import { NextResponse } from "next/server";
import { z } from "zod";
import { auth } from "@/app/(auth)/auth";
import { getChatById, getMessagesByChatId } from "@/lib/db/queries";
import {
  readOwnedVideoCanvas,
  saveVideoAgentCanvas,
} from "@/lib/ai/canvas-agent-runtime/video-store";
import { AgentRunError } from "@/lib/ai/canvas-agent-runtime/store";
import { publicAgentError } from "@/lib/ai/canvas-agent-runtime/protocol";

export const dynamic = "force-dynamic";
export async function GET(request: Request) {
  const session = await auth();
  if (!session?.user?.id) return NextResponse.json({ error: "未登录" }, { status: 401 });
  try {
    const projectId = z.string().uuid().parse(new URL(request.url).searchParams.get("projectId"));
    await readOwnedVideoCanvas(session.user.id, projectId);
    // One stable conversation per video workspace survives browser reloads.
    const chat = await getChatById({ id: projectId });
    if (chat && chat.userId !== session.user.id) throw new AgentRunError("对话不存在", 404);
    const messages = chat ? (await getMessagesByChatId({ id: projectId })).slice(-40) : [];
    return NextResponse.json(
      { messages: messages.map(({ id, role, parts }) => ({ id, role, parts })) },
      { headers: { "Cache-Control": "private, no-store" } },
    );
  } catch (error) {
    return NextResponse.json(
      { error: publicAgentError(error) },
      {
        status:
          error instanceof AgentRunError ? error.status : error instanceof z.ZodError ? 400 : 503,
      },
    );
  }
}

const saveSchema = z.object({
  projectId: z.string().uuid(),
  baseRevision: z.string().datetime(),
  canvasData: z.object({
    nodes: z.array(z.record(z.unknown())).max(2000),
    edges: z
      .array(
        z.object({
          id: z.string(),
          source: z.string(),
          target: z.string(),
          type: z.string().optional(),
        }),
      )
      .max(4000),
    selectedNodeIds: z.array(z.string()).max(20),
    viewport: z.object({
      x: z.number().finite(),
      y: z.number().finite(),
      zoom: z.number().positive(),
    }),
    tool: z.literal("select"),
  }),
});
export async function POST(request: Request) {
  const session = await auth();
  if (!session?.user?.id) return NextResponse.json({ error: "未登录" }, { status: 401 });
  try {
    const body = saveSchema.parse(await request.json());
    await saveVideoAgentCanvas(session.user.id, body.projectId, body.baseRevision, body.canvasData);
    return NextResponse.json({ success: true });
  } catch (error) {
    return NextResponse.json(
      { error: publicAgentError(error) },
      {
        status:
          error instanceof AgentRunError ? error.status : error instanceof z.ZodError ? 400 : 503,
      },
    );
  }
}