More work on shell

tools/cmd/at/shell.go

@@ -3,7 +3,13 @@
 package at
 
 import (
+	"errors"
 	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"github.com/google/shlex"
 
 	"kitty/tools/cli"
 	"kitty/tools/cli/markup"
@@ -17,17 +23,20 @@ var formatter *markup.Context
 
 const prompt = "🐱 "
 
-func shell_loop(kill_if_signaled bool) (int, error) {
+var ErrExec = errors.New("Execute command")
+
+func shell_loop(rl *readline.Readline, kill_if_signaled bool) (int, error) {
 	lp, err := loop.New(loop.NoAlternateScreen, loop.NoRestoreColors)
 	if err != nil {
 		return 1, err
 	}
-	rl := readline.New(lp, readline.RlInit{Prompt: prompt})
+	rl.ChangeLoopAndResetText(lp)
 
 	lp.OnInitialize = func() (string, error) {
 		rl.Start()
-		return "\r\n", nil
+		return "", nil
 	}
+	lp.OnFinalize = func() string { rl.End(); return "" }
 
 	lp.OnResumeFromStop = func() error {
 		rl.Start()
@@ -42,6 +51,17 @@ func shell_loop(kill_if_signaled bool) (int, error) {
 	lp.OnKeyEvent = func(event *loop.KeyEvent) error {
 		err := rl.OnKeyEvent(event)
 		if err != nil {
+			if err == io.EOF {
+				lp.Quit(0)
+				return nil
+			}
+			if err == readline.ErrAcceptInput {
+				if strings.HasSuffix(rl.TextBeforeCursor(), "\\") && strings.HasPrefix(rl.TextAfterCursor(), "\n") {
+					rl.OnText("\n", false, false)
+					return nil
+				}
+				return ErrExec
+			}
 			return err
 		}
 		if event.Handled {
@@ -67,9 +87,39 @@ func shell_loop(kill_if_signaled bool) (int, error) {
 	return 0, nil
 }
 
+func exec_command(cmdline string) bool {
+	parsed_cmdline, err := shlex.Split(cmdline)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, "Could not parse cmdline:", err)
+		return true
+	}
+	if len(parsed_cmdline) == 0 {
+		return true
+	}
+	switch parsed_cmdline[0] {
+	case "exit":
+		return false
+	}
+	return true
+}
+
 func shell_main(cmd *cli.Command, args []string) (int, error) {
 	formatter = markup.New(true)
 	fmt.Println("Welcome to the kitty shell!")
 	fmt.Println("Use", formatter.Green("help"), "for assistance or", formatter.Green("exit"), "to quit.")
-	return shell_loop(true)
+	rl := readline.New(nil, readline.RlInit{Prompt: prompt})
+	for {
+		rc, err := shell_loop(rl, true)
+		if err != nil {
+			if err == ErrExec {
+				cmdline := rl.AllText()
+				cmdline = strings.ReplaceAll(cmdline, "\\\n", "")
+				if !exec_command(cmdline) {
+					return 0, nil
+				}
+				continue
+			}
+		}
+		return rc, err
+	}
 }

tools/tui/loop/api.go

@@ -53,6 +53,10 @@ type Loop struct {
 	// the terminal on shutdown
 	OnInitialize func() (string, error)
 
+	// Called just before the loop shuts down. Any returned string is written to the terminal before
+	// shutdown
+	OnFinalize func() string
+
 	// Called when a key event happens
 	OnKeyEvent func(event *KeyEvent) error
 

tools/tui/readline/actions.go

@@ -4,6 +4,7 @@ package readline
 
 import (
 	"fmt"
+	"io"
 	"strings"
 
 	"kitty/tools/utils"
@@ -259,24 +260,52 @@ func (self *Readline) erase_chars_after_cursor(amt uint, traverse_line_breaks bo
 	return num
 }
 
-func (self *Readline) perform_action(ac Action, repeat_count uint) bool {
+func (self *Readline) next_word_char_pos(traverse_line_breaks bool) int {
+	return 0
+}
+
+func (self *Readline) perform_action(ac Action, repeat_count uint) error {
 	switch ac {
 	case ActionBackspace:
-		return self.erase_chars_before_cursor(repeat_count, true) > 0
+		if self.erase_chars_before_cursor(repeat_count, true) > 0 {
+			return nil
+		}
 	case ActionDelete:
-		return self.erase_chars_after_cursor(repeat_count, true) > 0
+		if self.erase_chars_after_cursor(repeat_count, true) > 0 {
+			return nil
+		}
 	case ActionMoveToStartOfLine:
-		return self.move_to_start_of_line()
+		if self.move_to_start_of_line() {
+			return nil
+		}
 	case ActionMoveToEndOfLine:
-		return self.move_to_end_of_line()
+		if self.move_to_end_of_line() {
+			return nil
+		}
 	case ActionMoveToStartOfDocument:
-		return self.move_to_start()
+		if self.move_to_start() {
+			return nil
+		}
 	case ActionMoveToEndOfDocument:
-		return self.move_to_end()
+		if self.move_to_end() {
+			return nil
+		}
 	case ActionCursorLeft:
-		return self.move_cursor_left(repeat_count, true) > 0
+		if self.move_cursor_left(repeat_count, true) > 0 {
+			return nil
+		}
 	case ActionCursorRight:
-		return self.move_cursor_right(repeat_count, true) > 0
+		if self.move_cursor_right(repeat_count, true) > 0 {
+			return nil
+		}
+	case ActionEndInput:
+		line := self.lines[self.cursor.Y]
+		if line == "" {
+			return io.EOF
+		}
+		return self.perform_action(ActionAcceptInput, 1)
+	case ActionAcceptInput:
+		return ErrAcceptInput
 	}
-	return false
+	return ErrCouldNotPerformAction
 }

tools/tui/readline/api.go

@@ -42,6 +42,8 @@ const (
 	ActionMoveToEndOfDocument
 	ActionCursorLeft
 	ActionCursorRight
+	ActionEndInput
+	ActionAcceptInput
 )
 
 type Readline struct {
@@ -78,12 +80,32 @@ func New(loop *loop.Loop, r RlInit) *Readline {
 	return ans
 }
 
+func (self *Readline) ChangeLoopAndResetText(lp *loop.Loop) {
+	self.loop = lp
+	self.lines = []string{""}
+	self.cursor = Position{}
+	self.cursor_y = 0
+}
+
 func (self *Readline) Start() {
 	self.loop.SetCursorShape(loop.BAR_CURSOR, true)
 	self.loop.StartBracketedPaste()
 	self.Redraw()
 }
 
+func (self *Readline) End() {
+	self.loop.SetCursorShape(loop.BLOCK_CURSOR, true)
+	self.loop.EndBracketedPaste()
+	self.loop.QueueWriteString("\r\n")
+	if self.mark_prompts {
+		self.loop.QueueWriteString(PROMPT_MARK + "C" + ST)
+	}
+}
+
+func MarkOutputStart() string {
+	return PROMPT_MARK + "C" + ST
+}
+
 func (self *Readline) Redraw() {
 	self.loop.StartAtomicUpdate()
 	self.RedrawNonAtomic()
@@ -94,15 +116,6 @@ func (self *Readline) RedrawNonAtomic() {
 	self.redraw()
 }
 
-func (self *Readline) End() {
-	self.loop.EndBracketedPaste()
-	self.loop.QueueWriteString("\r\n")
-	self.loop.SetCursorShape(loop.BLOCK_CURSOR, true)
-	if self.mark_prompts {
-		self.loop.QueueWriteString(PROMPT_MARK + "C" + ST)
-	}
-}
-
 func (self *Readline) OnKeyEvent(event *loop.KeyEvent) error {
 	err := self.handle_key_event(event)
 	if err == ErrCouldNotPerformAction {
@@ -117,6 +130,14 @@ func (self *Readline) OnText(text string, from_key_event bool, in_bracketed_past
 	return nil
 }
 
-func (self *Readline) PerformAction(ac Action, repeat_count uint) bool {
-	return self.perform_action(ac, repeat_count)
+func (self *Readline) TextBeforeCursor() string {
+	return self.text_upto_cursor_pos()
+}
+
+func (self *Readline) TextAfterCursor() string {
+	return self.text_after_cursor_pos()
+}
+
+func (self *Readline) AllText() string {
+	return self.all_text()
 }

tools/tui/readline/keys.go

@@ -15,7 +15,6 @@ var default_shortcuts = map[string]Action{
 	"backspace": ActionBackspace,
 	"ctrl+h":    ActionBackspace,
 	"delete":    ActionDelete,
-	"ctrl+d":    ActionDelete,
 
 	"home":   ActionMoveToStartOfLine,
 	"ctrl+a": ActionMoveToStartOfLine,
@@ -30,6 +29,9 @@ var default_shortcuts = map[string]Action{
 	"ctrl+b": ActionCursorLeft,
 	"right":  ActionCursorRight,
 	"ctrl+f": ActionCursorRight,
+
+	"ctrl+d": ActionEndInput,
+	"enter":  ActionAcceptInput,
 }
 
 func action_for_key_event(event *loop.KeyEvent, shortcuts map[string]Action) Action {
@@ -42,6 +44,7 @@ func action_for_key_event(event *loop.KeyEvent, shortcuts map[string]Action) Act
 }
 
 var ErrCouldNotPerformAction = errors.New("Could not perform the specified action")
+var ErrAcceptInput = errors.New("Accept input")
 
 func (self *Readline) handle_key_event(event *loop.KeyEvent) error {
 	if event.Text != "" {
@@ -50,9 +53,7 @@ func (self *Readline) handle_key_event(event *loop.KeyEvent) error {
 	ac := action_for_key_event(event, default_shortcuts)
 	if ac != ActionNil {
 		event.Handled = true
-		if !self.perform_action(ac, 1) {
-			return ErrCouldNotPerformAction
-		}
+		return self.perform_action(ac, 1)
 	}
 	return nil
 }