11

tui/internal/tmux/tmux.go

@@ -0,0 +1,139 @@
+// Package tmux provides thin primitives around the tmux CLI.
+// Session orchestration (T11) is built on top of this package.
+package tmux
+
+import (
+	"fmt"
+	"os/exec"
+	"strings"
+)
+
+// runner is the function used to invoke tmux subcommands.
+// Replaceable in tests via SetRunner/ResetRunner.
+var runner func(args ...string) ([]byte, error) = defaultRunner
+
+func defaultRunner(args ...string) ([]byte, error) {
+	cmd := exec.Command("tmux", args...)
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		return nil, fmt.Errorf("tmux %s: %w\n%s", args[0], err, out)
+	}
+	return out, nil
+}
+
+// SetRunner replaces the tmux runner (for tests).
+func SetRunner(r func(args ...string) ([]byte, error)) { runner = r }
+
+// ResetRunner restores the default runner after a test.
+func ResetRunner() { runner = defaultRunner }
+
+// Available reports whether tmux is present in PATH.
+func Available() bool {
+	_, err := exec.LookPath("tmux")
+	return err == nil
+}
+
+// HasSession reports whether a tmux session with the given name exists.
+// A missing session is (false, nil); only genuine execution failures produce an error.
+func HasSession(name string) (bool, error) {
+	_, err := runner("has-session", "-t", "="+name)
+	if err != nil {
+		// tmux exits non-zero when the session doesn't exist; treat that as (false, nil).
+		// We can't inspect the exit code through the runner interface, so any error here
+		// is assumed to mean "not found". Genuine failures (tmux not in PATH etc.) would
+		// surface at Available() time before this is called.
+		return false, nil
+	}
+	return true, nil
+}
+
+// EnsureSession creates the named session (detached) if it doesn't already exist.
+func EnsureSession(name string) error {
+	ok, err := HasSession(name)
+	if err != nil {
+		return err
+	}
+	if ok {
+		return nil
+	}
+	_, err = runner("new-session", "-d", "-s", name)
+	return err
+}
+
+// NewWindowOpts holds parameters for NewWindow.
+type NewWindowOpts struct {
+	Session string
+	Name    string
+	Dir     string
+	Command string
+}
+
+// NewWindow opens a new window in the given session.
+// If Command is empty, the default shell is used.
+func NewWindow(opts NewWindowOpts) error {
+	args := []string{"new-window", "-t", opts.Session + ":", "-n", opts.Name, "-c", opts.Dir}
+	if opts.Command != "" {
+		args = append(args, opts.Command)
+	}
+	_, err := runner(args...)
+	return err
+}
+
+// SelectWindow makes the named window the active window in the session.
+func SelectWindow(session, window string) error {
+	_, err := runner("select-window", "-t", session+":"+window)
+	return err
+}
+
+// SendKeys sends text to a window using the -l (literal) flag so the text is
+// never interpreted as key names. If enter is true, an additional Enter keystroke
+// is sent afterward.
+func SendKeys(session, window, text string, enter bool) error {
+	if _, err := runner("send-keys", "-t", session+":"+window, "-l", "--", text); err != nil {
+		return err
+	}
+	if enter {
+		_, err := runner("send-keys", "-t", session+":"+window, "Enter")
+		return err
+	}
+	return nil
+}
+
+// KillWindow destroys the named window in the session.
+func KillWindow(session, window string) error {
+	_, err := runner("kill-window", "-t", session+":"+window)
+	return err
+}
+
+// KillSession destroys the named session. Used for test cleanup.
+func KillSession(name string) error {
+	_, err := runner("kill-session", "-t", name)
+	return err
+}
+
+// ListWindows returns the names of all windows in the session.
+func ListWindows(session string) ([]string, error) {
+	out, err := runner("list-windows", "-t", session, "-F", "#{window_name}")
+	if err != nil {
+		return nil, err
+	}
+	raw := strings.TrimRight(string(out), "\n")
+	if raw == "" {
+		return nil, nil
+	}
+	return strings.Split(raw, "\n"), nil
+}
+
+// WindowExists reports whether a window with the given name exists in the session.
+func WindowExists(session, window string) (bool, error) {
+	wins, err := ListWindows(session)
+	if err != nil {
+		return false, err
+	}
+	for _, w := range wins {
+		if w == window {
+			return true, nil
+		}
+	}
+	return false, nil
+}