Merge pull request mouredev#7165 from hozlucas28/Solution-44-Go

mouredev#44 - Go

Author: kontroldev

Roadmap/44 - CUENTA ATRÁS MOUREDEV PRO/go/hozlucas28.go

@@ -0,0 +1,144 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"sync"
+	"time"
+)
+
+/* -------------------------------------------------------------------------- */
+/*                                   STRUCTS                                  */
+/* -------------------------------------------------------------------------- */
+
+type ITimer interface {
+	GetEndDate() *time.Time
+	TimerEnded() bool
+	UpdateTimer(from time.Time, to time.Time)
+	ToString() string
+}
+
+type timer struct {
+	Days    int64
+	Hours   int64
+	Minutes int64
+	Seconds int64
+
+	endDate time.Time
+	_       struct{}
+}
+
+func NewTimer(from time.Time, to time.Time) ITimer {
+	var timer timer = timer{endDate: to}
+
+	var unixStartDate int64 = from.Unix()
+	var unixEndDate int64 = to.Unix()
+
+	var remainingTime int64 = unixEndDate - unixStartDate
+	if remainingTime <= 0 {
+		return &timer
+	}
+
+	timer.Days = remainingTime / 86400
+	remainingTime -= timer.Days * 86400
+
+	timer.Hours = remainingTime / 3600
+	remainingTime -= timer.Hours * 3600
+
+	timer.Minutes = remainingTime / 60
+	remainingTime -= timer.Minutes * 60
+
+	timer.Seconds = remainingTime
+
+	return &timer
+}
+
+func (timer *timer) GetEndDate() *time.Time {
+	return &timer.endDate
+}
+
+func (timer *timer) TimerEnded() bool {
+	return timer.Days == 0 && timer.Hours == 0 && timer.Minutes == 0 && timer.Seconds == 0
+}
+
+func (timer *timer) UpdateTimer(from time.Time, to time.Time) {
+	timer.endDate = to
+
+	var unixStartDate int64 = from.Unix()
+	var unixEndDate int64 = to.Unix()
+
+	var remainingTime int64 = unixEndDate - unixStartDate
+	if remainingTime <= 0 {
+		timer.Days = 0
+		timer.Hours = 0
+		timer.Minutes = 0
+		timer.Seconds = 0
+		return
+	}
+
+	timer.Days = remainingTime / 86400
+	remainingTime -= timer.Days * 86400
+
+	timer.Hours = remainingTime / 3600
+	remainingTime -= timer.Hours * 3600
+
+	timer.Minutes = remainingTime / 60
+	remainingTime -= timer.Minutes * 60
+
+	timer.Seconds = remainingTime
+}
+
+func (timer *timer) ToString() string {
+	return fmt.Sprintf(
+		"[ %06d days | %02d hours | %02d minutes | %02d seconds ]",
+		timer.Days,
+		timer.Hours,
+		timer.Minutes,
+		timer.Seconds,
+	)
+}
+
+/* -------------------------------------------------------------------------- */
+/*                                    MAIN                                    */
+/* -------------------------------------------------------------------------- */
+
+func main() {
+	var wg sync.WaitGroup
+
+	wg.Add(1)
+
+	go func() {
+		var startDate time.Time = time.Now()
+		var endDate time.Time = time.Date(2024, time.December, 25, 0, 0, 0, 0, time.Local)
+		var timer ITimer = NewTimer(startDate, endDate)
+
+		var command = exec.Command("clear")
+		command.Stdout = os.Stdout
+		command.Run()
+
+		fmt.Printf(
+			"> Time remaining for %s: %s.\n", endDate, timer.ToString(),
+		)
+
+		for !timer.TimerEnded() {
+			time.Sleep(time.Second)
+
+			startDate = time.Now()
+			timer.UpdateTimer(startDate, *timer.GetEndDate())
+
+			command = exec.Command("clear")
+			command.Stdout = os.Stdout
+			command.Run()
+
+			fmt.Printf(
+				"> Time remaining for %s: %s.\n", endDate.Local().UTC(), timer.ToString(),
+			)
+		}
+
+		fmt.Println("\n> The day has come!")
+		wg.Done()
+	}()
+
+	wg.Wait()
+}