// File: /C/Users/nejcs/Desktop/JOB/seascape-smartcontracts/contracts/nft_swap/swap_params/ScapeSwapParams.sol



pragma solidity 0.6.7;
pragma experimental ABIEncoderV2;

import "./../../openzeppelin/contracts/access/Ownable.sol";

/// @title ScapeSwapParams is nft params encoder/decoder, signature verifyer
/// @author Nejc Schneider
contract ScapeSwapParams is Ownable{

    // takes in _encodedData and converts to seascape
    function metadataIsValid (uint256 _offerId, bytes memory _encodedData,
      uint8 v, bytes32 r, bytes32 s) public view returns (bool){

      (uint256 imgId, uint256 generation, uint8 quality) = decodeParams(_encodedData);

      bytes32 hash = this.encodeParams(_offerId, imgId, generation, quality);

      address signer = ecrecover(hash, v, r, s);
      require(signer == owner(),  "Verification failed");

    	return true;
    }

    function encodeParams(
        uint256 _offerId,
        uint256 _imgId,
        uint256 _generation,
        uint8 _quality
    )
        public
        view
        returns (bytes32 message)
    {
        bytes memory prefix = "\x19Ethereum Signed Message:\n32";
        bytes32 messageNoPrefix = keccak256(abi
            .encode(_offerId, _imgId, _generation, _quality));
        bytes32 hash = keccak256(abi.encodePacked(prefix, messageNoPrefix));

        return hash;
    }

    function decodeParams (bytes memory _encodedData)
        public
        view
        returns (
            uint256 imgId,
            uint256 generation,
            uint8 quality
        )
    {
        (uint256 imgId, uint256 generation, uint8 quality) = abi
            .decode(_encodedData, (uint256, uint256, uint8));

        return (imgId, generation, quality);
    }


}

// File: /C/Users/nejcs/Desktop/JOB/seascape-smartcontracts/contracts/openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

import "../GSN/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

// File: /C/Users/nejcs/Desktop/JOB/seascape-smartcontracts/contracts/openzeppelin/contracts/GSN/Context.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}