package jwt

// Claims represent any form of a JWT Claims Set according to
// https://datatracker.ietf.org/doc/html/rfc7519#section-4. In order to have a
// common basis for validation, it is required that an implementation is able to
// supply at least the claim names provided in
// https://datatracker.ietf.org/doc/html/rfc7519#section-4.1 namely `exp`,
// `iat`, `nbf`, `iss` and `aud`.
type Claims interface {
	GetExpiryAt() *NumericDate
	GetIssuedAt() *NumericDate
	GetNotBefore() *NumericDate
	GetIssuer() string
	GetAudience() ClaimStrings
}

// RegisteredClaims are a structured version of the JWT Claims Set,
// restricted to Registered Claim Names, as referenced at
// https://datatracker.ietf.org/doc/html/rfc7519#section-4.1
//
// This type can be used on its own, but then additional private and
// public claims embedded in the JWT will not be parsed. The typical use-case
// therefore is to embedded this in a user-defined claim type.
//
// See examples for how to use this with your own claim types.
type RegisteredClaims struct {
	// the `iss` (Issuer) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.1
	Issuer string `json:"iss,omitempty"`

	// the `sub` (Subject) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.2
	Subject string `json:"sub,omitempty"`

	// the `aud` (Audience) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.3
	Audience ClaimStrings `json:"aud,omitempty"`

	// the `exp` (Expiration Time) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.4
	ExpiresAt *NumericDate `json:"exp,omitempty"`

	// the `nbf` (Not Before) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.5
	NotBefore *NumericDate `json:"nbf,omitempty"`

	// the `iat` (Issued At) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.6
	IssuedAt *NumericDate `json:"iat,omitempty"`

	// the `jti` (JWT ID) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.7
	ID string `json:"jti,omitempty"`
}

// GetExpiryAt implements the Claims interface.
func (c RegisteredClaims) GetExpiryAt() *NumericDate {
	return c.ExpiresAt
}

// GetNotBefore implements the Claims interface.
func (c RegisteredClaims) GetNotBefore() *NumericDate {
	return c.NotBefore
}

// GetIssuedAt implements the Claims interface.
func (c RegisteredClaims) GetIssuedAt() *NumericDate {
	return c.IssuedAt
}

// GetAudience implements the Claims interface.
func (c RegisteredClaims) GetAudience() ClaimStrings {
	return c.Audience
}

// GetIssuer implements the Claims interface.
func (c RegisteredClaims) GetIssuer() string {
	return c.Issuer
}