feat: implement dynamic server list loading from API

Add internal/api package to fetch server list from /api/servers.json endpoint

Replace hardcoded server list with dynamic API call

Implement loading states, error handling, and refresh capability

internal/ui/screens/screens.go

@@ -28,27 +28,54 @@ func MainScreen(
 	serverList []Modpack,
 	onPlay func(),
 	onSettings func(),
+	onServerListRefresh func(),
+	isServerListLoading bool,
+	serverListError error,
 ) fyne.CanvasObject {
 
 	// ── Sidebar (Left) ──────────────────────────────────────
-	serverLabels := make([]*widget.Label, len(serverList))
-	serverContainer := container.NewVBox()
+	var sidebar fyne.CanvasObject
+	if isServerListLoading {
+		// Show loading state
+		loadingLabel := widget.NewLabelWithStyle("Loading server list...", fyne.TextAlignCenter, fyne.TextStyle{})
+		sidebar = container.NewVScroll(container.NewVBox(loadingLabel))
+	} else if len(serverList) == 0 && serverListError == nil {
+		// Show empty state (no error, just empty list)
+		emptyLabel := widget.NewLabelWithStyle("No servers available", fyne.TextAlignCenter, fyne.TextStyle{})
+		sidebar = container.NewVScroll(container.NewVBox(emptyLabel))
+	} else if serverListError != nil {
+		// Show error state
+		errorLabel := widget.NewLabelWithStyle("Failed to load server list", fyne.TextAlignCenter, fyne.TextStyle{})
+		detailLabel := widget.NewLabel(serverListError.Error())
+		detailLabel.Wrapping = fyne.TextWrapWord
+		retryBtn := components.SettingsButton(onServerListRefresh)
+		retryBtn.Text = "Retry"
+		sidebar = container.NewVScroll(container.NewVBox(
+			errorLabel,
+			detailLabel,
+			retryBtn,
+		))
+	} else {
+		// Show normal server list
+		serverLabels := make([]*widget.Label, len(serverList))
+		serverContainer := container.NewVBox()
 
-	for i, sp := range serverList {
-		label := widget.NewLabel(sp.Name)
-		serverLabels[i] = label
-		index := i
-		card := components.ServerCard(sp.Name, index == 0, func() {
-			for j, l := range serverLabels {
-				l.TextStyle.Bold = (j == index)
-				l.Refresh()
-			}
-		})
-		serverContainer.Add(card)
+		for i, sp := range serverList {
+			label := widget.NewLabel(sp.Name)
+			serverLabels[i] = label
+			index := i
+			card := components.ServerCard(sp.Name, index == 0, func() {
+				for j, l := range serverLabels {
+					l.TextStyle.Bold = (j == index)
+					l.Refresh()
+				}
+			})
+			serverContainer.Add(card)
+		}
+
+		sidebar = container.NewVScroll(serverContainer)
 	}
 
-	sidebar := container.NewVScroll(serverContainer)
-
 	// ── Center (background + info) ──────────────────────────
 	bg := widget.NewRichTextFromMarkdown(
 		"# Welcome to MrixsCraft\n\n" +
@@ -93,9 +120,14 @@ func MainScreen(
 	playBtn := components.PlayButton(onPlay)
 	settingsBtn := components.SettingsButton(onSettings)
 
+	// Refresh button for server list
+	refreshBtn := components.SettingsButton(onServerListRefresh)
+
 	bottomRight := container.NewHBox(
 		settingsBtn,
 		widget.NewSeparator(),
+		refreshBtn,
+		widget.NewSeparator(),
 		playBtn,
 	)
 

internal/ui/screens/screens_test.go

@@ -0,0 +1,10 @@
+// package screens implements application screens (login, main menu, settings).
+package screens
+
+import "testing"
+
+// Dummy test to ensure package compiles
+func TestScreensPackage_Compiles(t *testing.T) {
+	// This test ensures the screens package compiles without errors
+	// We're not testing the actual UI output as that requires a GUI environment
+}

internal/ui/ui.go

@@ -5,6 +5,7 @@ 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"
@@ -20,12 +21,13 @@ func Launch(client *auth.Client, session *auth.Session, settings config.Settings
 	w.Resize(fyne.NewSize(float32(settings.Width), float32(settings.Height)))
 	w.CenterOnScreen()
 
-	// TODO: fetch from /api/servers.json
-	serverList := []screens.Modpack{
-		{Slug: "hitech", Name: "HiTech 1.21"},
-		{Slug: "vanilla", Name: "Vanilla 1.20"},
-	}
+					// 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
 	}
@@ -38,15 +40,38 @@ func Launch(client *auth.Client, session *auth.Session, settings config.Settings
 		})
 	}
 
-	content := screens.MainScreen(w, client, session, serverList, onPlay, onSettings)
+	// 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)
+			content := screens.MainScreen(w, client, sess, serverList, onPlay, onSettings, refreshServerList, isServerListLoading, serverListError)
 			w.SetContent(content)
 		})
 	}

internal/ui/ui_test.go

@@ -0,0 +1,9 @@
+// package ui contains the Fyne GUI bootstrap and wiring.
+package ui
+
+import "testing"
+
+// Dummy test to ensure package compiles
+func TestUIPackage_Compiles(t *testing.T) {
+	// This test ensures the ui package compiles without errors
+}