using System.Text.Json;
using System.Text.Json.Serialization;

namespace Fleet.Rpc;

/// <summary>框架保留的方法名。<c>fleet.*</c> 只属于框架，产品使用自己的前缀。</summary>
public static class FleetMethods
{
    public const string Challenge = "fleet.challenge";
    public const string Auth = "fleet.auth";
    public const string Hello = "fleet.hello";
    public const string Heartbeat = "fleet.heartbeat";
    public const string Stopping = "fleet.stopping";
    public const string StateSync = "fleet.state.sync";
    public const string OutboxAck = "fleet.outbox.ack";
    public const string Revoked = "fleet.revoked";
}

/// <summary>
/// 框架自己的方法声明，两个平面各一份。认证和握手阶段由连接代码直接处理的（<c>Inline</c>）不经过路由器。
/// 同一个方法名在两个平面里可以有不同的发起方：<c>fleet.state.sync</c> 在节点面是服务端发给节点，在对等面是 Agent 发给 Probe。
/// </summary>
public static class FleetMethodTable
{
    public static readonly MethodTable Table = new(
    [
        // 节点面
        MethodSpec.Notification(FleetMethods.Challenge, RpcSide.Server).AsInline(),
        MethodSpec.Request(FleetMethods.Auth, RpcSide.Node).AsInline(),
        MethodSpec.Request(FleetMethods.Hello, RpcSide.Node).AsInline(),
        MethodSpec.Notification(FleetMethods.Heartbeat, RpcSide.Node).AsInline(),
        MethodSpec.Notification(FleetMethods.Stopping, RpcSide.Node).AsInline(),
        MethodSpec.Request(FleetMethods.StateSync, RpcSide.Server),
        MethodSpec.Notification(FleetMethods.OutboxAck, RpcSide.Server),
        MethodSpec.Notification(FleetMethods.Revoked, RpcSide.Server),

        // 对等面
        MethodSpec.Notification(PeerMethods.Challenge, RpcSide.Listener).AsInline(),
        MethodSpec.Request(PeerMethods.Auth, RpcSide.Dialer).AsInline(),
        MethodSpec.Request(FleetMethods.StateSync, RpcSide.Listener),
        MethodSpec.Notification(FleetMethods.OutboxAck, RpcSide.Listener),
    ]);
}

public sealed class ChallengeParams
{
    [JsonPropertyName("nonce")]
    public string Nonce { get; set; } = "";

    [JsonPropertyName("expires_at_ms")]
    public long ExpiresAtMs { get; set; }

    /// <summary>服务器这次连接的临时 ECDH 公钥（SPKI，base64）；服务器有身份密钥时才有。</summary>
    [JsonPropertyName("server_eph")]
    public string? ServerEphemeral { get; set; }

    /// <summary>服务器密钥对「随机数加临时公钥」的签名（base64）：节点据此确认对面是操作员授权的服务器。</summary>
    [JsonPropertyName("server_sig")]
    public string? ServerSignature { get; set; }
}

public sealed class AuthParams
{
    [JsonPropertyName("node_id")]
    public string NodeId { get; set; } = "";

    /// <summary>对 <c>fleet|v1|auth|{node_id}|{nonce}</c> 的签名（base64）。</summary>
    [JsonPropertyName("signature")]
    public string Signature { get; set; } = "";

    /// <summary>节点的临时 ECDH 公钥（SPKI，base64）：有它就是安全链路，签名覆盖双方的临时公钥，认证结果起所有帧都是加密的。</summary>
    [JsonPropertyName("node_eph")]
    public string? NodeEphemeral { get; set; }
}

public sealed class AuthResult
{
    /// <summary>pending | active</summary>
    [JsonPropertyName("status")]
    public string Status { get; set; } = "";
}

public sealed class HelloParams
{
    [JsonPropertyName("node_version")]
    public string NodeVersion { get; set; } = "";

    [JsonPropertyName("capabilities")]
    public List<string> Capabilities { get; set; } = [];

    [JsonPropertyName("now_utc_ms")]
    public long NowUtcMs { get; set; }

    /// <summary>产品自定义的元数据（例如 MoShiro 的 tls_spki、probe_ports、local_limits 摘要）。</summary>
    [JsonPropertyName("meta")]
    public JsonElement? Meta { get; set; }
}

public sealed class HelloResult
{
    [JsonPropertyName("server_time_ms")]
    public long ServerTimeMs { get; set; }

    /// <summary>节点时钟 − 服务端时钟（毫秒，未扣除网络往返）。</summary>
    [JsonPropertyName("clock_offset_ms")]
    public long ClockOffsetMs { get; set; }
}

public sealed class HeartbeatParams
{
    [JsonPropertyName("extra")]
    public JsonElement? Extra { get; set; }
}

public sealed class StateSyncParams
{
    [JsonPropertyName("type")]
    public string Type { get; set; } = "";

    [JsonPropertyName("version")]
    public long Version { get; set; }

    [JsonPropertyName("doc")]
    public JsonElement Doc { get; set; }
}

public sealed class StateSyncResult
{
    [JsonPropertyName("applied_version")]
    public long AppliedVersion { get; set; }

    [JsonPropertyName("rejected")]
    public List<RejectedItem> Rejected { get; set; } = [];
}

public sealed class RejectedItem
{
    [JsonPropertyName("id")]
    public string Id { get; set; } = "";

    /// <summary>unsupported | budget_exceeded | policy_denied | …</summary>
    [JsonPropertyName("reason")]
    public string Reason { get; set; } = "";
}

public sealed class OutboxAckParams
{
    [JsonPropertyName("ids")]
    public List<string> Ids { get; set; } = [];

    [JsonPropertyName("duplicates")]
    public List<string> Duplicates { get; set; } = [];
}

public sealed class RevokedParams
{
    [JsonPropertyName("reason")]
    public string Reason { get; set; } = "";
}

public sealed class StoppingParams
{
    [JsonPropertyName("reason")]
    public string Reason { get; set; } = "stopping";
}

[JsonSourceGenerationOptions(DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull)]
[JsonSerializable(typeof(RpcMessage))]
[JsonSerializable(typeof(ChallengeParams))]
[JsonSerializable(typeof(AuthParams))]
[JsonSerializable(typeof(AuthResult))]
[JsonSerializable(typeof(HelloParams))]
[JsonSerializable(typeof(HelloResult))]
[JsonSerializable(typeof(HeartbeatParams))]
[JsonSerializable(typeof(StoppingParams))]
[JsonSerializable(typeof(StateSyncParams))]
[JsonSerializable(typeof(StateSyncResult))]
[JsonSerializable(typeof(OutboxAckParams))]
[JsonSerializable(typeof(RevokedParams))]
public sealed partial class FleetRpcContext : JsonSerializerContext;