# State

### FeePool <a href="#feepool" id="feepool"></a>

All globally tracked parameters for distribution are stored within `FeePool`. Rewards are collected and added to the reward pool and distributed to validators/delegators from here.

Note that the reward pool holds decimal coins (`DecCoins`) to allow for fractions of coins to be received from operations like inflation. When coins are distributed from the pool they are truncated back to `sdk.Coins` which are non-decimal.

* FeePool: `0x00 -> ProtocolBuffer(FeePool)`

```go
// coins with decimal
type DecCoins []DecCoin

type DecCoin struct {
    Amount sdk.Dec
    Denom  string
}
```

```protobuf
// FeePool is the global fee pool for distribution.
message FeePool {
  repeated cosmos.base.v1beta1.DecCoin community_pool = 1
      [(gogoproto.nullable) = false, (gogoproto.castrepeated) = "github.com/cosmos/cosmos-sdk/types.DecCoins"];
}
```

### Validator Distribution <a href="#validator-distribution" id="validator-distribution"></a>

Validator distribution information for the relevant validator is updated each time:

1. delegation amount to a validator is updated,
2. any delegator withdraws from a validator, or
3. the validator withdraws its commission.

* ValidatorDistInfo: `0x02 | ValOperatorAddrLen (1 byte) | ValOperatorAddr -> ProtocolBuffer(validatorDistribution)`

```go
type ValidatorDistInfo struct {
    OperatorAddress     sdk.AccAddress
    SelfBondRewards     sdk.DecCoins
    ValidatorCommission types.ValidatorAccumulatedCommission
}
```

### Delegation Distribution <a href="#delegation-distribution" id="delegation-distribution"></a>

Each delegation distribution only needs to record the height at which it last withdrew fees. Because a delegation must withdraw fees each time it's properties change (aka bonded tokens etc.) its properties will remain constant and the delegator's *accumulation* factor can be calculated passively knowing only the height of the last withdrawal and its current properties.

* DelegationDistInfo: `0x02 | DelegatorAddrLen (1 byte) | DelegatorAddr | ValOperatorAddrLen (1 byte) | ValOperatorAddr -> ProtocolBuffer(delegatorDist)`

```go
type DelegationDistInfo struct {
    WithdrawalHeight int64    // last time this delegation withdrew rewards
}
```

### Params <a href="#params" id="params"></a>

The distribution module stores it's params in state with the prefix of `0x09`, it can be updated with governance or the address with authority.

* Params: `0x09 | ProtocolBuffer(Params)`

```protobuf
// Params defines the set of params for the distribution module.
message Params {
  option (gogoproto.goproto_stringer) = false;
  string community_tax                = 1 [
    (cosmos_proto.scalar)  = "cosmos.Dec",
    (gogoproto.customtype) = "github.com/cosmos/cosmos-sdk/types.Dec",
    (gogoproto.nullable)   = false
  ];
  string base_proposer_reward = 2 [
    (cosmos_proto.scalar)  = "cosmos.Dec",
    (gogoproto.customtype) = "github.com/cosmos/cosmos-sdk/types.Dec",
    (gogoproto.nullable)   = false
  ];
  string bonus_proposer_reward = 3 [
    (cosmos_proto.scalar)  = "cosmos.Dec",
    (gogoproto.customtype) = "github.com/cosmos/cosmos-sdk/types.Dec",
    (gogoproto.nullable)   = false
  ];
  bool withdraw_addr_enabled = 4;
}
```