Merge pull request #2967 from steemit/2962-voting-power-corner-cases

condenser_api: Handle more corner cases in voting_power computation
steemit · Sep 26, 2018 · eed032b · eed032b
2 parents f8402e6 + 8decb36
commit eed032b
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Showing 2 changed files with 38 additions and 10 deletions.
diff --git a/libraries/plugins/apis/condenser_api/condenser_api.cpp b/libraries/plugins/apis/condenser_api/condenser_api.cpp
@@ -2098,6 +2098,41 @@ namespace detail
 
 } // detail
 
+uint16_t api_account_object::_compute_voting_power( const database_api::api_account_object& a )
+{
+   if( a.voting_manabar.last_update_time < STEEM_HARDFORK_0_20_TIME )
+      return (uint16_t) a.voting_manabar.current_mana;
+
+   auto vests = chain::util::get_effective_vesting_shares( a );
+   if( vests <= 0 )
+      return 0;
+
+   //
+   // Let t1 = last_vote_time, t2 = last_update_time
+   // vp_t2 = STEEM_100_PERCENT * current_mana / vests
+   // vp_t1 = vp_t2 - STEEM_100_PERCENT * (t2 - t1) / STEEM_VOTING_MANA_REGENERATION_SECONDS
+   //
+
+   uint32_t t1 = a.last_vote_time.sec_since_epoch();
+   uint32_t t2 = a.voting_manabar.last_update_time;
+   uint64_t dt = (t2 > t1) ? (t2 - t1) : 0;
+   uint64_t vp_dt = STEEM_100_PERCENT * dt / STEEM_VOTING_MANA_REGENERATION_SECONDS;
+
+   uint128_t vp_t2 = STEEM_100_PERCENT;
+   vp_t2 *= a.voting_manabar.current_mana;
+   vp_t2 /= vests;
+
+   uint64_t vp_t2u = vp_t2.to_uint64();
+   if( vp_t2u >= STEEM_100_PERCENT )
+   {
+      wlog( "Truncated vp_t2u to STEEM_100_PERCENT for account ${a}", ("a", a.name) );
+      vp_t2u = STEEM_100_PERCENT;
+   }
+   uint16_t vp_t1 = uint16_t( vp_t2u ) - uint16_t( std::min( vp_t2u, vp_dt ) );
+
+   return vp_t1;
+}
+
 condenser_api::condenser_api()
    : my( new detail::condenser_api_impl() )
 {

diff --git a/libraries/plugins/apis/condenser_api/include/steem/plugins/condenser_api/condenser_api.hpp b/libraries/plugins/apis/condenser_api/include/steem/plugins/condenser_api/condenser_api.hpp
@@ -149,21 +149,14 @@ struct api_account_object
       post_bandwidth( a.post_bandwidth ),
       pending_claimed_accounts( a.pending_claimed_accounts )
    {
-      if( a.voting_manabar.last_update_time < STEEM_HARDFORK_0_20_TIME )
-      {
-         voting_power = (uint16_t) a.voting_manabar.current_mana;
-      }
-      else
-      {
-         auto vests = chain::util::get_effective_vesting_shares( a );
-         voting_power = vests <= 0 ? 0 : (uint16_t)( ( STEEM_100_PERCENT * a.voting_manabar.current_mana ) / vests );
-      }
+      voting_power = _compute_voting_power(a);
       proxied_vsf_votes.insert( proxied_vsf_votes.end(), a.proxied_vsf_votes.begin(), a.proxied_vsf_votes.end() );
    }
 
-
    api_account_object(){}
 
+   uint16_t _compute_voting_power( const database_api::api_account_object& a );
+
    account_id_type   id;
 
    account_name_type name;