package cmd

import (
	"fmt"
	"log"
	"math"
	"time"

	"github.com/spf13/cobra"

	"github.com/nsfisis/term-clock/internal/term"
)

func drawTimer(scr *term.Screen, leftTime time.Duration, bgStyle, fgStyle term.Style) {
	if leftTime <= 0 {
		if int(math.Abs(leftTime.Seconds()))%2 == 0 {
			bgStyle, fgStyle = fgStyle, bgStyle
		}
		leftTime = 0
	}

	// Clear the entire screen.
	scr.Clear(bgStyle)

	squareW, squareH, xOffset, yOffset := calcSquareSize(scr)

	// Minute
	minute := int(leftTime.Minutes())
	term.DrawNumber(scr, minute/10, xOffset+squareW*0, yOffset, squareW, squareH, fgStyle)
	term.DrawNumber(scr, minute%10, xOffset+squareW*4, yOffset, squareW, squareH, fgStyle)

	// Colon
	term.DrawSquare(scr, xOffset+squareW*8, yOffset+squareH*1, squareW, squareH, fgStyle)
	term.DrawSquare(scr, xOffset+squareW*8, yOffset+squareH*3, squareW, squareH, fgStyle)

	// Second
	second := int(leftTime.Seconds()) % 60
	term.DrawNumber(scr, second/10, xOffset+squareW*10, yOffset, squareW, squareH, fgStyle)
	term.DrawNumber(scr, second%10, xOffset+squareW*14, yOffset, squareW, squareH, fgStyle)
}

func cmdTimer(cmd *cobra.Command, args []string) {
	timerTime, err := time.ParseDuration(args[0])
	if err != nil {
		log.Fatalf("%+v", err)
	}

	if timerTime.Minutes() > 99 {
		fmt.Println("Duration over 99 minutes is not supported.")
		return
	}

	scr, err := term.NewScreen()
	if err != nil {
		log.Fatalf("%+v", err)
	}
	defer scr.Close()

	startTime := time.Now()

	drawTimer(scr, (timerTime - time.Now().Sub(startTime)).Round(time.Second), term.BgStyle, term.FgStyle)

	scr.OnResize(func() bool {
		drawTimer(scr, (timerTime - time.Now().Sub(startTime)).Round(time.Second), term.BgStyle, term.FgStyle)
		return false
	})
	go scr.DoEventLoop()

	t := time.NewTicker(1 * time.Second)
	defer t.Stop()

	for {
		select {
		case <-scr.QuitC:
			return
		case now := <-t.C:
			drawTimer(scr, (timerTime - now.Sub(startTime)).Round(time.Second), term.BgStyle, term.FgStyle)
			scr.Show()
		}
	}
}

var timerCmd = &cobra.Command{
	Use:   "timer",
	Short: "Timer mode",
	Run:   cmdTimer,
	Args:  cobra.ExactArgs(1),
}