import { requireAuth } from '~/server/utils/auth'
import { groups, userGroups } from '~/server/utils/db'

export default defineEventHandler(async (event) => {
  const user = requireAuth(event)
  const groupId = getRouterParam(event, 'id')!

  const group = groups.get(groupId)
  if (!group) throw createError({ statusCode: 404, message: 'Group not found' })
  if (group.ownerId === user.id) throw createError({ statusCode: 400, message: 'Owner cannot leave group. Delete it instead.' })

  const key = `${user.id}-${groupId}`
  if (!userGroups.has(key)) throw createError({ statusCode: 400, message: 'Not a member' })

  userGroups.delete(key)
  return { success: true, message: `Left group "${group.name}"` }
})