package app

import (
	"log"
	"os"
	"simple_ui/internal/components"
	"simple_ui/internal/ui"

	"gioui.org/app"
	"gioui.org/layout"
	"gioui.org/op"
	"gioui.org/unit"
	"gioui.org/widget"
	"gioui.org/widget/material"
	"golang.org/x/exp/shiny/materialdesign/icons"
)

func Run() {
	go runApp()
	app.Main()
}

func runApp() {
	w := &app.Window{}

	w.Option(
		app.Title("Simple UI"),
		app.Size(800, 600),
		app.MinSize(400, 300),
	)

	err := runWindowEvents(w)
	if err != nil {
		log.Fatal(err)
	}
	os.Exit(0)
}

func runWindowEvents(window *app.Window) error {
	theme := material.NewTheme()
	var ops op.Ops
	currentPage := HomePage

	navMenu := components.NewNavigationMenu(theme)

	homeIcon, err := widget.NewIcon(icons.ActionHome)
	if err != nil {
		log.Fatalf("failed to create home icon: %v", err)
	}
	aboutIcon, err := widget.NewIcon(icons.ActionInfo)
	if err != nil {
		log.Fatalf("failed to create about icon: %v", err)
	}

	navMenu.AddItem("Home", homeIcon, func() { currentPage = HomePage })
	navMenu.AddItem("About", aboutIcon, func() { currentPage = AboutPage })

	navMenu.SetSelected(int(currentPage))

	pages := []ui.Page{
		HomePage:  ui.NewHomePage(theme),
		AboutPage: ui.NewAboutPage(theme),
	}

	for {
		switch e := window.Event().(type) {
		case app.DestroyEvent:
			return e.Err
		case app.FrameEvent:
			gtx := app.NewContext(&ops, e)

			navMenu.HandleClicks(gtx)
			navMenu.SetSelected(int(currentPage))

			layout.Flex{
				Axis: layout.Horizontal,
			}.Layout(gtx,
				layout.Rigid(func(gtx layout.Context) layout.Dimensions {
					return navMenu.Layout(gtx)
				}),
				layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
					return layout.Inset{
						Top:    unit.Dp(16),
						Bottom: unit.Dp(16),
						Left:   unit.Dp(16),
						Right:  unit.Dp(16),
					}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
						return pages[currentPage].Layout(gtx)
					})
				}),
			)

			e.Frame(gtx.Ops)
		}
	}
}

const (
	HomePage = iota
	AboutPage
)