1 files changed, 30 insertions, 0 deletions
diff --git a/contracts/Lottery.sol b/contracts/Lottery.sol
new file mode 100644
index 0000000..26ec7af
--- /dev/null
+++ b/contracts/Lottery.sol
@@ -0,0 +1,30 @@
+pragma solidity ^0.5.2;
+
+import "openzeppelin-solidity/contracts/ownership/Ownable.sol";
+
+contract Lottery is Ownable {
+    mapping (uint256 => uint256) public numberOfTime;
+    uint256[] public revealedTimes;
+    uint256 public revealedTimesCount = 0;
+    uint256 public lastRevealedTime;
+
+    event NumberRevealed(uint256 indexed timestamp, uint256 number, uint256 rawValue);
+
+    function reveal(uint256 timestamp) public onlyOwner {
+        // check if timestamp is in the future
+        // or if number of timestamp is already revealed
+        if (timestamp > now || numberOfTime[timestamp] != 0) {
+            revert();
+        }
+
+        uint256 rawValue = rand;
+        uint256 number = rawValue % 1000;
+
+        numberOfTime[timestamp] = number;
+        revealedTimes.push(timestamp);
+        revealedTimesCount++;
+        lastRevealedTime = timestamp;
+
+        emit NumberRevealed(timestamp, number, rawValue);
+    }
+}