syntax = "proto3";

package ethereum.eth.dbval;

option go_package = "github.com/prysmaticlabs/prysm/v5/proto/dbval;dbval";

// BackfillStatus is a value used to keep track of the progress of the process of backfilling blocks leading up to
// the origin block used to checkpoint sync a node. There is only one BackfillStatus value in the database.
message BackfillStatus {
    // low_slot is the slot of the last block that backfill will attempt to download and import.
    // This is determined by MIN_EPOCHS_FOR_BLOCK_REQUESTS, or by a user-specified override.
    uint64 low_slot = 1;
    // low_root is the root of the last block that backfill will attempt to download and import.
    bytes low_root = 2;
    // low_parent_root is the parent_root of the block at low_root. This enables the backfill service to check
    // that a block is the direct ancestor of the block for low_root without an additional db lookup.
    bytes low_parent_root = 3;
    // origin_slot is the slot of the origin block, which is the block used to initiate a checkpoint sync.
    // Backfill uses the origin block as the reference point to determine canonical ancestors.
    uint64 origin_slot = 4;
    // origin_root is the root of the origin block.
    bytes origin_root = 6;
}