Update XDCValidator.sol

contracts/validator/contract/XDCValidator.sol

@@ -1,9 +1,7 @@
-
 pragma solidity ^0.4.21;
 
 import "./libs/SafeMath.sol";
 
-
 contract XDCValidator {
     using SafeMath for uint256;
 
@@ -49,20 +47,22 @@ contract XDCValidator {
     uint256 public candidateWithdrawDelay;
     uint256 public voterWithdrawDelay;
 
-    modifier onlyValidCandidateCap {
+    modifier onlyValidCandidateCap() {
         // anyone can deposit X XDC to become a candidate
         require(msg.value >= minCandidateCap);
         _;
     }
 
-    modifier onlyValidVoterCap {
+    modifier onlyValidVoterCap() {
-
         require(msg.value >= minVoterCap);
         _;
     }
 
-    modifier onlyKYCWhitelisted {
+    modifier onlyKYCWhitelisted() {
-       require(KYCString[msg.sender].length!=0 || ownerToCandidate[msg.sender].length>0);
+        require(
+            KYCString[msg.sender].length != 0 ||
+                ownerToCandidate[msg.sender].length > 0
+        );
         _;
     }
 
@@ -89,7 +89,10 @@ contract XDCValidator {
     modifier onlyValidVote(address _candidate, uint256 _cap) {
         require(validatorsState[_candidate].voters[msg.sender] >= _cap);
         if (validatorsState[_candidate].owner == msg.sender) {
-            require(validatorsState[_candidate].voters[msg.sender].sub(_cap) >= minCandidateCap);
+            require(
+                validatorsState[_candidate].voters[msg.sender].sub(_cap) >=
+                    minCandidateCap
+            );
         }
         _;
     }
@@ -98,7 +101,9 @@ contract XDCValidator {
         require(_blockNumber > 0);
         require(block.number >= _blockNumber);
         require(withdrawsState[msg.sender].caps[_blockNumber] > 0);
-        require(withdrawsState[msg.sender].blockNumbers[_index] == _blockNumber);
+        require(
+            withdrawsState[msg.sender].blockNumbers[_index] == _blockNumber
+        );
         _;
     }
 
@@ -129,11 +134,12 @@ contract XDCValidator {
             });
             voters[_candidates[i]].push(_firstOwner);
             ownerToCandidate[_firstOwner].push(_candidates[i]);
-            validatorsState[_candidates[i]].voters[_firstOwner] = minCandidateCap;
+            validatorsState[_candidates[i]].voters[
+                _firstOwner
+            ] = minCandidateCap;
         }
     }
 
-
     // uploadKYC : anyone can upload a KYC; its not equivalent to becoming an owner.
     function uploadKYC(string kychash) external {
         KYCString[msg.sender].push(kychash);
@@ -141,7 +147,15 @@ contract XDCValidator {
     }
 
     // propose : any non-candidate who has uploaded its KYC can become an owner by proposing a candidate.
-    function propose(address _candidate) external payable onlyValidCandidateCap onlyKYCWhitelisted onlyNotCandidate(_candidate) {
+    function propose(
+        address _candidate
+    )
+        external
+        payable
+        onlyValidCandidateCap
+        onlyKYCWhitelisted
+        onlyNotCandidate(_candidate)
+    {
         uint256 cap = validatorsState[_candidate].cap.add(msg.value);
         candidates.push(_candidate);
         validatorsState[_candidate] = ValidatorState({
@@ -149,7 +163,9 @@ contract XDCValidator {
             isCandidate: true,
             cap: cap
         });
-        validatorsState[_candidate].voters[msg.sender] = validatorsState[_candidate].voters[msg.sender].add(msg.value);
+        validatorsState[_candidate].voters[msg.sender] = validatorsState[
+            _candidate
+        ].voters[msg.sender].add(msg.value);
         candidateCount = candidateCount.add(1);
         if (ownerToCandidate[msg.sender].length == 0) {
             owners.push(msg.sender);
@@ -160,12 +176,18 @@ contract XDCValidator {
         emit Propose(msg.sender, _candidate, msg.value);
     }
 
-    function vote(address _candidate) external payable onlyValidVoterCap onlyValidCandidate(_candidate) {
+    function vote(
-        validatorsState[_candidate].cap = validatorsState[_candidate].cap.add(msg.value);
+        address _candidate
+    ) external payable onlyValidVoterCap onlyValidCandidate(_candidate) {
+        validatorsState[_candidate].cap = validatorsState[_candidate].cap.add(
+            msg.value
+        );
         if (validatorsState[_candidate].voters[msg.sender] == 0) {
             voters[_candidate].push(msg.sender);
         }
-        validatorsState[_candidate].voters[msg.sender] = validatorsState[_candidate].voters[msg.sender].add(msg.value);
+        validatorsState[_candidate].voters[msg.sender] = validatorsState[
+            _candidate
+        ].voters[msg.sender].add(msg.value);
         emit Vote(msg.sender, _candidate, msg.value);
     }
 
@@ -177,11 +199,16 @@ contract XDCValidator {
         return validatorsState[_candidate].cap;
     }
 
-    function getCandidateOwner(address _candidate) public view returns(address) {
+    function getCandidateOwner(
+        address _candidate
+    ) public view returns (address) {
         return validatorsState[_candidate].owner;
     }
 
-    function getVoterCap(address _candidate, address _voter) public view returns(uint256) {
+    function getVoterCap(
+        address _candidate,
+        address _voter
+    ) public view returns (uint256) {
         return validatorsState[_candidate].voters[_voter];
     }
 
@@ -197,65 +224,105 @@ contract XDCValidator {
         return withdrawsState[msg.sender].blockNumbers;
     }
 
-    function getWithdrawCap(uint256 _blockNumber) public view returns(uint256) {
+    function getWithdrawCap(
+        uint256 _blockNumber
+    ) public view returns (uint256) {
         return withdrawsState[msg.sender].caps[_blockNumber];
     }
 
-    function unvote(address _candidate, uint256 _cap) public onlyValidVote(_candidate, _cap) {
+    function unvote(
-        validatorsState[_candidate].cap = validatorsState[_candidate].cap.sub(_cap);
+        address _candidate,
-        validatorsState[_candidate].voters[msg.sender] = validatorsState[_candidate].voters[msg.sender].sub(_cap);
+        uint256 _cap
+    ) public onlyValidVote(_candidate, _cap) {
+        validatorsState[_candidate].cap = validatorsState[_candidate].cap.sub(
+            _cap
+        );
+        validatorsState[_candidate].voters[msg.sender] = validatorsState[
+            _candidate
+        ].voters[msg.sender].sub(_cap);
 
         // refund after delay X blocks
         uint256 withdrawBlockNumber = voterWithdrawDelay.add(block.number);
-        withdrawsState[msg.sender].caps[withdrawBlockNumber] = withdrawsState[msg.sender].caps[withdrawBlockNumber].add(_cap);
+        withdrawsState[msg.sender].caps[withdrawBlockNumber] = withdrawsState[
+            msg.sender
+        ].caps[withdrawBlockNumber].add(_cap);
         withdrawsState[msg.sender].blockNumbers.push(withdrawBlockNumber);
 
         emit Unvote(msg.sender, _candidate, _cap);
     }
 
-    function resign(address _candidate) public onlyOwner(_candidate) onlyCandidate(_candidate) {
+    function resign(
+        address _candidate
+    ) public onlyOwner(_candidate) onlyCandidate(_candidate) {
         validatorsState[_candidate].isCandidate = false;
         candidateCount = candidateCount.sub(1);
         for (uint256 i = 0; i < candidates.length; i++) {
             if (candidates[i] == _candidate) {
+                address[] memory cacheArray = ownerToCandidate[msg.sender];
+                uint256 cacheArrayLength = cacheArray.length;
+                for (uint256 j = 0; j < cacheArrayLength; j++) {
+                    if (cacheArray[j] == _candidate) {
+                        delete cacheArray[j];
+                    }
+                }
+                ownerToCandidate[msg.sender] = removeZeroAddresses(cacheArray);
+                if (ownerToCandidate[msg.sender].length == 0) {
+                    ownerCount--;
+                }
                 delete candidates[i];
                 break;
             }
         }
+        candidates = removeZeroAddresses(candidates);
         uint256 cap = validatorsState[_candidate].voters[msg.sender];
-        validatorsState[_candidate].cap = validatorsState[_candidate].cap.sub(cap);
+        validatorsState[_candidate].cap = validatorsState[_candidate].cap.sub(
+            cap
+        );
         validatorsState[_candidate].voters[msg.sender] = 0;
         // refunding after resigning X blocks
         uint256 withdrawBlockNumber = candidateWithdrawDelay.add(block.number);
-        withdrawsState[msg.sender].caps[withdrawBlockNumber] = withdrawsState[msg.sender].caps[withdrawBlockNumber].add(cap);
+        withdrawsState[msg.sender].caps[withdrawBlockNumber] = withdrawsState[
+            msg.sender
+        ].caps[withdrawBlockNumber].add(cap);
         withdrawsState[msg.sender].blockNumbers.push(withdrawBlockNumber);
         emit Resign(msg.sender, _candidate);
     }
 
     // voteInvalidKYC : any candidate can vote for invalid KYC i.e. a particular candidate's owner has uploaded a bad KYC.
     // On securing 75% votes against an owner ( not candidate ), owner & all its candidates will lose their funds.
-    function voteInvalidKYC(address _invalidCandidate) onlyValidCandidate(msg.sender) onlyValidCandidate(_invalidCandidate) public {
+    function voteInvalidKYC(
+        address _invalidCandidate
+    )
+        public
+        onlyValidCandidate(msg.sender)
+        onlyValidCandidate(_invalidCandidate)
+    {
         address candidateOwner = getCandidateOwner(msg.sender);
         address _invalidMasternode = getCandidateOwner(_invalidCandidate);
         require(!hasVotedInvalid[candidateOwner][_invalidMasternode]);
         hasVotedInvalid[candidateOwner][_invalidMasternode] = true;
         invalidKYCCount[_invalidMasternode] += 1;
-        if( invalidKYCCount[_invalidMasternode]*100/getOwnerCount() >= 75 ){
+        if (
+            (invalidKYCCount[_invalidMasternode] * 100) / getOwnerCount() >= 75
+        ) {
             // 75% owners say that the KYC is invalid
-            address[] memory allMasternodes = new address[](candidates.length-1) ;
+            address[] memory allMasternodes = new address[](
+                candidates.length - 1
+            );
             uint count = 0;
             for (uint i = 0; i < candidates.length; i++) {
                 if (getCandidateOwner(candidates[i]) == _invalidMasternode) {
                     // logic to remove cap.
                     candidateCount = candidateCount.sub(1);
                     allMasternodes[count++] = candidates[i];
-                    delete candidates[i];
                     delete validatorsState[candidates[i]];
+                    delete candidates[i];
                     delete KYCString[_invalidMasternode];
                     delete ownerToCandidate[_invalidMasternode];
                     delete invalidKYCCount[_invalidMasternode];
                 }
             }
+            candidates = removeZeroAddresses(candidates);
             for (uint k = 0; k < owners.length; k++) {
                 if (owners[k] == _invalidMasternode) {
                     delete owners[k];
@@ -263,41 +330,66 @@ contract XDCValidator {
                     break;
                 }
             }
+            owners = removeZeroAddresses(owners);
             emit InvalidatedNode(_invalidMasternode, allMasternodes);
         }
     }
 
     // invalidPercent : get votes against an owner in percentage.
-    function invalidPercent(address _invalidCandidate) onlyValidCandidate(_invalidCandidate) view public returns(uint){
+    function invalidPercent(
+        address _invalidCandidate
+    ) public view onlyValidCandidate(_invalidCandidate) returns (uint) {
         address _invalidMasternode = getCandidateOwner(_invalidCandidate);
-        return (invalidKYCCount[_invalidMasternode]*100/getOwnerCount());
+        return ((invalidKYCCount[_invalidMasternode] * 100) / getOwnerCount());
     }
 
-
     // getOwnerCount : get count of total owners; accounts who own atleast one masternode.
-    function getOwnerCount() view public returns (uint){
+    function getOwnerCount() public view returns (uint) {
         return ownerCount;
     }
 
     // getKYC : get KYC uploaded of the owner of the given masternode or the owner themselves
-    function getLatestKYC(address _address) view public  returns (string) {
+    function getLatestKYC(address _address) public view returns (string) {
         if (isCandidate(_address)) {
-        return KYCString[getCandidateOwner(_address)][KYCString[getCandidateOwner(_address)].length-1];
+            return
-        }
+                KYCString[getCandidateOwner(_address)][
-        else{
+                    KYCString[getCandidateOwner(_address)].length - 1
+                ];
+        } else {
             return KYCString[_address][KYCString[_address].length - 1];
         }
     }
 
-    function getHashCount(address _address) view public returns(uint){
+    function getHashCount(address _address) public view returns (uint) {
         return KYCString[_address].length;
     }
 
-    function withdraw(uint256 _blockNumber, uint _index) public onlyValidWithdraw(_blockNumber, _index) {
+    function withdraw(
+        uint256 _blockNumber,
+        uint _index
+    ) public onlyValidWithdraw(_blockNumber, _index) {
         uint256 cap = withdrawsState[msg.sender].caps[_blockNumber];
         delete withdrawsState[msg.sender].caps[_blockNumber];
         delete withdrawsState[msg.sender].blockNumbers[_index];
         msg.sender.transfer(cap);
         emit Withdraw(msg.sender, _blockNumber, cap);
     }
+
+    function removeZeroAddresses(
+        address[] memory addresses
+    ) private pure returns (address[] memory) {
+        address[] memory newAddresses = new address[](addresses.length);
+        uint256 j = 0;
+        for (uint256 i = 0; i < addresses.length; i++) {
+            if (addresses[i] != address(0)) {
+                newAddresses[j] = addresses[i];
+                j++;
+            }
+        }
+        // Resize the array.
+        assembly {
+            mstore(newAddresses, j)
+        }
+        return newAddresses;
+    }
 }