package widgets

import (
	"ArinDash/util"
	"context"
	"fmt"
	"time"

	"github.com/mum4k/termdash/cell"
	"github.com/mum4k/termdash/terminal/terminalapi"
	"github.com/mum4k/termdash/widgetapi"
	"github.com/mum4k/termdash/widgets/text"
)

type CalendarOptions struct {
}

func Calendar() CalendarOptions {
	widgetOptions["CalendarOptions"] = createCalendar
	return CalendarOptions{}
}

func createCalendar(ctx context.Context, _ terminalapi.Terminal, _ interface{}) widgetapi.Widget {
	widget := util.PanicOnErrorWithResult(text.New())

	go util.Periodic(ctx, 1*time.Hour, func() error {

		widget.Reset()
		if err := widget.Write("┌────────────────────┐\n", text.WriteCellOpts(cell.FgColor(cell.ColorWhite))); err != nil {
			return err
		}
		if err := widget.Write(fmt.Sprintf("|%-20s|\n", time.Now().Format("January 2006")), text.WriteCellOpts(cell.FgColor(cell.ColorWhite))); err != nil {
			return err
		}
		if err := widget.Write("├──┬──┬──┬──┬──┬──┬──┤\n", text.WriteCellOpts(cell.FgColor(cell.ColorWhite))); err != nil {
			return err
		}
		if err := createRow(widget, "Mo", "Tu", "We", "Th", "Fr", "Sa", "Su"); err != nil {
			return err
		}
		if err := createTableForMonth(widget); err != nil {
			return err
		}
		if err := createLowerBorder(widget); err != nil {
			return err
		}
		return nil
	})

	return widget
}

func createTableForMonth(widget *text.Text) error {
	table := make([]int, 0)
	now := time.Now()
	firstMonthday := time.Date(now.Year(), now.Month(), 1, 0, 0, 0, 0, time.UTC)
	for range (firstMonthday.Weekday() + 6) % 7 {
		table = append(table, 0)
	}

	for {
		day := firstMonthday.Day()
		table = append(table, day)
		firstMonthday = firstMonthday.AddDate(0, 0, 1)
		if firstMonthday.Month() != now.Month() {
			break
		}
	}
	remainingDays := 8 - len(table)/7
	for range remainingDays {
		table = append(table, 0)
	}

	for index, field := range table {
		if index%7 == 0 {
			if err := createMiddle(widget); err != nil {
				return err
			}
		}
		var str string
		if err := widget.Write("│"); err != nil {
			return err
		}
		if field == 0 {
			str = fmt.Sprintf("  ")
		} else {
			str = fmt.Sprintf("%2d", field)
		}
		var color text.WriteOption
		if field == now.Day() {
			color = text.WriteCellOpts(cell.FgColor(cell.ColorBlack), cell.BgColor(cell.ColorWhite), cell.Bold())
		} else {
			color = text.WriteCellOpts(cell.FgColor(cell.ColorWhite), cell.BgColor(cell.ColorDefault))
		}
		if err := widget.Write(str, color); err != nil {
			return err
		}
		if index%7 == 6 {
			if err := widget.Write("│\n"); err != nil {
				return err
			}
		}
	}
	return nil
}

func createLowerBorder(widget *text.Text) error {
	result := "└─"
	for range 6 {
		result += "─┴─"
	}
	result += "─┘\n"
	if err := widget.Write(result, text.WriteCellOpts(cell.FgColor(cell.ColorWhite))); err != nil {
		return err
	}
	return nil
}

func createMiddle(widget *text.Text) error {
	result := "├─"
	for range 6 {
		result += "─┼─"
	}
	result += "─┤\n"
	if err := widget.Write(result, text.WriteCellOpts(cell.FgColor(cell.ColorWhite))); err != nil {
		return err
	}
	return nil
}

func createRow(widget *text.Text, cells ...string) error {
	result := "│"
	for index, field := range cells {
		result += fmt.Sprintf("%2s", field)
		if index < len(cells)-1 {
			result += "│"
		} else {
			result += "│\n"
		}
	}
	if err := widget.Write(result, text.WriteCellOpts(cell.FgColor(cell.ColorWhite))); err != nil {
		return err
	}
	return nil
}