// Copyright (c) 2026 Charles KWON OhJun (charleskwonohjun@gmail.com)
// All rights reserved.

// Encoding/hashing functions using Go's standard library.
// HB_MD5, HB_SHA256, HB_BASE64ENCODE, HB_BASE64DECODE, HB_CRC32

package hbrtl

import (
	"crypto/md5"
	"crypto/sha256"
	"encoding/base64"
	"encoding/hex"
	"fmt"
	"five/hbrt"
	"hash/crc32"
)

// HB_MD5(cString) → cHexDigest (32 chars)
func HbMD5(t *hbrt.Thread) {
	t.Frame(1, 0)
	defer t.EndProc()
	s := t.Local(1).AsString()
	h := md5.Sum([]byte(s))
	t.RetString(hex.EncodeToString(h[:]))
}

// HB_SHA256(cString) → cHexDigest (64 chars)
func HbSHA256(t *hbrt.Thread) {
	t.Frame(1, 0)
	defer t.EndProc()
	s := t.Local(1).AsString()
	h := sha256.Sum256([]byte(s))
	t.RetString(hex.EncodeToString(h[:]))
}

// HB_BASE64ENCODE(cString [, nLineLen]) → cBase64
func HbBase64Encode(t *hbrt.Thread) {
	nParams := t.ParamCount()
	t.Frame(nParams, 0)
	defer t.EndProc()
	s := t.Local(1).AsString()
	t.RetString(base64.StdEncoding.EncodeToString([]byte(s)))
}

// HB_BASE64DECODE(cBase64) → cString
func HbBase64Decode(t *hbrt.Thread) {
	t.Frame(1, 0)
	defer t.EndProc()
	s := t.Local(1).AsString()
	data, err := base64.StdEncoding.DecodeString(s)
	if err != nil {
		t.RetString("")
		return
	}
	t.RetString(string(data))
}

// HB_CRC32(cString) → nCRC32
func HbCRC32(t *hbrt.Thread) {
	t.Frame(1, 0)
	defer t.EndProc()
	s := t.Local(1).AsString()
	crc := crc32.ChecksumIEEE([]byte(s))
	t.RetLong(int64(crc))
}

var _ = fmt.Sprintf // keep fmt import for future use