fix(tui): allow character-by-character editing of TUI file attachments

packages/tui/internal/components/dialog/complete.go

@@ -34,6 +34,7 @@ type CompletionDialog interface {
 	tea.ViewModel
 	SetWidth(width int)
 	IsEmpty() bool
+	SetInitialText(text string) tea.Cmd
 }
 
 type completionDialogComponent struct {
@@ -64,53 +65,58 @@ func (c *completionDialogComponent) Init() tea.Cmd {
 	return nil
 }
 
-func (c *completionDialogComponent) getAllCompletions(query string) tea.Cmd {
-	return func() tea.Msg {
-		allItems := make([]completions.CompletionSuggestion, 0)
-		providersWithResults := 0
+// buildCompletionList queries providers and builds a ranked list of completions
+func (c *completionDialogComponent) buildCompletionList(query string) []completions.CompletionSuggestion {
+	allItems := make([]completions.CompletionSuggestion, 0)
+	providersWithResults := 0
+
+	// Collect results from all providers
+	for _, provider := range c.providers {
+		items, err := provider.GetChildEntries(query)
+		if err != nil {
+			slog.Error(
+				"Failed to get completion items",
+				"provider",
+				provider.GetId(),
+				"error",
+				err,
+			)
+			continue
+		}
+		if len(items) > 0 {
+			providersWithResults++
+			allItems = append(allItems, items...)
+		}
+	}
 
-		// Collect results from all providers
-		for _, provider := range c.providers {
-			items, err := provider.GetChildEntries(query)
-			if err != nil {
-				slog.Error(
-					"Failed to get completion items",
-					"provider",
-					provider.GetId(),
-					"error",
-					err,
-				)
-				continue
-			}
-			if len(items) > 0 {
-				providersWithResults++
-				allItems = append(allItems, items...)
-			}
+	// If there's a query, use fuzzy ranking to sort results
+	if query != "" && providersWithResults > 1 {
+		t := theme.CurrentTheme()
+		baseStyle := styles.NewStyle().Background(t.BackgroundElement())
+		// Create a slice of display values for fuzzy matching
+		displayValues := make([]string, len(allItems))
+		for i, item := range allItems {
+			displayValues[i] = item.Display(baseStyle)
 		}
 
-		// If there's a query, use fuzzy ranking to sort results
-		if query != "" && providersWithResults > 1 {
-			t := theme.CurrentTheme()
-			baseStyle := styles.NewStyle().Background(t.BackgroundElement())
-			// Create a slice of display values for fuzzy matching
-			displayValues := make([]string, len(allItems))
-			for i, item := range allItems {
-				displayValues[i] = item.Display(baseStyle)
-			}
+		matches := fuzzy.RankFindFold(query, displayValues)
+		sort.Sort(matches)
 
-			matches := fuzzy.RankFindFold(query, displayValues)
-			sort.Sort(matches)
+		// Reorder items based on fuzzy ranking
+		rankedItems := make([]completions.CompletionSuggestion, 0, len(matches))
+		for _, match := range matches {
+			rankedItems = append(rankedItems, allItems[match.OriginalIndex])
+		}
 
-			// Reorder items based on fuzzy ranking
-			rankedItems := make([]completions.CompletionSuggestion, 0, len(matches))
-			for _, match := range matches {
-				rankedItems = append(rankedItems, allItems[match.OriginalIndex])
-			}
+		return rankedItems
+	}
 
-			return rankedItems
-		}
+	return allItems
+}
 
-		return allItems
+func (c *completionDialogComponent) getAllCompletions(query string) tea.Cmd {
+	return func() tea.Msg {
+		return c.buildCompletionList(query)
 	}
 }
 func (c *completionDialogComponent) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
@@ -191,6 +197,21 @@ func (c *completionDialogComponent) IsEmpty() bool {
 	return c.list.IsEmpty()
 }
 
+func (c *completionDialogComponent) SetInitialText(text string) tea.Cmd {
+	c.pseudoSearchTextArea.SetValue(text)
+	query := strings.TrimPrefix(text, c.trigger)
+	c.query = query
+
+	// Use the shared completion logic
+	allItems := c.buildCompletionList(query)
+
+	// Update the list with filtered results immediately
+	c.list.SetItems(allItems)
+
+	// Return focus command like the normal flow does
+	return c.pseudoSearchTextArea.Focus()
+}
+
 func (c *completionDialogComponent) complete(item completions.CompletionSuggestion) tea.Cmd {
 	value := c.pseudoSearchTextArea.Value()
 	return tea.Batch(

packages/tui/internal/components/textarea/textarea.go

@@ -1567,6 +1567,34 @@ func (m Model) Update(msg tea.Msg) (Model, tea.Cmd) {
 				break
 			}
 			if len(m.value[m.row]) > 0 && m.col > 0 {
+				if att, ok := m.value[m.row][m.col-1].(*Attachment); ok {
+					var filePath string
+					if att.Filename != "" {
+						filePath = att.Filename
+					} else {
+						filePath = strings.TrimPrefix(att.Display, "@")
+					}
+
+					fullText := "@" + filePath
+					if len(fullText) > 1 {
+						fullText = fullText[:len(fullText)-1] 
+					}
+
+					m.value[m.row] = slices.Delete(m.value[m.row], m.col-1, m.col)
+
+					textRunes := []rune(fullText)
+					textInterfaces := make([]any, len(textRunes))
+					for i, r := range textRunes {
+						textInterfaces[i] = r
+					}
+					m.value[m.row] = slices.Insert(m.value[m.row], m.col-1, textInterfaces...)
+
+					m.SetCursorColumn(m.col - 1 + len(textRunes))
+
+					return m, func() tea.Msg {
+						return tea.KeyPressMsg{Text: fullText}
+					}
+				}
 				m.value[m.row] = slices.Delete(m.value[m.row], m.col-1, m.col)
 				m.SetCursorColumn(m.col - 1)
 			}

packages/tui/internal/tui/tui.go

@@ -167,20 +167,30 @@ func (a appModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			return a, tea.Sequence(cmds...)
 		}
 
-		// Handle file completions trigger
-		if keyString == "@" &&
+		// Handle file completions trigger - both single @ and text starting with @
+		if (keyString == "@" || strings.HasPrefix(msg.Text, "@")) &&
 			!a.showCompletionDialog {
 			a.showCompletionDialog = true
 
-			updated, cmd := a.editor.Update(msg)
-			a.editor = updated.(chat.EditorComponent)
-			cmds = append(cmds, cmd)
+			if len(msg.Text) == 1 || keyString == "@" {
+				updated, cmd := a.editor.Update(msg)
+				a.editor = updated.(chat.EditorComponent)
+				cmds = append(cmds, cmd)
+			}
 
-			// Set both file and symbols providers for @ completion
 			a.completions = dialog.NewCompletionDialogComponent("@", a.fileProvider, a.symbolsProvider)
-			updated, cmd = a.completions.Update(msg)
-			a.completions = updated.(dialog.CompletionDialog)
-			cmds = append(cmds, cmd)
+
+			// If it's more than just "@", set the initial text and handle the returned command
+			if len(msg.Text) > 1 && strings.HasPrefix(msg.Text, "@") {
+				cmd := a.completions.SetInitialText(msg.Text)
+				cmds = append(cmds, cmd)
+				// Don't call Update - SetInitialText already handled the text and search
+			} else {
+				// Normal single "@" keypress - call Update to process the keypress
+				updated, cmd := a.completions.Update(msg)
+				a.completions = updated.(dialog.CompletionDialog)
+				cmds = append(cmds, cmd)
+			}
 
 			return a, tea.Sequence(cmds...)
 		}