Audible - Golang book reader as it prints the words it speaks (MacOS > say)

audible.go

package main

import (
	"flag"
	"fmt"
	"io/ioutil"
	"log"
	"os/exec"
	"runtime"
	"strings"
	"time"
)

var filename string
var voice string
var speachRate int

func main() {
	flag.StringVar(&filename, "book", "", "text file book")
	flag.StringVar(&voice, "voice", "Karen", "voice")
	flag.IntVar(&speachRate, "speachrate", 6, "speach rate * the words from the sentence")
	flag.Parse()

	if err := checkSpeechSupport(); err != nil {
		log.Fatal(err)
	}

	sentences := getBookContent(filename)
	sentenceDone := make(chan bool)

	fmt.Printf("- Reading book: %v\n\n", filename)

	for _, sentence := range sentences {
		sentence = sentence + "."
		go textReader(sentence, sentenceDone)
		speechReader(sentence)
		<-sentenceDone
	}

	fmt.Println("\n- Finished book.")
}

func checkSpeechSupport() error {
	switch runtime.GOOS {
	case "darwin":
		return nil
	default:
		return fmt.Errorf("No support for text-to-speech in OS %v", runtime.GOOS)
	}
}

func getBookContent(file string) []string {
	book, err := ioutil.ReadFile(file)
	if err != nil {
		log.Fatal(err)
	}

	allSentences := strings.TrimSuffix(string(book), "\n")
	sentences := strings.Split(allSentences, ".")
	return sentences
}

func speechReader(sentence string) {
	switch runtime.GOOS {
	case "darwin":
		exec.Command("say", "-v", voice, sentence).Run()
	default:
		log.Fatalf("No support for text-to-speech in OS %v", runtime.GOOS)
	}
}

func textReader(sentence string, sentenceDone chan bool) {
	words := strings.Split(sentence, " ")
	pausePerWord := len(words) * speachRate

	for _, w := range words {
		fmt.Printf("%v ", w)
		time.Sleep(time.Millisecond * time.Duration(pausePerWord))
	}

	fmt.Printf("\n")

	sentenceDone <- true
}

homer.txt

Tell me, Muse, of that man, so ready at need, who wandered
far and wide, after he had sacked the sacred citadel of
Troy, and many were the men whose towns he saw and whose
mind he learnt, yea, and many the woes he suffered in his
heart on the deep, striving to win his own life and the
return of his company. Nay, but even so he saved not his
company, though he desired it sore. For through the
blindness of their own hearts they perished, fools, who
devoured the oxen of Helios Hyperion: but the god took from
them their day of returning. Of these things, goddess,
daughter of Zeus, whencesoever thou hast heard thereof,
declare thou even unto us.

Now all the rest, as many as fled from sheer destruction,
were at home, and had escaped both war and sea, but
Odysseus only, craving for his wife and for his homeward
path, the lady nymph Calypso held, that fair goddess, in her
hollow caves, longing to have him for her lord. But when
now the year had come in the courses of the seasons,
wherein the gods had ordained that he should return home to
Ithaca, not even there was he quit of labours, not even
among his own; but all the gods had pity on him save
Poseidon, who raged continually against godlike Odysseus,
till he came to his own country. Howbeit Poseidon had now
departed for the distant Ethiopians, the Ethiopians that are
sundered in twain, the uttermost of men, abiding some where
Hyperion sinks and some where he rises. There he looked to
receive his hecatomb of bulls and rams, there he made merry
sitting at the feast, but the other gods were gathered in
the halls of Olympian Zeus. Then among them the father of
men and gods began to speak, for he bethought him in his
heart of noble Aegisthus, whom the son of Agamemnon,
far-famed Orestes, slew.