// SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;

import "@chainlink/contracts/src/v0.8/ChainlinkClient.sol";
import "@chainlink/contracts/src/v0.8/ConfirmedOwner.sol";
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/utils/Strings.sol";

contract PredictGame is ChainlinkClient, ConfirmedOwner {
    using Chainlink for Chainlink.Request;
		ERC20 private ERCinstance;    // ERC20 토큰을 다루기 위한 인터페이스
    address public tokenAdress; // This is the token address
    address payable public host; // This is the client
    // 토큰을 보냈을때 로그
    event Transfer(address indexed _from, address indexed _to, uint256 _value); 
    event Approval(address indexed _owner, address indexed _spender, uint256 _value); 
    // getDaysEthUsdPrices 를 실행할때 request 를 보내는 url 의 로그를 찍는 이벤트
    event APIurl(string api); 

    //variables used for oracle
    address private oracle; // 오라클 주소
    bytes32 private jobId; // jobid
    uint256 private fee; // link fee
    
    event RequestVolume(bytes32 indexed requestId, uint256 volume);
    // 20230607 -> 0 (해당 날짜를 모두 ethUsdPrices 에 저장하면 6이 저장된다.)
		mapping(uint256 => uint8) private datetemp; 
		// 20230627 -> [가격1, 가격2, 가격3, 가격4]. (시작날자 -> 가격 4개 매핑)
    mapping(uint256 => uint256[4]) private ethUsdPrices; 
		constructor() ConfirmedOwner(msg.sender){
		        // 배포된 tokenAddress 를 입력
		        tokenAdress = 0x7caEd854Dac539EE7E28a3E42Cdc68F32665F7A6; 
		        ERCinstance = ERC20 (tokenAdress); // ERC20 인터페이스로 해당 token address 를 감싼다.
		        host = payable(msg.sender);
		        //default values
		        setChainlinkToken(0x779877A7B0D9E8603169DdbD7836e478b4624789);
		        setChainlinkOracle(0x6090149792dAAeE9D1D568c9f9a6F6B46AA29eFD);
		        jobId = "ca98366cc7314957b8c012c72f05aeeb"; 
		        fee = (1 * LINK_DIVISIBILITY) / 10; // 0,1 * 10**18 (Varies by network and job)
		}

		function getDaysEthUsdPrices(uint256 _timestamp) internal returns(bytes32 requestId) { 
	        Chainlink.Request memory req = buildChainlinkRequest(
	            jobId,
	            address(this),
	            this.fulfill.selector
	        );
	        req.add(
	            "get",
	            string(abi.encodePacked("https://min-api.cryptocompare.com/data/pricemultifull?fsyms=ETH&tsyms=USD&ts=", Strings.toString(_timestamp)))
	            
	        );
	        // requst를 보낸 URL 을 확인하는 로그를 찍는다.
	        emit APIurl(string(abi.encodePacked("https://min-api.cryptocompare.com/data/pricemultifull?fsyms=ETH&tsyms=USD&ts=", Strings.toString(_timestamp))));
	
	        // Set the path to find the desired data in the API response
	        req.add("path", "RAW,ETH,USD,VOLUME24HOUR");
	
	        // Multiply the result by 1000000000000000000 to remove decimals
	        int256 timesAmount = 10 ** 18;
	        req.addInt("times", timesAmount);
	
	        // Sends the request
	        return sendChainlinkRequest(req, fee);
		}

		function fulfill(bytes32 _requestId, uint256 _price) public recordChainlinkFulfillment(_requestId) {
			emit RequestVolume(_requestId, _price);
			
			// datetemp[startdate] 으로 startdate 해당하는 가격을 어디까지 불러왔는지 알 수 있다.
			//ethUsdPrices[20230627] 이 [2131511,23155,0,0] 이면 datetemp[20230627] 의 값은 2 
					// 예 datetemp[20230627] 의 값이 2 이면 20230627 에 시작하는 날짜의 가격
			if(datetemp[getYearMonthDay(block.timestamp)] == 0){ 
				ethUsdPrices[getYearMonthDay(block.timestamp)][datetemp[getYearMonthDay(block.timestamp)]++] = _price; 
			} 
			// 전에 불러왔던 가격이 현재 받은 가격과 다르면 ethUsdPrices 에 저장. 
			// 두개의 가격이 같으면 같은 response 를 받은 것이다.
			else if(ethUsdPrices[getYearMonthDay(block.timestamp)][datetemp[getYearMonthDay(block.timestamp) - 1]] != _price){
				ethUsdPrices[getYearMonthDay(block.timestamp)][datetemp[getYearMonthDay(block.timestamp)]++] = _price; 
			}
        
		}

		function getYearMonthDay(uint256 timestamp) internal pure returns (uint256) {
			// 31556926 is the number of seconds in a year
			uint256 year = (timestamp / 31556926) + 1970; 
			// 2629743 is the number of seconds in a month
			uint256 month = (timestamp / 2629743) % 12; 
			uint256 day = (timestamp / 86400) % 31; // 86400 is the number of seconds in a day

			// Combine the components into a single uint256 value
			uint256 date = (year * 10000) + (month * 100) + day;
			return date;
    }