// Backupy protobuf v1 — see docs/07-api-contract.md
//
// Messages flowing from the server to the agent over the long-lived WSS
// connection. Each is wrapped in an Envelope (see envelope.proto).

syntax = "proto3";

package backup.v1;

import "backupv1/common.proto";

option go_package = "github.com/backupy/backupy/packages/proto/gen/go/backupv1;backupv1";

// -----------------------------------------------------------------------------
// Register handshake response
// -----------------------------------------------------------------------------

// RegisterAck is the reply to Register. Carries an AgentConfig snapshot so the
// agent can begin work without an extra round-trip.
// See docs/07-api-contract.md §5 (RegisterAck).
message RegisterAck {
  string session_id = 1;
  AgentConfig config = 2;
  uint32 heartbeat_interval_sec = 3;
  string server_time_iso = 4;
}

// -----------------------------------------------------------------------------
// AgentConfig and sub-messages (also reused inside ConfigUpdate)
// -----------------------------------------------------------------------------

// AgentConfig is the full configuration snapshot for an agent.
// See docs/07-api-contract.md §5 (AgentConfig).
message AgentConfig {
  uint64 version = 1;
  repeated Target targets = 2;
  repeated BackupJobSpec jobs = 3;
  repeated HealthCheckSpec health_checks = 4;
  MaintenanceWindow maintenance = 5;
  AdvancedSettings advanced = 6;
}

// Target is a single backup source (database) managed by this agent.
// See docs/07-api-contract.md §5 (Target).
message Target {
  string id = 1;
  DbType type = 2;
  string display_name = 3;
  ConnectionConfig connection = 4;
}

// ConnectionConfig describes how the agent connects to a Target's database.
// See docs/07-api-contract.md §5 (ConnectionConfig).
message ConnectionConfig {
  string host = 1;
  uint32 port = 2;
  string database = 3;
  string username = 4;
  string password_secret_ref = 5;      // reference to encrypted secret in vault
  string container_id = 6;             // populated for DOCKER_EXEC strategy
  ConnectionStrategy strategy = 7;
}

// BackupJobSpec defines a scheduled backup job for one Target.
// See docs/07-api-contract.md §5 (BackupJobSpec).
message BackupJobSpec {
  string id = 1;
  string target_id = 2;
  string cron = 3;                     // cron expression in UTC
  uint32 retention_days = 4;
  string compression = 5;              // "zstd" | "gzip" | "none"
  bool encryption_enabled = 6;
  repeated string pre_hooks = 7;
  repeated string post_hooks = 8;
  RetryPolicy retry = 9;
  uint32 timeout_sec = 10;
}

// HealthCheckSpec defines a single health-check probe.
// See docs/07-api-contract.md §5 (HealthCheckSpec).
message HealthCheckSpec {
  string id = 1;
  string name = 2;
  CheckType type = 3;
  string target = 4;                   // URL or host:port
  uint32 interval_sec = 5;
  uint32 timeout_sec = 6;
  uint32 expected_status = 7;          // expected HTTP status (HTTP/HTTPS only)
}

// -----------------------------------------------------------------------------
// Config push
// -----------------------------------------------------------------------------

// ConfigUpdate replaces the agent's current AgentConfig.
// See docs/07-api-contract.md §5.
message ConfigUpdate {
  AgentConfig config = 1;
}

// -----------------------------------------------------------------------------
// Job control
// -----------------------------------------------------------------------------

// RunBackup tells the agent to execute one backup run for the named job.
// Server pre-issues S3 upload credentials and a KMS-wrapped DEK.
// See docs/07-api-contract.md §5 (RunBackup).
message RunBackup {
  string job_id = 1;
  string run_id = 2;
  bool manual_trigger = 3;
  S3UploadCreds upload_creds = 4;
  bytes encrypted_dek = 5;             // DEK wrapped by KMS
}

// CancelJob requests cancellation of an in-flight job.
// See docs/07-api-contract.md §5 (CancelJob).
message CancelJob {
  string job_id = 1;
}

// RunHealthCheck triggers an immediate, out-of-schedule health-check probe.
// See docs/07-api-contract.md §5 (RunHealthCheck).
message RunHealthCheck {
  string check_id = 1;
}

// -----------------------------------------------------------------------------
// Lifecycle / liveness
// -----------------------------------------------------------------------------

// SelfUpdate asks the agent to upgrade its binary to target_version.
// cosign_signature lets the agent verify the binary before swapping it in.
// See docs/07-api-contract.md §5 (SelfUpdate).
message SelfUpdate {
  string target_version = 1;
  string binary_url = 2;
  string sha256 = 3;
  bytes cosign_signature = 4;
  bool force = 5;
}

// Ping is an application-level keepalive complementing WS-level pings.
// The agent replies with an Ack carrying the same correlation_id.
message Ping {
  uint64 ts_ms = 1;
}