Start building out robust UI code ; this update moves the fim slideshow advancing into the go code and keeps fim OFF stdin/out so keyboard input shouldn't affect it

cmd/ui/ui.go

@@ -1,17 +1,23 @@
 package main
 
 import (
-	"fmt"
+	"io"
 	"log"
 	"os"
 	"os/exec"
 	"os/signal"
 	"syscall"
+	"time"
 
 	"github.com/gdamore/tcell"
 	"github.com/rivo/tview"
 )
 
+const (
+	CMD_FIM            = "/usr/local/bin/pf-fim.sh"
+	SLIDESHOW_INTERVAL = 300 * time.Second
+)
+
 func main() {
 	// fim placeholder so we can operate on it when a signal is received
 	var fim *exec.Cmd = nil
@@ -26,32 +32,59 @@ func main() {
 		for range sigs {
 			if fim != nil { // Just in case someone lays on ctrl-c or similar during startup
 				if err := fim.Process.Kill(); err != nil {
-					log.Fatalf("failed to kill process: %s", err)
+					log.Fatalf("failed to kill fim : %s", err)
 				}
 			}
 		}
 	}()
 
-	// Forever run slideshow / show ui as the main program executed on a PiFrame
-	for {
-		// Run slideshow
-		fim = exec.Command("/usr/local/bin/pf-fim.sh")
-		if err := fim.Run(); err != nil {
-			// Unwrap the error a bit so we can find out if a signal killed fim or something else
-			// An exit code of -1 means the program didn't exit in time or was terminated by a signal (per the docs)
-			if exitError, ok := err.(*exec.ExitError); ok && exitError.ExitCode() != -1 {
-				log.Fatalf("Error : %s", err)
+	// Run slideshow
+	fim = exec.Command(CMD_FIM)
+
+	// Setup stdin for fim to control slideshow
+	stdin, err := fim.StdinPipe()
+	if err != nil {
+		log.Fatalf("Error getting fim stdin : %s", err)
+	}
+
+	// Advance slideshow every interval as defined in const()
+	ticker := time.NewTicker(SLIDESHOW_INTERVAL)
+	stop_ticker := make(chan struct{})
+	go func() {
+		for {
+			select {
+			case <-ticker.C:
+				_, err = io.WriteString(stdin, "n")
+				if err != nil {
+					log.Fatalf("Error advancing slides : %s", err)
+				}
+			case <-stop_ticker:
+				ticker.Stop()
+				stdin.Close()
+				return
 			}
 		}
+	}()
 
-		// Run config UI when slideshow stops
-		app := tview.NewApplication()
-		frame := tview.NewFrame(tview.NewBox().SetBackgroundColor(tcell.ColorBlack)).
-			SetBorders(2, 2, 2, 2, 4, 4).
-			AddText("PiFrame", true, tview.AlignCenter, tcell.ColorWhite).
-			AddText("Configuration Utility", true, tview.AlignCenter, tcell.ColorRed)
-		if err := app.SetRoot(frame, true).EnableMouse(true).Run(); err != nil {
-			log.Fatal(err)
+	// Run fim
+	if err := fim.Run(); err != nil {
+		// Unwrap the error a bit so we can find out if a signal killed fim or something else
+		// An exit code of -1 means the program didn't exit in time or was terminated by a signal (per the docs)
+		if exitError, ok := err.(*exec.ExitError); ok && exitError.ExitCode() != -1 {
+			log.Fatalf("Error running fim : %s", err)
 		}
 	}
+
+	// Stop fim slideshow advancing go routine
+	close(stop_ticker)
+
+	// Run config UI when slideshow stops
+	app := tview.NewApplication()
+	frame := tview.NewFrame(tview.NewBox().SetBackgroundColor(tcell.ColorBlack)).
+		SetBorders(2, 2, 2, 2, 4, 4).
+		AddText("PiFrame", true, tview.AlignCenter, tcell.ColorWhite).
+		AddText("Configuration Utility", true, tview.AlignCenter, tcell.ColorRed)
+	if err := app.SetRoot(frame, true).EnableMouse(true).Run(); err != nil {
+		log.Fatalf("Error running UI : %s", err)
+	}
 }