ICO/Payment contact

Question

Anyone is working on some ICO/Payment contacts?
What I would like to learn are following functionalities within the contract:

1. Payment, where the fee is split into 3 accounts.

   a) So user sends a fee in some token (defined in separate contract), there is a check if the balance is positibe, and then fee is divided and send to three accounts.

2. A user sends EOS (SYS) token and receives application token with a given exchange rate

3. The transaction can be executed only within certain time frames. If not then it is rejected.

Any github sample to share?

Answer 1

Look at this example:

https://gist.github.com/MikkySnow/feac6fd5a9d49da207b9bd59d3c672c4

Hope it will help you

#include <eosiolib/eosio.hpp>
#include <eosiolib/currency.hpp>

using namespace eosio;

class hello : public eosio::contract {
  public:
      using contract::contract;

      hello(account_name self) : contract(self) {}

      /// @abi table 
      struct account {
        account_name owner;
        uint64_t balance;

        uint64_t primary_key() const { return owner; };
      };

      typedef eosio::multi_index<N(account), account> accs; 

      /// @abi action 
      void addbalance(account_name owner, uint64_t amount) {
         accs accounts(_self, owner);
         auto existing = accounts.find(owner);

         if (existing == accounts.end())
         {
            /* Add new account */
            accounts.emplace(_self, [&](auto& a) {
                a.owner = owner;
                a.balance = amount;
            });
         } else {
            /* Update existing account */
            const auto& st = *existing;
            accounts.modify(st, 0, [&](auto& a) {
                a.balance += amount;
            });
         }
      }

      void on(const currency::transfer& t) {
        if (t.to == _self) {
            addbalance(t.from, t.quantity.amount);
        }
      }

      void use(account_name contract, account_name act) {
        if (act == N(transfer)) {
            on(unpack_action_data<currency::transfer>());
            return;
        }

        auto& thiscontract = *this;
        switch( act ) {
            EOSIO_API( hello, (addbalance));
        };
      }
};

extern "C" {
   [[noreturn]] void apply( uint64_t receiver, uint64_t code, uint64_t action ) {
      hello  h( receiver );
      h.use( code, action );
      eosio_exit(0);
   }
}