kanzi

type ByteTransform interface {
	// Forward applies the function to the src and writes the result
	// to the destination. Returns number of bytes read, number of bytes
	// written and possibly an error.
	Forward(src, dst []byte) (uint, uint, error)

	// Inverse applies the reverse function to the src and writes the result
	// to the destination. Returns number of bytes read, number of bytes
	// written and possibly an error.
	Inverse(src, dst []byte) (uint, uint, error)

	// MaxEncodedLen returns the max size required for the encoding output buffer
	MaxEncodedLen(srcLen int) int
}

type EntropyDecoder interface {
	// Read decodes data from the bitstream and return it in the provided buffer.
	// Return the number of bytes read from the bitstream
	Read(block []byte) (int, error)

	// BitStream returns the underlying bitstream
	BitStream() InputBitStream

	// Dispose must be called before getting rid of the entropy decoder
	// Trying to decode after a call to dispose gives undefined behavior
	Dispose()
}

type EntropyEncoder interface {
	// Write encodes the data provided into the bitstream. Return the number of bytes
	// written to the bitstream
	Write(block []byte) (int, error)

	// BitStream returns the underlying bitstream
	BitStream() OutputBitStream

	// Dispose must be called before getting rid of the entropy encoder
	// Trying to encode after a call to dispose gives undefined behavior
	Dispose()
}

type Event struct {
	// contains filtered or unexported fields
}

type InputBitStream interface {
	// ReadBit returns the next bit in the bitstream. Panics if closed or EOS is reached.
	ReadBit() int

	// ReadBits reads 'length' (in [1..64]) bits from the bitstream.
	// Returns the bits read as an uint64.
	// Panics if closed or EOS is reached.
	ReadBits(length uint) uint64

	// ReadArray reads 'length' bits from the bitstream and put them in the byte slice.
	// Returns the number of bits read.
	// Panics if closed or EOS is reached.
	ReadArray(bits []byte, length uint) uint

	// Close makes the bitstream unavailable for further reads.
	Close() error

	// Read returns the number of bits read
	Read() uint64

	// HasMoreToRead returns false when the bitstream is closed or the EOS has been reached
	HasMoreToRead() (bool, error)
}

type IntTransform interface {
	// Forward applies the function to the source and writes the result
	// to the destination. Returns number of bytes read, number of bytes
	// written and possibly an error.
	Forward(src, dst []int) (uint, uint, error)

	// Inverse applies the reverse function to the source and writes the result
	// to the destination. Returns number of bytes read, number of bytes
	// written and possibly an error.
	Inverse(src, dst []int) (uint, uint, error)

	// MaxEncodedLen returns the max size required for the encoding output buffer
	// If the max size of the output buffer is not known, return -1
	MaxEncodedLen(srcLen int) int
}

type Listener interface {
	ProcessEvent(evt *Event)
}

type OutputBitStream interface {
	// WriteBit writes the least significant bit of the input integer.
	// Panics if closed or an IO error is received.
	WriteBit(bit int)

	// WriteBits writes the least significant bits of 'bits' to the bitstream.
	// Length is the number of bits to write (in [1..64]).
	// Returns the number of bits written.
	// Panics if closed or an IO error is received.
	WriteBits(bits uint64, length uint) uint

	// WriteArray writes bits out of the byte slice. Length is the number of bits.
	// Returns the number of bits written.
	// Panics if closed or an IO error is received.
	WriteArray(bits []byte, length uint) uint

	// Close makes the bitstream unavailable for further writes.
	Close() error

	// Written returns the number of bits written
	Written() uint64
}

type Predictor interface {
	// Update updates the internal probability model based on the observed bit
	Update(bit byte)

	// Get returns the value representing the probability of the next bit being 1
	// in the [0..4095] range.
	// E.G. 410 represents roughly a probability of 10% for 1
	Get() int
}