/*
 * Copyright 2024 Dominic Grimm
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.dergrimm.keycloak.providers.events.mqtt

import org.keycloak.events.Event
import org.keycloak.events.admin.AdminEvent
import org.keycloak.models.KeycloakSession
import org.keycloak.events.admin.ResourceType
import io.bullet.borer.{Codec, Encoder}
import io.bullet.borer.derivation.MapBasedCodecs._
import io.bullet.borer.NullOptions.given

object Payload extends FromEvent[Payload]:
  def fromEvent(event: Event, session: KeycloakSession): Payload =
    val error: Option[String] = Option(event.getError())
    val realmId: String = event.getRealmId()

    Payload(
      admin = false,
      time = event.getTime(),
      realm = session.realms().getRealm(realmId).getName(),
      realmId,
      authDetails = PayloadAuthDetails.fromEvent(event, session),
      resourceType = None,
      operationType = event.getType().toString(),
      resourcePath = None,
      representation = None,
      error
    )
  end fromEvent

  def fromEvent(event: AdminEvent, session: KeycloakSession): Payload =
    val resourceType: Option[String] =
      Option(event.getResourceType()).map(_.toString())
    val representation: Option[String] = Option(event.getRepresentation())
    val error: Option[String] = Option(event.getError())
    val realmId: String = event.getRealmId()

    Payload(
      admin = true,
      time = event.getTime(),
      realm = session.realms().getRealm(realmId).getName(),
      realmId,
      authDetails = PayloadAuthDetails.fromEvent(event, session),
      resourceType,
      operationType = event.getOperationType().toString(),
      resourcePath = Some(event.getResourcePath()),
      representation,
      error
    )
  end fromEvent
end Payload

private final case class Payload(
    admin: Boolean,
    time: Long,
    realm: String,
    realmId: String,
    authDetails: PayloadAuthDetails,
    resourceType: Option[String],
    operationType: String,
    resourcePath: Option[String],
    representation: Option[String],
    error: Option[String]
) derives Codec:
  private def result: String = if error.isDefined then "error" else "success"

  def topic: String =
    if admin
    then
      resourceType match
        case Some(rType) =>
          s"admin/${realm}/${result}/${rType.toLowerCase()}/${operationType.toLowerCase()}"
        case None => throw new IllegalStateException
    else
      s"client/${realm}/${result}/${authDetails.clientId}/${operationType.toLowerCase()}"
  end topic
end Payload