{-
Forward fee calculation supporting different workchains
-}

;; See crypto/block/transaction.cpp:L1499
int msg_fwd_fee(slice destination, cell message_body, cell init_state, int max_viewed_cells) inline {
    (int wc, _) = parse_std_addr(destination);
    throw_unless(107, (workchain == -1) | (workchain == 0) );
    int config_index = 25 + workchain;
    slice cfg = config_param(config_index).begin_parse().skip_bits(8);
    int lump_price = cfg~load_uint(64);
    int bit_price = cfg~load_uint(64);
    int cell_price = cfg~load_uint(64);
    (int cells, int bits, _) = compute_data_size(message_body, max_viewed_cells);
    cells -= 1;
    bits -= message_body.slice_bits();

    (int is_cells, int is_bits, _) = compute_data_size(init_state, max_viewed_cells);
    is_cells -= 1;
    is_bits -= init_state.slice_bits();
    return lump_price + (((bits + is_bits) * bit_price + (cells + is_cells) * cell_price + 65535) >> 16 );
}