// -*- go -*-
//
// Copyright (c) 2021-2024 Markku Rossi
//
// All rights reserved.
//

package binary

// GetUint gets a MSB-encoded unsigned integer from the argument
// buffer. The size of the result number is determined by the length
// of the input buffer.
func GetUint(d []byte) uint {
	resultType := make(uint, len(d)*8)

	var result resultType
	for i := 0; i < len(d); i++ {
		result <<= 8
		result |= resultType(d[i])
	}
	return result
}

// PutUint puts the unsigned integer v to the buffer d starting from
// the offset offset in MSB-order. The number of bytes encoded is
// determined by the size of the input value v.
func PutUint(d []byte, offset int, v uint) []byte {
	bytes := size(v) / 8

	for i := 0; i < bytes; i++ {
		d[offset+bytes-1-i] = byte(v & 0xff)
		v >>= 8
	}
	return d
}

// GetUint32 gets a MSB-encoded uint32 value from the argument buffer.
func GetUint32(d []byte) uint32 {
	return uint32(d[0])<<24 | uint32(d[1])<<16 | uint32(d[2])<<8 | uint32(d[3])
}

// PutUint32 puts the uint32 value v to the buffer d starting from the
// offset offset in MSB-order.
func PutUint32(d []byte, offset int, v uint32) []byte {
	d[offset+0] = byte(v >> 24)
	d[offset+1] = byte(v >> 16)
	d[offset+2] = byte(v >> 8)
	d[offset+3] = byte(v)
	return d
}

// GetUint32 gets a LSB-encoded uint32 value from the argument buffer.
func GetUint32LSB(d []byte) uint32 {
	return uint32(d[0]) | uint32(d[1])<<8 | uint32(d[2])<<16 | uint32(d[3])<<24
}

// GetUint64 gets a MSB-encoded uint64 value from the argument buffer.
func GetUint64(d []byte) uint64 {
	return uint64(d[0])<<56 | uint64(d[1])<<48 |
		uint64(d[2])<<40 | uint64(d[3])<<32 |
		uint64(d[4])<<24 | uint64(d[5])<<16 |
		uint64(d[6])<<8 | uint64(d[7])
}

// PutUint64 puts the uint64 value v to the buffer d starting from the
// offset offset in MSB-order.
func PutUint64(d []byte, offset int, v uint64) []byte {
	d[offset+0] = byte(v >> 56)
	d[offset+1] = byte(v >> 48)
	d[offset+2] = byte(v >> 40)
	d[offset+3] = byte(v >> 32)
	d[offset+4] = byte(v >> 24)
	d[offset+5] = byte(v >> 16)
	d[offset+6] = byte(v >> 8)
	d[offset+7] = byte(v)
	return d
}

// GetUint64LSB gets a LSB-encoded uint64 value from the argument buffer.
func GetUint64LSB(d []byte) uint64 {
	return uint64(d[0]) | uint64(d[1])<<8 |
		uint64(d[2])<<16 | uint64(d[3])<<24 |
		uint64(d[4])<<32 | uint64(d[5])<<40 |
		uint64(d[6])<<48 | uint64(d[7])<<56
}