package btcwire

import "errors"

// Sentinel errors returned by this package. Every returned error wraps one of
// these (or io.ErrUnexpectedEOF for truncated input) together with context
// describing what was being decoded, so callers should match them with
// errors.Is rather than comparing strings.
var (
	// ErrBadMagic is returned when a frame header carries a network magic
	// other than the one the caller expects.
	ErrBadMagic = errors.New("btcwire: unexpected network magic")

	// ErrBadChecksum is returned when the checksum in a frame header does not
	// match the checksum of the payload that followed it.
	ErrBadChecksum = errors.New("btcwire: payload checksum mismatch")

	// ErrPayloadTooLarge is returned when a payload exceeds MaxPayload, both
	// when encoding one and when a frame header declares one.
	ErrPayloadTooLarge = errors.New("btcwire: payload exceeds maximum size")

	// ErrInvalidCommand is returned when a command is empty, longer than 12
	// bytes, or contains characters that are not printable ASCII.
	ErrInvalidCommand = errors.New("btcwire: invalid command")

	// ErrInvalidPayload is returned when a payload is malformed: a message
	// that must be empty is not, a fixed-size message has the wrong size, a
	// headers entry declares transactions, and so on.
	ErrInvalidPayload = errors.New("btcwire: invalid payload")

	// ErrInvalidLength is returned when a length or limit is negative or
	// otherwise unusable.
	ErrInvalidLength = errors.New("btcwire: invalid length")

	// ErrVarBytesTooLarge is returned when a variable length byte string is
	// longer than the caller supplied limit.
	ErrVarBytesTooLarge = errors.New("btcwire: variable length field exceeds limit")

	// ErrNonCanonicalCompactSize is returned when a compact size integer is
	// not minimally encoded.
	ErrNonCanonicalCompactSize = errors.New("btcwire: non-canonical compact size")

	// ErrTooManyItems is returned when a vector in a message declares more
	// elements than the protocol allows for that message.
	ErrTooManyItems = errors.New("btcwire: item count exceeds limit")

	// ErrInvalidAddress is returned when an IP address string cannot be
	// parsed.
	ErrInvalidAddress = errors.New("btcwire: invalid IP address")

	// ErrTargetNegative is returned for a compact target whose sign bit is
	// set.
	ErrTargetNegative = errors.New("btcwire: negative target")

	// ErrTargetOverflow is returned for a compact target that does not fit in
	// 256 bits.
	ErrTargetOverflow = errors.New("btcwire: target overflows 256 bits")
)