// SPDX-License-Identifier: MIT
// Copyright (c) 2026 Thibault Ducray
//
// This file is part of MyPwdTool's open-source sync/encryption core — see
// LICENSE-SYNC-CRYPTO.md at the repo root and https://tducray.fr/mypwdtool/open-source/.
// The rest of this application is proprietary and NOT covered by this license.

package fr.tducray.mypwdtool.relay

import kotlinx.serialization.SerialName
import kotlinx.serialization.Serializable

/**
 * Port of the Codable structs in `Sync/RelayAPIClient.swift` and `ServerLimits` in
 * `Sync/SyncModels.swift`. Field names/JSON keys match exactly — these travel over the wire to
 * the same relay server the Swift clients talk to, so any drift here is a real interop bug, not
 * just a style choice.
 */

@Serializable
data class RegistrationChallenge(
    val nonce: String,
    val version: String,
    @SerialName("server_date") val serverDate: String,
    @SerialName("expires_at") val expiresAt: String,
)

@Serializable
data class ServerLimits(
    @SerialName("max_message_bytes") val maxMessageBytes: Int,
    @SerialName("max_messages_per_day") val maxMessagesPerDay: Int,
    @SerialName("default_ttl_seconds") val defaultTtlSeconds: Int,
    @SerialName("max_ttl_seconds") val maxTtlSeconds: Int,
    @SerialName("max_recipients_per_message") val maxRecipientsPerMessage: Int,
) {
    companion object {
        val DEFAULT = ServerLimits(
            maxMessageBytes = 262144,
            maxMessagesPerDay = 20000,
            defaultTtlSeconds = 1296000,
            maxTtlSeconds = 2592000,
            maxRecipientsPerMessage = 50,
        )
    }
}

@Serializable
data class RegisterResponse(
    @SerialName("device_id") val deviceId: String,
    @SerialName("inbox_id") val inboxId: String,
    @SerialName("send_token") val sendToken: String,
    @SerialName("recv_token") val recvToken: String,
    val limits: ServerLimits,
)

data class OutboundRelayMessage(
    val messageId: String,          // UUID, for idempotency
    val streamId: String,
    val senderDeviceId: String,
    val recipientInboxIds: List<String>,
    val ciphertext: String,         // base64url
    val encryptedIdentifier: String? = null, // optional base64url
    val ttlSeconds: Int? = null,
    val cipherVersion: Int = 1,     // always 1
)

@Serializable
data class SendResponse(
    val accepted: Boolean,
    @SerialName("message_id") val messageId: String,
)

@Serializable
data class PollResponse(
    @SerialName("inbox_id") val inboxId: String,
    @SerialName("next_cursor") val nextCursor: String,
    val messages: List<InboundRelayMessage>,
)

@Serializable
data class InboundRelayMessage(
    @SerialName("message_id") val messageId: String,
    @SerialName("stream_id") val streamId: String,
    @SerialName("sender_device_id") val senderDeviceId: String,
    @SerialName("recipient_inbox_ids") val recipientInboxIds: List<String>,
    @SerialName("created_at") val createdAt: String,
    @SerialName("cipher_version") val cipherVersion: Int,
    @SerialName("encrypted_identifier") val encryptedIdentifier: String? = null,
    val ciphertext: String,
)

/** Server error envelope, used to discriminate token_expired/challenge_failed from a plain 401. */
@Serializable
data class RelayApiErrorEnvelope(val error: RelayApiErrorBody)

@Serializable
data class RelayApiErrorBody(val code: String)