refactor(src): split oversized modules

src/agents/pi-embedded-helpers/turns.ts

@@ -0,0 +1,124 @@
+import type { AgentMessage } from "@mariozechner/pi-agent-core";
+
+/**
+ * Validates and fixes conversation turn sequences for Gemini API.
+ * Gemini requires strict alternating user→assistant→tool→user pattern.
+ * Merges consecutive assistant messages together.
+ */
+export function validateGeminiTurns(messages: AgentMessage[]): AgentMessage[] {
+  if (!Array.isArray(messages) || messages.length === 0) {
+    return messages;
+  }
+
+  const result: AgentMessage[] = [];
+  let lastRole: string | undefined;
+
+  for (const msg of messages) {
+    if (!msg || typeof msg !== "object") {
+      result.push(msg);
+      continue;
+    }
+
+    const msgRole = (msg as { role?: unknown }).role as string | undefined;
+    if (!msgRole) {
+      result.push(msg);
+      continue;
+    }
+
+    if (msgRole === lastRole && lastRole === "assistant") {
+      const lastMsg = result[result.length - 1];
+      const currentMsg = msg as Extract<AgentMessage, { role: "assistant" }>;
+
+      if (lastMsg && typeof lastMsg === "object") {
+        const lastAsst = lastMsg as Extract<
+          AgentMessage,
+          { role: "assistant" }
+        >;
+        const mergedContent = [
+          ...(Array.isArray(lastAsst.content) ? lastAsst.content : []),
+          ...(Array.isArray(currentMsg.content) ? currentMsg.content : []),
+        ];
+
+        const merged: Extract<AgentMessage, { role: "assistant" }> = {
+          ...lastAsst,
+          content: mergedContent,
+          ...(currentMsg.usage && { usage: currentMsg.usage }),
+          ...(currentMsg.stopReason && { stopReason: currentMsg.stopReason }),
+          ...(currentMsg.errorMessage && {
+            errorMessage: currentMsg.errorMessage,
+          }),
+        };
+
+        result[result.length - 1] = merged;
+        continue;
+      }
+    }
+
+    result.push(msg);
+    lastRole = msgRole;
+  }
+
+  return result;
+}
+
+export function mergeConsecutiveUserTurns(
+  previous: Extract<AgentMessage, { role: "user" }>,
+  current: Extract<AgentMessage, { role: "user" }>,
+): Extract<AgentMessage, { role: "user" }> {
+  const mergedContent = [
+    ...(Array.isArray(previous.content) ? previous.content : []),
+    ...(Array.isArray(current.content) ? current.content : []),
+  ];
+
+  return {
+    ...current,
+    content: mergedContent,
+    timestamp: current.timestamp ?? previous.timestamp,
+  };
+}
+
+/**
+ * Validates and fixes conversation turn sequences for Anthropic API.
+ * Anthropic requires strict alternating user→assistant pattern.
+ * Merges consecutive user messages together.
+ */
+export function validateAnthropicTurns(
+  messages: AgentMessage[],
+): AgentMessage[] {
+  if (!Array.isArray(messages) || messages.length === 0) {
+    return messages;
+  }
+
+  const result: AgentMessage[] = [];
+  let lastRole: string | undefined;
+
+  for (const msg of messages) {
+    if (!msg || typeof msg !== "object") {
+      result.push(msg);
+      continue;
+    }
+
+    const msgRole = (msg as { role?: unknown }).role as string | undefined;
+    if (!msgRole) {
+      result.push(msg);
+      continue;
+    }
+
+    if (msgRole === lastRole && lastRole === "user") {
+      const lastMsg = result[result.length - 1];
+      const currentMsg = msg as Extract<AgentMessage, { role: "user" }>;
+
+      if (lastMsg && typeof lastMsg === "object") {
+        const lastUser = lastMsg as Extract<AgentMessage, { role: "user" }>;
+        const merged = mergeConsecutiveUserTurns(lastUser, currentMsg);
+        result[result.length - 1] = merged;
+        continue;
+      }
+    }
+
+    result.push(msg);
+    lastRole = msgRole;
+  }
+
+  return result;
+}