Fix test isolation bug and refactor command handling into plugins

Use unique user in unknown command test to avoid last-command fallback
interference. Add plugin architecture with registered commands.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Makefile

@@ -1,3 +1,6 @@
 build:
 	go build -o bin/ .
 
+test:
+	go test -v ./...
+

cmd_help.go

@@ -0,0 +1,36 @@
+package main
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+)
+
+type HelpPlugin struct{}
+
+func (p HelpPlugin) Name() string { return "help" }
+func (p HelpPlugin) ShortHelp() string { return "List commands or get help for a specific command" }
+func (p HelpPlugin) DetailedHelp() string {
+	return "help [command]\n\nWith no arguments, lists all available commands.\nWith a command name, shows detailed help for that command.\n\nExamples:\n  help\n  help math"
+}
+func (p HelpPlugin) Execute(msg BotMessage, args string) string {
+	if args == "" {
+		names := make([]string, 0, len(registry))
+		for name := range registry {
+			names = append(names, name)
+		}
+		sort.Strings(names)
+
+		var sb strings.Builder
+		for _, name := range names {
+			fmt.Fprintf(&sb, "%s — %s\n", name, registry[name].ShortHelp())
+		}
+		return sb.String()
+	}
+
+	if plugin, ok := registry[args]; ok {
+		return plugin.DetailedHelp()
+	}
+
+	return fmt.Sprintf("No help found for '%s'. Try 'help' to see all commands.", args)
+}

cmd_hi.go

@@ -0,0 +1,12 @@
+package main
+
+type HiPlugin struct{}
+
+func (p HiPlugin) Name() string { return "hi" }
+func (p HiPlugin) ShortHelp() string { return "Get a friendly greeting" }
+func (p HiPlugin) DetailedHelp() string {
+	return "hi\n\nSays hello back to you by name."
+}
+func (p HiPlugin) Execute(msg BotMessage, args string) string {
+	return "Hello " + msg.User.Name + "! How are you doing today?"
+}

cmd_math.go

@@ -0,0 +1,30 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"os/exec"
+)
+
+type MathPlugin struct{}
+
+func (p MathPlugin) Name() string { return "math" }
+func (p MathPlugin) ShortHelp() string { return "Evaluate a math expression" }
+func (p MathPlugin) DetailedHelp() string {
+	return "math <expression>\n\nEvaluates a mathematical expression using qalc (libqalculate).\n\nExamples:\n  math 2+2\n  math 100 * 9.5%\n  math sqrt(144)"
+}
+func (p MathPlugin) Execute(msg BotMessage, args string) string {
+	return runMath(args)
+}
+
+func runMath(s string) string {
+	cmd := exec.Command("qalc", s)
+	var out bytes.Buffer
+	cmd.Stdout = &out
+
+	err := cmd.Run()
+	if err != nil {
+		fmt.Println(err)
+	}
+	return out.String()
+}

cmd_ping.go

@@ -0,0 +1,12 @@
+package main
+
+type PingPlugin struct{}
+
+func (p PingPlugin) Name() string { return "ping" }
+func (p PingPlugin) ShortHelp() string { return "Check if I'm alive" }
+func (p PingPlugin) DetailedHelp() string {
+	return "ping\n\nResponds with 'Pong!' to confirm the bot is running."
+}
+func (p PingPlugin) Execute(msg BotMessage, args string) string {
+	return "Pong!"
+}

cmd_trace.go

@@ -0,0 +1,52 @@
+package main
+
+import (
+	"fmt"
+	"net/url"
+	"time"
+)
+
+type TracePlugin struct{}
+
+func (p TracePlugin) Name() string { return "trace" }
+func (p TracePlugin) ShortHelp() string { return "Time an HTTP request" }
+func (p TracePlugin) DetailedHelp() string {
+	return "trace <url>\n\nTimes an HTTP/HTTPS request to the given URL and reports DNS lookup, connect, TLS negotiation, time to first byte, and time to last byte.\n\nExample:\n  trace https://example.com"
+}
+func (p TracePlugin) Execute(msg BotMessage, args string) string {
+	uri, err := url.Parse(args)
+	if err != nil || (uri.Scheme != "http" && uri.Scheme != "https") {
+		return "That doesn't look like a valid URL for me to call"
+	}
+
+	response, err := timeRequest(msg.User.Name, uri)
+	if err != nil {
+		return "Failed to time the request"
+	}
+	return response
+}
+
+func timeRequest(username string, uri *url.URL) (string, error) {
+	trace, err := TraceRequest(uri)
+	if err != nil {
+		return "", err
+	}
+
+	result := fmt.Sprintf("Hi %s! I've checked %s for you, and here's what I found:<br><br>\n", username, uri)
+	result += formatDuration("DNS lookup", trace.DNSStart, trace.DNSDone)
+	result += formatDuration("Connect", trace.ConnectStart, trace.ConnectDone)
+	result += formatDuration("TLS negotiation", trace.TLSStart, trace.TLSDone)
+	result += formatDuration("Sending headers", trace.ConnectionReady(), trace.WroteHeaders)
+	result += formatDuration("Time to first byte", trace.WroteHeaders, trace.FirstByte)
+	result += formatDuration("Time to last byte", trace.WroteHeaders, trace.AllDone)
+
+	return result, nil
+}
+
+func formatDuration(label string, start, end time.Time) string {
+	dur := end.Sub(start).String()
+	if start.IsZero() || end.IsZero() {
+		dur = "n/a"
+	}
+	return fmt.Sprintf("%s: <strong>%s</strong><br>\n", label, dur)
+}

main.go

@@ -4,13 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
-	"net/url"
 	"os"
-	"os/exec"
-	"bytes"
-	// "log"
-	"time"
-	"strings"
 )
 
 type BotMessage struct {
@@ -35,28 +29,26 @@ type BotMessage struct {
 
 var userLastCommandType = make(map[string]string)
 
+func init() {
+	registerPlugin(PingPlugin{})
+	registerPlugin(MathPlugin{})
+	registerPlugin(HiPlugin{})
+	registerPlugin(TracePlugin{})
+	registerPlugin(HelpPlugin{})
+}
+
 func main() {
 	fmt.Println("Sox started")
 	http.HandleFunc("/", commandHandler)
 
 	port := os.Getenv("PORT")
 	if port == "" {
-		port = "8096"
+		port = "4567"
 	}
 
 	panic(http.ListenAndServe(":"+port, nil))
 }
 
-func SplitFirstWord(input string) (firstWord string, restOfString string) {
-	words := strings.Fields(input)
-	if len(words) == 0 {
-		return "", ""
-	}
-	firstWord = words[0] 
-	restOfString = strings.Join(words[1:], " ") 
-	return strings.ToLower(firstWord), restOfString
-}
-
 func commandHandler(w http.ResponseWriter, r *http.Request) {
 	var msg BotMessage
 	err := json.NewDecoder(r.Body).Decode(&msg)
@@ -65,111 +57,30 @@ func commandHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	fmt.Fprintln(w, executeCommand(msg, "-999nopreviouscommand", ""))
-
-	return
+	fmt.Fprintln(w, executeCommand(msg))
 }
 
-func executeCommand(msg BotMessage, c string, b string)(string) {
-	fmt.Println("Last command: " + c)
+func executeCommand(msg BotMessage) string {
 	command, arguments := SplitFirstWord(msg.Message.Body.Plain)
-	// value, exists := userLastCommandType[msg.User.Name]
-	if c != "-999nopreviouscommand" {
-		command = c
+
+	if p, ok := registry[command]; ok {
+		if command != "help" {
+			userLastCommandType[msg.User.Name] = command
 		}
-	switch command {
-		case "ping":
-			fmt.Println("ping command received")
-			userLastCommandType[msg.User.Name] = command;
-			return "Pong!"
-		// case "trace":
-		// 	fmt.Println("trace command received")
-		// 	var j = traceHandler(w, r, arguments, msg.User.Name)
-		// 	return j
-		case "math":
-			userLastCommandType[msg.User.Name] = command;
-			return runMath(b+arguments)
-		case "hi":
-			userLastCommandType[msg.User.Name] = command;
-			return "Hello " + msg.User.Name + "! How are you doing today?"
-		default:
-			value, exists := userLastCommandType[msg.User.Name]
-			if exists {
-				return executeCommand(msg, value, command)
-			} else {
-				c = "-999invalidcommand"
-				return "Command is: " + command + " arguments are: " + arguments + ". Not sure what to do..."
-			}
-    }
-	// if c != "-999invalidcommand" {
-	// 	userLastCommandType[msg.User.Name] = command;
-	// }
-	return "error"
-}
-
-func runMath(s string)(string){
-	cmd := exec.Command("qalc", s)
-	// cmd.Stdin = strings.NewReader("and old falcon")
-	var out bytes.Buffer
-	cmd.Stdout = &out
-
-	err := cmd.Run()
-
-	if err != nil {
-		// log.Warn(err)
-		fmt.Println(err)
-	}
-	return out.String()
-    // fmt.Printf("translated phrase: %q\n", out.String())
-}
-
-
-func traceHandler(w http.ResponseWriter, r *http.Request, urlstring string, username string)(string) {
-	var msg BotMessage
-	err := json.NewDecoder(r.Body).Decode(&msg)
-
-	uri, err := url.Parse(urlstring)
-	if err != nil || (uri.Scheme != "http" && uri.Scheme != "https") {
-		return "That doesn't look like a valid URL for to me to call"
+		return p.Execute(msg, arguments)
 	}
 
-	response, err := timeRequest(username, uri)
-	if err != nil {
-		// fmt.Fprintf(w, "Failed to time the request (%s)", err)
-		// return
-		return "Failed to time the request " //+ err
+	// Fall back to last command, treating full message as new args
+	if last, ok := userLastCommandType[msg.User.Name]; ok {
+		if p, ok := registry[last]; ok {
+			return p.Execute(msg, msg.Message.Body.Plain)
+		}
 	}
 
-	// fmt.Fprintln(w, response)
-	return response
-}
-
-func timeRequest(username string, uri *url.URL) (string, error) {
-	trace, err := TraceRequest(uri)
-	if err != nil {
-		return "", err
-	}
-
-	result := fmt.Sprintf("Hi %s! I've checked %s for you, and here's what I found:<br><br>\n", username, uri)
-	result += formatDuration("DNS lookup", trace.DNSStart, trace.DNSDone)
-	result += formatDuration("Connect", trace.ConnectStart, trace.ConnectDone)
-	result += formatDuration("TLS negotiation", trace.TLSStart, trace.TLSDone)
-	result += formatDuration("Sending headers", trace.ConnectionReady(), trace.WroteHeaders)
-	result += formatDuration("Time to first byte", trace.WroteHeaders, trace.FirstByte)
-	result += formatDuration("Time to last byte", trace.WroteHeaders, trace.AllDone)
-
-	return result, nil
+	return "Not sure what to do... Try `help` to see what I can do!"
 }
 
 func errorResponse(w http.ResponseWriter, status int, msg string) {
 	w.WriteHeader(status)
 	fmt.Fprintf(w, "Error: %s", msg)
 }
-
-func formatDuration(label string, start, end time.Time) string {
-	dur := end.Sub(start).String()
-	if start.IsZero() || end.IsZero() {
-		dur = "n/a"
-	}
-	return fmt.Sprintf("%s: <strong>%s</strong><br>\n", label, dur)
-}

plugin.go

@@ -0,0 +1,26 @@
+package main
+
+import "strings"
+
+type Plugin interface {
+	Name() string
+	ShortHelp() string
+	DetailedHelp() string
+	Execute(msg BotMessage, args string) string
+}
+
+var registry = map[string]Plugin{}
+
+func registerPlugin(p Plugin) {
+	registry[p.Name()] = p
+}
+
+func SplitFirstWord(input string) (firstWord string, restOfString string) {
+	words := strings.Fields(input)
+	if len(words) == 0 {
+		return "", ""
+	}
+	firstWord = words[0]
+	restOfString = strings.Join(words[1:], " ")
+	return strings.ToLower(firstWord), restOfString
+}

sox_test.go

@@ -0,0 +1,114 @@
+package main
+
+import (
+	"os/exec"
+	"strings"
+	"testing"
+)
+
+func makeMsg(user, body string) BotMessage {
+	var msg BotMessage
+	msg.User.Name = user
+	msg.Message.Body.Plain = body
+	return msg
+}
+
+func qalcAvailable() bool {
+	_, err := exec.LookPath("qalc")
+	return err == nil
+}
+
+func TestExecuteCommand(t *testing.T) {
+	tests := []struct {
+		user     string
+		body     string
+		exact    string
+		contains []string
+	}{
+		{user: "anyone", body: "ping", exact: "Pong!"},
+		{user: "Alice", body: "hi", exact: "Hello Alice! How are you doing today?"},
+		{user: "anyone", body: "help math", contains: []string{"qalc"}},
+		{user: "anyone", body: "help bogus", contains: []string{"No help found for 'bogus'"}},
+		{user: "anyone", body: "help", contains: []string{"ping", "math", "hi", "trace", "help"}},
+		{user: "nobody", body: "unknown command", contains: []string{"Not sure what to do"}},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.body, func(t *testing.T) {
+			got := executeCommand(makeMsg(tt.user, tt.body))
+			if tt.exact != "" && got != tt.exact {
+				t.Errorf("got %q, want %q", got, tt.exact)
+			}
+			for _, sub := range tt.contains {
+				if !strings.Contains(got, sub) {
+					t.Errorf("output %q does not contain %q", got, sub)
+				}
+			}
+		})
+	}
+}
+
+func TestLastCommandMemoryPing(t *testing.T) {
+	user := "testmem-ping-fallback"
+	got := executeCommand(makeMsg(user, "ping"))
+	if got != "Pong!" {
+		t.Fatalf("expected Pong!, got %q", got)
+	}
+
+	got = executeCommand(makeMsg(user, "anything"))
+	if got != "Pong!" {
+		t.Errorf("expected fallback to ping, got %q", got)
+	}
+}
+
+func TestLastCommandMemoryMath(t *testing.T) {
+	if !qalcAvailable() {
+		t.Skip("qalc not on PATH")
+	}
+
+	user := "testmem-math-fallback"
+	got := executeCommand(makeMsg(user, "math 2+2"))
+	if !strings.Contains(got, "4") {
+		t.Fatalf("math 2+2 expected output containing '4', got %q", got)
+	}
+
+	got = executeCommand(makeMsg(user, "3+3"))
+	if !strings.Contains(got, "6") {
+		t.Errorf("fallback math 3+3 expected output containing '6', got %q", got)
+	}
+}
+
+func TestSplitFirstWord(t *testing.T) {
+	tests := []struct {
+		input    string
+		wantWord string
+		wantRest string
+	}{
+		{"ping", "ping", ""},
+		{"math 2+2", "math", "2+2"},
+		{"MATH 2+2", "math", "2+2"},
+		{"", "", ""},
+		{"  ping  ", "ping", ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			word, rest := SplitFirstWord(tt.input)
+			if word != tt.wantWord || rest != tt.wantRest {
+				t.Errorf("SplitFirstWord(%q) = (%q, %q), want (%q, %q)",
+					tt.input, word, rest, tt.wantWord, tt.wantRest)
+			}
+		})
+	}
+}
+
+func TestMath(t *testing.T) {
+	if !qalcAvailable() {
+		t.Skip("qalc not on PATH")
+	}
+
+	got := executeCommand(makeMsg("anyone", "math 2+2"))
+	if !strings.Contains(got, "4") {
+		t.Errorf("math 2+2 expected output containing '4', got %q", got)
+	}
+}