From c567bc410ff38da510ba18940d19d5cb6b9a76a8 Mon Sep 17 00:00:00 2001
From: Zahary Karadjov <zahary@gmail.com>
Date: Thu, 7 Feb 2019 22:14:08 +0100
Subject: [PATCH] Use human-readable names for the slot numbers

---
 beacon_chain/beacon_node.nim    | 23 ++++++++++++++---------
 beacon_chain/spec/validator.nim |  2 +-
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/beacon_chain/beacon_node.nim b/beacon_chain/beacon_node.nim
index a19a1cc27..bd8e051c7 100644
--- a/beacon_chain/beacon_node.nim
+++ b/beacon_chain/beacon_node.nim
@@ -30,7 +30,12 @@ const
 
   stateStoragePeriod = EPOCH_LENGTH * 10 # Save states once per this number of slots. TODO: Find a good number.
 
-func shortHash(x: auto): string = ($x)[0..7]
+func humaneSlotNum(s: SlotNumber): SlotNumber =
+  s - GENESIS_SLOT
+
+func shortHash(x: auto): string =
+  ($x)[0..7]
+
 func shortValidatorKey(node: BeaconNode, validatorIdx: int): string =
   ($node.beaconState.validator_registry[validatorIdx].pubkey)[0..7]
 
@@ -182,7 +187,7 @@ proc makeAttestation(node: BeaconNode,
 
   await node.network.broadcast(topicAttestations, attestation)
 
-  info "Attestation sent", slot = slot,
+  info "Attestation sent", slot = humaneSlotNum(slot),
                            shard = shard,
                            validator = shortValidatorKey(node, validator.idx),
                            signature = shortHash(validatorSignature)
@@ -198,7 +203,7 @@ proc proposeBlock(node: BeaconNode,
 
   if node.beaconState.slot + 1 < slot:
     info "Proposing block after slot gap",
-      slot,
+      slot = humaneSlotNum(slot),
       stateSlot = node.beaconState.slot
     for s in node.beaconState.slot + 1 ..< slot:
       let ok = updateState(state, node.headBlockRoot, none[BeaconBlock](), {})
@@ -229,7 +234,7 @@ proc proposeBlock(node: BeaconNode,
 
   await node.network.broadcast(topicBeaconBlocks, newBlock)
 
-  info "Block proposed", slot = slot,
+  info "Block proposed", slot = humaneSlotNum(slot),
                          stateRoot = shortHash(newBlock.state_root),
                          validator = shortValidatorKey(node, validator.idx)
 
@@ -246,7 +251,7 @@ proc scheduleBlockProposal(node: BeaconNode,
 
   info "Scheduling block proposal",
     validator = shortValidatorKey(node, validator.idx),
-    slot,
+    slot = humaneSlotNum(slot),
     fromNow = (at - fastEpochTime()) div 1000
 
   addTimer(node.beaconState.slotStart(slot)) do (x: pointer) {.gcsafe.}:
@@ -329,7 +334,7 @@ proc stateNeedsSaving(s: BeaconState): bool =
 proc processBlocks*(node: BeaconNode) =
   node.network.subscribe(topicBeaconBlocks) do (newBlock: BeaconBlock):
     let stateSlot = node.beaconState.slot
-    info "Block received", slot = newBlock.slot,
+    info "Block received", slot = humaneSlotNum(newBlock.slot),
                            stateRoot = shortHash(newBlock.state_root),
                            stateSlot
 
@@ -343,7 +348,7 @@ proc processBlocks*(node: BeaconNode) =
     var state = node.beaconState
     if stateSlot + 1 < newBlock.slot:
       info "Advancing state past slot gap",
-        blockSlot = newBlock.slot,
+        blockSlot = humaneSlotNum(newBlock.slot),
         stateSlot
       for slot in stateSlot + 1 ..< newBlock.slot:
         let ok = updateState(state, node.headBlockRoot, none[BeaconBlock](), {})
@@ -381,7 +386,7 @@ proc processBlocks*(node: BeaconNode) =
       node.beaconState, a.data, a.aggregation_bitfield).
         mapIt(shortValidatorKey(node, it))
 
-    info "Attestation received", slot = a.data.slot,
+    info "Attestation received", slot = humaneSlotNum(a.data.slot),
                                  shard = a.data.shard,
                                  signature = shortHash(a.aggregate_signature),
                                  participants
@@ -424,7 +429,7 @@ when isMainModule:
 
       info "Starting beacon node",
         slotsSinceFinalization = node.beaconState.slotDistanceFromNow(),
-        stateSlot = node.beaconState.slot
+        stateSlot = humaneSlotNum(node.beaconState.slot)
 
       node.addLocalValidators()
       node.processBlocks()
diff --git a/beacon_chain/spec/validator.nim b/beacon_chain/spec/validator.nim
index 5ff2792a2..4b1e14e62 100644
--- a/beacon_chain/spec/validator.nim
+++ b/beacon_chain/spec/validator.nim
@@ -168,5 +168,5 @@ func get_beacon_proposer_index*(state: BeaconState, slot: uint64): ValidatorInde
   #      because presently, `state.slot += 1` happens before this function
   #      is called - see also testutil.getNextBeaconProposerIndex
   let (first_committee, _) = get_crosslink_committees_at_slot(state, slot)[0]
-  let idx = int(slot mod SlotNumber(first_committee.len))
+  let idx = int(slot mod uint64(first_committee.len))
   first_committee[idx]