package main

import (
	"fmt"
	"log"
	"time"

	"github.com/jroimartin/gocui"
)

type UIState struct {
	SelCalMonth time.Month
	SelCalDay   int
	SelCalYear  int
}

var uiState *UIState

func DoUIMode() {
	uiState = &UIState{
		SelCalMonth: time.Now().Month(),
		SelCalDay:   time.Now().Day(),
		SelCalYear:  time.Now().Year(),
	}
	g, err := gocui.NewGui(gocui.Output256)
	if err != nil {
		log.Panicln(err)
	}
	defer g.Close()
	g.Cursor = true
	g.SetManagerFunc(uiLayout)

	// Set up some keybindings
	if err := g.SetKeybinding("", gocui.KeyCtrlC, gocui.ModNone, quit); err != nil {
		log.Panicln(err)
	}
	if err := g.SetKeybinding("", 'q', gocui.ModNone, quit); err != nil {
		log.Panicln(err)
	}

	// And now the main loop
	if err := g.MainLoop(); err != nil && err != gocui.ErrQuit {
		log.Panicln(err)
	}
}

func uiLayout(g *gocui.Gui) error {
	if v, err := g.SetView("cal_view", 0, 0, 20, 62); err != nil {
		if err != gocui.ErrUnknownView {
			return err
		}
		v.SelBgColor = gocui.ColorGreen
		v.SelFgColor = gocui.ColorBlack

		drawCalendar(g, v)
		if _, err = g.SetCurrentView("cal_view"); err != nil {
			return err
		}
	}
	return nil
}

func updateUiViews(g *gocui.Gui) error {
	for _, v := range g.Views() {
		v.Clear()
		switch v.Name() {
		case "cal_view":
			if err := drawCalendar(g, v); err != nil {
				return err
			}
		}
	}
	return nil
}

func drawCalendar(g *gocui.Gui, v *gocui.View) error {
	// Print the 'Today' String
	fmt.Fprintln(v, "<", uiState.SelCalMonth.String()[:3], uiState.SelCalDay, ",", uiState.SelCalYear, ">")
	// Find the first of the month's week day
	for wrkDay := 1; wrkDay <= 31; wrkDay++ {
		wrkCalString := fmt.Sprintf("%04d%02d%02d", uiState.SelCalYear, uiState.SelCalMonth, wrkDay)
		wrkTime, _ := time.Parse("20060102", wrkCalString)
		fmt.Fprintf(v, "%04d%02d%02d\n", wrkTime.Year(), wrkTime.Month(), wrkTime.Day())
		fmt.Fprintln(v, wrkTime.Weekday())
		if wrkDay == 1 {
			// For the first day, we need to space it in wrkTime.Weekday() spaces
			for i := 0; i < int(wrkTime.Weekday()); i++ {

			}
		}
	}

	return nil
}