knight haoyangmao

gistfile1.txt

#include <eosiolib/currency.hpp>
#include <eosiolib/transaction.hpp>
#include <math.h>

#include <eosiolib/asset.hpp>
#include <eosiolib/eosio.hpp>
#include <eosiolib/types.hpp>
#include <string>


#pragma once

// Linear Congruential Generator                                                                                                                          
class random_gen {
public:
    const uint32_t a = 1103515245;
    const uint32_t c = 12345;

    uint64_t seed = 0;

    random_gen(account_name player) {
        if (seed == 0) {
            seed = tapos_block_prefix() + player;
        }
    }

    uint32_t range(uint32_t to) {
        seed = (a * seed + c) % 0x7fffffff;
        return (uint32_t)(seed % to);
    }
};

using eosio::permission_level;
using eosio::action;

class haoyangmao: public eosio::contract
{
public:
    haoyangmao(account_name self) 
      : contract(self) 
    {
    }

    void trypetgacha() {
        require_auth(_self);
        
        random_gen random = random_gen(_self);

        eosio::print(random.seed, '\n');
	
        
        const uint32_t sum = 28960;
        
        int pos = random.range(sum);
		eosio::print(pos);

        if (pos >= 28800 && pos < 28960) {
            eosio::print("got it");
          action(
              permission_level{_self, N(active)},
              N(eosknightsio), N(petgacha),
              std::make_tuple(_self, (uint16_t)2, (uint8_t)1))
              .send();
        } else {
            eosio_assert(false, std::to_string(pos).c_str());
        }
    }
};

EOSIO_ABI(haoyangmao, (trypetgacha))