Initial QSfera import

Server/vendor/github.com/gookit/goutil/strutil/convbase.go

@@ -0,0 +1,108 @@
+package strutil
+
+import (
+	"math/big"
+	"strconv"
+	"strings"
+
+	"github.com/gookit/goutil/x/basefn"
+)
+
+//
+// -------------------- convert base --------------------
+//
+
+const (
+	Base10Chars = "0123456789"
+	Base16Chars = "0123456789abcdef"
+	Base32Chars = "0123456789abcdefghjkmnpqrstvwxyz"
+	Base36Chars = "0123456789abcdefghijklmnopqrstuvwxyz"
+	Base48Chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKL"
+	Base62Chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+	Base64Chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ+/"
+)
+
+// Base10Conv convert base10 string to new base string.
+func Base10Conv(src string, to int) string { return BaseConv(src, 10, to) }
+
+// BaseConv convert base string by from and to base.
+//
+// Note: from and to base must be in [2, 64]
+//
+// Usage:
+//
+//	BaseConv("123", 10, 16) // Output: "7b"
+//	BaseConv("7b", 16, 10) // Output: "123"
+func BaseConv(src string, from, to int) string {
+	if from > 64 || from < 2 {
+		from = 10
+	}
+	if to > 64 || to < 2 {
+		to = 16
+	}
+	return BaseConvByTpl(src, Base64Chars[:from], Base64Chars[:to])
+}
+
+// BaseConvInt convert base int to new base string.
+//
+// Usage:
+//
+//	BaseConv(123, 16) // Output: "7b"
+func BaseConvInt(src uint64, toBase int) string {
+	if toBase > 64 || toBase < 2 {
+		toBase = 16
+	}
+
+	// bigInt 支持 2-62 进制转换处理 TODO
+	if toBase <= 36 {
+		return strconv.FormatUint(src, toBase)
+	}
+	if toBase <= 62 {
+		bigInt := new(big.Int).SetUint64(src)
+		return bigInt.Text(toBase)
+	}
+
+	return BaseConvIntByTpl(src, Base64Chars[:toBase])
+}
+
+// BaseConvByTpl convert base string by template.
+//
+// Usage:
+//
+//	BaseConvert("123", Base62Chars, Base16Chars) // Output: "1e"
+//	BaseConvert("1e", Base16Chars, Base62Chars) // Output: "123"
+func BaseConvByTpl(src string, fromBase, toBase string) string {
+	if fromBase == toBase {
+		return src
+	}
+
+	// convert to base 10
+	var dec uint64
+	if fromBase == Base10Chars {
+		var err error
+		dec, err = strconv.ParseUint(src, 10, 0)
+		if err != nil {
+			basefn.Panicf("input is not a valid decimal number: %s(%v)", src, err)
+		}
+	} else {
+		fLen := uint64(len(fromBase))
+		for _, c := range src {
+			dec = dec*fLen + uint64(strings.IndexRune(fromBase, c))
+		}
+	}
+
+	// convert to new base
+	return BaseConvIntByTpl(dec, toBase)
+}
+
+// BaseConvIntByTpl convert base int to new base string.
+func BaseConvIntByTpl(dec uint64, toBase string) string {
+	// convert to new base
+	var res string
+	toLen := uint64(len(toBase))
+	for dec > 0 {
+		res = string(toBase[dec%toLen]) + res
+		dec /= toLen
+	}
+	return res
+}