assistant.go

  1package chat
  2
  3import (
  4	"fmt"
  5	"strings"
  6
  7	tea "charm.land/bubbletea/v2"
  8	"charm.land/lipgloss/v2"
  9	"github.com/charmbracelet/crush/internal/message"
 10	"github.com/charmbracelet/crush/internal/ui/anim"
 11	"github.com/charmbracelet/crush/internal/ui/common"
 12	"github.com/charmbracelet/crush/internal/ui/styles"
 13	"github.com/charmbracelet/x/ansi"
 14)
 15
 16// assistantMessageTruncateFormat is the text shown when an assistant message is
 17// truncated.
 18const assistantMessageTruncateFormat = "… (%d lines hidden) [click or space to expand]"
 19
 20// maxCollapsedThinkingHeight defines the maximum height of the thinking
 21const maxCollapsedThinkingHeight = 10
 22
 23// AssistantMessageItem represents an assistant message in the chat UI.
 24//
 25// This item includes thinking, and the content but does not include the tool calls.
 26type AssistantMessageItem struct {
 27	*highlightableMessageItem
 28	*cachedMessageItem
 29	*focusableMessageItem
 30
 31	message           *message.Message
 32	sty               *styles.Styles
 33	anim              *anim.Anim
 34	thinkingExpanded  bool
 35	thinkingBoxHeight int // Tracks the rendered thinking box height for click detection.
 36}
 37
 38// NewAssistantMessageItem creates a new AssistantMessageItem.
 39func NewAssistantMessageItem(sty *styles.Styles, message *message.Message) MessageItem {
 40	a := &AssistantMessageItem{
 41		highlightableMessageItem: defaultHighlighter(sty),
 42		cachedMessageItem:        &cachedMessageItem{},
 43		focusableMessageItem:     &focusableMessageItem{},
 44		message:                  message,
 45		sty:                      sty,
 46	}
 47
 48	a.anim = anim.New(anim.Settings{
 49		ID:          a.ID(),
 50		Size:        15,
 51		GradColorA:  sty.Primary,
 52		GradColorB:  sty.Secondary,
 53		LabelColor:  sty.FgBase,
 54		CycleColors: true,
 55	})
 56	return a
 57}
 58
 59// StartAnimation starts the assistant message animation if it should be spinning.
 60func (a *AssistantMessageItem) StartAnimation() tea.Cmd {
 61	if !a.isSpinning() {
 62		return nil
 63	}
 64	return a.anim.Start()
 65}
 66
 67// Animate progresses the assistant message animation if it should be spinning.
 68func (a *AssistantMessageItem) Animate(msg anim.StepMsg) tea.Cmd {
 69	if !a.isSpinning() {
 70		return nil
 71	}
 72	return a.anim.Animate(msg)
 73}
 74
 75// ID implements MessageItem.
 76func (a *AssistantMessageItem) ID() string {
 77	return a.message.ID
 78}
 79
 80// RawRender implements [MessageItem].
 81func (a *AssistantMessageItem) RawRender(width int) string {
 82	var spinner string
 83	if a.isSpinning() {
 84		spinner = a.renderSpinning()
 85	}
 86
 87	content, height, ok := a.getCachedRender(width)
 88	if !ok {
 89		content = a.renderMessageContent(width)
 90		height = lipgloss.Height(content)
 91		// cache the rendered content
 92		a.setCachedRender(content, width, height)
 93	}
 94
 95	highlightedContent := a.renderHighlighted(content, width, height)
 96	if spinner != "" {
 97		if highlightedContent != "" {
 98			highlightedContent += "\n\n"
 99		}
100		return highlightedContent + spinner
101	}
102
103	return highlightedContent
104}
105
106// Render implements MessageItem.
107func (a *AssistantMessageItem) Render(width int) string {
108	style := a.sty.Chat.Message.AssistantBlurred
109	if a.focused {
110		style = a.sty.Chat.Message.AssistantFocused
111	}
112	return style.Render(a.RawRender(width))
113}
114
115// renderMessageContent renders the message content including thinking, main content, and finish reason.
116func (a *AssistantMessageItem) renderMessageContent(width int) string {
117	var messageParts []string
118	thinking := strings.TrimSpace(a.message.ReasoningContent().Thinking)
119	content := strings.TrimSpace(a.message.Content().Text)
120	// if the massage has reasoning content add that first
121	if thinking != "" {
122		messageParts = append(messageParts, a.renderThinking(a.message.ReasoningContent().Thinking, width))
123	}
124
125	// then add the main content
126	if content != "" {
127		// add a spacer between thinking and content
128		if thinking != "" {
129			messageParts = append(messageParts, "")
130		}
131		messageParts = append(messageParts, a.renderMarkdown(content, width))
132	}
133
134	// finally add any finish reason info
135	if a.message.IsFinished() {
136		switch a.message.FinishReason() {
137		case message.FinishReasonCanceled:
138			messageParts = append(messageParts, a.sty.Base.Italic(true).Render("Canceled"))
139		case message.FinishReasonError:
140			messageParts = append(messageParts, a.renderError(width))
141		}
142	}
143
144	return strings.Join(messageParts, "\n")
145}
146
147// renderThinking renders the thinking/reasoning content with footer.
148func (a *AssistantMessageItem) renderThinking(thinking string, width int) string {
149	renderer := common.PlainMarkdownRenderer(a.sty, width)
150	rendered, err := renderer.Render(thinking)
151	if err != nil {
152		rendered = thinking
153	}
154	rendered = strings.TrimSpace(rendered)
155
156	lines := strings.Split(rendered, "\n")
157	totalLines := len(lines)
158
159	isTruncated := totalLines > maxCollapsedThinkingHeight
160	if !a.thinkingExpanded && isTruncated {
161		lines = lines[totalLines-maxCollapsedThinkingHeight:]
162		hint := a.sty.Chat.Message.ThinkingTruncationHint.Render(
163			fmt.Sprintf(assistantMessageTruncateFormat, totalLines-maxCollapsedThinkingHeight),
164		)
165		lines = append([]string{hint, ""}, lines...)
166	}
167
168	thinkingStyle := a.sty.Chat.Message.ThinkingBox.Width(width)
169	result := thinkingStyle.Render(strings.Join(lines, "\n"))
170	a.thinkingBoxHeight = lipgloss.Height(result)
171
172	var footer string
173	// if thinking is done add the thought for footer
174	if !a.message.IsThinking() || len(a.message.ToolCalls()) > 0 {
175		duration := a.message.ThinkingDuration()
176		if duration.String() != "0s" {
177			footer = a.sty.Chat.Message.ThinkingFooterTitle.Render("Thought for ") +
178				a.sty.Chat.Message.ThinkingFooterDuration.Render(duration.String())
179		}
180	}
181
182	if footer != "" {
183		result += "\n\n" + footer
184	}
185
186	return result
187}
188
189// renderMarkdown renders content as markdown.
190func (a *AssistantMessageItem) renderMarkdown(content string, width int) string {
191	renderer := common.MarkdownRenderer(a.sty, width)
192	result, err := renderer.Render(content)
193	if err != nil {
194		return content
195	}
196	return strings.TrimSuffix(result, "\n")
197}
198
199func (a *AssistantMessageItem) renderSpinning() string {
200	if a.message.IsThinking() {
201		a.anim.SetLabel("Thinking")
202	} else if a.message.IsSummaryMessage {
203		a.anim.SetLabel("Summarizing")
204	}
205	return a.anim.Render()
206}
207
208// renderError renders an error message.
209func (a *AssistantMessageItem) renderError(width int) string {
210	finishPart := a.message.FinishPart()
211	errTag := a.sty.Chat.Message.ErrorTag.Render("ERROR")
212	truncated := ansi.Truncate(finishPart.Message, width-2-lipgloss.Width(errTag), "...")
213	title := fmt.Sprintf("%s %s", errTag, a.sty.Chat.Message.ErrorTitle.Render(truncated))
214	details := a.sty.Chat.Message.ErrorDetails.Width(width - 2).Render(finishPart.Details)
215	return fmt.Sprintf("%s\n\n%s", title, details)
216}
217
218// isSpinning returns true if the assistant message is still generating.
219func (a *AssistantMessageItem) isSpinning() bool {
220	isThinking := a.message.IsThinking()
221	isFinished := a.message.IsFinished()
222	hasContent := strings.TrimSpace(a.message.Content().Text) != ""
223	hasToolCalls := len(a.message.ToolCalls()) > 0
224	return (isThinking || !isFinished) && !hasContent && !hasToolCalls
225}
226
227// SetMessage is used to update the underlying message.
228func (a *AssistantMessageItem) SetMessage(message *message.Message) tea.Cmd {
229	wasSpinning := a.isSpinning()
230	a.message = message
231	a.clearCache()
232	if !wasSpinning && a.isSpinning() {
233		return a.StartAnimation()
234	}
235	return nil
236}
237
238// ToggleExpanded toggles the expanded state of the thinking box.
239func (a *AssistantMessageItem) ToggleExpanded() {
240	a.thinkingExpanded = !a.thinkingExpanded
241	a.clearCache()
242}
243
244// HandleMouseClick implements MouseClickable.
245func (a *AssistantMessageItem) HandleMouseClick(btn ansi.MouseButton, x, y int) bool {
246	if btn != ansi.MouseLeft {
247		return false
248	}
249	// check if the click is within the thinking box
250	if a.thinkingBoxHeight > 0 && y < a.thinkingBoxHeight {
251		a.ToggleExpanded()
252		return true
253	}
254	return false
255}
256
257// HandleKeyEvent implements KeyEventHandler.
258func (a *AssistantMessageItem) HandleKeyEvent(key tea.KeyMsg) (bool, tea.Cmd) {
259	if k := key.String(); k == "c" || k == "y" {
260		text := a.message.Content().Text
261		return true, common.CopyToClipboard(text, "Message copied to clipboard")
262	}
263	return false, nil
264}