import { requireAuth } from '~/server/utils/auth'
import { prisma } from '~/server/utils/prisma'

export default defineEventHandler(async (event) => {
  const user = requireAuth(event)
  const id = getRouterParam(event, 'id')
  if (!id) throw createError({ statusCode: 400, message: 'Canvas ID is required' })

  const body = await readBody(event)

  const existing = await prisma.canvas.findUnique({ where: { id } })
  if (!existing) throw createError({ statusCode: 404, message: 'Canvas not found' })
  
  // Allow if owner, or if admin, or if canvas is public (for collaborative editing)
  if (existing.ownerId !== user.id && user.role !== 'admin' && !existing.isPublic) {
    console.log('[DEBUG 403]', { ownerId: existing.ownerId, userId: user.id, userRole: user.role, isPublic: existing.isPublic })
    throw createError({ statusCode: 403, message: 'Access denied' })
  }

  const { name, nodes, edges, isPublic, groupId } = body
  const canvas = await prisma.canvas.update({
    where: { id },
    data: {
      ...(name !== undefined && { name }),
      ...(nodes !== undefined && { nodes }),
      ...(edges !== undefined && { edges }),
      ...(isPublic !== undefined && { isPublic }),
      ...(groupId !== undefined && { groupId: groupId || null })
    }
  })

  return { canvas }
})