v4

.drone.yml

@@ -0,0 +1,10 @@
+---
+kind: pipeline
+type: docker
+name: default
+steps:
+- name: backend
+  image: golang
+  commands:
+  - go build
+  - go test

CHANGELOG

@@ -0,0 +1,12 @@
+v4.0.0, released 2025-01-06
+    * support both 32 and 64 bases
+    * added Convert command between bases
+
+v2.0.0, released 2024-09-20 
+    * move to base 62
+
+v1.0.2, released 2024-08-08 
+    * support negative values
+
+v1.0.1, released 2024-08-08 
+    * fix encoding to zero

README.md

@@ -1,3 +1,23 @@
 # abcex
 
-Computing system based on the number 36
+[![Build Status](https://drone.arns.lt/api/badges/zordsdavini/abcex/status.svg)](https://drone.arns.lt/zordsdavini/abcex)
+
+Computing system based on the number 62 or 36
+
+## Usage
+
+`Encode(int, int) -> string` - convert number into string based on given base.
+
+`Decode(string, int) -> int` - convert from encoded string into number based on given base.
+
+`Convert(string, int, int) -> string` - convert encoded string from one base to another.
+
+## History
+
+**Version 1** - based on 32: number and case insensitive letters
+
+**Version 2** - failed release
+
+**Version 3** - based on 62: number and case sensitive letters
+
+**Version 4** - support both versions, based on 62 and 32

abcex.go

@@ -1,53 +1,109 @@
 package abcex
 
-import "fmt"
-import "math"
+import (
+	"fmt"
+	"math"
+)
 
-var decToAbcex = map[int]string{
+var decToAbcex36 = map[int]string{
 	0: "0", 1: "1", 2: "2", 3: "3", 4: "4", 5: "5", 6: "6", 7: "7",
 	8: "8", 9: "9", 10: "a", 11: "b", 12: "c", 13: "d", 14: "e",
 	15: "f", 16: "g", 17: "h", 18: "i", 19: "j", 20: "k", 21: "l",
 	22: "m", 23: "n", 24: "o", 25: "p", 26: "q", 27: "r", 28: "s",
-	29: "t", 30: "u", 31: "v", 32: "w", 33: "x", 34: "y", 35: "z" }
-
-var abcexToDec = flipMap()
-
-func reverse(s string) string {
-    runes := []rune(s)
-    for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 {
-        runes[i], runes[j] = runes[j], runes[i]
-    }
-    return string(runes)
+	29: "t", 30: "u", 31: "v", 32: "w", 33: "x", 34: "y", 35: "z",
 }
 
-func flipMap() map[string]int {
-    flipped := make(map[string]int)
-    for i, val := range decToAbcex {
-        flipped[val] = i
-    }
-
-    return flipped
+var decToAbcex62 = map[int]string{
+	0: "0", 1: "1", 2: "2", 3: "3", 4: "4", 5: "5", 6: "6", 7: "7",
+	8: "8", 9: "9", 10: "A", 11: "B", 12: "C", 13: "D", 14: "E",
+	15: "F", 16: "G", 17: "H", 18: "I", 19: "J", 20: "K", 21: "L",
+	22: "M", 23: "N", 24: "O", 25: "P", 26: "Q", 27: "R", 28: "S",
+	29: "T", 30: "U", 31: "V", 32: "W", 33: "X", 34: "Y", 35: "Z",
+	36: "a", 37: "b", 38: "c", 39: "d", 40: "e", 41: "f", 42: "g",
+	43: "h", 44: "i", 45: "j", 46: "k", 47: "l", 48: "m", 49: "n",
+	50: "o", 51: "p", 52: "q", 53: "r", 54: "s", 55: "t", 56: "u",
+	57: "v", 58: "w", 59: "x", 60: "y", 61: "z",
 }
 
-func Encode(number int64) string{
-    result := ""
+var (
+	BASE36 int = 36
+	BASE62 int = 62
+)
 
-    for number > 0 {
-        result = fmt.Sprintf("%s%s", decToAbcex[int(number % 36)], result)
-        number /= 36
+func getDict(base int) map[int]string {
+	if base == 36 {
+		return decToAbcex36
+	} else if base == 62 {
+		return decToAbcex62
 	}
 
-    return result
+	panic("Invalid base")
 }
 
-func Decode(str string) int64 {
-    var result int64
+func reverse(s string) string {
+	runes := []rune(s)
+	for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 {
+		runes[i], runes[j] = runes[j], runes[i]
+	}
+	return string(runes)
+}
+
+func flipMap(dict map[int]string) map[string]int {
+	flipped := make(map[string]int)
+	for i, val := range dict {
+		flipped[val] = i
+	}
+
+	return flipped
+}
+
+func Encode(number int64, base int) string {
+	if number == 0 {
+		return "0"
+	}
+
+	result := ""
+	negative := false
+	if number < 0 {
+		number = number * (-1)
+		negative = true
+	}
+
+	for number > 0 {
+		result = fmt.Sprintf("%s%s", getDict(base)[int(number%int64(base))], result)
+		number /= int64(base)
+	}
+
+	if negative {
+		return "-" + result
+	}
+
+	return result
+}
+
+func Decode(str string, base int) int64 {
+	var result int64
 	result = 0
-    str = reverse(str)
+	abcexToDec := flipMap(getDict(base))
+	negative := false
+	if string(str[0]) == "-" {
+		negative = true
+		str = str[1:]
+	}
 
-    for i, c := range str {
-        result = int64(math.Pow(36, float64(i))) * int64(abcexToDec[string(c)]) + result
-    }
+	str = reverse(str)
 
-    return result
+	for i, c := range str {
+		result = int64(math.Pow(float64(base), float64(i)))*int64(abcexToDec[string(c)]) + result
+	}
+
+	if negative {
+		return result * (-1)
+	}
+
+	return result
+}
+
+func Convert(str string, fromBase int, toBase int) string {
+	return Encode(Decode(str, fromBase), toBase)
 }

abcex_test.go

@@ -1,14 +1,55 @@
 package abcex
 
-import "fmt"
-import "testing"
+import (
+	"testing"
+)
+
+func TestConvert(t *testing.T) {
+	if Convert("9ix", BASE36, BASE62) != "3D7" {
+		t.Fatal("Failed conversion")
+	}
+}
+
+func TestEncode36(t *testing.T) {
+	if Encode(12345, BASE36) != "9ix" {
+		t.Fatal("Failed encoding")
+	}
+}
+
+func TestDecode36(t *testing.T) {
+	if Decode("9ix", BASE36) != 12345 {
+		t.Fatal("Failed decoding")
+	}
+}
 
 func TestEncode(t *testing.T) {
-    fmt.Println(Encode(12345))
-    // Output: 9ix
+	if Encode(12345, BASE62) != "3D7" {
+		t.Fatal("Failed encoding")
+	}
 }
 
 func TestDecode(t *testing.T) {
-    fmt.Println(Decode("9ix"))
-    // Output: 12345
+	if Decode("3D7", BASE62) != 12345 {
+		t.Fatal("Failed decoding")
+	}
+}
+
+func TestZero(t *testing.T) {
+	if Encode(0, BASE62) != "0" {
+		t.Fatal("Failed zero encoding")
+	}
+
+	if Decode("0", BASE62) != 0 {
+		t.Fatal("Failed zero decoding")
+	}
+}
+
+func TestNegative(t *testing.T) {
+	if Encode(-20, BASE62) != "-K" {
+		t.Fatal("Failed negative encoding:", Encode(-20, BASE62))
+	}
+
+	if Decode("-ab", BASE62) != -2269 {
+		t.Fatal("Failed negative decoding", Decode("-ab", BASE62))
+	}
 }

go.mod

@@ -1,3 +1,3 @@
-module g.arns.lt/zordsdavini/abcex
+module g.arns.lt/zordsdavini/abcex/v4
 
 go 1.16