// package ui contains the Fyne GUI bootstrap and wiring.
package ui

import (
	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/app"

	"gitea.mrixs.me/Mrixs/MrixsCraft-launcher/internal/api"
	"gitea.mrixs.me/Mrixs/MrixsCraft-launcher/internal/auth"
	"gitea.mrixs.me/Mrixs/MrixsCraft-launcher/internal/config"
	"gitea.mrixs.me/Mrixs/MrixsCraft-launcher/internal/ui/screens"
	"gitea.mrixs.me/Mrixs/MrixsCraft-launcher/internal/ui/theme"
)

// Launch initialises the Fyne application with the Minecraft theme and shows the main window.
func Launch(client *auth.Client, session *auth.Session, settings config.Settings) {
	a := app.New()
	a.Settings().SetTheme(&theme.MinecraftTheme{})

	w := a.NewWindow("MrixsCraft")
	w.Resize(fyne.NewSize(float32(settings.Width), float32(settings.Height)))
	w.CenterOnScreen()

					// State for server list loading
	var serverList []screens.Modpack
	var isServerListLoading bool
	var serverListError error
	_ = serverListError // Use variable to prevent "declared and not used" error

	// Callback functions
	onPlay := func() {
		// TODO: launch selected modpack
	}

	onSettings := func() {
		screens.SettingsScreen(w, func(memoryMB int, extraArgs string) {
			settings.MemoryMB = memoryMB
			settings.ExtraArgs = extraArgs
			_ = config.Save(settings)
		})
	}

	// Function to refresh server list
	var refreshServerList func()
	refreshServerList = func() {
		isServerListLoading = true
		serverListError = nil
		// Update UI to show loading state
		content := screens.MainScreen(w, client, session, serverList, onPlay, onSettings, refreshServerList, isServerListLoading, serverListError)
		w.SetContent(content)

		// Fetch server list in goroutine to avoid blocking UI
		go func() {
			serverList, serverListError = api.FetchServerList(settings.ServerURL)
			isServerListLoading = false
			// Update UI with result
			content := screens.MainScreen(w, client, session, serverList, onPlay, onSettings, refreshServerList, isServerListLoading, serverListError)
			w.SetContent(content)
		}()
	}

	// Initial load of server list
	content := screens.MainScreen(w, client, session, serverList, onPlay, onSettings, refreshServerList, isServerListLoading, serverListError)
	w.SetContent(content)

	// Start fetching server list in background
	go refreshServerList()

	// If no session, show login modal after the window is rendered.
	if session == nil {
		w.Show()
		screens.LoginScreen(w, client, func(sess *auth.Session) {
			// Refresh UI with logged-in state.
			content := screens.MainScreen(w, client, sess, serverList, onPlay, onSettings, refreshServerList, isServerListLoading, serverListError)
			w.SetContent(content)
		})
	}

	w.ShowAndRun()
}