scilla_version 0

import
  BoolUtils
  IntUtils
  ListUtils
  PairUtils

library StakingContract

type Denom =
| Zil
| Token of ByStr20

type Coins =
| Coins of Denom Uint128

type RewardParam =
| RewardParam of Uint128 Uint128 Uint64 Uint64

type Stake =
| Stake of Uint128 Uint64 Uint64 Uint128

type RewardResult =
| RewardResult of Uint128 Uint128

let fee_denom = Uint256 10000

let zil_address = 0x0000000000000000000000000000000000000000

let bool_active = True

let bool_inactive = False

let zil = Zil

let zero = Uint128 0

let zero_i256 = Int256 0

let min_bps = Uint128 1

let max_bps = Uint128 10000

let seconds_per_year = Uint128 31536000

let true = True

let one_msg =
  fun (m : Message) =>
    let e = Nil {(Message)} in
    Cons {(Message)} m e

type Error =
| CodeNotOwner
| ContractFrozenFailure
| Unauthorized
| ContractFrozenFailurePaused
| ContractFrozenFailureNotPaused
| RewardTokenNotFound
| NoStakeFoundBySender
| AmountGreaterThanStakedAmount
| NotAllowedToWithdrawStakeTokens
| InvalidBPSError
| CodeInsufficientFunds

let make_error =
  fun (result : Error) =>
    let result_code =
      match result with
      | CodeNotOwner => Int32 -1
      | ContractFrozenFailure => Int32 -2
      | Unauthorized => Int32 -3
      | ContractFrozenFailurePaused => Int32 -4
      | ContractFrozenFailureNotPaused => Int32 -5
      | RewardTokenNotFound => Int32 -6
      | NoStakeFoundBySender => Int32 -7
      | AmountGreaterThanStakedAmount => Int32 -8
      | NotAllowedToWithdrawStakeTokens => Int32 -9
      | InvalidBPSError => Int32 -10
      | CodeInsufficientFunds => Int32 -11
      end
    in
    { _exception : "Error"; code : result_code }

let get_value =
  fun (var : Option Uint128) =>
    match var with
    | Some v => v
    | None => zero
    end

let uint64_to_uint128 : Uint64 -> Uint128 =
  fun (x : Uint64) =>
    let ox128 = builtin to_uint128 x in
    match ox128 with
    | None => let zero = Uint128 0 in builtin div zero zero
    | Some x128 => x128
    end

let int256_to_uint128 : Int256 -> Uint128 =
  fun (x : Int256) =>
    let ox128 = builtin to_uint128 x in
    match ox128 with
    | None => let zero = Uint128 0 in builtin div zero zero
    | Some x128 => x128
    end

let is_admin_or_owner : (Map ByStr20 Bool) -> ByStr20 -> ByStr20 -> Bool =
  fun (administrators : Map ByStr20 Bool) =>
    fun (owner : ByStr20) =>
      fun (sender : ByStr20) =>
        let is_admin = builtin contains administrators sender in
        let is_owner = builtin eq sender owner in
        let allowed = orb is_admin is_owner in
        match allowed with
        | True => True
        | False => False
        end

let update_reward_param : RewardParam -> Uint64 -> RewardParam =
  fun (reward_param : RewardParam) =>
    fun (current_timestamp : Uint64) =>
      match reward_param with
      | RewardParam apr treasury_fee start_timestamp end_timestamp =>
        let zero_timestamp = Uint64 0 in
        let is_eq_timestamp_zero = builtin eq end_timestamp zero_timestamp in
        match is_eq_timestamp_zero with
        | True => RewardParam apr treasury_fee start_timestamp current_timestamp
        | False => RewardParam apr treasury_fee start_timestamp end_timestamp
        end
      end

let update_all_reward_params :
  forall 'A. (List RewardParam) -> Uint64 -> List RewardParam =
  tfun 'A =>
    fun (l : List RewardParam) =>
      fun (current_timestamp : Uint64) =>
        let foldl = @list_foldl (RewardParam) (List RewardParam) in
        let init = Nil {(RewardParam)} in
        let iter =
          fun (reward_params_list : List RewardParam) =>
            fun (reward_param : RewardParam) =>
              let updated_reward_param =
                update_reward_param reward_param current_timestamp
              in
              Cons {(RewardParam)} updated_reward_param reward_params_list
        in
        foldl iter init l

let is_timestamp_let : Uint64 -> Uint64 -> Bool =
  fun (ts1 : Uint64) =>
    fun (ts2 : Uint64) =>
      let is_ts1_le_ts2 = uint64_lt ts1 ts2 in
      let is_ts1_eq_ts2 = builtin eq ts1 ts2 in
      orb is_ts1_le_ts2 is_ts1_eq_ts2

let get_time_difference : Uint128 -> Uint64 -> RewardParam -> Uint64 -> Uint64 =
  fun (staked_amount : Uint128) =>
    fun (staked_timestamp : Uint64) =>
      fun (reward_param : RewardParam) =>
        fun (current_timestamp : Uint64) =>
          match reward_param with
          | RewardParam apr treasury_fee start_timestamp end_timestamp =>
            let zero_timestamp = Uint64 0 in
            let microseconds = Uint64 1000000 in
            let is_eq_block_zero = builtin eq end_timestamp zero_timestamp in
            match is_eq_block_zero with
            | True =>
              let is_staked_timestamp_leq_start_timestamp =
                is_timestamp_let staked_timestamp start_timestamp
              in
              match is_staked_timestamp_leq_start_timestamp with
              | True =>
                let diff = builtin sub current_timestamp start_timestamp in
                builtin div diff microseconds
              | False =>
                let diff = builtin sub current_timestamp staked_timestamp in
                builtin div diff microseconds
              end
            | False =>
              let is_staked_timestamp_leq_end_timestamp =
                is_timestamp_let staked_timestamp end_timestamp
              in
              match is_staked_timestamp_leq_end_timestamp with
              | True =>
                let is_staked_timestamp_leq_start_timestamp =
                  is_timestamp_let staked_timestamp start_timestamp
                in
                match is_staked_timestamp_leq_start_timestamp with
                | True =>
                  let diff = builtin sub end_timestamp start_timestamp in
                  builtin div diff microseconds
                | False =>
                  let diff = builtin sub end_timestamp staked_timestamp in
                  builtin div diff microseconds
                end
              | False => zero_timestamp
              end
            end
          end

let uint128_to_uint256 : Uint128 -> Uint256 =
  fun (x : Uint128) =>
    let ox256 = builtin to_uint256 x in
    match ox256 with
    | None => let zero = Uint256 0 in builtin div zero zero
    | Some x256 => x256
    end

let muldiv : Uint128 -> Uint128 -> Uint128 -> Uint128 -> Uint256 -> Uint128 =
  fun (w : Uint128) =>
    fun (x : Uint128) =>
      fun (y : Uint128) =>
        fun (z : Uint128) =>
          fun (f : Uint256) =>
            let w256 = uint128_to_uint256 w in
            let x256 = uint128_to_uint256 x in
            let y256 = uint128_to_uint256 y in
            let z256 = uint128_to_uint256 z in
            let w_mul_x256 = builtin mul w256 x256 in
            let w_mul_x_mul_y256 = builtin mul w_mul_x256 y256 in
            let w_mul_x_mul_y256_div_z256 = builtin div w_mul_x_mul_y256 z256 in
            let res256 = builtin div w_mul_x_mul_y256_div_z256 f in
            let ores128 = builtin to_uint128 res256 in
            match ores128 with
            | None =>
              let max_uint128 = Uint128 340282366920938463463374607431768211455
              in
              let fourtytwo128 = Uint128 42 in
              builtin mul max_uint128 fourtytwo128
            | Some res128 => res128
            end

let calculate_treasury_fee_amt : Uint128 -> Uint256 -> Uint128 -> Uint128 =
  fun (treasury_fee : Uint128) =>
    fun (fee_denom : Uint256) =>
      fun (amount : Uint128) =>
        let tf256 = uint128_to_uint256 treasury_fee in
        let amt256 = uint128_to_uint256 amount in
        let tf_mul_amt = builtin mul tf256 amt256 in
        let res256 = builtin div tf_mul_amt fee_denom in
        let ores128 = builtin to_uint128 res256 in
        match ores128 with
        | None =>
          let max_uint128 = Uint128 340282366920938463463374607431768211455 in
          let fourtytwo128 = Uint128 42 in
          builtin mul max_uint128 fourtytwo128
        | Some res128 => res128
        end

let calculate_rewards :
  forall 'A.
    (List RewardParam) ->
    Uint128 ->
    Uint64 ->
    Uint64 ->
    Uint128 ->
    Uint256 ->
    RewardResult =
  tfun 'A =>
    fun (l : List RewardParam) =>
      fun (staked_amount : Uint128) =>
        fun (staked_timestamp : Uint64) =>
          fun (current_timestamp : Uint64) =>
            fun (seconds_per_year : Uint128) =>
              fun (fee_denom : Uint256) =>
                let foldl = @list_foldl (RewardParam) (RewardResult) in
                let init = RewardResult zero zero in
                let iter =
                  fun (rewards : RewardResult) =>
                    fun (reward_param : RewardParam) =>
                      match reward_param with
                      | RewardParam apr treasury_fee start_block end_block =>
                        let time_diff_ui64 =
                          get_time_difference
                            staked_amount staked_timestamp reward_param current_timestamp
                        in
                        let time_diff = uint64_to_uint128 time_diff_ui64 in
                        let res_total =
                          muldiv
                            staked_amount time_diff apr seconds_per_year fee_denom
                        in
                        let treasury_fee_amt =
                          calculate_treasury_fee_amt
                            treasury_fee fee_denom res_total
                        in
                        let res = builtin sub res_total treasury_fee_amt in
                        match rewards with
                        | RewardResult curr_rewards_count curr_treasury_fee_amt =>
                          let new_rewards_count =
                            builtin add curr_rewards_count res
                          in
                          let new_treasury_fee_amt =
                            builtin add curr_treasury_fee_amt treasury_fee_amt
                          in
                          RewardResult new_rewards_count new_treasury_fee_amt
                        end
                      end
                in
                foldl iter init l

let portion =
  fun (amount : Uint128) =>
    fun (bps : Uint128) =>
      let max_bps = Uint128 10000 in
      let x = builtin div max_bps bps in
      let result = builtin div amount x in
      result

let option_value =
  tfun 'A =>
    fun (default : 'A) =>
      fun (maybe_val : Option 'A) =>
        match maybe_val with
        | Some v => v
        | None => default
        end

let option_timestamp = @option_value (Uint64)

let get_prev_bnum =
  fun (cur_blk : BNum) =>
    let one_bnum = BNum 1 in
    let zero_block = BNum 0 in
    let prev_block = builtin bsub cur_blk one_bnum in
    let prev_block_uint128 = int256_to_uint128 prev_block in
    builtin badd zero_block prev_block_uint128


contract StakingContract
  (
    initial_owner : ByStr20,
    initial_staking_token_address :
      ByStr20 with contract
        field allowances : Map ByStr20 (Map ByStr20 Uint128),
        field balances : Map ByStr20 Uint128,
        field total_supply : Uint128
      end
  )


field owner : ByStr20 = initial_owner

field staking_token_address : ByStr20 = initial_staking_token_address

field pending_owner : ByStr20 = zil_address

field paused : Bool = True

field reward_pairs : Map ByStr20 (List RewardParam) =
  Emp (ByStr20) (List RewardParam)

field stakes : Map ByStr20 Stake = Emp (ByStr20) (Stake)

field rewards : Map ByStr20 (Map ByStr20 Uint128) =
  Emp (ByStr20) (Map ByStr20 Uint128)

field administrators : Map ByStr20 Bool = Emp (ByStr20) (Bool)

field treasury_balances : Map ByStr20 Uint128 = Emp (ByStr20) (Uint128)

field treasury_fees_address : ByStr20 = initial_owner

field penalty_fee_balances : Uint128 = zero

field total_staked_amount : Uint128 = zero

procedure Throw (err : Error)
  e = make_error err;
  throw e
end

procedure EnsureContractIsNotPaused ()
  paused_tmp <- paused;
  match paused_tmp with
  | False =>
  | True =>
    err = ContractFrozenFailurePaused;
    Throw err
  end
end

procedure EnsureContractIsPaused ()
  paused_tmp <- paused;
  match paused_tmp with
  | False =>
    err = ContractFrozenFailureNotPaused;
    Throw err
  | True =>
  end
end

procedure EnsureSenderIsOwner (initiator : ByStr20)
  current_owner <- owner;
  is_owner = builtin eq initiator current_owner;
  match is_owner with
  | True =>
  | False =>
    err = CodeNotOwner;
    Throw err
  end
end

procedure EnsureSenderIsAdminOrOwner (address : ByStr20)
  admins <- administrators;
  current_owner <- owner;
  check_allowed = is_admin_or_owner admins current_owner address;
  match check_allowed with
  | True =>
  | False =>
    err = Unauthorized;
    Throw err
  end
end

procedure EnsureNotStakeToken (address : ByStr20)
  stake_token_addr <- staking_token_address;
  is_same = builtin eq address stake_token_addr;
  match is_same with
  | True =>
    err = NotAllowedToWithdrawStakeTokens;
    Throw err
  | False =>
  end
end

procedure RequireValidBPS (val_bps : Uint128)
  is_gte_min = uint128_ge val_bps min_bps;
  is_lte_max = uint128_le val_bps max_bps;
  is_valid = andb is_gte_min is_lte_max;
  match is_valid with
  | True =>
  | False =>
    error = InvalidBPSError;
    Throw error
  end
end

procedure Send (coins : Coins, to_address : ByStr20)
  match coins with
  | Coins denom amount =>
    match denom with
    | Zil =>
      msg = { _tag : "AddFunds"; _recipient : to_address; _amount : amount };
      msgs = one_msg msg;
      send msgs
    | Token token =>
      msg_to_token =
        {
          _tag : "Transfer";
          _recipient : token;
          _amount : zero;
          to : to_address;
          amount : amount
        };
      msgs = one_msg msg_to_token;
      send msgs
    end
  end
end

procedure Receive (coins : Coins, initiator : ByStr20)
  EnsureContractIsNotPaused;
  match coins with
  | Coins denom amount =>
    match denom with
    | Zil =>
      needs_refund = uint128_gt _amount amount;
      accept;
      match needs_refund with
      | True =>
        refund =
          let refund_amount = builtin sub _amount amount in
          Coins zil refund_amount;
        Send refund initiator
      | False =>
      end
    | Token token =>
      msg_to_token =
        {
          _tag : "TransferFrom";
          _recipient : token;
          _amount : zero;
          from : initiator;
          to : _this_address;
          amount : amount
        };
      msgs = one_msg msg_to_token;
      send msgs
    end
  end
end

procedure UpdateTreasuryFeeAmount (reward_token : ByStr20, amount : Uint128)
  is_amount_eq_zero = builtin eq amount zero;
  match is_amount_eq_zero with
  | False =>
    maybe_treasury_fee_amount <- treasury_balances[reward_token];
    match maybe_treasury_fee_amount with
    | Some curr_amount =>
      new_amount = builtin add curr_amount amount;
      treasury_balances[reward_token] := new_amount;
      e =
        {
          _eventname : "UpdateTreasuryFeeAmountWithPreviousValueSuccess";
          sender : _origin;
          reward_token : reward_token;
          old_amount : curr_amount;
          new_amount : new_amount;
          difference : amount
        };
      event e
    | None =>
      treasury_balances[reward_token] := amount;
      e =
        {
          _eventname : "UpdateRewardsAmountFirstClaimSuccess";
          sender : _origin;
          reward_token : reward_token;
          new_amount : amount
        };
      event e
    end
  | True =>
  end
end

procedure UpdateRewardsAmount (reward_token : ByStr20, amount : Uint128)
  is_amount_eq_zero = builtin eq amount zero;
  match is_amount_eq_zero with
  | False =>
    maybe_rewards_amount <- rewards[reward_token][_origin];
    match maybe_rewards_amount with
    | Some curr_amount =>
      new_amount = builtin add curr_amount amount;
      rewards[reward_token][_origin] := new_amount;
      e =
        {
          _eventname : "UpdateRewardsAmountWithPreviousValueSuccess";
          sender : _origin;
          reward_token : reward_token;
          old_amount : curr_amount;
          new_amount : new_amount;
          difference : amount
        };
      event e
    | None =>
      rewards[reward_token][_origin] := amount;
      e =
        {
          _eventname : "UpdateRewardsAmountFirstClaimSuccess";
          sender : _origin;
          reward_token : reward_token;
          new_amount : amount
        };
      event e
    end
  | True =>
  end
end

procedure UpdateRewards (reward_token : ByStr20, reward_res : RewardResult)
  match reward_res with
  | RewardResult total_rewards treasury_fee_amt =>
    UpdateRewardsAmount reward_token total_rewards;
    UpdateTreasuryFeeAmount reward_token treasury_fee_amt
  end
end

procedure DoClaimRewards (reward_pair : Pair ByStr20 (List RewardParam))
  maybe_stake <- stakes[_origin];
  current_block <-& BLOCKNUMBER;
  prev_block = get_prev_bnum current_block;
  ts <-& TIMESTAMP(prev_block);
  zero_64 = Uint64 0;
  current_timestamp = option_timestamp zero_64 ts;
  match maybe_stake with
  | Some stake =>
    match stake with
    | Stake staked_amount staked_timestamp end_block penalty_fee =>
      reward_token_address =
        let fst_reward_token_address = @fst (ByStr20) (List RewardParam) in
        fst_reward_token_address reward_pair;
      reward_param_list =
        let snd_reward_param_list = @snd (ByStr20) (List RewardParam) in
        snd_reward_param_list reward_pair;
      calculate_rewards_fun = @calculate_rewards (List RewardParam);
      maybe_running_interest_amount <- rewards[reward_token_address][_origin];
      match maybe_running_interest_amount with
      | Some running_interest_amount =>
        total_amount = builtin add staked_amount running_interest_amount;
        reward_res =
          calculate_rewards_fun
            reward_param_list total_amount staked_timestamp current_timestamp seconds_per_year fee_denom;
        UpdateRewards reward_token_address reward_res
      | None =>
        reward_res =
          calculate_rewards_fun
            reward_param_list staked_amount staked_timestamp current_timestamp seconds_per_year fee_denom;
        UpdateRewards reward_token_address reward_res
      end
    end
  | None =>
    err = NoStakeFoundBySender;
    Throw err
  end
end

procedure DoRemoveRewardToken (reward_token_address : ByStr20)
  current_block <-& BLOCKNUMBER;
  prev_block = get_prev_bnum current_block;
  ts <-& TIMESTAMP(prev_block);
  zero_64 = Uint64 0;
  current_timestamp = option_timestamp zero_64 ts;
  maybe_reward_params_list <- reward_pairs[reward_token_address];
  match maybe_reward_params_list with
  | Some reward_params_list =>
    update_all_reward_params_fun = @update_all_reward_params (List RewardParam);
    updated_reward_params_list =
      update_all_reward_params_fun reward_params_list current_timestamp;
    reward_pairs[reward_token_address] := updated_reward_params_list
  | None =>
    err = RewardTokenNotFound;
    Throw err
  end
end

procedure DoRemoveAllRewardTokens
  (reward_pair : Pair ByStr20 (List RewardParam))
  reward_token_address =
    let fst_reward_token_address = @fst (ByStr20) (List RewardParam) in
    fst_reward_token_address reward_pair;
  DoRemoveRewardToken reward_token_address
end

procedure DoWithdrawRewards (reward_pair : Pair ByStr20 (List RewardParam))
  reward_token_address =
    let fst_reward_token_address = @fst (ByStr20) (List RewardParam) in
    fst_reward_token_address reward_pair;
  maybe_reward_token_amt <- rewards[reward_token_address][_origin];
  match maybe_reward_token_amt with
  | Some reward_token_amt =>
    is_zil = builtin eq reward_token_address zil_address;
    match is_zil with
    | True =>
      stake_token_addr <- staking_token_address;
      is_staked_token_same_as_withdraw =
        builtin eq reward_token_address stake_token_addr;
      match is_staked_token_same_as_withdraw with
      | True =>
        balances <- _balance;
        total_staked <- total_staked_amount;
        available_bal_to_withdraw = builtin sub balances total_staked;
        is_valid_withdrawal_amount =
          uint128_le reward_token_amt available_bal_to_withdraw;
        match is_valid_withdrawal_amount with
        | True =>
          zils_out = Coins zil reward_token_amt;
          Send zils_out _origin
        | False =>
          err = CodeInsufficientFunds;
          Throw err
        end
      | False =>
        zils_out = Coins zil reward_token_amt;
        Send zils_out _origin
      end
    | False =>
      stake_token_addr <- staking_token_address;
      is_staked_token_same_as_withdraw =
        builtin eq reward_token_address stake_token_addr;
      match is_staked_token_same_as_withdraw with
      | True =>
        balances <-& initial_staking_token_address.balances[_this_address];
        contract_balance = get_value balances;
        total_staked <- total_staked_amount;
        available_bal_to_withdraw = builtin sub contract_balance total_staked;
        is_valid_withdrawal_amount =
          uint128_le reward_token_amt available_bal_to_withdraw;
        match is_valid_withdrawal_amount with
        | True =>
          reward_token = Token reward_token_address;
          tokens_out = Coins reward_token reward_token_amt;
          Send tokens_out _origin
        | False =>
          err = CodeInsufficientFunds;
          Throw err
        end
      | False =>
        reward_token = Token reward_token_address;
        tokens_out = Coins reward_token reward_token_amt;
        Send tokens_out _origin
      end
    end;
    delete rewards[reward_token_address][_origin];
    e =
      {
        _eventname : "WithdrawRewardsSuccess";
        sender : _origin;
        reward_token : reward_token_address;
        amount : reward_token_amt
      };
    event e
  | None =>
    e =
      {
        _eventname : "WithdrawRewardsSuccess";
        sender : _origin;
        reward_token : reward_token_address;
        amount : zero
      };
    event e
  end
end

transition AddStake
  (amount : Uint128, expiration_time : Uint64, penalty_fee_bps : Uint128)
  current_block <-& BLOCKNUMBER;
  prev_block = get_prev_bnum current_block;
  ts <-& TIMESTAMP(prev_block);
  zero_64 = Uint64 0;
  current_timestamp = option_timestamp zero_64 ts;
  maybe_stake <- stakes[_origin];
  RequireValidBPS penalty_fee_bps;
  token_address <- staking_token_address;
  token = Token token_address;
  tokens_in = Coins token amount;
  Receive tokens_in _origin;
  match maybe_stake with
  | Some stake =>
    match stake with
    | Stake staked_amount timestamp end_timestamp penalty_fee =>
      curent_reward_pairs <- reward_pairs;
      rewards_list = builtin to_list curent_reward_pairs;
      forall rewards_list DoClaimRewards;
      total_amount = builtin add staked_amount amount;
      updated_stake =
        Stake total_amount current_timestamp end_timestamp penalty_fee;
      stakes[_origin] := updated_stake;
      total_staked <- total_staked_amount;
      new_total_staked = builtin add total_staked amount;
      total_staked_amount := new_total_staked
    end
  | None =>
    stake = Stake amount current_timestamp expiration_time penalty_fee_bps;
    stakes[_origin] := stake;
    total_staked <- total_staked_amount;
    new_total_staked = builtin add total_staked amount;
    total_staked_amount := new_total_staked
  end
end

transition RemoveStake (amount : Uint128)
  current_block <-& BLOCKNUMBER;
  prev_block = get_prev_bnum current_block;
  ts <-& TIMESTAMP(prev_block);
  zero_64 = Uint64 0;
  current_timestamp = option_timestamp zero_64 ts;
  maybe_stake <- stakes[_origin];
  match maybe_stake with
  | Some (Stake staked_amount staked_timestamp end_timestamp penalty_fee) =>
    is_amount_less_than_staked_amount = builtin lt amount staked_amount;
    is_amount_equal_to_staked_amount = builtin eq amount staked_amount;
    is_amount_less_or_equal_to_staked_amount =
      orb is_amount_less_than_staked_amount is_amount_equal_to_staked_amount;
    match is_amount_less_or_equal_to_staked_amount with
    | True =>
      curent_reward_pairs <- reward_pairs;
      rewards_list = builtin to_list curent_reward_pairs;
      forall rewards_list DoClaimRewards;
      is_lt_curr_timestamp = uint64_lt current_timestamp end_timestamp;
      match is_lt_curr_timestamp with
      | True =>
        fee_bps = portion amount penalty_fee;
        new_amount = builtin sub amount fee_bps;
        penalty_fee_amount <- penalty_fee_balances;
        new_penalty_fee_amount = builtin add penalty_fee_amount fee_bps;
        penalty_fee_balances := new_penalty_fee_amount;
        token_address <- staking_token_address;
        staked_token = Token token_address;
        output = Coins staked_token new_amount;
        Send output _origin
      | False =>
        token_address <- staking_token_address;
        staked_token = Token token_address;
        output = Coins staked_token amount;
        Send output _origin
      end;
      remaining_amount = builtin sub staked_amount amount;
      is_remaining_amount_eq_zero = builtin eq remaining_amount zero;
      match is_remaining_amount_eq_zero with
      | True => delete stakes[_origin]
      | False =>
        updated_stake =
          Stake remaining_amount current_timestamp end_timestamp penalty_fee;
        stakes[_origin] := updated_stake
      end;
      total_staked <- total_staked_amount;
      new_total_staked = builtin sub total_staked amount;
      total_staked_amount := new_total_staked
    | False =>
      err = AmountGreaterThanStakedAmount;
      Throw err
    end
  | None =>
    err = NoStakeFoundBySender;
    Throw err
  end
end

transition ClaimRewards ()
  current_block <-& BLOCKNUMBER;
  prev_block = get_prev_bnum current_block;
  ts <-& TIMESTAMP(prev_block);
  zero_64 = Uint64 0;
  current_timestamp = option_timestamp zero_64 ts;
  maybe_stake <- stakes[_origin];
  match maybe_stake with
  | Some (Stake staked_amount staked_timestamp end_timestamp penalty_fee) =>
    curent_reward_pairs <- reward_pairs;
    rewards_list = builtin to_list curent_reward_pairs;
    forall rewards_list DoClaimRewards;
    forall rewards_list DoWithdrawRewards;
    updated_stake =
      Stake staked_amount current_timestamp end_timestamp penalty_fee;
    stakes[_origin] := updated_stake
  | None =>
    curent_reward_pairs <- reward_pairs;
    rewards_list = builtin to_list curent_reward_pairs;
    forall rewards_list DoWithdrawRewards
  end
end

transition AddRewardToken
  (reward_token_address : ByStr20, apr : Uint128, treasury_fee : Uint128)
  EnsureSenderIsAdminOrOwner _sender;
  current_block <-& BLOCKNUMBER;
  prev_block = get_prev_bnum current_block;
  ts <-& TIMESTAMP(prev_block);
  zero_64 = Uint64 0;
  current_timestamp = option_timestamp zero_64 ts;
  end_timestamp = Uint64 0;
  reward_param = RewardParam apr treasury_fee current_timestamp end_timestamp;
  maybe_reward_params_list <- reward_pairs[reward_token_address];
  match maybe_reward_params_list with
  | Some reward_params_list =>
    update_all_reward_params_fun = @update_all_reward_params (List RewardParam);
    updated_reward_params_list =
      update_all_reward_params_fun reward_params_list current_timestamp;
    reward_params_list_new =
      Cons {(RewardParam)} reward_param updated_reward_params_list;
    reward_pairs[reward_token_address] := reward_params_list_new
  | None =>
    reward_params_list = Nil {(RewardParam)};
    reward_params_list_new =
      Cons {(RewardParam)} reward_param reward_params_list;
    reward_pairs[reward_token_address] := reward_params_list_new
  end
end

transition RemoveRewardToken (reward_token_address : ByStr20)
  EnsureSenderIsAdminOrOwner _sender;
  DoRemoveRewardToken reward_token_address
end

transition RemoveAllRewardTokens ()
  EnsureSenderIsAdminOrOwner _sender;
  curent_reward_pairs <- reward_pairs;
  rewards_list = builtin to_list curent_reward_pairs;
  forall rewards_list DoRemoveAllRewardTokens
end

transition Pause ()
  EnsureSenderIsAdminOrOwner _sender;
  paused := bool_active
end

transition UnPause ()
  EnsureSenderIsAdminOrOwner _sender;
  paused := bool_inactive
end

transition AddAdmin (address : ByStr20)
  EnsureSenderIsOwner _sender;
  administrators[address] := true;
  e = { _eventname : "AddAdminSuccess"; addressAdded : address };
  event e
end

transition RemoveAdmin (address : ByStr20)
  EnsureSenderIsOwner _sender;
  delete administrators[address];
  e = { _eventname : "RemoveAdminSuccess"; address : address };
  event e
end

transition TransferOwnership (new_owner : ByStr20)
  EnsureSenderIsOwner _sender;
  existing_owner <- owner;
  new_owner_is_existing_owner = builtin eq new_owner existing_owner;
  match new_owner_is_existing_owner with
  | True =>
    e = { _exception : "ExistingOwner" };
    throw e
  | False => pending_owner := new_owner
  end
end

transition AcceptPendingOwnership ()
  new_owner <- pending_owner;
  sender_is_pending_owner = builtin eq _sender new_owner;
  match sender_is_pending_owner with
  | False =>
    e = { _exception : "InvalidSender" };
    throw e
  | True =>
    owner := new_owner;
    pending_owner := zil_address;
    e = { _eventname : "OwnershipTransferred"; owner : new_owner };
    event e
  end
end

transition WithdrawTokens (token_address : ByStr20, token_amount : Uint128)
  EnsureSenderIsOwner _sender;
  stake_token_addr <- staking_token_address;
  is_staked_token_same_as_withdraw = builtin eq token_address stake_token_addr;
  match is_staked_token_same_as_withdraw with
  | True =>
    balances <-& initial_staking_token_address.balances[_this_address];
    contract_balance = get_value balances;
    total_staked <- total_staked_amount;
    available_bal_to_withdraw = builtin sub contract_balance total_staked;
    is_valid_withdrawal_amount =
      uint128_le token_amount available_bal_to_withdraw;
    match is_valid_withdrawal_amount with
    | True =>
      reward_token = Token token_address;
      tokens_out = Coins reward_token token_amount;
      Send tokens_out _sender
    | False =>
      err = CodeInsufficientFunds;
      Throw err
    end
  | False =>
    reward_token = Token token_address;
    tokens_out = Coins reward_token token_amount;
    Send tokens_out _sender
  end
end

transition WithdrawZils (zil_amount : Uint128)
  EnsureSenderIsAdminOrOwner _sender;
  zils_out = Coins zil zil_amount;
  Send zils_out _sender
end

transition Deposit (token_address : ByStr20, token_amount : Uint128)
  EnsureSenderIsAdminOrOwner _sender;
  token = Token token_address;
  tokens_in = Coins token token_amount;
  Receive tokens_in _sender
end

transition TransferFromSuccessCallBack
  (initiator : ByStr20, sender : ByStr20, recipient : ByStr20, amount : Uint128)

end

transition TransferSuccessCallBack
  (sender : ByStr20, recipient : ByStr20, amount : Uint128)

end

transition RecipientAcceptTransferFrom
  (initiator : ByStr20, sender : ByStr20, recipient : ByStr20, amount : Uint128)
  is_valid_transfer_to_self =
    let self_triggered = builtin eq initiator _this_address in
    let is_transfer_to_self = builtin eq recipient _this_address in
    andb self_triggered is_transfer_to_self;
  match is_valid_transfer_to_self with
  | False =>
    e = { _exception : "InvalidInvocation" };
    throw e
  | True =>
  end
end

transition AddFunds ()
  accept
end

transition RecipientAcceptTransfer
  (sender : ByStr20, recipient : ByStr20, amount : Uint128)

end