implement notifications

ui/notify.go

@@ -0,0 +1,169 @@
+package ui
+
+import (
+	"sync"
+	"time"
+
+	"github.com/aditya-K2/utils"
+
+	"github.com/gdamore/tcell/v2"
+	"github.com/rivo/tview"
+)
+
+var (
+	maxNotifications = 3
+	pm               sync.Mutex
+	notAvailable     = -1
+	posArr           = positionArray{}
+	c                chan *notification
+)
+
+// Start Notification Service
+func InitNotifier() {
+	for _m := maxNotifications; _m != 0; _m-- {
+		posArr = append(posArr, true)
+	}
+	c = make(chan *notification, maxNotifications)
+	routine()
+}
+
+// notification Primitive
+type notification struct {
+	*tview.Box
+	Text     string
+	Position int
+	close    chan bool
+	timer    time.Duration
+}
+
+// Array for all available positions where the notification can be displayed.
+type positionArray []bool
+
+// Check If there is a position available.
+func (p *positionArray) Available() bool {
+	var t = false
+	pm.Lock()
+	for _, v := range *p {
+		t = t || v
+	}
+	pm.Unlock()
+	return t
+}
+
+func (p *positionArray) GetNextPosition() int {
+	pm.Lock()
+	v := *p
+	for k := range v {
+		if v[k] {
+			v[k] = false
+			pm.Unlock()
+			return k
+		}
+	}
+	pm.Unlock()
+	return notAvailable
+}
+
+// Free a position
+func (p *positionArray) Free(i int) {
+	pm.Lock()
+	v := *p
+	v[i] = true
+	pm.Unlock()
+}
+
+// Get A Pointer to A Notification Struct
+func newNotificationWithTimer(s string, t time.Duration) *notification {
+	return &notification{
+		Box:   tview.NewBox(),
+		Text:  s,
+		timer: t,
+		close: nil,
+	}
+}
+
+// Get A Pointer to A Notification Struct with a close channel
+func newNotificationWithChan(s string, c chan bool) *notification {
+	return &notification{
+		Box:   tview.NewBox(),
+		Text:  s,
+		close: c,
+	}
+}
+
+// Draw Function for the Notification Primitive
+func (self *notification) Draw(screen tcell.Screen) {
+	termDetails := utils.GetWidth()
+	pos := (self.Position*3 + self.Position + 1)
+
+	var (
+		COL          int = int(termDetails.Col)
+		TEXTLENGTH   int = len(self.Text)
+		HEIGHT       int = 3
+		TextPosition int = 1
+	)
+
+	self.Box.SetBackgroundColor(tcell.ColorBlack)
+	self.SetRect(COL-(TEXTLENGTH+7), pos, TEXTLENGTH+4, HEIGHT)
+	self.DrawForSubclass(screen, self.Box)
+	tview.Print(screen, self.Text,
+		COL-(TEXTLENGTH+5), pos+TextPosition, TEXTLENGTH,
+		tview.AlignCenter, tcell.ColorWhite)
+}
+
+// this routine checks for available position and sends notification if
+// position is available.
+func routine() {
+	go func() {
+		for {
+			val := <-c
+			// Wait until a new position isn't available
+			for !posArr.Available() {
+				continue
+			}
+			notify(val)
+		}
+	}()
+}
+
+func notify(n *notification) {
+	go func() {
+		currentTime := time.Now().String()
+		npos := posArr.GetNextPosition()
+		// Ensure a position is available.
+		if npos == notAvailable {
+			for !posArr.Available() {
+			}
+			npos = posArr.GetNextPosition()
+		}
+		n.Position = npos
+		Ui.Root.Root.AddPage(currentTime, n, false, true)
+		Ui.App.SetFocus(Ui.Main.Table)
+		if n.close != nil {
+			<-n.close
+		} else {
+			time.Sleep(n.timer)
+		}
+		Ui.Root.Root.RemovePage(currentTime)
+		posArr.Free(npos)
+		Ui.App.SetFocus(Ui.Main.Table)
+	}()
+}
+
+func SendNotification(text string) {
+	SendNotificationWithTimer(text, time.Second)
+}
+
+func SendNotificationWithTimer(text string, t time.Duration) {
+	go func() {
+		c <- newNotificationWithTimer(text, t)
+	}()
+}
+
+func SendNotificationWithChan(text string) chan bool {
+	close := make(chan bool)
+	go func() {
+		c <- newNotificationWithChan(text, close)
+	}()
+	return close
+}

ui/view_playlist.go

@@ -21,7 +21,15 @@ func (p *PlaylistView) Content() [][]Content {
 	c := make([][]Content, 0)
 	if p.currentPlaylist != nil {
 		if p.currentUserFullPlaylist == nil {
-			pf, err := spt.GetPlaylist(p.currentPlaylist.ID, func(bool, error) {})
+			c := SendNotificationWithChan("Loading Playlist....")
+			pf, err := spt.GetPlaylist(p.currentPlaylist.ID, func(s bool, e error) {
+				c <- true
+				if !s {
+					SendNotification(e.Error())
+				} else {
+					SendNotification("Playlist Loaded Succesfully")
+				}
+			})
 			if err != nil {
 				panic(err)
 			}