// SPDX-License-Identifier: UNLICENSED
pragma solidity 0.8.18;

import "./SmartAssetBase.sol";
import "../Interfaces/ISmartAssetSoulbound.sol";

/**
 * @title SmartAssetSoulbound.
 * @author Arianee - Dynamic NFTs for real-world use cases and consumer engagement (www.arianee.org).
 */
abstract contract SmartAssetSoulbound is SmartAssetBase, ISmartAssetSoulbound {
    /**
     * @notice SOULBOUND_FEATURE: dummy bytes32 to be used as a feature flag. It is needed to be able to use the {IERC165-supportsInterface} function.
     */
    bytes32 public constant SOULBOUND_FEATURE = keccak256("SOULBOUND_FEATURE");

    /**
     * @dev See {SmartAssetBase-requestToken}.
     */
    function requestToken(
        uint256 tokenId,
        bytes calldata signature,
        address newOwner,
        bool keepTransferKey,
        address walletProvider
    ) public virtual override whenNotPaused {
        require(keepTransferKey == false, "SmartAssetSoulbound: Forbidden to keep the transfer key");
        super.requestToken(tokenId, signature, newOwner, keepTransferKey, walletProvider);
    }

    /**
     * @dev See {SmartAssetBase-setTokenTransferKey}.
     */
    function setTokenTransferKey(uint256 tokenId, address key) public virtual override isApprovedOrOwner(_msgSender(), tokenId) whenNotPaused {
        address owner = super.ownerOf(tokenId);
        address issuer = super.footprintOf(tokenId).issuer;
        require(owner == issuer, "SmartAssetSoulbound: Only the issuer can set the transfer key");

        super.setTokenTransferKey(tokenId, key);
    }

    /**
     * @dev See {SmartAssetBase-_transfer}
     */
    function _transfer(address from, address to, uint256 tokenId) internal virtual override {
        address owner = super.ownerOf(tokenId);
        address issuer = super.footprintOf(tokenId).issuer;

        // If the owner is NOT the issuer, the token is soulbound and the transfer can be made only by the issuer to change the owner if needed
        if (owner != issuer) {
            require(issuer == _msgSender(), "SmartAssetSoulbound: Only the issuer can transfer the token");
        }

        /**
         * If the previous condition has not been hit, the owner IS the issuer and the token is not soulbound yet or not anymore for a limited time.
         * This is either the first transfer of the token to its first "real" owner or a recovery request made by the issuer on the behalf of the owner (i.e the owner lost his wallet and wants to recover his token)
         */

        super._transfer(from, to, tokenId);
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(ISmartAssetSoulbound).interfaceId || super.supportsInterface(interfaceId);
    }
}