package main

import (
	"fmt"
	"strings"
	"time"

	"github.com/samber/lo"
	tele "gopkg.in/telebot.v3"

	"git.gensokyo.cafe/kkyy/tgbot_misaka_5882f7/stats"
)

var (
	trafficMenu                      = &tele.ReplyMarkup{}
	trafficBtnDays, trafficBtnMonths tele.Btn
)

func init() {
	trafficBtnDays = trafficMenu.Data("🌝 Days", "btn_traffic_days")
	trafficBtnMonths = trafficMenu.Data("🗓️ Months", "btn_traffic_months")

	trafficMenu.Inline(trafficMenu.Row(trafficBtnDays, trafficBtnMonths))
}

func handleTrafficCmd(c tele.Context) error {
	dailyTraffic, err := stats.VnstatDailyTraffic(config.WatchedInterface)
	if err != nil {
		_ = c.Reply(stickerFromID(stickerPanic), tele.Silent)
		return err
	}
	monthlyTraffic, err := stats.VnstatMonthlyTraffic(config.WatchedInterface)
	if err != nil {
		_ = c.Reply(stickerFromID(stickerPanic), tele.Silent)
		return err
	}

	var responseParts = []string{"*Traffic Usage Summaries*\n"}
	// Yesterday's traffic if present
	if len(dailyTraffic) > 1 {
		row := dailyTraffic[len(dailyTraffic)-2]
		day := fmt.Sprintf("%d-%02d-%02d", row.Date.Year, row.Date.Month, row.Date.Day)
		responseParts = append(responseParts, fmt.Sprintf("Yesterday (%s):` %s`", day, fmtTraffic(row)))
	}
	// Today's traffic if present
	if len(dailyTraffic) > 0 {
		row := dailyTraffic[len(dailyTraffic)-1]
		responseParts = append(responseParts, fmt.Sprintf("Today so far:` %s`\n", fmtTraffic(row)))
	}

	// Last month's traffic, if present
	if len(monthlyTraffic) > 1 {
		row := monthlyTraffic[len(monthlyTraffic)-2]
		month := fmt.Sprintf("%d-%02d", row.Date.Year, row.Date.Month)
		responseParts = append(responseParts, fmt.Sprintf("Last month (%s):` %s`", month, fmtTraffic(row)))
	}
	// This month's traffic, if present
	if len(monthlyTraffic) > 0 {
		row := monthlyTraffic[len(monthlyTraffic)-1]
		responseParts = append(responseParts, fmt.Sprintf("This month so far:` %s`", fmtTraffic(row)))
		responseParts = append(responseParts, drawBarForTrafficRecord(row))
	}

	var respText string
	if len(responseParts) == 1 {
		respText = "No traffic data available."
	} else {
		respText = strings.Join(responseParts, "\n")
	}

	return c.Reply(respText, &tele.SendOptions{ParseMode: tele.ModeMarkdown}, tele.Silent, trafficMenu)
}

func fmtTraffic(r stats.VnstatTrafficRecord) string {
	effective := lo.Max([]uint64{r.Rx, r.Tx})
	return fmt.Sprintf("%.2f GiB", float64(effective)/1024/1024/1024)
}

func drawBarForTrafficRecord(r stats.VnstatTrafficRecord) string {
	effective := lo.Max([]uint64{r.Rx, r.Tx})
	max := config.MonthlyTrafficLimitGiB
	ratio := float64(effective) / 1024 / 1024 / 1024 / float64(max)
	return fmt.Sprintf("`%s %2.0f%%`", drawBar(ratio, 16), ratio*100)
}

func handleTrafficBtnDays(c tele.Context) error {
	dailyTraffic, err := stats.VnstatDailyTraffic(config.WatchedInterface)
	if err != nil {
		_ = c.Reply(stickerFromID(stickerPanic), tele.Silent)
		return err
	}

	var responseParts = []string{
		"*Traffic usage of recent days*",
		fmt.Sprintf("_updated at %s_\n", time.Now().Format("15:04:05")),
	}

	offset := lo.Max([]int{0, len(dailyTraffic) - 14})
	for _, tr := range dailyTraffic[offset:] {
		day := time.Date(int(tr.Date.Year), time.Month(tr.Date.Month), int(tr.Date.Day), 0, 0, 0, 0, time.Local)
		dayStr := fmt.Sprintf("%s (%s)", day.Format("01-02"), day.Weekday().String()[0:3])

		responseParts = append(responseParts, fmt.Sprintf("`%s: %10s`", dayStr, fmtTraffic(tr)))
	}

	var respText string
	if len(responseParts) == 1 {
		respText = "No daily traffic data available."
	} else {
		respText = strings.Join(responseParts, "\n")
	}
	return c.Edit(respText, &tele.SendOptions{ParseMode: tele.ModeMarkdown}, trafficMenu)
}

func handleTrafficBtnMonths(c tele.Context) error {
	monthlyTraffic, err := stats.VnstatMonthlyTraffic(config.WatchedInterface)
	if err != nil {
		_ = c.Reply(stickerFromID(stickerPanic), tele.Silent)
		return err
	}

	var responseParts = []string{
		"*Traffic usage of recent months*",
		fmt.Sprintf("_updated at %s_\n", time.Now().Format("15:04:05")),
	}
	for _, tr := range monthlyTraffic {
		responseParts = append(
			responseParts,
			fmt.Sprintf("`%d-%02d: %10s`", tr.Date.Year, tr.Date.Month, fmtTraffic(tr)),
		)
	}

	var respText string
	if len(responseParts) == 1 {
		respText = "No monthly traffic data available."
	} else {
		respText = strings.Join(responseParts, "\n")
	}
	return c.Edit(respText, &tele.SendOptions{ParseMode: tele.ModeMarkdown}, trafficMenu)
}