evalphobia/google-tts-go

package googletts

import (
    "errors"
    "strconv"
    "unicode/utf8"
)

// Option contains optional parameters for Google TTS API.
type Option struct {
    Client     string
    Encoding   string
    Lang       string
    Text       string
    TextLength int
    Token      string
    TTSSpeed   float64 // voice speed (0.0 - 1.0)
}

// Validate validates option parameters.
func (o Option) Validate() error {
    if o.Text == "" {
        return errors.New("`Option.Text` must not be empty")
    }
    return nil
}

func (o Option) getClient() string {
    if o.Client != "" {
        return o.Client
    }
    return "t"
}

func (o Option) getEncoding() string {
    if o.Encoding != "" {
        return o.Encoding
    }
    return "UTF-8"
}

func (o Option) getLang() string {
    if o.Lang != "" {
        return o.Lang
    }
    return "en"
}

func (o Option) getText() string {
    return o.Text
}

func (o Option) getTextLength() string {
    if o.TextLength > 0 {
        return strconv.Itoa(o.TextLength)
    }
    return strconv.Itoa(utf8.RuneCountInString(o.Text))
}

func (o Option) getToken() string {
    return o.Token
}

func (o Option) getTTSSpeed() string {
    if o.TTSSpeed > 0 {
        return strconv.FormatFloat(o.TTSSpeed, 'f', 3, 64)
    }
    return "1"
}