// Copyright (c) 2026 CueCrux Ltd.
// Licensed under the Apache License, Version 2.0.
// See LICENSE in the repository root.

syntax = "proto3";

package corecrux.dataplane.v1;

service CoreCruxDataPlaneV1 {
  rpc AppendBatch(AppendBatchRequest) returns (AppendBatchResponse);
  rpc ReadStream(ReadStreamRequest) returns (stream ReadStreamResponse);
  rpc ReadStreamBatched(ReadStreamBatchedRequest) returns (stream ReadStreamBatchResponse);
  rpc ReadStreamBatchedUnary(ReadStreamBatchedRequest) returns (ReadStreamBatchResponse);
  rpc ReadManyBatchedUnary(ReadManyBatchedRequest) returns (ReadManyBatchedResponse);
  rpc ReadManyFramesBatchedUnary(ReadManyFramesBatchedRequest) returns (ReadManyFramesBatchedResponse);
  rpc ReadFramesBatchedUnary(ReadStreamBatchedRequest) returns (ReadFramesBatchRawResponse);
  rpc ReplaySession(stream ReplaySessionRequest) returns (stream ReplaySessionResponse);
  // Determinism hook: return raw stored frame bytes for a list of locations.
  rpc ReadFrames(ReadFramesRequest) returns (stream ReadFramesResponse);
}

// Phase 8 (optional): large replay export bundles over gRPC streaming.
service CoreCruxExportV1 {
  rpc ExportReceiptBundle(ExportReceiptBundleRequest) returns (stream ExportChunk);
}

message AppendBatchRequest {
  string tenant_id = 1;
  string stream_type = 2;
  string stream_id = 3;
  repeated AppendEvent events = 4;
  uint64 expected_next_seq = 5;
  optional uint64 client_shard_map_version = 6;
}

message AppendEvent {
  string event_id = 1;
  string occurred_at = 2; // RFC3339
  string event_type = 3;
  string content_type = 4;
  bytes payload = 5; // opaque bytes
}

message AppendBatchResponse {
  repeated AppendResult results = 1;
  WriteConfirmation write_confirmation = 2;
}

message WriteConfirmation {
  uint64 commit_seq = 1;
  uint64 segment_id = 2;
  bytes receipt_hash = 3;
  bytes vault_signature = 4;
  string key_id = 5;
  bool unsigned = 6;
  // Present when this append sealed a segment. The signature covers the
  // deterministic segment-seal material bytes, including segment_hash and the
  // previous sealed segment hash when one exists.
  SegmentSealReceipt segment_seal_receipt = 7;
}

message SegmentSealReceipt {
  uint32 shard_id = 1;
  uint64 epoch = 2;
  uint64 segment_seq = 3;
  bytes segment_id = 4;
  bytes segment_hash = 5;
  bool previous_segment_present = 6;
  uint64 previous_segment_seq = 7;
  bytes previous_segment_hash = 8;
  uint64 sealed_at_unix_ns = 9;
  uint64 frame_count = 10;
  bytes material_hash = 11;
  // Ed25519 signature over the deterministic segment-seal material bytes.
  // Empty when signing is unavailable; check unsigned/key_id.
  bytes vault_signature = 12;
  string key_id = 13;
  bool unsigned = 14;
}

message AppendResult {
  enum Status {
    APPENDED = 0;
    DUPLICATE_COMMITTED = 1;
    REJECTED = 2;
    DUPLICATE_IN_BATCH = 3;
  }
  Status status = 1;
  uint64 seq = 2;
  FrameLocation location = 3;
  bytes payload_hash = 4; // 32 bytes (BLAKE3)
  bytes header_hash = 5;  // 32 bytes (BLAKE3)
  uint64 shard_map_version = 6;
  string error_code = 7;
  string error_message = 8;
}

message FrameLocation {
  uint64 shard_id = 1;
  uint64 segment_id = 2;
  uint64 offset = 3;
  uint64 epoch = 4;
}

message ReadStreamRequest {
  string tenant_id = 1;
  string stream_type = 2;
  string stream_id = 3;
  uint64 from_seq_inclusive = 4;
  uint32 max_events = 5;

  enum ReadMode {
    DECODED = 0;
    RAW_FRAMES = 1;
  }
  ReadMode mode = 6;

  // If set > 0, returns the last N events for the stream (ascending seq order).
  // Takes precedence over from_seq_inclusive/max_events.
  uint32 tail_events = 7;
}

message ReadStreamResponse {
  uint64 seq = 1;
  string event_id = 2;
  string occurred_at = 3;
  string ingested_at = 4;
  string event_type = 5;
  string content_type = 6;
  bytes payload = 7;
  FrameLocation location = 8;
}

message ReadStreamBatchedRequest {
  ReadStreamRequest base = 1;
  uint32 max_events_per_message = 2;
  uint32 max_bytes_per_message = 3;
}

message ReadStreamBatchResponse {
  repeated ReadStreamResponse events = 1;
  uint32 event_count = 2;
  uint64 payload_bytes = 3;
  bool eof = 4;
}

message ReadFramesRequest {
  repeated FrameLocation locations = 1;
}

message ReadFramesResponse {
  FrameLocation location = 1;
  bytes frame_bytes = 2; // exact stored bytes
}

message ReadFramesBatchRawResponse {
  repeated FrameLocation locations = 1;
  bytes frames_blob = 2;
  repeated uint32 frame_offsets = 3;
  repeated uint32 frame_lens = 4;
  uint32 frame_count = 5;
  uint64 frame_bytes = 6;
  bool eof = 7;
}

message ReadManyBatchedRequest {
  repeated ReadStreamBatchedRequest reads = 1;
}

message ReadManyBatchedResult {
  uint32 request_index = 1;
  string stream_id = 2;
  ReadStreamBatchResponse batch = 3;
}

message ReadManyBatchedResponse {
  repeated ReadManyBatchedResult results = 1;
  uint32 result_count = 2;
  uint64 payload_bytes = 3;
}

message ReadManyFramesBatchedRequest {
  repeated ReadStreamBatchedRequest reads = 1;
}

message ReadManyFramesBatchedResult {
  uint32 request_index = 1;
  string stream_id = 2;
  ReadFramesBatchRawResponse batch = 3;
}

message ReadManyFramesBatchedResponse {
  repeated ReadManyFramesBatchedResult results = 1;
  uint32 result_count = 2;
  uint64 frame_bytes = 3;
  uint64 frame_count = 4;
}

message ReplaySessionRequest {
  uint32 request_id = 1;
  oneof request {
    ReadManyBatchedRequest decoded_reads = 2;
    ReadManyFramesBatchedRequest frame_reads = 3;
  }
}

message ReplaySessionResponse {
  uint32 request_id = 1;
  oneof response {
    ReadManyBatchedResponse decoded = 2;
    ReadManyFramesBatchedResponse frames = 3;
  }
  bool eof = 4;
  string error_code = 5;
  string error_message = 6;
}

enum ExportFormat {
  EXPORT_FORMAT_ZIP = 0;
  EXPORT_FORMAT_TAR_ZST = 1;
}

enum ExportRedaction {
  EXPORT_REDACTION_TENANT_SAFE = 0;
  EXPORT_REDACTION_NONE = 1;
  EXPORT_REDACTION_METADATA_ONLY = 2;
}

enum ReceiptExportInclude {
  RECEIPT_EXPORT_INCLUDE_BODY = 0;
  RECEIPT_EXPORT_INCLUDE_SIG = 1;
  RECEIPT_EXPORT_INCLUDE_VERIFICATION = 2;
  RECEIPT_EXPORT_INCLUDE_TRACE_SUMMARY = 3;
  RECEIPT_EXPORT_INCLUDE_SUBJECT_LINKS = 4;
  RECEIPT_EXPORT_INCLUDE_LINKED_RECEIPTS = 5;
}

message ExportReceiptBundleRequest {
  string tenant_id = 1;
  string receipt_id = 2;
  ExportFormat format = 3;
  ExportRedaction redaction = 4;
  repeated ReceiptExportInclude include = 5;
}

message ExportChunk {
  uint32 ordinal = 1;
  bytes data = 2;
  bool eof = 3;
  // Only populated on the first chunk.
  string content_type = 4;
  string filename = 5;
}