SvelteKit-based WebUI (#14839)

tools/server/webui/src/lib/utils/thinking.ts

@@ -0,0 +1,90 @@
+/**
+ * Parses thinking content from a message that may contain <think> tags
+ * Returns an object with thinking content and cleaned message content
+ * Handles both complete <think>...</think> blocks and incomplete <think> blocks (streaming)
+ * @param content - The message content to parse
+ * @returns An object containing the extracted thinking content and the cleaned message content
+ */
+export function parseThinkingContent(content: string): {
+	thinking: string | null;
+	cleanContent: string;
+} {
+	const incompleteMatch = content.includes('<think>') && !content.includes('</think>');
+
+	if (incompleteMatch) {
+		// Remove the entire <think>... part from clean content
+		const cleanContent = content.split('</think>')?.[1]?.trim();
+		// Extract everything after <think> as thinking content
+		const thinkingContent = content.split('<think>')?.[1]?.trim();
+
+		return {
+			cleanContent,
+			thinking: thinkingContent
+		};
+	}
+
+	const completeMatch = content.includes('</think>');
+
+	if (completeMatch) {
+		return {
+			thinking: content.split('</think>')?.[0]?.trim(),
+			cleanContent: content.split('</think>')?.[1]?.trim()
+		};
+	}
+
+	return {
+		thinking: null,
+		cleanContent: content
+	};
+}
+
+/**
+ * Checks if content contains an opening <think> tag (for streaming)
+ * @param content - The message content to check
+ * @returns True if the content contains an opening <think> tag
+ */
+export function hasThinkingStart(content: string): boolean {
+	return content.includes('<think>') || content.includes('<|channel|>analysis');
+}
+
+/**
+ * Checks if content contains a closing </think> tag (for streaming)
+ * @param content - The message content to check
+ * @returns True if the content contains a closing </think> tag
+ */
+export function hasThinkingEnd(content: string): boolean {
+	return content.includes('</think>');
+}
+
+/**
+ * Extracts partial thinking content during streaming
+ * Used when we have <think> but not yet </think>
+ * @param content - The message content to extract partial thinking from
+ * @returns An object containing the extracted partial thinking content and the remaining content
+ */
+export function extractPartialThinking(content: string): {
+	thinking: string | null;
+	remainingContent: string;
+} {
+	const startIndex = content.indexOf('<think>');
+	if (startIndex === -1) {
+		return { thinking: null, remainingContent: content };
+	}
+
+	const endIndex = content.indexOf('</think>');
+	if (endIndex === -1) {
+		// Still streaming thinking content
+		const thinkingStart = startIndex + '<think>'.length;
+		return {
+			thinking: content.substring(thinkingStart),
+			remainingContent: content.substring(0, startIndex)
+		};
+	}
+
+	// Complete thinking block found
+	const parsed = parseThinkingContent(content);
+	return {
+		thinking: parsed.thinking,
+		remainingContent: parsed.cleanContent
+	};
+}