stack/components/payments/internal/models/account.go

package models

import (
	"database/sql/driver"
	"encoding/base64"
	"encoding/json"
	"errors"
	"fmt"
	"time"

	"github.com/gibson042/canonicaljson-go"
	"github.com/uptrace/bun"
)

type Account struct {
	bun.BaseModel `bun:"accounts.account"`

	ID           AccountID   `bun:",pk,type:character varying,nullzero"`
	ConnectorID  ConnectorID `bun:",type:character varying"`
	CreatedAt    time.Time   `bun:",nullzero"`
	Reference    string
	DefaultAsset Asset  `bun:"default_currency"` // Is optional and default to ''
	AccountName  string // Is optional and default to ''
	Type         AccountType
	Metadata     map[string]string

	RawData json.RawMessage

	PoolAccounts []*PoolAccounts `bun:"rel:has-many,join:id=account_id"`
}

type AccountType string

const (
	AccountTypeUnknown AccountType = "UNKNOWN"
	// Refers to an account that is internal to the psp, an account that we
	// can actually fetch the balance.
	AccountTypeInternal AccountType = "INTERNAL"
	// Refers to an external accounts such as user's bank accounts.
	AccountTypeExternal AccountType = "EXTERNAL"
	// Refers to an external accounts created inside formance database.
	// This is used only internally and will be transformed to EXTERNAL when
	// returned to the user.
	AccountTypeExternalFormance AccountType = "EXTERNAL_FORMANCE"
)

func (at AccountType) String() string {
	return string(at)
}

func AccountTypeFromString(t string) (AccountType, error) {
	switch t {
	case AccountTypeInternal.String():
		return AccountTypeInternal, nil
	case AccountTypeExternal.String():
		return AccountTypeExternal, nil
	case AccountTypeExternalFormance.String():
		return AccountTypeExternalFormance, nil
	}

	return AccountTypeUnknown, fmt.Errorf("unknown account type: %s", t)
}

type AccountID struct {
	Reference   string
	ConnectorID ConnectorID
}

func (aid *AccountID) String() string {
	if aid == nil || aid.Reference == "" {
		return ""
	}

	data, err := canonicaljson.Marshal(aid)
	if err != nil {
		panic(err)
	}

	return base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString(data)
}

func AccountIDFromString(value string) (*AccountID, error) {
	data, err := base64.URLEncoding.WithPadding(base64.NoPadding).DecodeString(value)
	if err != nil {
		return nil, err
	}
	ret := AccountID{}
	err = canonicaljson.Unmarshal(data, &ret)
	if err != nil {
		return nil, err
	}

	return &ret, nil
}

func MustAccountIDFromString(value string) AccountID {
	id, err := AccountIDFromString(value)
	if err != nil {
		panic(err)
	}
	return *id
}

func (aid AccountID) Value() (driver.Value, error) {
	return aid.String(), nil
}

func (aid *AccountID) Scan(value interface{}) error {
	if value == nil {
		return errors.New("account id is nil")
	}

	if s, err := driver.String.ConvertValue(value); err == nil {

		if v, ok := s.(string); ok {

			id, err := AccountIDFromString(v)
			if err != nil {
				return fmt.Errorf("failed to parse account id %s: %v", v, err)
			}

			*aid = *id
			return nil
		}
	}

	return fmt.Errorf("failed to scan account id: %v", value)
}