// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.

syntax = "proto3";
option go_package = "pb";

package piecestore;

import "gogo.proto";
import "google/protobuf/timestamp.proto";
import "orders.proto";

service Piecestore {
    rpc Upload(stream PieceUploadRequest) returns (PieceUploadResponse) {}
    rpc Download(stream PieceDownloadRequest) returns (stream PieceDownloadResponse) {}
    rpc Delete(PieceDeleteRequest) returns (PieceDeleteResponse) {
      option deprecated = true;
    }
    // DeletePiece deletes a piece from a satellite request
    rpc DeletePiece(PieceDeletePieceRequest) returns (PieceDeletePieceResponse);
    rpc Retain(RetainRequest) returns (RetainResponse);
    rpc RestoreTrash(RestoreTrashRequest) returns (RestoreTrashResponse) {}
}

// Expected order of messages from uplink:
//   OrderLimit ->
//   repeated
//      Order ->
//      Chunk ->
//   PieceHash signed by uplink ->
//      <- PieceHash signed by storage node
//
message PieceUploadRequest {
    // first message to show that we are allowed to upload
    orders.OrderLimit limit = 1;
    // order for uploading
    orders.Order      order = 2;

    // data message
    message Chunk {
        int64 offset = 1;
        bytes data = 2;
    }
    Chunk      chunk = 3;
    // final message
    orders.PieceHash done = 4;
}

message PieceUploadResponse {
    orders.PieceHash done = 1;
}

// Expected order of messages from uplink:
//   {OrderLimit, Chunk} ->
//   go repeated
//      Order -> (async)
//   go repeated
//      <- PieceDownloadResponse.Chunk
message PieceDownloadRequest {
    // first message to show that we are allowed to upload
    orders.OrderLimit limit = 1;
    // order for downloading
    orders.Order      order = 2;

    // Chunk that we wish to download
    message Chunk {
        int64 offset = 1;
        int64 chunk_size = 2;
    }

    // request for the chunk
    Chunk chunk = 3;
}

message PieceDownloadResponse {
    // Chunk response for download request
    message Chunk {
        int64 offset = 1;
        bytes data = 2;
    }
    Chunk chunk = 1;
    orders.PieceHash hash = 2;
    orders.OrderLimit limit = 3;
}

message PieceDeleteRequest {
    orders.OrderLimit limit = 1;
}

message PieceDeleteResponse {
}

message PieceDeletePieceRequest {
    bytes piece_id = 1 [(gogoproto.customtype) = "PieceID", (gogoproto.nullable) = false];
}

message PieceDeletePieceResponse {
}

message RetainRequest {
    google.protobuf.Timestamp creation_date = 1 [(gogoproto.stdtime) = true, (gogoproto.nullable) = false];
    bytes filter = 2;
}

message RetainResponse {
}

message RestoreTrashRequest {}
message RestoreTrashResponse {}

// PieceHeader is used in piece storage to keep track of piece attributes.
message PieceHeader {
    enum FormatVersion {
        FORMAT_V0 = 0;
        FORMAT_V1 = 1;
    }
    // the storage format version being used for this piece. The piece filename should agree with this.
    // The inclusion of this field is intended to aid repairability when filenames are damaged.
    FormatVersion format_version = 1;
    // content hash of the piece
    bytes hash = 2;
    // timestamp when upload occurred, as given by the "timestamp" field in the original orders.PieceHash
    google.protobuf.Timestamp creation_time = 3 [(gogoproto.stdtime) = true, (gogoproto.nullable) = false];
    // signature from uplink over the original orders.PieceHash (the corresponding PieceHashSigning
    // is reconstructable using the piece id from the piecestore, the piece size from the
    // filesystem (minus the piece header size), and these (hash, upload_time, signature) fields).
    bytes signature = 4;
    // the OrderLimit authorizing storage of this piece, as signed by the satellite and sent by
    // the uplink
    orders.OrderLimit order_limit = 5 [(gogoproto.nullable) = false];
}