import { NextRequest, NextResponse } from 'next/server';
import { auth } from '@/app/(auth)/auth';
import { db } from '@/lib/db';
import { canvasProject } from '@/lib/db/schema';
import { syncCanvasNodesForProject } from '@/lib/db/queries';
import { and, desc, eq } from 'drizzle-orm';

function resolveWorkspaceType(input: unknown) {
  return input === "agent" || input === "video" ? input : "canvas";
}

function getDefaultWorkspaceTitle(workspaceType: ReturnType<typeof resolveWorkspaceType>) {
  return workspaceType === "video" ? "未命名视频画布" : "未命名画布";
}

function parsePositiveInteger(input: string | null, fallback: number) {
  const value = Number(input);
  if (!Number.isFinite(value) || value <= 0) {
    return fallback;
  }
  return Math.floor(value);
}

// 获取画布列表
export async function GET(request: NextRequest) {
  try {
    const session = await auth();
    if (!session?.user?.id) {
      return NextResponse.json({ success: false, error: '未登录' }, { status: 401 });
    }

    const workspaceType = resolveWorkspaceType(
      request.nextUrl.searchParams.get("workspaceType")
    );
    const limit = Math.min(
      Math.max(
        parsePositiveInteger(request.nextUrl.searchParams.get("limit"), 24),
        1
      ),
      50
    );
    const page = Math.max(
      parsePositiveInteger(request.nextUrl.searchParams.get("page"), 1),
      1
    );
    const offset = (page - 1) * limit;

    const projects = await db
      .select({
        id: canvasProject.id,
        userId: canvasProject.userId,
        title: canvasProject.title,
        description: canvasProject.description,
        thumbnail: canvasProject.thumbnail,
        workspaceType: canvasProject.workspaceType,
        createdAt: canvasProject.createdAt,
        updatedAt: canvasProject.updatedAt,
      })
      .from(canvasProject)
      .where(
        and(
          eq(canvasProject.userId, session.user.id),
          eq(canvasProject.workspaceType, workspaceType)
        )
      )
      .orderBy(desc(canvasProject.updatedAt))
      .limit(limit + 1)
      .offset(offset);

    const hasMore = projects.length > limit;

    return NextResponse.json({
      success: true,
      data: hasMore ? projects.slice(0, limit) : projects,
      pagination: {
        page,
        limit,
        hasMore,
      },
    });
  } catch (error) {
    console.error('获取画布列表失败:', error);
    return NextResponse.json({ success: false, error: '获取画布列表失败' }, { status: 500 });
  }
}

// 创建画布
export async function POST(request: NextRequest) {
  try {
    const session = await auth();
    if (!session?.user?.id) {
      return NextResponse.json({ success: false, error: '未登录' }, { status: 401 });
    }

    const body = await request.json();
    const { title, description, canvasData } = body;
    const workspaceType = resolveWorkspaceType(body?.workspaceType);

    const [insertedProject] = await db
      .insert(canvasProject)
      .values({
        userId: session.user.id,
        title: title || getDefaultWorkspaceTitle(workspaceType),
        description,
        workspaceType,
        canvasData: canvasData || {
          nodes: [],
          edges: [],
          viewport: { x: 0, y: 0, zoom: 1 },
        },
      })
      .returning();

    let newProject = insertedProject;
    if (canvasData) {
      const syncedCanvasData = await syncCanvasNodesForProject({
        projectId: insertedProject.id,
        userId: session.user.id,
        canvasData,
      });
      const [updatedProject] = await db
        .update(canvasProject)
        .set({
          canvasData: syncedCanvasData,
          updatedAt: new Date(),
        })
        .where(eq(canvasProject.id, insertedProject.id))
        .returning();
      if (updatedProject) {
        newProject = updatedProject;
      }
    }

    return NextResponse.json({ success: true, data: newProject });
  } catch (error) {
    console.error('创建画布失败:', error);
    return NextResponse.json({ success: false, error: '创建画布失败' }, { status: 500 });
  }
}