feat: integrate Pi backend and Pi Web

pi-web/lib/message-display.ts

@@ -0,0 +1,47 @@
+import type { AssistantContentBlock, AssistantMessage, ThinkingContent, ToolCallContent } from "./types";
+
+interface DisplayOptions {
+  isStreaming?: boolean;
+}
+
+export function isEmptyThinkingBlock(block: AssistantContentBlock, options: DisplayOptions = {}): block is ThinkingContent {
+  return block.type === "thinking" && !block.deferred && !options.isStreaming && block.thinking.trim() === "";
+}
+
+export function getDisplayableAssistantBlocks(
+  message: AssistantMessage,
+  options: DisplayOptions = {},
+): AssistantContentBlock[] {
+  return (message.content ?? []).filter((block) => !isEmptyThinkingBlock(block, options));
+}
+
+export function getAssistantErrorMessage(
+  message: AssistantMessage,
+  options: DisplayOptions = {},
+): string | null {
+  if (options.isStreaming || message.stopReason !== "error") return null;
+  return message.errorMessage?.trim() || "Unknown provider error";
+}
+
+function isFinalAnswerBlock(block: AssistantContentBlock): boolean {
+  return block.type === "text" || block.type === "image";
+}
+
+export function splitFinalAssistantBlocks(
+  message: AssistantMessage,
+  options: DisplayOptions = {},
+): { answerBlocks: AssistantContentBlock[]; processBlocks: AssistantContentBlock[] } {
+  const blocks = getDisplayableAssistantBlocks(message, options);
+  const lastProcessIndex = blocks.findLastIndex((block) => !isFinalAnswerBlock(block));
+  if (lastProcessIndex === -1) {
+    return { answerBlocks: blocks, processBlocks: [] };
+  }
+  return {
+    answerBlocks: blocks.slice(lastProcessIndex + 1),
+    processBlocks: blocks.slice(0, lastProcessIndex + 1),
+  };
+}
+
+export function countToolCallBlocks(blocks: AssistantContentBlock[]): number {
+  return blocks.filter((block): block is ToolCallContent => block.type === "toolCall").length;
+}