import { getCollection } from '../../utils/db.js'

export default defineEventHandler(async (event) => {
  try {
    const data = await readBody(event)
    
    // Migrate transactions
    if (data.transactions && data.transactions.length > 0) {
      const transactionsCollection = await getCollection('transactions')
      
      // Clear existing transactions
      await transactionsCollection.deleteMany({})
      
      // Convert and insert transactions
      const mongoTransactions = data.transactions.map(transaction => ({
        ...transaction,
        _id: transaction.id,
        id: undefined,
        date: new Date(transaction.date),
        endDate: transaction.endDate ? new Date(transaction.endDate) : null,
        createdAt: new Date(),
        updatedAt: new Date()
      }))
      
      await transactionsCollection.insertMany(mongoTransactions)
    }
    
    // Migrate balance
    if (data.balance !== undefined) {
      const balancesCollection = await getCollection('balances')
      
      const balanceData = {
        type: 'current',
        currentBalance: data.balance,
        accountBalances: data.accountBalances || {
          manual: {
            rbc_cad: 0,
            td_cad: 0,
            millennium_eur: 0
          },
          wise: {
            jennie: [],
            henry: []
          }
        },
        updatedAt: new Date()
      }
      
      await balancesCollection.replaceOne(
        { type: 'current' },
        balanceData,
        { upsert: true }
      )
    }
    
    return {
      success: true,
      message: 'Data migrated successfully',
      transactionsCount: data.transactions?.length || 0,
      balance: data.balance || 0
    }
  } catch (error) {
    console.error('Error migrating localStorage data:', error)
    throw createError({
      statusCode: 500,
      statusMessage: 'Failed to migrate data'
    })
  }
})