66 lines
1.9 KiB
V
66 lines
1.9 KiB
V
|
module base58
|
||
|
|
||
|
// alphabets is a map of common base58 alphabets
|
||
|
pub const alphabets = init_alphabets()
|
||
|
|
||
|
// init_alphabet instantiates the preconfigured `Alphabet`s and returns them as `map[string]Alphabet`.
|
||
|
// This is a temporary function. Setting const alphabets to the value returned in this function
|
||
|
// causes a C error right now.
|
||
|
fn init_alphabets() map[string]Alphabet {
|
||
|
return {
|
||
|
'btc': new_alphabet('123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz') or {
|
||
|
panic(@MOD + '.' + @FN + ': this should never happen')
|
||
|
}
|
||
|
'flickr': new_alphabet('123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ') or {
|
||
|
panic(@MOD + '.' + @FN + ': this should never happen')
|
||
|
}
|
||
|
'ripple': new_alphabet('rpshnaf39wBUDNEGHJKLM4PQRST7VWXYZ2bcdeCg65jkm8oFqi1tuvAxyz') or {
|
||
|
panic(@MOD + '.' + @FN + ': this should never happen')
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// Alphabet is the series of characters that an input
|
||
|
// will be encoded to and a decode table.
|
||
|
struct Alphabet {
|
||
|
mut:
|
||
|
decode []i8 = []i8{len: 128, init: -1}
|
||
|
encode []byte = []byte{len: 58}
|
||
|
}
|
||
|
|
||
|
// str returns an Alphabet encode table byte array as a string
|
||
|
pub fn (alphabet Alphabet) str() string {
|
||
|
// i guess i had a brain fart here. Why would I actually use this code?!
|
||
|
// mut str := []byte{}
|
||
|
// for entry in alphabet.encode {
|
||
|
// str << entry
|
||
|
// }
|
||
|
// return str.bytestr()
|
||
|
return alphabet.encode.bytestr()
|
||
|
}
|
||
|
|
||
|
// new_alphabet instantiates an Alphabet object based on
|
||
|
// the provided characters
|
||
|
pub fn new_alphabet(str string) ?Alphabet {
|
||
|
if str.len != 58 {
|
||
|
return error(@MOD + '.' + @FN + ': string must be 58 characters in length')
|
||
|
}
|
||
|
|
||
|
mut ret := Alphabet{}
|
||
|
copy(ret.encode, str.bytes())
|
||
|
|
||
|
mut distinct := 0
|
||
|
for i, b in ret.encode {
|
||
|
if ret.decode[b] == -1 {
|
||
|
distinct++
|
||
|
}
|
||
|
ret.decode[b] = i8(i)
|
||
|
}
|
||
|
|
||
|
if distinct != 58 {
|
||
|
return error(@MOD + '.' + @FN + ': string must not contain repeating characters')
|
||
|
}
|
||
|
|
||
|
return ret
|
||
|
}
|