syntax = "proto3";

// We can't change this to swapserverrpc, it would be a breaking change because
// the package name is also contained in the HTTP URIs and old clients would
// call the wrong endpoints. Luckily with the go_package option we can have
// different golang and RPC package names to fix protobuf namespace conflicts.
package looprpc;

option go_package = "github.com/lightninglabs/loop/swapserverrpc";

service InstantSwapServer {
    rpc RequestInstantLoopOut (InstantLoopOutRequest)
        returns (InstantLoopOutResponse);
    rpc PollPaymentAccepted (PollPaymentAcceptedRequest)
        returns (PollPaymentAcceptedResponse);
    rpc InitHtlcSig (InitHtlcSigRequest) returns (InitHtlcSigResponse);
    rpc PushHtlcSig (PushHtlcSigRequest) returns (PushHtlcSigResponse);
    rpc PushPreimage (PushPreimageRequest) returns (PushPreimageResponse);
}

message InstantLoopOutRequest {
    uint64 amt = 1;

    // Htlc related fields:
    // The key for the htlc preimage spending path.
    bytes receiver_key = 2;

    // T hash of the preimage that will be used to settle the htlc.
    bytes swap_hash = 3;
    // The requested absolute block height of the on-chain htlc. This is
    // subjected to min and max constraints as reported in the LoopOutTerms
    // response.
    int32 expiry = 4;

    // The fee rate in sat/kw that should be used for the htlc.
    uint64 htlc_fee_rate = 5;

    // The reservations used as the inputs.
    repeated bytes reservation_ids = 6;

    InstantOutProtocolVersion protocol_version = 7;
}

message InstantLoopOutResponse {
    string swap_invoice = 1;

    // the key for the htlc expiry path.
    bytes sender_key = 2;
};

message PollPaymentAcceptedRequest {
    bytes swap_hash = 1;
}

message PollPaymentAcceptedResponse {
    bool accepted = 1;
}

message InitHtlcSigRequest {
    bytes swap_hash = 1;
    repeated bytes htlc_client_nonces = 2;
}

message InitHtlcSigResponse {
    repeated bytes htlc_server_nonces = 2;
}

message PushHtlcSigRequest {
    bytes swap_hash = 1;
    repeated bytes client_sigs = 2;
}

message PushHtlcSigResponse {
    repeated bytes server_sigs = 1;
}

message PushPreimageRequest {
    bytes preimage = 1;
    repeated bytes client_nonces = 2;
    string client_sweep_addr = 3;
    uint64 musig_tx_fee_rate = 4;
}

message PushPreimageResponse {
    repeated bytes musig2_sweep_sigs = 1;
    repeated bytes server_nonces = 2;
}

enum InstantOutProtocolVersion {
    INSTANTOUT_NONE = 0;
    INSTANTOUT_FULL_RESERVATION = 1;
};