grokify/mogo

package password

import (
    "strings"

    "github.com/grokify/mogo/crypto/randutil"
    "github.com/grokify/mogo/encoding/basex"
    "github.com/grokify/mogo/type/stringsutil"
)

// Generate creates passwords using options selected in `GenerateOpts`.
func Generate(opts GenerateOpts) string {
    return randutil.RandString(opts.Alphabet(), opts.Length)
}

const (
    AlphabetSymbols   = "!@#$%&*?"
    AlphabetAmbiguous = "{}[]()/\\'\"`,;:.<>"
    AlphabetSimilar   = "iI1LoO0"
)

type GenerateOpts struct {
    Length        uint
    InclLower     bool
    InclUpper     bool
    InclNumbers   bool
    InclSymbols   bool
    InclAmbiguous bool
    ExclSimilar   bool
}

// Alphabet builds an alphabet that's useful for passwords.
func (opts GenerateOpts) Alphabet() string {
    var alphabet string
    if opts.InclLower {
        alphabet += strings.ToLower(basex.AlphabetBase26)
    }
    if opts.InclNumbers {
        alphabet += basex.AlphabetBase10
    }
    if opts.InclUpper {
        alphabet += strings.ToUpper(basex.AlphabetBase26)
    }
    if opts.InclSymbols {
        alphabet += AlphabetSymbols
    }
    if opts.InclAmbiguous {
        alphabet += AlphabetAmbiguous
    }
    if opts.ExclSimilar {
        alphabet = stringsutil.StripChars(alphabet, AlphabetSimilar)
    }
    return alphabet
}