Improve tab completion system

5 files changed, 154 insertions, 57 deletions

diff --git a/interface/ui.go b/interface/ui.go
index cdd1927..83fa7da 100644
--- a/interface/ui.go
+++ b/interface/ui.go
@@ -77,7 +77,7 @@ type RoomView interface {
 	SaveHistory(dir string) error
 	LoadHistory(matrix MatrixContainer, dir string) (int, error)
 
-	SetStatus(status string)
+	SetCompletions(completions []string)
 	SetTyping(users []string)
 	UpdateUserList()
 
diff --git a/lib/util/lcp.go b/lib/util/lcp.go
new file mode 100644
index 0000000..2e2e690
--- /dev/null
+++ b/lib/util/lcp.go
@@ -0,0 +1,38 @@
+// Licensed under the GNU Free Documentation License 1.2
+// https://www.gnu.org/licenses/old-licenses/fdl-1.2.en.html
+//
+// Source: https://rosettacode.org/wiki/Longest_common_prefix#Go
+
+package util
+
+func LongestCommonPrefix(list []string) string {
+	// Special cases first
+	switch len(list) {
+	case 0:
+		return ""
+	case 1:
+		return list[0]
+	}
+
+	// LCP of min and max (lexigraphically)
+	// is the LCP of the whole set.
+	min, max := list[0], list[0]
+	for _, s := range list[1:] {
+		switch {
+		case s < min:
+			min = s
+		case s > max:
+			max = s
+		}
+	}
+
+	for i := 0; i < len(min) && i < len(max); i++ {
+		if min[i] != max[i] {
+			return min[:i]
+		}
+	}
+
+	// In the case where lengths are not equal but all bytes
+	// are equal, min is the answer ("foo" < "foobar").
+	return min
+}
diff --git a/ui/room-view.go b/ui/room-view.go
index 5268682..332605b 100644
--- a/ui/room-view.go
+++ b/ui/room-view.go
@@ -19,11 +19,14 @@ package ui
 import (
 	"fmt"
 	"path/filepath"
+	"sort"
 	"strconv"
 	"strings"
 	"time"
 
+	"github.com/mattn/go-runewidth"
 	"maunium.net/go/gomuks/interface"
+	"maunium.net/go/gomuks/lib/util"
 	"maunium.net/go/gomuks/matrix/rooms"
 	"maunium.net/go/gomuks/ui/messages"
 	"maunium.net/go/gomuks/ui/widget"
@@ -41,6 +44,13 @@ type RoomView struct {
 	ulBorder *widget.Border
 	input    *widget.AdvancedInputField
 	Room     *rooms.Room
+
+	typing []string
+	completions struct {
+		list      []string
+		textCache string
+		time      time.Time
+	}
 }
 
 func NewRoomView(room *rooms.Room) *RoomView {
@@ -58,7 +68,8 @@ func NewRoomView(room *rooms.Room) *RoomView {
 	view.input.
 		SetFieldBackgroundColor(tcell.ColorDefault).
 		SetPlaceholder("Send a message...").
-		SetPlaceholderExtColor(tcell.ColorGray)
+		SetPlaceholderExtColor(tcell.ColorGray).
+		SetTabCompleteFunc(view.InputTabComplete)
 
 	view.topic.
 		SetText(strings.Replace(room.GetTopic(), "\n", " ", -1)).
@@ -85,13 +96,6 @@ func (view *RoomView) LoadHistory(matrix ifc.MatrixContainer, dir string) (int,
 	return view.MessageView().LoadHistory(matrix, view.logPath(dir))
 }
 
-func (view *RoomView) SetTabCompleteFunc(fn func(room *RoomView, text string, cursorOffset int) string) *RoomView {
-	view.input.SetTabCompleteFunc(func(text string, cursorOffset int) string {
-		return fn(view, text, cursorOffset)
-	})
-	return view
-}
-
 func (view *RoomView) SetInputCapture(fn func(room *RoomView, event *tcell.EventKey) *tcell.EventKey) *RoomView {
 	view.input.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
 		return fn(view, event)
@@ -151,6 +155,30 @@ const (
 	StaticVerticalSpace = TopicBarHeight + StatusBarHeight + InputBarHeight
 )
 
+func (view *RoomView) GetStatus() string {
+	var buf strings.Builder
+
+	if len(view.completions.list) > 0 {
+		if view.completions.textCache != view.input.GetText() || view.completions.time.Add(10 * time.Second).Before(time.Now()) {
+			view.completions.list = []string{}
+		} else {
+			buf.WriteString(strings.Join(view.completions.list, ", "))
+			buf.WriteString(" - ")
+		}
+	}
+
+	if len(view.typing) == 1 {
+		buf.WriteString("Typing: " + view.typing[0])
+		buf.WriteString(" - ")
+	} else if len(view.typing) > 1 {
+		fmt.Fprintf(&buf,
+			"Typing: %s and %s - ",
+			strings.Join(view.typing[:len(view.typing)-1], ", "), view.typing[len(view.typing)-1])
+	}
+
+	return strings.TrimSuffix(buf.String(), " - ")
+}
+
 func (view *RoomView) Draw(screen tcell.Screen) {
 	x, y, width, height := view.GetInnerRect()
 	if width <= 0 || height <= 0 {
@@ -185,14 +213,17 @@ func (view *RoomView) Draw(screen tcell.Screen) {
 	view.Box.Draw(screen)
 	view.topic.Draw(screen)
 	view.content.Draw(screen)
+	view.status.SetText(view.GetStatus())
 	view.status.Draw(screen)
 	view.input.Draw(screen)
 	view.ulBorder.Draw(screen)
 	view.userList.Draw(screen)
 }
 
-func (view *RoomView) SetStatus(status string) {
-	view.status.SetText(status)
+func (view *RoomView) SetCompletions(completions []string) {
+	view.completions.list = completions
+	view.completions.textCache = view.input.GetText()
+	view.completions.time = time.Now()
 }
 
 func (view *RoomView) SetTyping(users []string) {
@@ -202,31 +233,74 @@ func (view *RoomView) SetTyping(users []string) {
 			users[index] = member.DisplayName
 		}
 	}
-	if len(users) == 0 {
-		view.status.SetText("")
-	} else if len(users) < 2 {
-		view.status.SetText("Typing: " + strings.Join(users, " and "))
-	} else {
-		view.status.SetText(fmt.Sprintf(
-			"Typing: %s and %s",
-			strings.Join(users[:len(users)-1], ", "), users[len(users)-1]))
-	}
+	view.typing = users
+}
+
+type completion struct {
+	displayName string
+	id          string
 }
 
-func (view *RoomView) AutocompleteUser(existingText string) (completions []*rooms.Member) {
+func (view *RoomView) AutocompleteUser(existingText string) (completions []completion) {
 	textWithoutPrefix := existingText
 	if strings.HasPrefix(existingText, "@") {
 		textWithoutPrefix = existingText[1:]
 	}
 	for _, user := range view.Room.GetMembers() {
-		if strings.HasPrefix(user.DisplayName, textWithoutPrefix) ||
-			strings.HasPrefix(user.UserID, existingText) {
-			completions = append(completions, user)
+		if user.DisplayName == textWithoutPrefix || user.UserID == existingText {
+			// Exact match, return that.
+			return []completion{{user.DisplayName, user.UserID}}
+		}
+
+		if strings.HasPrefix(user.DisplayName, textWithoutPrefix) || strings.HasPrefix(user.UserID, existingText) {
+			completions = append(completions, completion{user.DisplayName, user.UserID})
 		}
 	}
 	return
 }
 
+func (view *RoomView) AutocompleteRoom(existingText string) (completions []completion) {
+	// TODO - This was harder than I expected.
+
+	return []completion{}
+}
+
+func (view *RoomView) InputTabComplete(text string, cursorOffset int) {
+	str := runewidth.Truncate(text, cursorOffset, "")
+	word := findWordToTabComplete(str)
+	startIndex := len(str) - len(word)
+
+	var strCompletions []string
+	var strCompletion string
+
+	completions := view.AutocompleteUser(word)
+	completions = append(completions, view.AutocompleteRoom(word)...)
+
+	if len(completions) == 1 {
+		completion := completions[0]
+		strCompletion = fmt.Sprintf("[%s](https://matrix.to/#/%s)", completion.displayName, completion.id)
+		if startIndex == 0 {
+			strCompletion = strCompletion + ": "
+		}
+	} else if len(completions) > 1 {
+		for _, completion := range completions {
+			strCompletions = append(strCompletions, completion.displayName)
+		}
+	}
+
+	if len(strCompletions) > 0 {
+		strCompletion = util.LongestCommonPrefix(strCompletions)
+		sort.Sort(sort.StringSlice(strCompletions))
+	}
+
+	if len(strCompletion) > 0 {
+		text = str[0:startIndex] + strCompletion + text[len(str):]
+	}
+
+	view.input.SetTextAndMoveCursor(text)
+	view.SetCompletions(strCompletions)
+}
+
 func (view *RoomView) MessageView() *MessageView {
 	return view.content
 }
diff --git a/ui/view-main.go b/ui/view-main.go
index c3e94a5..3034102 100644
--- a/ui/view-main.go
+++ b/ui/view-main.go
@@ -23,7 +23,6 @@ import (
 	"time"
 	"unicode"
 
-	"github.com/mattn/go-runewidth"
 	"maunium.net/go/gomatrix"
 	"maunium.net/go/gomuks/config"
 	"maunium.net/go/gomuks/debug"
@@ -101,28 +100,6 @@ func findWordToTabComplete(text string) string {
 	return output
 }
 
-func (view *MainView) InputTabComplete(roomView *RoomView, text string, cursorOffset int) string {
-	str := runewidth.Truncate(text, cursorOffset, "")
-	word := findWordToTabComplete(str)
-
-	userCompletions := roomView.AutocompleteUser(word)
-	if len(userCompletions) == 1 {
-		startIndex := len(str) - len(word)
-		member := userCompletions[0]
-		completion := fmt.Sprintf("[%s](https://matrix.to/#/%s)", member.DisplayName, member.UserID)
-		if startIndex == 0 {
-			completion = completion + ": "
-		}
-		text = str[0:startIndex] + completion + text[len(str):]
-	} else if len(userCompletions) > 1 && len(userCompletions) <= 5 {
-		// roomView.SetStatus(fmt.Sprintf("Completions: %s", strings.Join(userCompletions, ", ")))
-	} else if len(userCompletions) > 5 {
-		roomView.SetStatus("Over 5 completion options.")
-	}
-
-	return text
-}
-
 func (view *MainView) InputSubmit(roomView *RoomView, text string) {
 	if len(text) == 0 {
 		return
@@ -147,7 +124,7 @@ func (view *MainView) sendTempMessage(roomView *RoomView, tempMessage ifc.Messag
 	eventID, err := view.matrix.SendMarkdownMessage(roomView.Room.ID, tempMessage.Type(), text)
 	if err != nil {
 		tempMessage.SetState(ifc.MessageStateFailed)
-		roomView.SetStatus(fmt.Sprintf("Failed to send message: %s", err))
+		roomView.AddServiceMessage(fmt.Sprintf("Failed to send message: %v", err))
 	} else {
 		roomView.MessageView().UpdateMessageID(tempMessage, eventID)
 	}
@@ -314,7 +291,6 @@ func (view *MainView) addRoom(index int, room string) {
 		roomView := NewRoomView(roomStore).
 			SetInputSubmitFunc(view.InputSubmit).
 			SetInputChangedFunc(view.InputChanged).
-			SetTabCompleteFunc(view.InputTabComplete).
 			SetInputCapture(view.KeyEventHandler).
 			SetMouseCapture(view.MouseEventHandler)
 		view.rooms[room] = roomView
diff --git a/ui/widget/advanced-inputfield.go b/ui/widget/advanced-inputfield.go
index cbe9dcc..a084dcf 100644
--- a/ui/widget/advanced-inputfield.go
+++ b/ui/widget/advanced-inputfield.go
@@ -84,7 +84,7 @@ type AdvancedInputField struct {
 	done func(tcell.Key)
 
 	// An optional function which is called when the user presses tab.
-	tabComplete func(text string, cursorOffset int) string
+	tabComplete func(text string, cursorOffset int)
 }
 
 // NewAdvancedInputField returns a new input field.
@@ -107,6 +107,20 @@ func (field *AdvancedInputField) SetText(text string) *AdvancedInputField {
 	return field
 }
 
+// SetTextAndMoveCursor sets the current text of the input field and moves the cursor with the width difference.
+func (field *AdvancedInputField) SetTextAndMoveCursor(text string) *AdvancedInputField {
+	oldWidth := runewidth.StringWidth(field.text)
+	field.text = text
+	newWidth := runewidth.StringWidth(field.text)
+	if oldWidth != newWidth {
+		field.cursorOffset += newWidth - oldWidth
+	}
+	if field.changed != nil {
+		field.changed(field.text)
+	}
+	return field
+}
+
 // GetText returns the current text of the input field.
 func (field *AdvancedInputField) GetText() string {
 	return field.text
@@ -212,7 +226,7 @@ func (field *AdvancedInputField) SetDoneFunc(handler func(key tcell.Key)) *Advan
 	return field
 }
 
-func (field *AdvancedInputField) SetTabCompleteFunc(handler func(text string, cursorOffset int) string) *AdvancedInputField {
+func (field *AdvancedInputField) SetTabCompleteFunc(handler func(text string, cursorOffset int)) *AdvancedInputField {
 	field.tabComplete = handler
 	return field
 }
@@ -443,12 +457,7 @@ func (field *AdvancedInputField) RemovePreviousCharacter() {
 
 func (field *AdvancedInputField) TriggerTabComplete() bool {
 	if field.tabComplete != nil {
-		oldWidth := runewidth.StringWidth(field.text)
-		field.text = field.tabComplete(field.text, field.cursorOffset)
-		newWidth := runewidth.StringWidth(field.text)
-		if oldWidth != newWidth {
-			field.cursorOffset += newWidth - oldWidth
-		}
+		field.tabComplete(field.text, field.cursorOffset)
 		return true
 	}
 	return false