package main

import (
	"flag"
	"fmt"
	"os"
	"strings"
	"time"
)

const ANSI_RED = "\u001b[31m"
const ANSI_GREEN = "\u001b[32m"
const ANSI_RESET = "\u001b[0m"

// Replace occurences of repl with their uppercase in str
func replace(str string, repl []string, prefix string, suffix string) string {
	ret := str
	for _, r := range repl {
		rx := fmt.Sprintf("%s%s%s", prefix, strings.ToUpper(r), suffix)
		ret = strings.ReplaceAll(ret, r, rx)
	}
	return ret
}

func woordklok(tsp time.Time, color bool) string {
	// minutes part
	klok1 := "hetknisadvzvijftiengkwartbovervoormhalf"
	// hours
	klok2 := "yachtweezesdrielftienxzevenegenviertwaalfeenvijfuur"

	mm := tsp.Minute()
	hh := tsp.Hour() % 12

	// get the matching text
	m := "het is "
	if mm >= 55 {
		m += "vijf voor"
	} else if mm >= 50 {
		m += "tien voor"
	} else if mm >= 45 {
		m += "kwart voor"
	} else if mm >= 40 {
		m += "tien over half"
	} else if mm >= 35 {
		m += "vijf over half"
	} else if mm >= 30 {
		m += "half"
	} else if mm >= 25 {
		m += "vijf voor half"
	} else if mm >= 20 {
		m += "tien voor half"
		hh++
	} else if mm >= 15 {
		m += "kwart over"
	} else if mm >= 10 {
		m += "tien over"
	} else if mm >= 5 {
		m += "vijf over"
	} else {
		m += " uur"
	}

	hours := []string{
		"twaalf",
		"een",
		"twee",
		"drie",
		"vier",
		"vijf",
		"zes",
		"zeven",
		"acht",
		"negen",
		"tien",
		"elf",
	}
	hour := hours[hh] + " uur"

	ret := ""

	// and replace the matching text with the uppercase
	prefix := ""
	suffix := ""
	if color {
		// Add color definitions
		prefix = ANSI_GREEN
		suffix = ANSI_RED
		ret = ANSI_RED
	}
	ret += fmt.Sprintf("%s%s", replace(klok1, strings.Split(m, " "), prefix, suffix), replace(klok2, strings.Split(hour, " "), prefix, suffix))
	if color {
		ret += ANSI_RESET
	}
	return ret
}

func IsTTY() bool {
	if fileInfo, _ := os.Stdout.Stat(); (fileInfo.Mode() & os.ModeCharDevice) != 0 {
		return true
	} else {
		return false
	}
}

func main() {
	color := flag.Bool("c", false, "Always use colors")
	batch := flag.Bool("b", false, "Batch mode (no colors)")
	flag.Parse()

	colors := *color
	if !colors {
		colors = IsTTY()
	}
	if *batch {
		colors = false
	}

	woord := woordklok(time.Now(), colors)
	fmt.Println(woord)
}