil
}

// SetDefaultVoucher retrieves the current vouchers
// and sets the first as the default voucher, if no active voucher is set
func (h *Handlers) SetDefaultVoucher(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	store := h.userdataStore

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	flag_no_active_voucher, _ := h.flagManager.GetFlag("flag_no_active_voucher")

	// check if the user has an active sym
	_, err = store.ReadEntry(ctx, sessionId, utils.DATA_ACTIVE_SYM)

	if err != nil {
		if db.IsNotFound(err) {
			publicKey, err := store.ReadEntry(ctx, sessionId, utils.DATA_PUBLIC_KEY)
			if err != nil {
				return res, nil
			}

			// Fetch vouchers from the API using the public key
			vouchersResp, err := h.accountService.FetchVouchers(ctx, string(publicKey))
			if err != nil {
				return res, nil
			}

			// Return if there is no voucher
			if len(vouchersResp.Result.Holdings) == 0 {
				res.FlagSet = append(res.FlagSet, flag_no_active_voucher)
				return res, nil
			}

			// Use only the first voucher
			firstVoucher := vouchersResp.Result.Holdings[0]
			defaultSym := firstVoucher.TokenSymbol
			defaultBal := firstVoucher.Balance

			// set the active symbol
			err = store.WriteEntry(ctx, sessionId, utils.DATA_ACTIVE_SYM, []byte(defaultSym))
			if err != nil {
				return res, err
			}
			// set the active balance
			err = store.WriteEntry(ctx, sessionId, utils.DATA_ACTIVE_BAL, []byte(defaultBal))
			if err != nil {
				return res, err
			}

			return res, nil
		}

		return res, err
	}

	res.FlagReset = append(res.FlagReset, flag_no_active_voucher)

	return res, nil
}

// CheckVouchers retrieves the token holdings from the API using the "PublicKey" and stores
// them to gdbm
func (h *Handlers) CheckVouchers(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	store := h.userdataStore
	publicKey, err := store.ReadEntry(ctx, sessionId, utils.DATA_PUBLIC_KEY)
	if err != nil {
		return res, nil
	}

	// Fetch vouchers from the API using the public key
	vouchersResp, err := h.accountService.FetchVouchers(ctx, string(publicKey))
	if err != nil {
		return res, nil
	}

	// process voucher data
	voucherSymbolList, voucherBalanceList := ProcessVouchers(vouchersResp.Result.Holdings)

	prefixdb := storage.NewSubPrefixDb(store, []byte("vouchers"))
	err = prefixdb.Put(ctx, []byte("sym"), []byte(voucherSymbolList))
	if err != nil {
		return res, nil
	}

	err = prefixdb.Put(ctx, []byte("bal"), []byte(voucherBalanceList))
	if err != nil {
		return res, nil
	}

	return res, nil
}

// ProcessVouchers formats the holdings into symbol and balance lists.
func ProcessVouchers(holdings []struct {
	ContractAddress string `json:"contractAddress"`
	TokenSymbol     string `json:"tokenSymbol"`
	TokenDecimals   string `json:"tokenDecimals"`
	Balance         string `json:"balance"`
}) (string, string) {
	var numberedSymbols, numberedBalances []string

	for i, voucher := range holdings {
		numberedSymbols = append(numberedSymbols, fmt.Sprintf("%d:%s", i+1, voucher.TokenSymbol))
		numberedBalances = append(numberedBalances, fmt.Sprintf("%d:%s", i+1, voucher.Balance))
	}

	voucherSymbolList := strings.Join(numberedSymbols, "\n")
	voucherBalanceList := strings.Join(numberedBalances, "\n")

	return voucherSymbolList, voucherBalanceList
}

// GetVoucherList fetches the list of vouchers and formats them
func (h *Handlers) GetVoucherList(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result

	// Read vouchers from the store
	store := h.userdataStore
	prefixdb := storage.NewSubPrefixDb(store, []byte("vouchers"))

	voucherData, err := prefixdb.Get(ctx, []byte("sym"))
	if err != nil {
		return res, nil
	}

	res.Content = string(voucherData)

	return res, nil
}

// ViewVoucher retrieves the token holding and balance from the subprefixDB
func (h *Handlers) ViewVoucher(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	store := h.userdataStore

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	flag_incorrect_voucher, _ := h.flagManager.GetFlag("flag_incorrect_voucher")

	inputStr := string(input)

	if inputStr == "0" || inputStr == "99" {
		res.FlagReset = append(res.FlagReset, flag_incorrect_voucher)
		return res, nil
	}

	prefixdb := storage.NewSubPrefixDb(store, []byte("vouchers"))

	// Retrieve the voucher symbol list
	voucherSymbolList, err := prefixdb.Get(ctx, []byte("sym"))
	if err != nil {
		return res, fmt.Errorf("failed to retrieve voucher symbol list: %v", err)
	}

	// Retrieve the voucher balance list
	voucherBalanceList, err := prefixdb.Get(ctx, []byte("bal"))
	if err != nil {
		return res, fmt.Errorf("failed to retrieve voucher balance list: %v", err)
	}

	// match the voucher symbol and balance with the input
	matchedSymbol, matchedBalance := MatchVoucher(inputStr, string(voucherSymbolList), string(voucherBalanceList))

	// If a match is found, write the temporary sym and balance
	if matchedSymbol != "" && matchedBalance != "" {
		err = store.WriteEntry(ctx, sessionId, utils.DATA_TEMPORARY_SYM, []byte(matchedSymbol))
		if err != nil {
			return res, err
		}
		err = store.WriteEntry(ctx, sessionId, utils.DATA_TEMPORARY_BAL, []byte(matchedBalance))
		if err != nil {
			return res, err
		}

		res.FlagReset = append(res.FlagReset, flag_incorrect_voucher)
		res.Content = fmt.Sprintf("%s\n%s", matchedSymbol, matchedBalance)
	} else {
		res.FlagSet = append(res.FlagSet, flag_incorrect_voucher)
	}

	return res, nil
}

// MatchVoucher finds the matching voucher symbol and balance based on the input.
func MatchVoucher(inputStr string, voucherSymbols, voucherBalances string) (string, string) {
	// Split the lists into slices for processing
	symbols := strings.Split(voucherSymbols, "\n")
	balances := strings.Split(voucherBalances, "\n")

	var matchedSymbol, matchedBalance string

	for i, symbol := range symbols {
		symbolParts := strings.SplitN(symbol, ":", 2)
		if len(symbolParts) != 2 {
			continue
		}
		voucherNum := symbolParts[0]
		voucherSymbol := symbolParts[1]

		// Check if input matches either the number or the symbol
		if inputStr == voucherNum || strings.EqualFold(inputStr, voucherSymbol) {
			matchedSymbol = voucherSymbol
			// Ensure there's a corresponding balance
			if i < len(balances) {
				matchedBalance = strings.SplitN(balances[i], ":", 2)[1]
			}
			break
		}
	}

	return matchedSymbol, matchedBalance
}

// SetVoucher retrieves the temporary sym and balance,
// sets them as the active data and
// clears the temporary data
func (h *Handlers) SetVoucher(ctx context.Context, sym string, input []byte) (resource.Result, error) {
	var res resource.Result
	var err error
	store := h.userdataStore

	sessionId, ok := ctx.Value("SessionId").(string)
	if !ok {
		return res, fmt.Errorf("missing session")
	}

	// get the current temporary symbol
	temporarySym, err := store.ReadEntry(ctx, sessionId, utils.DATA_TEMPORARY_SYM)
	if err != nil {
		return res, err
	}
	// get the current temporary balance
	temporaryBal, err := store.ReadEntry(ctx, sessionId, utils.DATA_TEMPORARY_BAL)
	if err != nil {
		return res, err
	}

	// set the active symbol
	err = store.WriteEntry(ctx, sessionId, utils.DATA_ACTIVE_SYM, []byte(temporarySym))
	if err != nil {
		return res, err
	}
	// set the active balance
	err = store.WriteEntry(ctx, sessionId, utils.DATA_ACTIVE_BAL, []byte(temporaryBal))
	if err != nil {
		return res, err
	}

	// reset the temporary symbol
	err = store.WriteEntry(ctx, sessionId, utils.DATA_TEMPORARY_SYM, []byte(""))
	if err != nil {
		return res, err
	}
	// reset the temporary balance
	err = store.WriteEntry(ctx, sessionId, utils.DATA_TEMPORARY_BAL, []byte(""))
	if err != nil {
		return res, err
	}

	res.Content = string(temporarySym)

	return res, nil
}