refactor: split dense lines in binary lookup and transcript replay

src/agent/claude-code/transcript.ts

@@ -1,7 +1,9 @@
 import type { ImageContent, Message, TextContent, Tool } from "@earendil-works/pi-ai";
 import { getCurrentSystemPrompt, getCurrentTools } from "@earendil-works/pi-ai/utils/transcript";
 
-export type ClaudeContentBlock = { type: "text"; text: string } | { type: "image"; source: { type: "base64"; media_type: string; data: string } };
+export type ClaudeContentBlock =
+	| { type: "text"; text: string }
+	| { type: "image"; source: { type: "base64"; media_type: string; data: string } };
 
 export type ClaudeInput = {
 	systemPrompt: string;
@@ -17,8 +19,10 @@ function toImageBlock(image: ImageContent): ClaudeContentBlock {
 
 function getLabelledParts(label: string, content: string | (TextContent | ImageContent)[]): ReplayPart[] {
 	if (typeof content === "string") return [`${label}\n${content}`];
+
 	const text = content.flatMap((block) => (block.type === "text" ? [block.text] : [])).join("\n");
 	const images = content.filter((block) => block.type === "image");
+
 	return [text ? `${label}\n${text}` : label, ...images];
 }
 
@@ -26,26 +30,33 @@ function getReplayParts(message: Message): ReplayPart[] {
 	switch (message.role) {
 		case "system":
 			return [];
+
 		case "user":
 			return getLabelledParts("[user]", message.content);
+
 		case "assistant":
 			return message.content.flatMap((block) => {
 				if (block.type === "text") return [`[assistant]\n${block.text}`];
 				if (block.type === "toolCall") return [`[tool call ${block.name}] ${JSON.stringify(block.arguments)}`];
 				return [];
 			});
-		case "toolResult":
-			return getLabelledParts(message.isError ? `[tool result ${message.toolName} error]` : `[tool result ${message.toolName}]`, message.content);
+
+		case "toolResult": {
+			const label = message.isError ? `[tool result ${message.toolName} error]` : `[tool result ${message.toolName}]`;
+			return getLabelledParts(label, message.content);
+		}
 	}
 }
 
 function toContentBlocks(parts: ReplayPart[]): ClaudeContentBlock[] {
 	const blocks: ClaudeContentBlock[] = [];
 	let pendingText: string[] = [];
+
 	const flushText = () => {
 		if (pendingText.length > 0) blocks.push({ type: "text", text: pendingText.join("\n\n") });
 		pendingText = [];
 	};
+
 	for (const part of parts) {
 		if (typeof part === "string") {
 			pendingText.push(part);
@@ -54,20 +65,33 @@ function toContentBlocks(parts: ReplayPart[]): ClaudeContentBlock[] {
 			blocks.push(toImageBlock(part));
 		}
 	}
+
 	flushText();
+
 	return blocks;
 }
 
 function toUnlabelledBlocks(content: string | (TextContent | ImageContent)[]): ClaudeContentBlock[] {
 	if (typeof content === "string") return [{ type: "text", text: content }];
+
 	return content.map((block) => (block.type === "text" ? { type: "text", text: block.text } : toImageBlock(block)));
 }
 
+function toUserContent(conversation: Message[]): ClaudeContentBlock[] {
+	const [first] = conversation;
+	if (conversation.length === 1 && first?.role === "user") return toUnlabelledBlocks(first.content);
+
+	return toContentBlocks(conversation.flatMap(getReplayParts));
+}
+
 export function toClaudeInput(messages: Message[]): ClaudeInput {
 	const conversation = messages.filter((message) => message.role !== "system");
-	const onlyMessage = conversation.length === 1 ? conversation[0] : null;
-	const userContent = onlyMessage?.role === "user" ? toUnlabelledBlocks(onlyMessage.content) : toContentBlocks(conversation.flatMap(getReplayParts));
-	return { systemPrompt: getCurrentSystemPrompt(messages), tools: getCurrentTools(messages), userContent };
+
+	return {
+		systemPrompt: getCurrentSystemPrompt(messages),
+		tools: getCurrentTools(messages),
+		userContent: toUserContent(conversation),
+	};
 }
 
 export function toStreamJsonLine(content: ClaudeContentBlock[]): string {