syntax = "proto3";

import "google/protobuf/wrappers.proto";

// For optional string support
package history;

service History {
    rpc GetSnapshots (SnapshotRequest) returns (RepeatedSnapshotMeta);
    rpc GetInMemoryHistory (SnapshotRequest) returns (HistoryState);
    rpc GetInDiskHistory (SnapshotMeta) returns (HistoryState);
}

message SnapshotRequest {
    string workspace_id = 1;
    string object_id = 2;
    int32 collab_type = 3;
}

// SnapshotMeta represents metadata for a snapshot.
message SnapshotMeta {
    // The unique identifier for the snapshot.
    string oid = 1;
    // The raw binary snapshot data.
    bytes snapshot = 2;
    // The version of the snapshot format.
    // If the version is 1, then use a specific method to decode the snapshot.
    // If the version is 2, then use a different method to decode the snapshot.
    int32 snapshot_version = 3;
    // The creation timestamp of the snapshot.
    int64 created_at = 4;
}

// A container for repeated instances of SnapshotMeta.
message RepeatedSnapshotMeta {
    repeated SnapshotMeta items = 1;  // List of SnapshotMeta items
}


// SnapshotState represents the state of a snapshot, including optional dependency IDs.
message SnapshotState {
    string oid = 1;                        // Unique identifier for the snapshot
    bytes doc_state = 2;                   // The document state as raw binary data
    int32 doc_state_version = 3;           // Version of the document state format
    google.protobuf.StringValue deps_snapshot_id = 4; // Optional dependency snapshot ID
}

message SnapshotInfo {
    HistoryState history_state = 1;
    bytes snapshot = 2;  // Additional field specific to SnapshotInfo representing the snapshot data
}

message HistoryState {
    string object_id = 1;                  // Unique identifier for the object
    bytes doc_state = 2;                   // The document state as raw binary data
    int32 doc_state_version = 3;           // Version of the document state format, with decoding instructions based on version
}