package nl.astraeus.nl.astraeus.persistence

import java.io.File
import java.io.ObjectInputStream

class TransactionLog(
  val directory: File,
) {
  val fileManager = FileManager(directory)

  fun showTransactions() {
    fileManager.findLastSnapshot().let { (after, snapshot) ->
      println("Last snapshot: $snapshot")

      println("Snapshot:")
      snapshot?.inputStream()?.use { input ->
        ObjectInputStream(input).use { ois ->
          val versionNumber = ois.readInt()
          check(versionNumber == 1) { "Unsupported version number: $versionNumber" }
          val transactionNumber = ois.readLong()
          println("[$versionNumber]  $transactionNumber")
          val data = ois.readObject() as MutableMap<Class<*>, TypeData>
          println("Data:")
          println("\tClasses:")
          for ((cls, entries) in  data.entries) {
            println("\t\t- $cls: ${entries.data.keys.size}")
          }
        }
      }

      val transactions = fileManager.findTransactionsAfter(after ?: 0L)

      println("Transactions:")
      transactions?.forEach { transaction ->
        transaction.inputStream().use { input ->
          ObjectInputStream(input).use { ois ->
            val versionNumber = ois.readInt()
            check(versionNumber == 1) { "Unsupported version number: $versionNumber" }
            val transactionNumber = ois.readLong()
            val actions = ois.readObject() as Set<Action>
            println("\t[$transactionNumber]")
            for (action in actions) {
              println("\t\t- $action")
            }
          }
        }
      }
    }

  }

}