Add a status pane for temporarily displaying status messages

app/app.go

@@ -1,8 +1,8 @@
 package app
 
 import (
+	"fmt"
 	"io/ioutil"
-	"log"
 	"net/http"
 	"time"
 
@@ -27,8 +27,8 @@ func PlayChannel(chn *components.ChannelItem, ctx *context.AppContext) {
 		client := &http.Client{}
 		req, _ := http.NewRequest("GET", chn.Playlist, nil)
 		resp, err := client.Do(req)
-		if err != nil {
+		if err != nil || resp.StatusCode != 200 {
-			log.Fatal(err)
+			ctx.SetStatusMessage(fmt.Sprintf("Unable to stream channel: %s", chn.Name))
 		}
 		defer resp.Body.Close()
 
@@ -65,6 +65,7 @@ func TogglePause(ctx *context.AppContext) {
 	ctx.IsPlaying = !ctx.IsPlaying
 }
 
+// UpdateNowPlaying updates the application's now playing view with the currently playing channel
 func UpdateNowPlaying(chn *components.ChannelItem, ctx *context.AppContext) {
 	ctx.CurrentChannel = chn
 	cp := difm.GetCurrentlyPlaying(ctx)

components/components.go

@@ -30,3 +30,9 @@ type Track struct {
 	Duration  float64   `json:"duration"`
 	StartTime time.Time `json:"start_time"`
 }
+
+// StatusMessage is a message to display in the application for a fixed period of time
+type StatusMessage struct {
+	Message  string
+	Duration time.Duration
+}

context/context.go

@@ -1,6 +1,8 @@
 package context
 
 import (
+	"time"
+
 	"github.com/acaloiaro/di-tui/components"
 	"github.com/acaloiaro/di-tui/views"
 	"github.com/faiface/beep"
@@ -8,17 +10,40 @@ import (
 
 // CreateAppContext creates the application context
 func CreateAppContext(view *views.ViewContext) *AppContext {
-	ctx := &AppContext{View: view}
+	ctx := &AppContext{
+		View:          view,
+		StatusChannel: make(chan components.StatusMessage, 1),
+	}
 
 	return ctx
 }
 
 // AppContext is a shared context to be shared across the application
+// AudioStream - The raw audio stream used by the beep library to stream audio
+// CurrentChannel - The ChannelItem representing the currently playing di.fm channel
+// DfmToken - The token used to authenticate to di.fm
+// IsPlaying - Is there audio playing?
+// SpeakerInitialized - Has the speaker been initialized with a bitrate?
+// View - The view context
+// Status - Gets and sets current application status messages
 type AppContext struct {
 	AudioStream        beep.StreamSeekCloser
 	CurrentChannel     *components.ChannelItem
 	DifmToken          string
 	IsPlaying          bool
+	ShowStatus         bool // The status pane will be visible when true
 	SpeakerInitialized bool
+	StatusChannel      chan components.StatusMessage
 	View               *views.ViewContext
 }
+
+// SetStatusMessage sets the application's status message for three seconds.
+func (c *AppContext) SetStatusMessage(msg string) {
+	c.SetStatusMessageTimed(msg, 5*time.Second)
+}
+
+// SetStatusMessageTimed sets the application's status message for a fixed period of time.
+func (c *AppContext) SetStatusMessageTimed(msg string, d time.Duration) {
+	c.ShowStatus = true
+	c.StatusChannel <- components.StatusMessage{Message: msg, Duration: d}
+}

di-tui.go

@@ -39,7 +39,7 @@ func main() {
 		os.Exit(1)
 	}
 
-	ctx = context.CreateAppContext(views.CreateAppView())
+	ctx = context.CreateAppContext(views.CreateViewContext())
 	ctx.DifmToken = token
 
 	run()
@@ -47,20 +47,19 @@ func main() {
 
 func run() {
 	configureEventHandling()
+	updateScreenLayout()
 	configureUIComponents()
-	layout := buildUILayout()
 
-	err := ctx.View.App.
+	err := ctx.View.App.Run()
-		SetRoot(layout, true).
-		SetFocus(ctx.View.FavoriteList).
-		Run()
 
 	if err != nil {
 		panic(err)
 	}
 }
 
-func buildUILayout() *tview.Flex {
+func updateScreenLayout() {
+	focusView := ctx.View.App.GetFocus()
+
 	main := tview.NewFlex()
 	main.SetDirection(tview.FlexRow)
 
@@ -69,20 +68,29 @@ func buildUILayout() *tview.Flex {
 		AddItem(ctx.View.ChannelList, 0, 2, false).
 		SetDirection(tview.FlexRow)
 
-	flex := tview.NewFlex()
+	primaryView := tview.NewFlex()
-	flex.
+	primaryView.
 		AddItem(favsAndChannels, 30, 0, false).
 		AddItem(ctx.View.NowPlaying, 0, 4, false)
 
+	if ctx.ShowStatus {
+		main.AddItem(ctx.View.Status, 4, 0, false)
+	}
+
 	main.
-		AddItem(flex, 0, 3, false).
+		AddItem(primaryView, 0, 3, false).
 		AddItem(ctx.View.Keybindings, 4, 0, false)
 
-	return main
+	if focusView == nil {
+		focusView = ctx.View.FavoriteList
+	}
+
+	ctx.View.App.
+		SetRoot(main, true).
+		SetFocus(focusView)
 }
 
 func configureEventHandling() {
-
 	ctx.View.App.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
 		focus := ctx.View.App.GetFocus().(*tview.List)
 
@@ -130,12 +138,26 @@ func configureEventHandling() {
 			ctx.View.App.QueueUpdateDraw(func() {})
 		}
 	}()
+
+	// display the status pane when new status messages arrive
+	go func() {
+		for {
+			status := <-ctx.StatusChannel
+			ctx.View.Status.Message = status.Message
+			updateScreenLayout() // add the status pane to the screen
+
+			<-time.Tick(status.Duration)
+			ctx.ShowStatus = false
+			updateScreenLayout() // remove the status pane from the screen
+		}
+	}()
+
 }
 
 func configureUIComponents() {
 
 	// configure the channel list
-	channels := difm.ListChannels()
+	channels := difm.ListChannels(ctx)
 	for _, chn := range channels {
 		ctx.View.ChannelList.AddItem(chn.Name, "", 0, func() {
 			chn := channels[ctx.View.ChannelList.GetCurrentItem()]

difm/difm.go

@@ -81,16 +81,17 @@ func GetCurrentlyPlaying(ctx *context.AppContext) (currentlyPlaying components.C
 	client := &http.Client{}
 	req, _ := http.NewRequest("GET", "https://www.di.fm/_papi/v1/di/currently_playing", nil)
 	resp, err := client.Do(req)
-	if err != nil {
+	if err != nil || resp.StatusCode != 200 {
+		ctx.SetStatusMessage("Unable to fetch currently playing track info.")
 		return
 	}
 	defer resp.Body.Close()
 
 	body, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
+	if err != nil || resp.StatusCode != 200 {
-		// TODO: Don't exit here. Once there's a status message area in the app, populate it with the error
+		ctx.SetStatusMessage("Unable to fetch currently playing track info.")
-		log.Println("unable to list channels", err.Error())
+
-		os.Exit(1)
+		return
 	}
 
 	var currentlyPlayingStations []components.CurrentlyPlaying
@@ -106,7 +107,7 @@ func GetCurrentlyPlaying(ctx *context.AppContext) (currentlyPlaying components.C
 }
 
 // ListChannels lists all premium MP3 channels
-func ListChannels() (channels []components.ChannelItem) {
+func ListChannels(ctx *context.AppContext) (channels []components.ChannelItem) {
 	client := &http.Client{}
 	req, _ := http.NewRequest("GET", "http://listen.di.fm/premium_high", nil)
 	resp, err := client.Do(req)
@@ -117,15 +118,16 @@ func ListChannels() (channels []components.ChannelItem) {
 
 	body, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
-		// TODO: Don't exit here. Once there's a status message area in the app, populate it with the error
+		msg := fmt.Sprintf("Unable to fetch the list of channels: %s", err.Error())
-		log.Println("unable to list channels", err.Error())
+		ctx.SetStatusMessage(msg)
-		os.Exit(1)
+		return
 	}
 
 	err = json.Unmarshal(body, &channels)
 	if err != nil {
-		// TODO: Don't exit here. Once there's a status message area in the app, populate it with the error
+		msg := fmt.Sprintf("Unable to fetch the list of channels: %s", err.Error())
-		log.Panicf("unable to fetch channel list: %e", err)
+		ctx.SetStatusMessage(msg)
+		return
 	}
 
 	return
@@ -146,8 +148,8 @@ func ListFavorites(ctx *context.AppContext) (favorites []components.FavoriteItem
 	body, err := ioutil.ReadAll(resp.Body)
 	cfg, err := ini.Load(body)
 	if err != nil {
-		// TODO: show an message in a status UI element of the app
+		msg := fmt.Sprintf("There was a problem fetching your favorites: %s", err.Error())
-		fmt.Printf("favorite list parsing failed: %v\n", err.Error())
+		ctx.SetStatusMessage(msg)
 		return
 	}
 
@@ -172,16 +174,16 @@ func Stream(url string, ctx *context.AppContext) (format beep.Format) {
 	req, _ := http.NewRequest("GET", u, nil)
 	resp, err := client.Do(req)
 	if err != nil {
-		// TODO: Don't exit here. Once there's a status message area in the app, populate it with the error
+		msg := fmt.Sprintf("There was a problem streaming this channel channels: %s", err.Error())
-		log.Println("unable to stream channel", err.Error())
+		ctx.SetStatusMessage(msg)
-		os.Exit(1)
+		return
 	}
 
 	ctx.AudioStream, format, err = mp3.Decode(resp.Body)
 	if err != nil {
-		// TODO: Don't exit here. Once there's a status message area in the app, populate it with the error
+		msg := fmt.Sprintf("There was a problem streaming this channel channels: %s", err.Error())
-		log.Println("unable to stream channel:", resp.StatusCode)
+		ctx.SetStatusMessage(msg)
-		os.Exit(1)
+		return
 	}
 
 	return

views/views.go

@@ -13,8 +13,9 @@ type ViewContext struct {
 	App          *tview.Application
 	ChannelList  *tview.List
 	FavoriteList *tview.List
-	NowPlaying   *NowPlayingView
 	Keybindings  *KeybindingView
+	NowPlaying   *NowPlayingView
+	Status       *StatusView
 }
 
 // KeybindingView is a custom view for dispalying the keyboard bindings available to users
@@ -25,41 +26,56 @@ type KeybindingView struct {
 
 // UIKeybinding is a helper struct for building a ControlsView
 type UIKeybinding struct {
-	Shortcut    string // a keybinding to bind to this control
 	Description string // a description of what the keybinding does
 	Func        func() // the funcion to execute when the binding is pressed
-}
+	Shortcut    string // a keybinding to bind to this control
-
-// CreateAppView creates the primary application view of di-tui
-func CreateAppView() *ViewContext {
-	return &ViewContext{
-		App:          tview.NewApplication(),
-		ChannelList:  createChannelList(),
-		FavoriteList: createFavoriteList(),
-		NowPlaying:   newNowPlaying(),
-		Keybindings:  createKeybindings(),
-	}
 }
 
 // NowPlayingView is a custom view for dispalying the currently playing channel
 type NowPlayingView struct {
 	*tview.Box
 	Channel *components.ChannelItem
-	Track   components.Track
 	Elapsed float64
+	Track   components.Track
 }
 
-func newNowPlaying() *NowPlayingView {
+// StatusView shows temporary status messages in the application
-	np := &NowPlayingView{
+type StatusView struct {
-		Box:     tview.NewBox(),
+	*tview.Box
-		Channel: &components.ChannelItem{},
+	Message string
-		Elapsed: 0.0,
+}
+
+// CreateViewContext creates the primary application view of di-tui
+func CreateViewContext() *ViewContext {
+	return &ViewContext{
+		App:          tview.NewApplication(),
+		ChannelList:  createChannelList(),
+		FavoriteList: createFavoriteList(),
+		Keybindings:  createKeybindings(),
+		NowPlaying:   createNowPlaying(),
+		Status:       createStatusView(),
 	}
+}
 
-	np.SetTitle(" Now Playing ")
+// Draw draws the key bindings view on to the screen
-	np.SetBorder(true)
+func (n *KeybindingView) Draw(screen tcell.Screen) {
+	n.Box.Draw(screen)
+	x, y, width, _ := n.GetInnerRect()
 
-	return np
+	previousWidth := 0
+	for j, bnd := range n.Bindings {
+		line := fmt.Sprintf("(%s)[white] %s", bnd.Shortcut, bnd.Description)
+		tview.Print(screen, line, x+previousWidth, y, width, tview.AlignLeft, tcell.ColorBlue)
+		previousWidth += len(bnd.Shortcut) + len(bnd.Description) + 4
+
+		// virtically separate playback controls from ui controls
+		// yes, this is hacky, but there's a comment, so it's ok, right?
+		// TODO clean up this mess
+		if j == 4 {
+			y = y + 1
+			previousWidth = 0
+		}
+	}
 }
 
 // Draw draws a NowPlayingView onto the scren
@@ -86,24 +102,14 @@ func (n *NowPlayingView) Draw(screen tcell.Screen) {
 	tview.Print(screen, line, x, y+3, width, tview.AlignLeft, tcell.ColorBlue)
 }
 
-// Draw draws the key bindings view on to the screen
+// Draw draws a NowPlayingView onto the scren
-func (n *KeybindingView) Draw(screen tcell.Screen) {
+func (s *StatusView) Draw(screen tcell.Screen) {
-	n.Box.Draw(screen)
-	x, y, width, _ := n.GetInnerRect()
 
-	previousWidth := 0
+	s.Box.Draw(screen)
-	for j, bnd := range n.Bindings {
+	x, y, width, _ := s.GetInnerRect()
-		line := fmt.Sprintf("(%s)[white] %s", bnd.Shortcut, bnd.Description)
-		tview.Print(screen, line, x+previousWidth, y, width, tview.AlignLeft, tcell.ColorBlue)
-		previousWidth += len(bnd.Shortcut) + len(bnd.Description) + 4
 
-		// virtically separate playback controls from ui controls
+	line := fmt.Sprintf("%s[white] %s", "Message:", s.Message)
-		// yes, this is hacky, but there's a comment, so it's ok, right?
+	tview.Print(screen, line, x, y, width, tview.AlignLeft, tcell.ColorBlue)
-		if j == 4 {
-			y = y + 1
-			previousWidth = 0
-		}
-	}
 }
 
 func createChannelList() *tview.List {
@@ -134,3 +140,27 @@ func createKeybindings() *KeybindingView {
 
 	return kbv
 }
+
+func createNowPlaying() *NowPlayingView {
+	np := &NowPlayingView{
+		Box:     tview.NewBox(),
+		Channel: &components.ChannelItem{},
+		Elapsed: 0.0,
+	}
+
+	np.SetTitle(" Now Playing ")
+	np.SetBorder(true)
+
+	return np
+}
+
+func createStatusView() *StatusView {
+	sv := &StatusView{
+		Box:     tview.NewBox(),
+		Message: "Ready to Play",
+	}
+	sv.SetTitle(" Status ")
+	sv.SetBorder(true)
+
+	return sv
+}