started adding the back to front api via websocket and json

engine/engineMaths.go

@@ -0,0 +1,105 @@
+package engine
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/anacrolix/torrent"
+)
+
+func secondsToMinutes(inSeconds int64) string {
+	minutes := inSeconds / 60
+	seconds := inSeconds % 60
+	minutesString := fmt.Sprintf("%d", minutes)
+	secondsString := fmt.Sprintf("%d", seconds)
+	str := minutesString + " Min/ " + secondsString + " Sec"
+	return str
+}
+
+//ConvertSizetoGB changes the sizes
+func ConvertSizetoGB(t float32, d float32) (tDelta string, dDelta string) { //converting sizes to MB or GB as needed and adding string
+	if t > 1024 && d > 1024 {
+		t := fmt.Sprintf("%.2f", t/1024)
+		t = t + " GB"
+		d := fmt.Sprintf("%.2f", d/1024)
+		d = d + " GB"
+		return t, d
+	} else if d > 1024 || t > 1024 {
+		if d > 1024 {
+			d := fmt.Sprintf("%.2f", d/1024)
+			d = d + " GB"
+			t := fmt.Sprintf("%.2f", t)
+			t = t + " MB"
+			return t, d
+		}
+		d := fmt.Sprintf("%.2f", d)
+		d = d + " MB"
+		t := fmt.Sprintf("%.2f", t/1024)
+		t = t + " GB"
+		return t, d
+	} else {
+		d := fmt.Sprintf("%.2f", d)
+		t := fmt.Sprintf("%.2f", t)
+		t = t + " MB"
+		d = d + " MB"
+		return t, d
+	}
+}
+
+//CalculateTorrentSpeed is used to calculate the torrent upload and download speed over time
+func CalculateTorrentSpeed(t *torrent.Torrent, c *ClientDB, oc ClientDB) {
+	now := time.Now()
+	bytes := t.BytesCompleted()
+	bytesUpload := t.Stats().DataBytesWritten
+	dt := float32(now.Sub(oc.UpdatedAt))     // get the delta time length between now and last updated
+	db := float32(bytes - oc.BytesCompleted) //getting the delta bytes
+	rate := db * (float32(time.Second) / dt) // converting into seconds
+	dbU := float32(bytesUpload - oc.DataBytesWritten)
+	//fmt.Println("BytesWritten", bytesUpload)
+	//fmt.Println("WireBytes", t.Stats().DataBytesWritten)
+	//fmt.Println("ChunksWritten", t.Stats().ChunksWritten)
+	rateUpload := dbU * (float32(time.Second) / dt)
+	if rate >= 0 {
+		rate = rate / 1024 / 1024 //creating integer to calculate ETA
+		c.DownloadSpeed = fmt.Sprintf("%.2f", rate)
+		c.DownloadSpeed = c.DownloadSpeed + " MB/s"
+		c.downloadSpeedInt = int64(rate)
+	}
+	if rateUpload >= 0 {
+		rateUpload = rateUpload / 1024 / 1024
+		c.UploadSpeed = fmt.Sprintf("%.2f", rateUpload)
+		c.UploadSpeed = c.UploadSpeed + " MB/s"
+
+	}
+	c.UpdatedAt = now
+}
+
+//CalculateTorrentETA is used to estimate the remaining dl time of the torrent based on the speed that the MB are being downloaded
+func CalculateTorrentETA(t *torrent.Torrent, c *ClientDB) {
+	missingBytes := t.Length() - t.BytesCompleted()
+	missingMB := missingBytes / 1024 / 1024
+	if missingMB == 0 {
+		c.ETA = "Done"
+	} else if c.downloadSpeedInt == 0 {
+		c.ETA = "N/A"
+	} else {
+		ETASeconds := missingMB / c.downloadSpeedInt
+		str := secondsToMinutes(ETASeconds) //converting seconds to minutes + seconds
+		c.ETA = str
+	}
+}
+
+//CalculateTorrentStatus is used to determine what the STATUS column of the frontend will display ll2
+func CalculateTorrentStatus(t *torrent.Torrent, c *ClientDB) {
+	if t.Seeding() && t.Stats().ActivePeers > 0 && t.BytesMissing() == 0 {
+		c.Status = "Seeding"
+	} else if t.Stats().ActivePeers > 0 && t.BytesMissing() > 0 {
+		c.Status = "Downloading"
+	} else if t.Stats().ActivePeers == 0 && t.BytesMissing() == 0 {
+		c.Status = "Completed"
+	} else if t.Stats().ActivePeers == 0 && t.BytesMissing() > 0 {
+		c.Status = "Awaiting Peers"
+	} else {
+		c.Status = "Unknown"
+	}
+}