@spec base_url() :: String.t()

Returns the base URL for NBU QR codes.

Used in V002 and V003 formats to generate URLs with Base64URL encoded data.

@spec currency() :: String.t()

Returns the default currency code (UAH).

Currently only UAH (Ukrainian Hryvnia) is supported.

@spec encoding_code(:utf8 | :cp1251) :: pos_integer()

Returns the encoding code for the given encoding type.

Encoding Codes

• :utf8 → 1
• :cp1251 → 2

Examples

iex> QRNBU.Constants.encoding_code(:utf8)
1

iex> QRNBU.Constants.encoding_code(:cp1251)
2

@spec encoding_from_code(pos_integer()) :: :utf8 | :cp1251 | {:error, String.t()}

Returns the encoding atom for a given encoding code.

Examples

iex> QRNBU.Constants.encoding_from_code(1)
:utf8

iex> QRNBU.Constants.encoding_from_code(2)
:cp1251

@spec format_version(pos_integer()) :: String.t()

Returns the version format number padded to 3 digits.

Examples

iex> QRNBU.Constants.format_version(1)
"001"

iex> QRNBU.Constants.format_version(2)
"002"

iex> QRNBU.Constants.format_version(3)
"003"

@spec iban_length() :: pos_integer()

Returns the IBAN length for Ukraine.

Ukrainian IBANs are always exactly 29 characters.

@spec label() :: String.t()

Returns the format label (BCD - Banking QR Code Data).

This is the first line of all NBU QR codes.

@spec line_ending(pos_integer()) :: String.t()

Returns the line ending character(s) for a given version.

Line Endings

• V001/V002: CRLF (\r\n) - Windows-style
• V003: LF (\n) - Unix-style

Examples

iex> QRNBU.Constants.line_ending(1)
"\r\n"

iex> QRNBU.Constants.line_ending(3)
"\n"

@spec max_purpose_length(pos_integer()) :: pos_integer()

Returns the maximum payment purpose length for a given version.

Limits

• V001/V002: 140 characters
• V003: 280 characters

Examples

iex> QRNBU.Constants.max_purpose_length(2)
140

iex> QRNBU.Constants.max_purpose_length(3)
280

@spec max_recipient_length(pos_integer()) :: pos_integer()

Returns the maximum recipient name length for a given version.

Limits

• V001/V002: 70 characters
• V003: 140 characters

Examples

iex> QRNBU.Constants.max_recipient_length(1)
70

iex> QRNBU.Constants.max_recipient_length(3)
140

@spec service_ict() :: String.t()

Returns the service type code for ICT (Instant Credit Transfer).

Only available in V003 format.

@spec service_types() :: [String.t()]

Returns all supported service types.

Service Types

• UCT - Universal Credit Transfer (standard payment)
• ICT - Instant Credit Transfer (instant payment, V003 only)
• XCT - Extended Credit Transfer (reserved for future use)

@spec service_uct() :: String.t()

Returns the service type code for UCT (Universal Credit Transfer).

This is the default service type for V001 and V002.

@spec service_xct() :: String.t()

Returns the service type code for XCT (Extended Credit Transfer).

Reserved for future use.

@spec supported_currencies() :: [String.t()]

Returns all supported currency codes.

Currently only UAH is supported per NBU specification.

@spec supported_versions() :: [pos_integer()]

Returns all supported version numbers.

Versions

• 1 - V001 (legacy format, 9 fields)
• 2 - V002 (URL-based format, 9 fields)
• 3 - V003 (latest format, 17 fields)

@spec valid_service_for_version?(String.t(), pos_integer()) :: boolean()

Validates if a service type is supported for a given version.

Service Type Availability

• V001/V002: UCT only
• V003: UCT, ICT, XCT

Examples

iex> QRNBU.Constants.valid_service_for_version?("UCT", 1)
true

iex> QRNBU.Constants.valid_service_for_version?("ICT", 2)
false

iex> QRNBU.Constants.valid_service_for_version?("ICT", 3)
true