pool.fc

;; The validator has his own wallet in the masterchain, on which he holds his own coins for operating.
;; From this wallet he sends commands to this nominator pool (mostly `new_stake`, `update_validator_set` and `recover_stake`).
;; Register/vote_for complaints and register/vote_for config proposals are sent from validator's wallet.
;;
;; Pool contract must be in masterchain.
;; Nominators' wallets must be in the basechain.
;; The validator in most cases have two pools (for even and odd validation rounds).

int op::new_stake() asm "0x4e73744b PUSHINT"; ;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L621
int op::new_stake_error() asm "0xee6f454c PUSHINT"; ;; return_stake https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L169
int op::new_stake_ok() asm "0xf374484c PUSHINT"; ;; send_confirmation https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L173

int op::recover_stake() asm "0x47657424 PUSHINT"; ;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L625
int op::recover_stake_error() asm "0xfffffffe PUSHINT"; ;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L407
int op::recover_stake_ok() asm "0xf96f7324 PUSHINT"; ;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L426

int ADDR_SIZE() asm "256 PUSHINT";
int BOUNCEABLE() asm "0x18 PUSHINT";
int NON_BOUNCEABLE() asm "0x10 PUSHINT";
int SEND_MODE_PAY_FEE_SEPARATELY() asm "1 PUSHINT"; ;; means that the sender wants to pay transfer fees separately
int SEND_MODE_IGNORE_ERRORS() asm "2 PUSHINT"; ;; means that any errors arising while processing this message during the action phase should be ignored
int SEND_MODE_REMAINING_AMOUNT() asm "64 PUSHINT"; ;; is used for messages that carry all the remaining value of the inbound message in addition to the value initially indicated in the new message
int ONE_TON() asm "1000000000 PUSHINT";
int MIN_TONS_FOR_STORAGE() asm "10000000000 PUSHINT"; ;; 10 TON
int DEPOSIT_PROCESSING_FEE() asm "1000000000 PUSHINT"; ;; 1 TON
int MIN_STAKE_TO_SEND() asm "500000000000 PUSHINT"; ;; 500 TON
int VOTES_LIFETIME() asm "2592000 PUSHINT"; ;; 30 days

int binary_log_ceil(int x) asm "UBITSIZE";

;; hex parse same with bridge https://github.com/ton-blockchain/bridge-func/blob/d03dbdbe9236e01efe7f5d344831bf770ac4c613/func/text_utils.fc
(slice, int) ~load_hex_symbol(slice comment) {
    int n = comment~load_uint(8);
    n = n - 48;
    throw_unless(329, n >= 0);
    if (n < 10) {
        return (comment, (n));
    }
    n = n - 7;
    throw_unless(329, n >= 0);
    if (n < 16) {
        return (comment, (n));
    }
    n = n - 32;
    throw_unless(329, (n >= 0) & (n < 16));
    return (comment, n);
}

(slice, int) ~load_text_hex_number(slice comment, int byte_length) {
    int current_slice_length = comment.slice_bits() / 8;
    int result = 0;
    int counter = 0;
    repeat (2 * byte_length) {
        result = result * 16 + comment~load_hex_symbol();
        counter = counter + 1;
        if (counter == current_slice_length) {
            if (comment.slice_refs() == 1) {
                cell _cont = comment~load_ref();
                comment = _cont.begin_parse();
                current_slice_length = comment.slice_bits() / 8;
                counter = 0;
            }
        }
    }
    return (comment, result);
}

slice make_address(int wc, int addr) inline_ref {
    return begin_cell()
           .store_uint(4, 3).store_int(wc, 8).store_uint(addr, ADDR_SIZE()).end_cell().begin_parse();
}

;; https://github.com/ton-blockchain/ton/blob/ae5c0720143e231c32c3d2034cfe4e533a16d969/crypto/block/block.tlb#L584
int is_elector_address(int wc, int addr) inline_ref {
  return (wc == -1) & (config_param(1).begin_parse().preload_uint(ADDR_SIZE()) == addr);
}

slice elector_address() inline_ref {
    int elector = config_param(1).begin_parse().preload_uint(ADDR_SIZE());
    return make_address(-1, elector);
}

;; https://github.com/ton-blockchain/ton/blob/ae5c0720143e231c32c3d2034cfe4e533a16d969/crypto/block/block.tlb#L721
int max_recommended_punishment_for_validator_misbehaviour(int stake) inline_ref {
    cell cp = config_param(40);
    if (cell_null?(cp)) {
        return 101000000000; ;; 101 TON - https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/lite-client/lite-client.cpp#L3678
    }

    slice cs = cp.begin_parse();

    (int prefix,
     int default_flat_fine, int default_proportional_fine,
     int severity_flat_mult, int severity_proportional_mult,
     int unpunishable_interval,
     int long_interval, int long_flat_mult, int long_proportional_mult) =
        (cs~load_uint(8),
         cs~load_coins(), cs~load_uint(32),
         cs~load_uint(16), cs~load_uint(16),
         cs~load_uint(16),
         cs~load_uint(16), cs~load_uint(16), cs~load_uint(16)
        );

     ;; https://github.com/ton-blockchain/ton/blob/master/lite-client/lite-client.cpp#L3721
     int fine = default_flat_fine;
     int fine_part = default_proportional_fine;

     fine *= severity_flat_mult; fine >>= 8;
     fine_part *= severity_proportional_mult; fine_part >>= 8;

     fine *= long_flat_mult; fine >>= 8;
     fine_part *= long_proportional_mult; fine_part >>= 8;

     return min(stake, fine + muldiv(stake, fine_part, 1 << 32)); ;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L529
}

;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/block/block.tlb#L632
;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L118
int get_validator_config() inline_ref {
    slice cs = config_param(15).begin_parse();
    (int validators_elected_for, int elections_start_before, int elections_end_before, int stake_held_for) = (cs~load_uint(32), cs~load_uint(32), cs~load_uint(32), cs.preload_uint(32));
    return stake_held_for;
}

;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/block/block.tlb#L712
(int, int, cell) get_current_validator_set() inline_ref {
    cell vset = config_param(34); ;; current validator set
    slice cs = vset.begin_parse();
    ;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/block/block.tlb#L579
    ;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/config-code.fc#L49
    throw_unless(9, cs~load_uint(8) == 0x12);  ;; validators_ext#12 only
    int utime_since = cs~load_uint(32); ;; actual start unixtime of current validation round
    int utime_until = cs~load_uint(32); ;; supposed end unixtime of current validation round (utime_until = utime_since + validators_elected_for); unfreeze_at = utime_until + stake_held_for
    return (utime_since, utime_until, vset);
}

;; check the validity of the new_stake message
;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L208
int check_new_stake_msg(slice cs) impure inline_ref {
    var validator_pubkey = cs~load_uint(256);
    var stake_at = cs~load_uint(32);
    var max_factor = cs~load_uint(32);
    var adnl_addr = cs~load_uint(256);
    var signature = cs~load_ref().begin_parse().preload_bits(512);
    cs.end_parse();
    return stake_at; ;; supposed start of next validation round (utime_since)
}

builder pack_nominator(int amount, int pending_deposit_amount) inline_ref {
    return begin_cell().store_coins(amount).store_coins(pending_deposit_amount);
}

(int, int) unpack_nominator(slice ds) inline_ref {
    return (
        ds~load_coins(), ;; amount
        ds~load_coins()  ;; pending_deposit_amount
    );
}

cell pack_config(int validator_address, int validator_reward_share, int max_nominators_count, int min_validator_stake, int min_nominator_stake) inline_ref {
    return begin_cell()
        .store_uint(validator_address, ADDR_SIZE())
        .store_uint(validator_reward_share, 16)
        .store_uint(max_nominators_count, 16)
        .store_coins(min_validator_stake)
        .store_coins(min_nominator_stake)
        .end_cell();
}

(int, int, int, int, int) unpack_config(slice ds) inline_ref {
    return (
        ds~load_uint(ADDR_SIZE()), ;; validator_address
        ds~load_uint(16), ;; validator_reward_share
        ds~load_uint(16), ;; max_nominators_count
        ds~load_coins(), ;; min_validator_stake
        ds~load_coins() ;; min_nominator_stake
    );
}

() save_data(int state, int nominators_count, int stake_amount_sent, int validator_amount, cell config, cell nominators, cell withdraw_requests, int stake_at, int saved_validator_set_hash, int validator_set_changes_count, int validator_set_change_time, int stake_held_for, cell config_proposal_votings) impure inline_ref {
    set_data(begin_cell()
        .store_uint(state, 8)
        .store_uint(nominators_count, 16)
        .store_coins(stake_amount_sent)
        .store_coins(validator_amount)
        .store_ref(config)
        .store_dict(nominators)
        .store_dict(withdraw_requests)
        .store_uint(stake_at, 32)
        .store_uint(saved_validator_set_hash, 256)
        .store_uint(validator_set_changes_count, 8)
        .store_uint(validator_set_change_time, 32)
        .store_uint(stake_held_for, 32)
        .store_dict(config_proposal_votings)
        .end_cell());
}

(int, int, int, int, (int, int, int, int, int), cell, cell, int, int, int, int, int, cell) load_data() inline_ref {
    slice ds = get_data().begin_parse();
    return (
        ds~load_uint(8), ;; state
        ds~load_uint(16), ;; nominators_count
        ds~load_coins(), ;; stake_amount_sent
        ds~load_coins(), ;; validator_amount
        unpack_config(ds~load_ref().begin_parse()), ;; config
        ds~load_dict(), ;; nominators
        ds~load_dict(), ;; withdraw_requests
        ds~load_uint(32), ;; stake_at
        ds~load_uint(256), ;; saved_validator_set_hash
        ds~load_uint(8), ;; validator_set_changes_count
        ds~load_uint(32), ;; validator_set_change_time
        ds~load_uint(32), ;; stake_held_for
        ds~load_dict() ;; config_proposal_votings
    );
}

() send_msg(slice to_address, int amount, cell payload, int flags, int send_mode) impure inline_ref {
    int has_payload = ~ cell_null?(payload);

    builder msg = begin_cell()
        .store_uint(flags, 6)
        .store_slice(to_address)
        .store_coins(amount)
        .store_uint(has_payload ? 1 : 0, 1 + 4 + 4 + 64 + 32 + 1 + 1);

    if (has_payload) {
        msg = msg.store_ref(payload);
    }

    send_raw_message(msg.end_cell(), send_mode);
}

() send_excesses(slice sender_address) impure inline_ref {
    send_msg(sender_address, 0, null(), NON_BOUNCEABLE(), SEND_MODE_REMAINING_AMOUNT() + SEND_MODE_IGNORE_ERRORS()); ;; non-bouneable, remaining inbound message amount, fee deducted from amount, ignore errors
}

(cell, cell, int, int) withdraw_nominator(int address, cell nominators, cell withdraw_requests, int balance, int nominators_count) impure inline_ref {
    (slice nominator, int found) = nominators.udict_get?(ADDR_SIZE(), address);
    throw_unless(60, found);
    (int amount, int pending_deposit_amount) = unpack_nominator(nominator);
    int withdraw_amount = amount + pending_deposit_amount;

    if (withdraw_amount > balance - MIN_TONS_FOR_STORAGE()) {
        return (nominators, withdraw_requests, balance, nominators_count);
    }

    nominators~udict_delete?(ADDR_SIZE(), address);
    withdraw_requests~udict_delete?(ADDR_SIZE(), address);
    nominators_count -= 1;
    balance -= withdraw_amount;

    if (withdraw_amount >= ONE_TON()) {
        send_msg(make_address(0, address), withdraw_amount, null(), NON_BOUNCEABLE(), 0); ;; non-bouneable, fee deducted from amount, revert on errors
    }
    return (nominators, withdraw_requests, balance, nominators_count);
}

(cell, cell, int, int) process_withdraw_requests(cell nominators, cell withdraw_requests, int balance, int nominators_count, int limit) impure inline_ref {
    int count = 0;
    int address = -1;
    int need_break = 0;
    do {
        (address, slice cs, int f) = withdraw_requests.udict_get_next?(ADDR_SIZE(), address);
        if (f) {
            (nominators, withdraw_requests, int new_balance, nominators_count) = withdraw_nominator(address, nominators, withdraw_requests, balance, nominators_count);
            need_break = (new_balance == balance);
            balance = new_balance;
            count += 1;
            if (count >= limit) {
                need_break = -1;
            }
        }
    } until ((~ f) | (need_break));

    return (nominators, withdraw_requests, nominators_count, balance);
}

int calculate_total_nominators_amount(cell nominators) inline_ref {
    int total = 0;
    int address = -1;
    do {
        (address, slice cs, int f) = nominators.udict_get_next?(ADDR_SIZE(), address);
        if (f) {
            (int amount, int pending_deposit_amount) = unpack_nominator(cs);
            total += (amount + pending_deposit_amount);
        }
    } until (~ f);
    return total;
}

cell distribute_share(int reward, cell nominators) inline_ref {
    int total_amount = 0;
    int address = -1;
    do {
        (address, slice cs, int f) = nominators.udict_get_next?(ADDR_SIZE(), address);
        if (f) {
            (int amount, int pending_deposit_amount) = unpack_nominator(cs);
            total_amount += amount;
        }
    } until (~ f);

    cell new_nominators = new_dict();
    address = -1;
    do {
        (address, slice cs, int f) = nominators.udict_get_next?(ADDR_SIZE(), address);
        if (f) {
            (int amount, int pending_deposit_amount) = unpack_nominator(cs);
            if (total_amount > 0) {
                amount += muldiv(reward, amount, total_amount);
                if (amount < 0) {
                    amount = 0;
                }
            }
            amount += pending_deposit_amount;
            new_nominators~udict_set_builder(ADDR_SIZE(), address, pack_nominator(amount, 0));
        }
    } until (~ f);

    return new_nominators;
}

() recv_internal(int msg_value, cell in_msg_full, slice in_msg_body) impure {
    int balance = pair_first(get_balance());

    slice cs = in_msg_full.begin_parse();
    int flags = cs~load_uint(4);

    slice sender_address = cs~load_msg_addr();
    (int sender_wc, int sender_addr) = parse_std_addr(sender_address);

    if (flags & 1) { ;; bounced messages
        if (in_msg_body.slice_bits() >= 64) {
            in_msg_body~skip_bits(32); ;; skip 0xFFFFFFFF bounced prefix
            int op = in_msg_body~load_uint(32);
            if ((op == op::new_stake()) & (is_elector_address(sender_wc, sender_addr))) {
                ;; `new_stake` from nominator-pool should always be handled without throws by elector
                ;; because nominator-pool do `check_new_stake_msg` and `msg_value` checks before sending `new_stake`.
                ;; If the stake is not accepted elector will send `new_stake_error` response message.
                ;; Nevertheless we do process theoretically possible bounced `new_stake`.

                (int state, int nominators_count, int stake_amount_sent, int validator_amount, (int validator_address, int validator_reward_share, int max_nominators_count, int min_validator_stake, int min_nominator_stake), cell nominators, cell withdraw_requests, int stake_at, int saved_validator_set_hash, int validator_set_changes_count, int validator_set_change_time, int stake_held_for, cell config_proposal_votings) = load_data();
                if (state == 1) {
                    state = 0;
                }
                save_data(
                    state,
                    nominators_count,
                    stake_amount_sent,
                    validator_amount,
                    pack_config(validator_address, validator_reward_share, max_nominators_count, min_validator_stake, min_nominator_stake),
                    nominators,
                    withdraw_requests,
                    stake_at,
                    saved_validator_set_hash,
                    validator_set_changes_count,
                    validator_set_change_time,
                    stake_held_for,
                    config_proposal_votings
                );
            }
        }
        return (); ;; ignore other bounces messages
    }

    int op = in_msg_body~load_uint(32);

   (int state, int nominators_count, int stake_amount_sent, int validator_amount, (int validator_address, int validator_reward_share, int max_nominators_count, int min_validator_stake, int min_nominator_stake), cell nominators, cell withdraw_requests, int stake_at, int saved_validator_set_hash, int validator_set_changes_count, int validator_set_change_time, int stake_held_for, cell config_proposal_votings) = load_data();

    if (op == 0) {
        ;; We use simple text comments for nominator operations so nominators can do it from any wallet app.
        ;; In other cases, they will need to put a stake on a browser extension, or use scripts, which can be inconvenient.

        ;; Throw on any unexpected request so that the stake is bounced back to the nominator in case of a typo.

        int action = in_msg_body~load_uint(8);
        int is_vote = (action == 121) | (action == 110); ;; "y" or "n"
        throw_unless(64, (action == 100) | (action == 119) | is_vote); ;; "d" or "w" or "y" or "n"

        if (~ is_vote) {
            in_msg_body.end_parse();
            throw_unless(61, sender_wc == 0); ;; nominators only in basechain
            throw_unless(62, sender_addr != validator_address);
        }

        if (action == 100) { ;; "d" - deposit nominator (any time, will take effect in the next round)
            (slice nominator, int found) = nominators.udict_get?(ADDR_SIZE(), sender_addr);

            if (~ found) {
                nominators_count += 1;
            }
            throw_unless(65, nominators_count <= max_nominators_count);

            msg_value -= DEPOSIT_PROCESSING_FEE();
            throw_unless(66, msg_value > 0);

            (int amount, int pending_deposit_amount) = found ? unpack_nominator(nominator) : (0, 0);
            if (state == 0) {
                amount += msg_value;
            } else {
                pending_deposit_amount += msg_value;
            }
            throw_unless(67, amount + pending_deposit_amount >= min_nominator_stake);
            throw_unless(68, cell_depth(nominators) < max(5, binary_log_ceil(nominators_count) * 2) ); ;; prevent dict depth ddos
            nominators~udict_set_builder(ADDR_SIZE(), sender_addr, pack_nominator(amount, pending_deposit_amount));
        }

        if (action == 119) { ;; "w" - withdraw request (any time)
            if (state == 0) {
                (nominators, withdraw_requests, int new_balance, nominators_count) = withdraw_nominator(sender_addr, nominators, withdraw_requests, balance, nominators_count);
                if (new_balance - msg_value >= MIN_TONS_FOR_STORAGE()) {
                    send_excesses(sender_address);
                }
            } else {
                (slice nominator, int found) = nominators.udict_get?(ADDR_SIZE(), sender_addr);
                throw_unless(69, found);
                withdraw_requests~udict_set_builder(ADDR_SIZE(), sender_addr, begin_cell());
                send_excesses(sender_address);
            }
        }

        if (is_vote) {
            int authorized = (sender_wc == -1) & (sender_addr == validator_address);

            if (~ authorized) {
                throw_unless(121, sender_wc == 0);
                (slice nominator, authorized) = nominators.udict_get?(ADDR_SIZE(), sender_addr);
                throw_unless(122, authorized);
                (int amount, int pending_deposit_amount) = unpack_nominator(nominator);
                throw_unless(123, amount > 0);
            }

            int proposal_hash = in_msg_body~load_text_hex_number(32);
            in_msg_body.end_parse();
            int support = action == 121;

            (slice votes_slice, int found) = config_proposal_votings.udict_get?(256, proposal_hash);

            if (~ found) {
                ;; require higher fee to prevent dictionary spam
                int fee = ONE_TON();
                int power = cell_depth(config_proposal_votings);
                repeat (power) {
                    fee = muldiv(fee, 15, 10);
               }
               throw_unless(123, msg_value >= fee);
            }

            (cell votes_dict, int votes_create_time) = found ? (votes_slice~load_dict(), votes_slice~load_uint(32)) : (new_dict(), now());

            (_, int vote_found) = votes_dict.udict_get?(256, sender_addr);
            throw_if(124, vote_found);
            votes_dict~udict_set_builder(256, sender_addr, begin_cell().store_int(support, 1).store_uint(now(), 32));

            builder new_votes = begin_cell().store_dict(votes_dict).store_uint(votes_create_time, 32);
            config_proposal_votings~udict_set_builder(256, proposal_hash, new_votes);

            if (found) {
                send_excesses(sender_address);
            }
        }

    } else {

        int query_id = in_msg_body~load_uint(64);

        if (is_elector_address(sender_wc, sender_addr)) { ;; response from elector

            accept_message();

            if (op == op::recover_stake_ok()) {
                state = 0;

                int reward = msg_value - stake_amount_sent;
                int nominators_reward = 0;

                if (reward <= 0) {
                    validator_amount += reward;
                    if (validator_amount < 0) {
                        ;; even this should never happen
                        nominators_reward = validator_amount;
                        validator_amount = 0;
                    }
                } else {
                    int validator_reward = (reward * validator_reward_share) / 10000;
                    if (validator_reward > reward) { ;; Theoretical invalid case if validator_reward_share > 10000
                        validator_reward = reward;
                    }
                    validator_amount += validator_reward;
                    nominators_reward = reward - validator_reward;
                }

                nominators = distribute_share(nominators_reward, nominators); ;; call even if there was no reward to process deposit requests
                stake_amount_sent = 0;
            }

            if (state == 1) {
                if (op == op::new_stake_error()) { ;; error when new_stake; stake returned
                    state = 0;
                }

                if (op == op::new_stake_ok()) {
                    state = 2;
                }
            }

            ;; else just accept coins from elector

        } else {

            ;; throw on any unexpected request so that the coins is bounced back to the sender in case of a typo
            throw_unless(70, ((op >= 1) & (op <= 7)) | (op == op::recover_stake()) | (op == op::new_stake()));

            if (op == 1) {
                ;; just accept coins
            }

            if (op == 2) { ;; process withdraw requests (at any time while the balance is enough)
                int limit = in_msg_body~load_uint(8);

                (nominators, withdraw_requests, nominators_count, int new_balance) = process_withdraw_requests(nominators, withdraw_requests, balance, nominators_count, limit);

                if (new_balance - msg_value >= MIN_TONS_FOR_STORAGE()) {
                    send_excesses(sender_address);
                }
            }

            if (op == 3) { ;; emergency process withdraw request  (at any time if the balance is enough)
                int request_address = in_msg_body~load_uint(ADDR_SIZE());
                (slice withdraw_request, int found) = withdraw_requests.udict_get?(ADDR_SIZE(), request_address);
                throw_unless(71, found);
                (nominators, withdraw_requests, int new_balance, nominators_count) = withdraw_nominator(request_address, nominators, withdraw_requests, balance, nominators_count);
                if (new_balance - msg_value >= MIN_TONS_FOR_STORAGE()) {
                    send_excesses(sender_address);
                }
            }

            if (op == 6) { ;; update current valudator set hash (anyone can invoke)
                throw_unless(113, validator_set_changes_count < 3);
                (int utime_since, int utime_until, cell vset) = get_current_validator_set();
                int current_hash = cell_hash(vset);
                if (saved_validator_set_hash != current_hash) {
                    saved_validator_set_hash = current_hash;
                    validator_set_changes_count += 1;
                    validator_set_change_time = now();
                }
                send_excesses(sender_address);
            }

            if (op == 7) { ;; clean up outdating votings
                int t = now();
                int proposal_hash = -1;
                do {
                    (proposal_hash, slice votes_slice, int found) = config_proposal_votings.udict_get_next?(256, proposal_hash);
                    if (found) {
                        (cell votes_dict, int votes_create_time) = (votes_slice~load_dict(), votes_slice~load_uint(32));
                        if (t - votes_create_time > VOTES_LIFETIME()) {
                            config_proposal_votings~udict_delete?(256, proposal_hash);
                        }
                    }
                } until (~ found);
                send_excesses(sender_address);
            }

            if (op == op::recover_stake()) { ;; send recover_stake to elector (anyone can send)

                ;; We need to take all credits from the elector at once,
                ;; because if we do not take all at once, then it will be processed as a fine by pool.
                ;; In the elector, credits (`credit_to`) are accrued in three places:
                ;; 1) return of surplus stake in elections (`try_elect`)
                ;; 2) reward for complaint when punish (`punish`) - before unfreezing
                ;; 3) unfreeze round (`unfreeze_without_bonuses`/`unfreeze_with_bonuses`)
                ;; We need to be guaranteed to wait for unfreezing round and only then send `recover_stake`.
                ;; So we are waiting for the change of 3 validator sets.

                ;; ADDITIONAL NOTE:
                ;; In a special case (if the network was down), the config theoretically can refuse the elector to save a new round after election - https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/config-code.fc#L494
                ;; and the elector will start a new election - https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L364
                ;; in this case, our pool will have to skip the round, but it will be able to recover stake later

                throw_unless(111, validator_set_changes_count >= 2);
                throw_unless(112, (validator_set_changes_count > 2) | (now() - validator_set_change_time > stake_held_for + 60));
                ;; https://github.com/ton-blockchain/ton/blob/b38d227a469666d83ac535ad2eea80cb49d911b8/crypto/smartcont/elector-code.fc#L887

                cell payload = begin_cell().store_uint(op::recover_stake(), 32).store_uint(query_id, 64).end_cell();
                send_msg(elector_address(), 0, payload, BOUNCEABLE(), SEND_MODE_REMAINING_AMOUNT()); ;; bounceable,  carry all the remaining value of the inbound message, fee deducted from amount, revert on errors
            }

            ;; message from validator

            if (op == 4) { ;; deposit validator (any time)
                throw_unless(73, (sender_wc == -1) & (sender_addr == validator_address));
                msg_value -= DEPOSIT_PROCESSING_FEE();
                throw_unless(74, msg_value > 0);
                validator_amount += msg_value;
            }

            if (op == 5) { ;; withdraw validator (after recover_stake and before new_stake)
                throw_unless(74, state == 0); ;; no withdraw request because validator software can wait right time
                throw_unless(75, (sender_wc == -1) & (sender_addr == validator_address));
                int request_amount = in_msg_body~load_coins();
                throw_unless(78, request_amount > 0);

                int total_nominators_amount = calculate_total_nominators_amount(nominators);
                ;; the validator can withdraw everything that does not belong to the nominators
                throw_unless(76, request_amount <= balance - MIN_TONS_FOR_STORAGE() - total_nominators_amount);
                validator_amount -= request_amount;
                if (validator_amount < 0) {
                    validator_amount = 0;
                }
                send_msg(make_address(-1, validator_address), request_amount, null(), NON_BOUNCEABLE(), 0); ;; non-bouneable, fee deducted from amount, revert on errors
                int new_balance = balance - request_amount;
                if (new_balance - msg_value >= MIN_TONS_FOR_STORAGE()) {
                    send_excesses(sender_address);
                }
            }

            if (op == op::new_stake()) {
                throw_unless(78, (sender_wc == -1) & (sender_addr == validator_address));

                throw_unless(79, state == 0);

                throw_unless(80, query_id); ;; query_id must be greater then 0 to receive confirmation message from elector

                throw_unless(86, msg_value >= ONE_TON()); ;; must be greater then new_stake sending to elector fee

                int value = in_msg_body~load_coins();

                slice msg = in_msg_body;

                stake_at = check_new_stake_msg(in_msg_body);

                stake_amount_sent = value - ONE_TON();

                throw_unless(81, value >= MIN_STAKE_TO_SEND());

                throw_unless(82, value <= balance - MIN_TONS_FOR_STORAGE());

                throw_unless(83, validator_amount >= min_validator_stake);

                throw_unless(84, validator_amount >= max_recommended_punishment_for_validator_misbehaviour(stake_amount_sent));

                throw_unless(85, cell_null?(withdraw_requests)); ;; no withdraw requests

                state = 1;
                (int utime_since, int utime_until, cell vset) = get_current_validator_set();
                saved_validator_set_hash = cell_hash(vset); ;; current validator set, we will be in next validator set
                validator_set_changes_count = 0;
                validator_set_change_time = utime_since;
                stake_held_for = get_validator_config(); ;; save `stake_held_for` in case the config changes in the process

                send_msg(elector_address(), value, begin_cell().store_uint(op, 32).store_uint(query_id, 64).store_slice(msg).end_cell(), BOUNCEABLE(), SEND_MODE_PAY_FEE_SEPARATELY()); ;; pay fee separately, rever on errors
            }
        }
    }

    save_data(
        state,
        nominators_count,
        stake_amount_sent,
        validator_amount,
        pack_config(validator_address, validator_reward_share, max_nominators_count, min_validator_stake, min_nominator_stake),
        nominators,
        withdraw_requests,
        stake_at,
        saved_validator_set_hash,
        validator_set_changes_count,
        validator_set_change_time,
        stake_held_for,
        config_proposal_votings
    );
}

;; Get methods

_ get_pool_data() method_id {
    return load_data();
}

int has_withdraw_requests() method_id {
    (int state, int nominators_count, int stake_amount_sent, int validator_amount, (int validator_address, int validator_reward_share, int max_nominators_count, int min_validator_stake, int min_nominator_stake), cell nominators, cell withdraw_requests, int stake_at, int saved_validator_set_hash, int validator_set_changes_count, int validator_set_change_time, int stake_held_for, cell config_proposal_votings) = load_data();
    return ~ cell_null?(withdraw_requests);
}

(int, int, int) get_nominator_data(int nominator_address) method_id {
    (int state, int nominators_count, int stake_amount_sent, int validator_amount, (int validator_address, int validator_reward_share, int max_nominators_count, int min_validator_stake, int min_nominator_stake), cell nominators, cell withdraw_requests, int stake_at, int saved_validator_set_hash, int validator_set_changes_count, int validator_set_change_time, int stake_held_for, cell config_proposal_votings) = load_data();

    (slice nominator, int found) = nominators.udict_get?(ADDR_SIZE(), nominator_address);
    throw_unless(86, found);
    (int amount, int pending_deposit_amount) = unpack_nominator(nominator);
    (slice withdraw_request, int withdraw_found) = withdraw_requests.udict_get?(ADDR_SIZE(), nominator_address);

    return (amount, pending_deposit_amount, withdraw_found);
}

int get_max_punishment(int stake) method_id {
    return max_recommended_punishment_for_validator_misbehaviour(stake);
}

tuple list_nominators() method_id {
    (int state, int nominators_count, int stake_amount_sent, int validator_amount, (int validator_address, int validator_reward_share, int max_nominators_count, int min_validator_stake, int min_nominator_stake), cell nominators, cell withdraw_requests, int stake_at, int saved_validator_set_hash, int validator_set_changes_count, int validator_set_change_time, int stake_held_for, cell config_proposal_votings) = load_data();
    var list = null();
    int address = -1;
    do {
        (address, slice nominator, int found) = nominators.udict_get_next?(ADDR_SIZE(), address);
        if (found) {
            (int amount, int pending_deposit_amount) = unpack_nominator(nominator);
            (_, int withdraw_requested) = withdraw_requests.udict_get?(ADDR_SIZE(), address);
            list = cons(tuple4(address, amount, pending_deposit_amount, withdraw_requested), list);
        }
    } until (~ found);
    return list;
}

tuple list_votes() method_id {
    (int state, int nominators_count, int stake_amount_sent, int validator_amount, (int validator_address, int validator_reward_share, int max_nominators_count, int min_validator_stake, int min_nominator_stake), cell nominators, cell withdraw_requests, int stake_at, int saved_validator_set_hash, int validator_set_changes_count, int validator_set_change_time, int stake_held_for, cell config_proposal_votings) = load_data();
    var list = null();
    int proposal_hash = -1;
    do {
        (proposal_hash, slice votes_slice, int found) = config_proposal_votings.udict_get_next?(256, proposal_hash);
        if (found) {
            (cell votes_dict, int votes_create_time) = (votes_slice~load_dict(), votes_slice~load_uint(32));
            list = cons(pair(proposal_hash, votes_create_time), list);
        }
    } until (~ found);
    return list;
}

tuple list_voters(int proposal_hash) method_id {
    (int state, int nominators_count, int stake_amount_sent, int validator_amount, (int validator_address, int validator_reward_share, int max_nominators_count, int min_validator_stake, int min_nominator_stake), cell nominators, cell withdraw_requests, int stake_at, int saved_validator_set_hash, int validator_set_changes_count, int validator_set_change_time, int stake_held_for, cell config_proposal_votings) = load_data();
    var list = null();
    (slice votes_slice, int found) = config_proposal_votings.udict_get?(256, proposal_hash);
    throw_unless(133, found);
    cell votes_dict = votes_slice~load_dict();

    int address = -1;
    do {
        (address, slice cs, int found) = votes_dict.udict_get_next?(ADDR_SIZE(), address);
        if (found) {
            (int support, int vote_time) = (cs~load_int(1), cs~load_uint(32));
            list = cons(triple(address, support, vote_time), list);
        }
    } until (~ found);
    return list;
}