Schemas

class Application(BaseModel):
    '''Application info.

    Attributes:
        app_id (int): Application unique ID.
        name (str): Application name.
        payment_processing_bot_username (str): Username of Crypto bot.
    '''
    app_id: int
    name: str
    payment_processing_bot_username: str

class Assets(Enum):
    '''Currency code.

    Attributes:
        BTC (str): Bitcoin
        TON (str): Toncoin
        ETH (str): Ethereum
        USDT (str): Tether
        USDC (str): USD Coin
        BUSD (str): Binance USD
    '''
    BTC = 'BTC'
    TON = 'TON'
    ETH = 'ETH'
    USDT = 'USDT'
    USDC = 'USDC'
    BUSD = 'BUSD'

    def __str__(self) -> str:
        return self.value

class Balance(BaseModel):
    '''Balance info.

    Attributes:
        currency_code (str): Currency code.
        available (Decimal): Available for using.
    '''
    currency_code: str
    available: Decimal

class Currency(BaseModel):
    '''Currency info.

    Attributes:
        is_blockchain (bool): Is blockchain asset?
        is_stablecoin (bool): Is stable coin?
        is_fiat (bool): Is fiat asset?
        name (str): Name of currency.
        code (str): Code of currency.
        url (Optional[str]): *Optional*. URL of currency site.
        decimals (int): ?
    '''
    is_blockchain: bool
    is_stablecoin: bool
    is_fiat: bool
    name: str
    code: str
    url: Optional[str]
    decimals: int

class ExchangeRate(BaseModel):
    '''Exchange rate info.

    Attributes:
        is_valid (bool): Is valid?
        source (str): Source asset.
        target (str): Target asset.
        rate (Decimal): Exchange rate.
    '''
    is_valid: bool
    source: str
    target: str
    rate: Decimal

class Invoice(BaseModel):
    '''Invoice info.

    Attributes:
        invoice_id (int): Unique ID for this invoice.
        status (InvoiceStatus): Status of the invoice.
        hash (str): Hash of the invoice.
        asset (Assets): Currency code.
        amount (Decimal): Amount of the invoice.
        pay_url (str): URL should be presented to the user to pay the invoice.
        description (Optional[str]): *Optional*. Description for this invoice.
        created_at (datetime): Date the invoice was created in ISO 8601 format.
        allow_comments (bool): `True`, if the user can add comment to the payment.
        allow_anonymous (bool): `True`, if the user can pay the invoice anonymously.
        expiration_date (Optional[datetime]): *Optional*. Date the invoice expires in Unix time.
        paid_at (Optional[datetime]): *Optional*. Date the invoice was paid in Unix time.
        paid_anonymously (Optional[bool]): `True`, if the invoice was paid anonymously.
        comment (Optional[str]): *Optional*. Comment to the payment from the user.
        hidden_message (Optional[str]): *Optional*. Text of the hidden message for this invoice.
        payload (Optional[str]): *Optional*. Previously provided data for this invoice.
        paid_btn_name (Optional[PaidButtonNames]): *Optional*. Name of the button.
        paid_btn_url (Optional[str]): *Optional*. URL of the button.
        fee (Optional[Decimal]): *Optional*. Amount of charged service fees. Returned only if the invoice has paid status.
        usd_rate (Optional[Decimal]): *Optional*. Price of the asset in USD. Returned only if the invoice has paid status.
    '''
    invoice_id: int
    status: InvoiceStatus
    hash: str
    asset: Assets
    amount: Decimal
    pay_url: str
    description: Optional[str]
    created_at: datetime
    allow_comments: bool
    allow_anonymous: bool
    expiration_date: Optional[datetime]
    paid_at: Optional[datetime]
    paid_anonymously: Optional[bool]
    comment: Optional[str]
    hidden_message: Optional[str]
    payload: Optional[str]
    paid_btn_name: Optional[PaidButtonNames]
    paid_btn_url: Optional[str]
    fee: Optional[Decimal]
    usd_rate: Optional[Decimal]

class InvoiceStatus(Enum):
    '''Status of invoice.

    Attributes:
        ACTIVE (str): 'active'
        PAID (str): 'paid'
        EXPIRED (str): 'expired'
    '''
    ACTIVE = 'active'
    PAID = 'paid'
    EXPIRED = 'expired'

    def __str__(self) -> str:
        return self.value

class PaidButtonNames(Enum):
    '''Name of the button.

    Attributes:
        VIEW_ITEM (str): 'viewItem'
        OPEN_CHANNEL (str): 'openChannel'
        OPEN_BOT (str): 'openBot'
        CALLBACK (str): 'callback'
    '''
    VIEW_ITEM = 'viewItem'
    OPEN_CHANNEL = 'openChannel'
    OPEN_BOT = 'openBot'
    CALLBACK = 'callback'

    def __str__(self) -> str:
        return self.value

class Transfer(BaseModel):
    '''Transfer info.

    Attributes:
        transfer_id (int): Unique ID for this transfer.
        user_id (int): Telegram user ID the transfer was sent to.
        asset (Assets): Currency code.
        amount (Decimal): Amount of the transfer.
        status (Literal['completed']): Status of the transfer, can be “completed”.
        completed_at (datetime): Date the transfer was completed in ISO 8601 format.
        comment (Optional[str]): *Optional*. Comment for this transfer.
    '''
    transfer_id: int
    user_id: int
    asset: Assets
    amount: Decimal
    status: Literal['completed']
    completed_at: datetime
    comment: Optional[str]

class Update(BaseModel):
    '''Webhook update object.

    Attributes:
        update_id (int): Non-unique update ID.
        update_type (UpdateType): Webhook update type.
        request_date (datetime): Date the request was sent in ISO 8601 format.
        payload (Invoice): Payload contains `Invoice` object.
        raw_body (Optional[bytes]): *Optional*. Raw body of update, for check sign purpose.
    '''
    update_id: int
    update_type: UpdateType
    request_date: datetime
    payload: Invoice
    raw_body: Optional[bytes] = None

    def check_signature(self, api_key: str, sign: str) -> bool:
        '''Check update signature.

        Args:
            api_key (str): CryptoPay app API key.
            sign (str): Update signature. In request headers `crypto-pay-api-signature`.

        Returns:
            bool: Is signature verified?
        '''
        log.debug(f'Called with args: ({api_key}, {sign})')
        secret = sha256(api_key.encode()).digest()
        hmac = HMAC(secret, self.raw_body, digestmod=sha256)
        body_sign = hmac.hexdigest()
        log.debug(f'Calculated hash: {body_sign}')
        return body_sign == sign

class UpdateType(Enum):
    '''Webhook update type.

    Attributes:
        INVOICE_PAID (str): 'invoice_paid
    '''
    INVOICE_PAID = 'invoice_paid'