videochess bot behaves correctly if chess engine (stockfish) can't be found

cleanup up how bo GUI features are requested/discarded

bots/bots.go

@@ -56,5 +56,5 @@ type Feedback struct {
 type Bot interface {
 	BotID() string
 	Quit()
-	Feedback() Feedback
+	Feedback() *Feedback
 }

bots/chess/uci/uci.go

@@ -24,6 +24,7 @@ import (
 	"time"
 
 	"github.com/jetsetilly/gopher2600/bots"
+	"github.com/jetsetilly/gopher2600/curated"
 	"github.com/jetsetilly/gopher2600/logger"
 )
 
@@ -71,28 +72,35 @@ func NewUCI(pathToEngine string, diagnostic chan bots.Diagnostic) (*UCI, error)
 
 	uci.stdin, err = cmd.StdinPipe()
 	if err != nil {
-		return nil, err
+		return nil, curated.Errorf("uci: %s", err.Error())
 	}
 
 	uci.stdout, err = cmd.StdoutPipe()
 	if err != nil {
-		return nil, err
+		return nil, curated.Errorf("uci: %s", err.Error())
 	}
 
-	end := make(chan error)
+	done := make(chan error)
 	go func() {
-		err := cmd.Run()
+		err := cmd.Start()
 		if err != nil {
-			end <- err
+			done <- err
 			return
 		}
+		done <- nil
+
 		err = cmd.Wait()
 		if err != nil {
-			end <- err
+			logger.Logf("uci", err.Error())
 			return
 		}
 	}()
 
+	err = <-done
+	if err != nil {
+		return nil, curated.Errorf("uci: %s", err.Error())
+	}
+
 	return uci, nil
 }
 

bots/chess/videochess.go

@@ -509,7 +509,7 @@ func NewVideoChess(vcs bots.VCS, tv bots.TV) (bots.Bot, error) {
 
 	uci, err := uci.NewUCI("/usr/local/bin/stockfish", bot.feedback.Diagnostic)
 	if err != nil {
-		return nil, curated.Errorf("bot: %v", err)
+		return nil, curated.Errorf("videochess: %v", err)
 	}
 
 	uci.Start()
@@ -687,6 +687,6 @@ func (bot *videoChessBot) Quit() {
 }
 
 // Feedback implements the bots.Bot interface.
-func (bot *videoChessBot) Feedback() bots.Feedback {
-	return bot.feedback
+func (bot *videoChessBot) Feedback() *bots.Feedback {
+	return &bot.feedback
 }

bots/wrangler/bots.go

@@ -41,7 +41,7 @@ func NewBots(vcs bots.VCS, tv bots.TV) *Bots {
 }
 
 // ActivateBot uses the cartridge hash value to and loads any available bot.
-func (b *Bots) ActivateBot(cartHash string) (bots.Feedback, error) {
+func (b *Bots) ActivateBot(cartHash string) (*bots.Feedback, error) {
 	b.Quit()
 
 	var err error
@@ -50,12 +50,12 @@ func (b *Bots) ActivateBot(cartHash string) (bots.Feedback, error) {
 	case "043ef523e4fcb9fc2fc2fda21f15671bf8620fc3":
 		b.running, err = chess.NewVideoChess(b.vcs, b.tv)
 		if err != nil {
-			return bots.Feedback{}, curated.Errorf("bots: %v", err)
+			return nil, curated.Errorf("bots: %v", err)
 		}
 		logger.Logf("bots", "%s start", b.running.BotID())
 
 	default:
-		return bots.Feedback{}, nil
+		return nil, nil
 	}
 
 	return b.running.Feedback(), nil

debugger/debugger.go

@@ -565,6 +565,7 @@ func (dbg *Debugger) setMode(mode emulation.Mode) error {
 
 // End cleans up any resources that may be dangling.
 func (dbg *Debugger) end() {
+	dbg.removeComparisonEmulation()
 	dbg.bots.Quit()
 	dbg.vcs.End()
 
@@ -757,6 +758,9 @@ func (dbg *Debugger) reset(newCartridge bool) error {
 // this is the glue that hold the cartridge and disassembly packages together.
 // especially important is the repointing of the symbols table in the instance of dbgmem.
 func (dbg *Debugger) attachCartridge(cartload cartridgeloader.Loader) (e error) {
+	// stop any existing bots
+	dbg.bots.Quit()
+
 	dbg.setState(emulation.Initialising)
 
 	// set state after initialisation according to the emulation mode
@@ -896,8 +900,10 @@ func (dbg *Debugger) attachCartridge(cartload cartridgeloader.Loader) (e error)
 	// activate bot if possible
 	feedback, err := dbg.bots.ActivateBot(dbg.vcs.Mem.Cart.Hash)
 	if err != nil {
-		return curated.Errorf("debugger: %v", err)
+		logger.Logf("debugger", err.Error())
 	}
+
+	// always ReqBotFeedback. if feedback is nil then the bot features will be disbaled
 	err = dbg.gui.SetFeature(gui.ReqBotFeedback, feedback)
 	if err != nil {
 		return curated.Errorf("debugger: %v", err)

gui/requests.go

@@ -72,8 +72,9 @@ const (
 	// request for a comparison window to be opened
 	ReqComparison FeatureReq = "ReqComparison" // chan *image.RGBA, chan *image.RGBA
 
-	// request for a bot window to be opened
-	ReqBotFeedback FeatureReq = "ReqBotFeedback" // bots.Feedback
+	// request for bot features to be enabled. a nil argument will cause the
+	// bot features to be removed
+	ReqBotFeedback FeatureReq = "ReqBotFeedback" // *bots.Feedback
 )
 
 // Sentinal error returned if GUI does no support requested feature.

gui/sdlimgui/requests.go

@@ -144,10 +144,8 @@ func (img *SdlImgui) serviceSetFeature(request featureRequest) {
 	case gui.ReqBotFeedback:
 		err = argLen(request.args, 1)
 		if err == nil {
-			if request.args[0] != nil {
-				f := request.args[0].(bots.Feedback)
-				img.wm.windows[winBotID].(*winBot).startBotSession(f)
-			}
+			f := request.args[0].(*bots.Feedback)
+			img.wm.windows[winBotID].(*winBot).startBotSession(f)
 		}
 
 	default:

gui/sdlimgui/win_bot.go

@@ -35,7 +35,7 @@ type winBot struct {
 	dirty       bool
 
 	// render channels are given to use by the main emulation through a GUI request
-	feedback bots.Feedback
+	feedback *bots.Feedback
 }
 
 func newWinBot(img *SdlImgui) (window, error) {
@@ -64,7 +64,7 @@ func (win *winBot) isOpen() bool {
 }
 
 // start bot session will effectively end a bot session if feedback channels are nil
-func (win *winBot) startBotSession(feedback bots.Feedback) {
+func (win *winBot) startBotSession(feedback *bots.Feedback) {
 	win.feedback = feedback
 
 	gl.BindTexture(gl.TEXTURE_2D, win.obsTexture)
@@ -78,18 +78,19 @@ func (win *winBot) startBotSession(feedback bots.Feedback) {
 
 // do not open if no bot is defined
 func (win *winBot) setOpen(open bool) {
-	if win.feedback.Diagnostic == nil || win.feedback.Images == nil {
+	if win.feedback == nil {
+		win.open = false
 		return
 	}
-
 	win.open = open
-
-	if win.open {
-		// clear texture
-	}
 }
 
 func (win *winBot) draw() {
+	// no bot feedback instance
+	if win.feedback == nil {
+		return
+	}
+
 	// receive new thumbnail data and copy to texture
 	select {
 	case img := <-win.feedback.Images: