syntax = "proto3";
package consensusProto;

option go_package = "consensus/consensusproto";

enum ErrCodes {
    Unexpected = 0;
    LogExists = 1;
    LogNotFound = 2;
    RecordConflict = 3;
    ErrorOffset = 500;
}


message Log {
    bytes id = 1;
    bytes payload = 2;
    repeated RawRecordWithId records = 3;
}

// RawRecord is a proto message containing the payload in bytes, signature of the account who added it and signature of the acceptor
message RawRecord {
    bytes payload = 1;
    bytes signature = 2;
    bytes acceptorIdentity = 3;
    bytes acceptorSignature = 4;
}

// RawRecordWithId is a raw record and the id for convenience
message RawRecordWithId {
    bytes payload = 1;
    string id = 2;
}

// Record is a record containing a data
message Record {
    string prevId = 1;
    bytes identity = 2;
    bytes data = 3;
    int64 timestamp = 4;
}


service Consensus {
    // AddLog adds new log to consensus
    rpc LogAdd(LogAddRequest) returns (Ok);
    // AddRecord adds new record to log
    rpc RecordAdd(RecordAddRequest) returns (RawRecordWithId);
    // WatchLog fetches log and subscribes for a changes
    rpc LogWatch(stream LogWatchRequest) returns (stream LogWatchEvent);
}

message Ok {}

message LogAddRequest {
    Log log = 1;
}

message RecordAddRequest {
    bytes logId = 1;
    RawRecord record = 2;
}

message LogWatchRequest {
    repeated bytes watchIds = 1;
    repeated bytes unwatchIds = 2;
}

message LogWatchEvent {
    bytes logId = 1;
    repeated RawRecordWithId records = 2;
    Err error = 3;
}

message Err {
    ErrCodes error = 1;
}

// LogSyncContentValue provides different types for log sync
message LogSyncContentValue {
    oneof value {
        LogHeadUpdate headUpdate = 1;
        LogFullSyncRequest fullSyncRequest = 2;
        LogFullSyncResponse fullSyncResponse = 3;
    }
}

// LogSyncMessage is a message sent when we are syncing logs
message LogSyncMessage {
    string id = 1;
    string payload = 2;
    LogSyncContentValue content = 3;
}

// LogHeadUpdate is a message sent on consensus log head update
message LogHeadUpdate {
    string head = 1;
    repeated RawRecordWithId records = 2;
}

// LogFullSyncRequest is a message sent when consensus log needs full sync
message LogFullSyncRequest {
    string head = 1;
}

// LogFullSyncResponse is a message sent as a response for a specific full sync
message LogFullSyncResponse {
    string head = 1;
    repeated RawRecordWithId records = 2;
}