import { getQuery } from 'h3'
import { startOfMonth, endOfMonth } from 'date-fns'
import { prisma } from '../../utils/db'
import { requireUser } from '../../utils/auth'

export default defineEventHandler(async (event) => {
  const user = await requireUser(event)
  const query = getQuery(event)
  const includeInactive = query.includeInactive === 'true'
  const month = typeof query.month === 'string' ? query.month : new Date().toISOString().slice(0, 7)
  const monthStart = startOfMonth(new Date(`${month}-01T00:00:00`))
  const monthEnd = endOfMonth(monthStart)

  const assets = await prisma.asset.findMany({
    where: { userId: user.id, ...(includeInactive ? {} : { active: true }) },
    orderBy: [{ sortOrder: 'asc' }, { createdAt: 'asc' }]
  })

  const balances = await Promise.all(assets.map(async (asset) => {
    const where = {
      userId: user.id,
      assetId: asset.id,
      ...(asset.balanceType === 'monthly_reset'
        ? { occurredAt: { gte: monthStart, lte: monthEnd } }
        : {})
    }
    const [income, expense] = await Promise.all([
      prisma.transaction.aggregate({ where: { ...where, type: 'income' }, _sum: { amount: true } }),
      prisma.transaction.aggregate({ where: { ...where, type: 'expense' }, _sum: { amount: true } })
    ])
    const base = asset.balanceType === 'cumulative' ? asset.initialBalance : 0
    return {
      ...asset,
      balance: base + (income._sum.amount || 0) - (expense._sum.amount || 0)
    }
  }))

  return balances
})