feat: Sprint 5 — xterm.js terminal with WebSocket mock shell, Alpine tab management

app/backend/internal/handler/terminal.go

@@ -0,0 +1,131 @@
+package handler
+
+import (
+	"fmt"
+	"log"
+	"strings"
+	"time"
+
+	"github.com/gofiber/contrib/websocket"
+	"github.com/gofiber/fiber/v2"
+)
+
+func Terminal(c *fiber.Ctx) error {
+	return c.Render("terminal", fiber.Map{
+		"View":     "terminal",
+		"Title":    "Terminal",
+		"NavItems": navItems,
+	})
+}
+
+var hostList = []struct {
+	ID   string
+	Name string
+	IP   string
+}{
+	{"h1", "api-prod-01", "10.0.1.15"},
+	{"h2", "db-primary-01", "10.0.2.5"},
+	{"h6", "monitor-01", "10.0.0.5"},
+	{"h7", "worker-pool-01", "10.0.4.50"},
+}
+
+func TerminalWS(c *websocket.Conn) {
+	host := c.Params("host", "unknown")
+	log.Printf("WS connected: host=%s", host)
+
+	welcome := fmt.Sprintf("\x1b[1;32mWelcome to %s\x1b[0m\r\n\x1b[2mConnected at %s\x1b[0m\r\n\r\n", host, time.Now().Format(time.RFC822))
+	c.WriteMessage(websocket.TextMessage, []byte(welcome))
+
+	prompt := fmt.Sprintf("\x1b[1;34m%s:~$\x1b[0m ", host)
+	cwd := "~"
+
+	buf := ""
+	for {
+		_, msg, err := c.ReadMessage()
+		if err != nil {
+			break
+		}
+
+		input := string(msg)
+
+		switch {
+		case input == "\r":
+			output := handleCommand(buf, host, &cwd)
+			c.WriteMessage(websocket.TextMessage, []byte(output+prompt))
+			buf = ""
+		case input == "\x7f":
+			if len(buf) > 0 {
+				buf = buf[:len(buf)-1]
+				c.WriteMessage(websocket.TextMessage, []byte("\b \b"))
+			}
+		case input == "\x03":
+			buf = ""
+			c.WriteMessage(websocket.TextMessage, []byte("^C\r\n"+prompt))
+		default:
+			if input >= " " && input <= "~" {
+				buf += input
+				c.WriteMessage(websocket.TextMessage, []byte(input))
+			}
+		}
+	}
+	log.Printf("WS disconnected: host=%s", host)
+}
+
+func handleCommand(cmd, host string, cwd *string) string {
+	cmd = strings.TrimSpace(cmd)
+	if cmd == "" {
+		return ""
+	}
+
+	parts := strings.Fields(cmd)
+	if len(parts) == 0 {
+		return ""
+	}
+
+	switch parts[0] {
+	case "clear":
+		return "\x1b[2J\x1b[H"
+	case "exit", "logout":
+		return "logout\r\n\x1b[2J\x1b[H\x1b[1;31mConnection closed.\x1b[0m\r\n"
+	case "pwd":
+		return *cwd + "\r\n"
+	case "whoami":
+		return "deploy\r\n"
+	case "hostname":
+		return host + "\r\n"
+	case "date":
+		return time.Now().Format("Mon Jan 2 15:04:05 MST 2006") + "\r\n"
+	case "uptime":
+		return fmt.Sprintf(" 13:42:17 up %d day,  1 user,  load average: 0.08, 0.12, 0.10\r\n", 1+time.Now().Day()%30)
+	case "uname":
+		if len(parts) > 1 && parts[1] == "-a" {
+			return fmt.Sprintf("Linux %s 6.8.0-45-generic #47-Ubuntu SMP PREEMPT x86_64 x86_64 x86_64 GNU/Linux\r\n", host)
+		}
+		return "Linux\r\n"
+	case "ls":
+		if *cwd == "~" || *cwd == "/home/deploy" {
+			return "Documents  Downloads  projects  config.yml  README.md  .env\r\n"
+		}
+		return "total 0\r\n"
+	case "cd":
+		if len(parts) > 1 {
+			*cwd = parts[1]
+		} else {
+			*cwd = "~"
+		}
+		return ""
+	case "cat":
+		if len(parts) > 1 {
+			return fmt.Sprintf("\x1b[1;37m# Content of %s\x1b[0m\r\n(not implemented in mock shell)\r\n", parts[1])
+		}
+		return ""
+	case "echo":
+		return strings.Join(parts[1:], " ") + "\r\n"
+	case "ssh":
+		return "\x1b[1;33mSSH forwarding not available in mock mode\x1b[0m\r\n"
+	case "help":
+		return "Available commands: clear, exit, pwd, whoami, hostname, date, uptime, uname, ls, cd, cat, echo, ssh, help\r\n"
+	default:
+		return fmt.Sprintf("\x1b[1;31m%s: command not found\x1b[0m\r\n", parts[0])
+	}
+}