refactor: ChatMessage.chunks[] union — interleaved thinking, tool batching, error/system chunks

2 files changed, 47 insertions, 22 deletions

diff --git a/packages/core/src/db/index.ts b/packages/core/src/db/index.ts
index 81b474e..e63b266 100644
--- a/packages/core/src/db/index.ts
+++ b/packages/core/src/db/index.ts
@@ -99,7 +99,6 @@ export function getDatabase(): Database {
 		seq          INTEGER NOT NULL,
 		role         TEXT NOT NULL,
 		content_json TEXT NOT NULL,
-		thinking     TEXT,
 		created_at   INTEGER NOT NULL
 	)`);
 
diff --git a/packages/core/src/db/messages.ts b/packages/core/src/db/messages.ts
index 80a1f22..34b69e5 100644
--- a/packages/core/src/db/messages.ts
+++ b/packages/core/src/db/messages.ts
@@ -1,21 +1,29 @@
+import type { Chunk, MessageRole } from "../types/index.js";
 import { getDatabase } from "./index.js";
 
+/**
+ * A persisted message row, with `content_json` already parsed into a `Chunk[]`.
+ * Mirrors the new schema (no `thinking` column — that lived under the old
+ * `content + toolCalls + toolResults + thinking` model).
+ */
 export interface MessageRow {
 	id: string;
 	tabId: string;
 	seq: number;
-	role: string;
-	contentJson: string;
-	thinking: string | null;
+	role: MessageRole;
+	chunks: Chunk[];
 	createdAt: number;
 }
 
+/**
+ * Append a new message to the tab. Caller passes the already-serialized
+ * chunk list as `contentJson` (i.e. `JSON.stringify(chunks)`).
+ */
 export function appendMessage(
 	tabId: string,
 	id: string,
-	role: string,
+	role: MessageRole,
 	contentJson: string,
-	thinking?: string,
 ): void {
 	const db = getDatabase();
 	const maxSeq = db
@@ -23,40 +31,58 @@ export function appendMessage(
 		.get({ $tabId: tabId }) as { max_seq: number };
 	const seq = (maxSeq?.max_seq ?? -1) + 1;
 	db.query(
-		`INSERT INTO messages (id, tab_id, seq, role, content_json, thinking, created_at)
-		 VALUES ($id, $tabId, $seq, $role, $contentJson, $thinking, $now)`,
+		`INSERT INTO messages (id, tab_id, seq, role, content_json, created_at)
+		 VALUES ($id, $tabId, $seq, $role, $contentJson, $now)`,
 	).run({
 		$id: id,
 		$tabId: tabId,
 		$seq: seq,
 		$role: role,
 		$contentJson: contentJson,
-		$thinking: thinking ?? null,
 		$now: Date.now(),
 	});
 }
 
-export function updateMessage(id: string, contentJson: string, thinking?: string): void {
+/**
+ * Replace the persisted chunks for an existing message. `contentJson` is
+ * the already-serialized chunk list.
+ */
+export function updateMessage(id: string, contentJson: string): void {
 	const db = getDatabase();
-	db.query(
-		"UPDATE messages SET content_json = $contentJson, thinking = $thinking WHERE id = $id",
-	).run({ $id: id, $contentJson: contentJson, $thinking: thinking ?? null });
+	db.query("UPDATE messages SET content_json = $contentJson WHERE id = $id").run({
+		$id: id,
+		$contentJson: contentJson,
+	});
 }
 
+/**
+ * Read all messages for a tab in seq order. `content_json` is parsed into
+ * `Chunk[]` here so callers don't have to. If a row's JSON is malformed,
+ * the message is returned with an empty chunk list rather than throwing.
+ */
 export function getMessagesForTab(tabId: string): MessageRow[] {
 	const db = getDatabase();
 	const rows = db
 		.query("SELECT * FROM messages WHERE tab_id = $tabId ORDER BY seq ASC")
 		.all({ $tabId: tabId }) as Array<Record<string, unknown>>;
-	return rows.map((row) => ({
-		id: row.id as string,
-		tabId: row.tab_id as string,
-		seq: row.seq as number,
-		role: row.role as string,
-		contentJson: row.content_json as string,
-		thinking: row.thinking as string | null,
-		createdAt: row.created_at as number,
-	}));
+	return rows.map((row) => {
+		const rawJson = row.content_json as string;
+		let chunks: Chunk[];
+		try {
+			const parsed = JSON.parse(rawJson);
+			chunks = Array.isArray(parsed) ? (parsed as Chunk[]) : [];
+		} catch {
+			chunks = [];
+		}
+		return {
+			id: row.id as string,
+			tabId: row.tab_id as string,
+			seq: row.seq as number,
+			role: row.role as MessageRole,
+			chunks,
+			createdAt: row.created_at as number,
+		};
+	});
 }
 
 export function clearMessagesForTab(tabId: string): void {