decoupled the winIDs from the telemetry data

hell yeah, brother!

devices/cdashdisplay/display.go

@@ -8,6 +8,7 @@ import (
 	"log/slog"
 	"os"
 	"path"
+	"sync"
 	"time"
 
 	helper "esdi/helpers"
@@ -106,8 +107,10 @@ func NewCDashState() *CDashState {
 }
 
 type CDashDisplay struct {
-	WT    *communication.WalkieTalkie
-	State *CDashState
+	WT             *communication.WalkieTalkie
+	State          *CDashState
+	fieldToWindows map[telemetry.FieldID][]int16
+	bufPool        sync.Pool
 }
 
 // Connect will try to find and connect to the CDashDisplay
@@ -120,14 +123,42 @@ func NewCDashDisplay() (*CDashDisplay, error) {
 	}
 
 	return &CDashDisplay{
-		WT:    p,
-		State: NewCDashState(),
+		WT:             p,
+		State:          NewCDashState(),
+		fieldToWindows: make(map[telemetry.FieldID][]int16),
+		bufPool: sync.Pool{
+			New: func() any {
+				b := make([]byte, 0, telemetry.MaxFields*8)
+				return &b
+			},
+		},
 	}, nil
 }
 
 func (d *CDashDisplay) SendCommand() {
 }
 
+func (d *CDashDisplay) RegisterFieldMapping(fieldID telemetry.FieldID, winID int16) {
+	d.fieldToWindows[fieldID] = append(d.fieldToWindows[fieldID], winID)
+}
+
+func (d *CDashDisplay) UnregisterFieldMapping(winID int16) {
+	for fieldID, windows := range d.fieldToWindows {
+		updated := windows[:0]
+		for _, w := range windows {
+			if w != winID {
+				updated = append(updated, w)
+			}
+
+			if len(updated) == 0 {
+				delete(d.fieldToWindows, fieldID)
+			} else {
+				d.fieldToWindows[fieldID] = updated
+			}
+		}
+	}
+}
+
 func (d *CDashDisplay) CreateWindow(win *DesktopUIWindow) (*DesktopUIWindow, error) {
 	bytes, err := helper.StructToBytes(win.UIWindow)
 	if err != nil {
@@ -146,6 +177,9 @@ func (d *CDashDisplay) CreateWindow(win *DesktopUIWindow) (*DesktopUIWindow, err
 	slog.Info(fmt.Sprintf("Recived ID message: %v", wID))
 
 	d.State.Layout.AddWindow(win)
+	if fieldID, ok := telemetry.GetFieldID(win.UIData.TelemetryField); ok {
+		d.RegisterFieldMapping(fieldID, win.UIData.IDX)
+	}
 
 	return win, nil
 }
@@ -177,6 +211,8 @@ func (d *CDashDisplay) UpdateWindow(win *DesktopUIWindow) error {
 	// Yeah, same address as suspected
 	// I can't think about it right now. I'll think about that tomorrow
 
+	// TODO: need to update the field mappings here!
+
 	return nil
 }
 
@@ -199,7 +235,8 @@ func (d *CDashDisplay) DestroyWindow(wID int16) error {
 		return err
 	}
 
-	// NODE: add this
+	// NOTE: add this
+	d.UnregisterFieldMapping(wID)
 	d.State.Layout.RemoveWindow(wID)
 
 	return nil
@@ -357,7 +394,7 @@ func (d *CDashDisplay) UnloadLayout() error {
 }
 
 func (d *CDashDisplay) SendData(data *telemetry.TelemetryData) {
-	packet := data.Pack()
+	packet := d.encodePacket(data)
 
 	bytes, err := helper.StructToBytes(packet)
 	if err != nil {

devices/cdashdisplay/transportPackets.go

@@ -1,5 +1,11 @@
 package cdashdisplay
 
+import (
+	"math"
+
+	"esdi/telemetry"
+)
+
 // In this file we will place all structs that are 1:1 representation of the
 // types in the device transport layer ->
 
@@ -65,6 +71,71 @@ type UIWindowUpdatePacket struct {
 	Window UIWindow
 }
 
-// func getUIWindowDTO(w *DesktopWindowData) *UIWindow {
-//
-// }
+// TODO: this is here because this is the only device I use like this
+// once I add another serial device I will move this somewhere else that can
+// be reused by all devices but still is decoupled from the telemetry package
+func (cds *CDashDisplay) encodePacket(td *telemetry.TelemetryData) []byte {
+	bufPtr := cds.bufPool.Get().(*[]byte)
+	buf := (*bufPtr)[:0]
+
+	for fieldID, windowIDs := range cds.fieldToWindows {
+		if int(fieldID) >= len(td.Values) || len(windowIDs) == 0 {
+			continue
+		}
+
+		tf := &td.Values[fieldID]
+
+		for _, winID := range windowIDs {
+			buf = packField(winID, tf, buf)
+		}
+	}
+
+	// We have to copy here because we have to return the buffer
+	result := make([]byte, len(buf))
+	copy(result, buf)
+
+	cds.bufPool.Put(&buf)
+
+	return result
+}
+
+// Pack will pack this current TelemetryField into bytes to send over the wire
+// Format:
+// 0x00 - Field ID
+// 0x00 |
+// 0x01 - DataType
+// 0x02 - if its a (u)int8
+// or
+// 0x02 - if its a (u)int16 - first byte
+// 0x02 - if its a (u)int16 - second byte
+// or
+// 0x02 - str len max is 255 chars
+// [0x02] - str
+func packField(winID int16, tf *telemetry.TelemetryField, dest []byte) []byte {
+	// NOTE: maybe we can have a pool of these so we don't have to create them here
+	// or whatever
+	dest = append(dest, uint8(winID), uint8(winID>>8))
+	dest = append(dest, uint8(tf.Type))
+
+	switch tf.Type {
+	case telemetry.DataTypeINT8, telemetry.DataTypeUINT8, telemetry.DataTypeCHAR:
+		dest = append(dest, uint8(tf.Raw))
+	case telemetry.DataTypeINT16, telemetry.DataTypeUINT16:
+		dest = append(dest, uint8(tf.Raw), uint8(tf.Raw>>8))
+	case telemetry.DataTypeINT32, telemetry.DataTypeUINT32:
+		dest = append(dest, uint8(tf.Raw), uint8(tf.Raw>>8), uint8(tf.Raw>>16), uint8(tf.Raw>>24))
+	case telemetry.DataTypeINT64, telemetry.DataTypeUINT64:
+		dest = append(
+			dest, uint8(tf.Raw), uint8(tf.Raw>>8), uint8(tf.Raw>>16),
+			uint8(tf.Raw>>24), uint8(tf.Raw>>32), uint8(tf.Raw>>40), uint8(tf.Raw>>48),
+			uint8(tf.Raw>>56),
+		)
+	case telemetry.DataTypeSTRING:
+		l := min(len(tf.Str), math.MaxUint8)
+
+		dest = append(dest, uint8(l))
+		dest = append(dest, tf.Str[:l]...)
+	}
+
+	return dest
+}