// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

import "./IAdventurous.sol";
import "./AdventureWhitelist.sol";
import "../token/erc721/ERC721OpenZeppelin.sol";

/**
 * @title AdventureBase
 * @author Limit Break, Inc.
 * @notice Base functionality of the AdventureERC721 token standard.
 */
abstract contract AdventureBase is AdventureWhitelist, IAdventurous {

    error AdventureERC721__AdventureApprovalToCaller();
    error AdventureERC721__AlreadyOnQuest();
    error AdventureERC721__AnActiveQuestIsPreventingTransfers();
    error AdventureERC721__CallerNotApprovedForAdventure();
    error AdventureERC721__CallerNotTokenOwner();
    error AdventureERC721__MaxSimultaneousQuestsCannotBeZero();
    error AdventureERC721__MaxSimultaneousQuestsExceeded();
    error AdventureERC721__NotOnQuest();
    error AdventureERC721__QuestIdOutOfRange();
    error AdventureERC721__TooManyActiveQuests();

    /// @notice Specifies an upper bound for the maximum number of simultaneous quests per adventure.
    uint256 private constant MAX_CONCURRENT_QUESTS = 100;

    /// @dev A value denoting a transfer originating from transferFrom or safeTransferFrom
    uint256 internal constant TRANSFERRING_VIA_ERC721 = 1;

    /// @dev A value denoting a transfer originating from adventureTransferFrom or adventureSafeTransferFrom
    uint256 internal constant TRANSFERRING_VIA_ADVENTURE = 2;

    /// @dev The most simultaneous quests the token may participate in at a time
    uint256 private _maxSimultaneousQuests;

    /// @dev Specifies the type of transfer that is actively being used
    uint256 internal transferType;

    /// @dev Maps each token id to the number of blocking quests it is currently entered into
    mapping (uint256 => uint256) internal blockingQuestCounts;

    /// @dev Mapping from owner to operator approvals for special gameplay behavior
    mapping (address => mapping (address => bool)) private operatorAdventureApprovals;

    /// @dev Maps each token id to a mapping that can enumerate all active quests within an adventure
    mapping (uint256 => mapping (address => uint32[])) public activeQuestList;

    /// @dev Maps each token id to a mapping from adventure address to a mapping of quest ids to quest details
    mapping (uint256 => mapping (address => mapping (uint32 => Quest))) public activeQuestLookup;

    /// @notice Transfers a player's token if they have opted into an authorized, whitelisted adventure.
    function adventureTransferFrom(address from, address to, uint256 tokenId) external override {
        _requireCallerIsWhitelistedAdventure();
        _requireCallerApprovedForAdventure(tokenId);
        transferType = TRANSFERRING_VIA_ADVENTURE;
        _doTransfer(from, to, tokenId);
        transferType = TRANSFERRING_VIA_ERC721;
    }

    /// @notice Safe transfers a player's token if they have opted into an authorized, whitelisted adventure.
    function adventureSafeTransferFrom(address from, address to, uint256 tokenId) external override {
        _requireCallerIsWhitelistedAdventure();
        _requireCallerApprovedForAdventure(tokenId);
        transferType = TRANSFERRING_VIA_ADVENTURE;
        _doSafeTransfer(from, to, tokenId, "");
        transferType = TRANSFERRING_VIA_ERC721;
    }

    /// @notice Burns a player's token if they have opted into an authorized, whitelisted adventure.
    function adventureBurn(uint256 tokenId) external override {
        _requireCallerIsWhitelistedAdventure();
        _requireCallerApprovedForAdventure(tokenId);
        transferType = TRANSFERRING_VIA_ADVENTURE;
        _doBurn(tokenId);
        transferType = TRANSFERRING_VIA_ERC721;
    }

    /// @notice Enters a player's token into a quest if they have opted into an authorized, whitelisted adventure.
    function enterQuest(uint256 tokenId, uint256 questId) external override {
        _requireCallerIsWhitelistedAdventure();
        _requireCallerApprovedForAdventure(tokenId);
        _enterQuest(tokenId, _msgSender(), questId);
    }

    /// @notice Exits a player's token from a quest if they have opted into an authorized, whitelisted adventure.
    /// For developers of adventure contracts that perform adventure burns, be aware that the adventure must exitQuest
    /// before the adventure burn occurs, as _exitQuest emits the owner of the token, which would revert after burning.
    function exitQuest(uint256 tokenId, uint256 questId) external override {
        _requireCallerIsWhitelistedAdventure();
        _requireCallerApprovedForAdventure(tokenId);
        _exitQuest(tokenId, _msgSender(), questId);
    }

    /// @notice Admin-only ability to boot a token from all quests on an adventure.
    /// This ability is only unlocked in the event that an adventure has been unwhitelisted, as early exiting
    /// from quests can cause out of sync state between the ERC721 token contract and the adventure/quest.
    function bootFromAllQuests(uint256 tokenId, address adventure) external {
        _requireCallerIsContractOwner();
        _requireAdventureRemovedFromWhitelist(adventure);
        _exitAllQuests(tokenId, adventure, true);
    }

    /// @notice Gives the player the ability to exit a quest without interacting directly with the approved, whitelisted adventure
    /// This ability is only unlocked in the event that an adventure has been unwhitelisted, as early exiting
    /// from quests can cause out of sync state between the ERC721 token contract and the adventure/quest.
    function userExitQuest(uint256 tokenId, address adventure, uint256 questId) external {
        _requireAdventureRemovedFromWhitelist(adventure);
        _requireCallerOwnsToken(tokenId);
        _exitQuest(tokenId, adventure, questId);
    }

    /// @notice Gives the player the ability to exit all quests on an adventure without interacting directly with the approved, whitelisted adventure
    /// This ability is only unlocked in the event that an adventure has been unwhitelisted, as early exiting
    /// from quests can cause out of sync state between the ERC721 token contract and the adventure/quest.
    function userExitAllQuests(uint256 tokenId, address adventure) external {
        _requireAdventureRemovedFromWhitelist(adventure);
        _requireCallerOwnsToken(tokenId);
        _exitAllQuests(tokenId, adventure, false);
    }

    /// @notice Similar to {IERC721-setApprovalForAll}, but for special in-game adventures only
    function setAdventuresApprovedForAll(address operator, bool approved) external {
        address tokenOwner = _msgSender();

        if(tokenOwner == operator) {
            revert AdventureERC721__AdventureApprovalToCaller();
        }
        operatorAdventureApprovals[tokenOwner][operator] = approved;
        emit AdventureApprovalForAll(tokenOwner, operator, approved);
    }

    /// @notice Similar to {IERC721-isApprovedForAll}, but for special in-game adventures only
    function areAdventuresApprovedForAll(address owner_, address operator) public view returns (bool) {
        return operatorAdventureApprovals[owner_][operator];
    }    
    
    /// @notice Returns the number of quests a token is actively participating in for a specified adventure
    function getQuestCount(uint256 tokenId, address adventure) public override view returns (uint256) {
        return activeQuestList[tokenId][adventure].length;
    }

    /// @notice Returns the amount of time a token has been participating in the specified quest
    function getTimeOnQuest(uint256 tokenId, address adventure, uint256 questId) public override view returns (uint256) {
        (bool participatingInQuest, uint256 startTimestamp,) = isParticipatingInQuest(tokenId, adventure, questId);
        return participatingInQuest ? (block.timestamp - startTimestamp) : 0;
    } 

    /// @notice Returns whether or not a token is currently participating in the specified quest as well as the time it was started and the quest index
    function isParticipatingInQuest(uint256 tokenId, address adventure, uint256 questId) public override view returns (bool participatingInQuest, uint256 startTimestamp, uint256 index) {
        if(questId > type(uint32).max) {
            revert AdventureERC721__QuestIdOutOfRange();
        }

        Quest storage quest = activeQuestLookup[tokenId][adventure][uint32(questId)];
        participatingInQuest = quest.isActive;
        startTimestamp = quest.startTimestamp;
        index = quest.arrayIndex;
        return (participatingInQuest, startTimestamp, index);
    }

    /// @notice Returns a list of all active quests for the specified token id and adventure
    function getActiveQuests(uint256 tokenId, address adventure) public override view returns (Quest[] memory activeQuests) {
        uint256 questCount = getQuestCount(tokenId, adventure);
        activeQuests = new Quest[](questCount);
        uint32[] memory activeQuestIdList = activeQuestList[tokenId][adventure];

        for(uint256 i = 0; i < questCount; ++i) {
            activeQuests[i] = activeQuestLookup[tokenId][adventure][activeQuestIdList[i]];
        }

        return activeQuests;
    }

    function maxSimultaneousQuests() public virtual view returns (uint256) {
        return _maxSimultaneousQuests;
    }

    /// @dev Enters the specified quest for a token id.
    /// Throws if the token is already participating in the specified quest.
    /// Throws if the number of active quests exceeds the max allowable for the given adventure.
    /// Emits a QuestUpdated event for off-chain processing.
    function _enterQuest(uint256 tokenId, address adventure, uint256 questId) internal {
        (bool participatingInQuest,,) = isParticipatingInQuest(tokenId, adventure, questId);
        if(participatingInQuest) {
            revert AdventureERC721__AlreadyOnQuest();
        }

        uint256 currentQuestCount = getQuestCount(tokenId, adventure);
        if(currentQuestCount >= maxSimultaneousQuests()) {
            revert AdventureERC721__TooManyActiveQuests();
        }

        uint32 castedQuestId = uint32(questId);
        activeQuestList[tokenId][adventure].push(castedQuestId);
        activeQuestLookup[tokenId][adventure][castedQuestId].isActive = true;
        activeQuestLookup[tokenId][adventure][castedQuestId].startTimestamp = uint64(block.timestamp);
        activeQuestLookup[tokenId][adventure][castedQuestId].questId = castedQuestId;
        activeQuestLookup[tokenId][adventure][castedQuestId].arrayIndex = uint32(currentQuestCount);

        address ownerOfToken = _ownerOfToken(tokenId);
        emit QuestUpdated(tokenId, ownerOfToken, adventure, questId, true, false);

        if(IAdventure(adventure).questsLockTokens()) {
            unchecked {
                ++blockingQuestCounts[tokenId];
            }
        }

        // Invoke callback to the adventure to facilitate state synchronization as needed
        IAdventure(adventure).onQuestEntered(ownerOfToken, tokenId, questId);
    }

    /// @dev Exits the specified quest for a token id.
    /// Throws if the token is not currently participating on the specified quest.
    /// Emits a QuestUpdated event for off-chain processing.
    function _exitQuest(uint256 tokenId, address adventure, uint256 questId) internal {
        (bool participatingInQuest, uint256 startTimestamp, uint256 index) = isParticipatingInQuest(tokenId, adventure, questId);
        if(!participatingInQuest) {
            revert AdventureERC721__NotOnQuest();
        }

        uint32 castedQuestId = uint32(questId);
        uint256 lastArrayIndex = getQuestCount(tokenId, adventure) - 1;
        if(index != lastArrayIndex) {
            activeQuestList[tokenId][adventure][index] = activeQuestList[tokenId][adventure][lastArrayIndex];
            activeQuestLookup[tokenId][adventure][activeQuestList[tokenId][adventure][lastArrayIndex]].arrayIndex = uint32(index);
        }

        activeQuestList[tokenId][adventure].pop();
        delete activeQuestLookup[tokenId][adventure][castedQuestId];

        address ownerOfToken = _ownerOfToken(tokenId);
        emit QuestUpdated(tokenId, ownerOfToken, adventure, questId, false, false);

        if(IAdventure(adventure).questsLockTokens()) {
            --blockingQuestCounts[tokenId];
        }

        // Invoke callback to the adventure to facilitate state synchronization as needed
        IAdventure(adventure).onQuestExited(ownerOfToken, tokenId, questId, startTimestamp);
    }

    /// @dev Removes the specified token id from all quests on the specified adventure
    function _exitAllQuests(uint256 tokenId, address adventure, bool booted) internal {
        address tokenOwner = _ownerOfToken(tokenId);
        uint256 questCount = getQuestCount(tokenId, adventure);

        if(IAdventure(adventure).questsLockTokens()) {
            blockingQuestCounts[tokenId] -= questCount;
        }

        for(uint256 i = 0; i < questCount;) {
            uint32 questId = activeQuestList[tokenId][adventure][i];

            Quest memory quest = activeQuestLookup[tokenId][adventure][questId];
            uint256 startTimestamp = quest.startTimestamp;

            emit QuestUpdated(tokenId, tokenOwner, adventure, questId, false, booted);
            delete activeQuestLookup[tokenId][adventure][questId];
            
            // Invoke callback to the adventure to facilitate state synchronization as needed
            IAdventure(adventure).onQuestExited(tokenOwner, tokenId, questId, startTimestamp);

            unchecked {
                ++i;
            }
        }

        delete activeQuestList[tokenId][adventure];
    }

    /// @dev Validates that the caller is approved for adventure on the specified token id
    /// Throws when the caller has not been approved by the user.
    function _requireCallerApprovedForAdventure(uint256 tokenId) internal view {
        if(!areAdventuresApprovedForAll(_ownerOfToken(tokenId), _msgSender())) {
            revert AdventureERC721__CallerNotApprovedForAdventure();
        }
    }

    /// @dev Validates that the caller owns the specified token
    /// Throws when the caller does not own the specified token.
    function _requireCallerOwnsToken(uint256 tokenId) internal view {
        if(_ownerOfToken(tokenId) != _msgSender()) {
            revert AdventureERC721__CallerNotTokenOwner();
        }
    }

    /// @dev Validates that the specified value of max simultaneous quests is in range [1-MAX_CONCURRENT_QUESTS]
    /// Throws when `maxSimultaneousQuests_` is zero.
    /// Throws when `maxSimultaneousQuests_` is more than MAX_CONCURRENT_QUESTS.
    function _validateMaxSimultaneousQuests(uint256 maxSimultaneousQuests_) internal pure {
        if(maxSimultaneousQuests_ == 0) {
            revert AdventureERC721__MaxSimultaneousQuestsCannotBeZero();
        }

        if(maxSimultaneousQuests_ > MAX_CONCURRENT_QUESTS) {
            revert AdventureERC721__MaxSimultaneousQuestsExceeded();
        }
    }

    function _setMaxSimultaneousQuestsAndInitializeTransferType(uint256 maxSimultaneousQuests_) internal {
        _validateMaxSimultaneousQuests(maxSimultaneousQuests_);
        _maxSimultaneousQuests = maxSimultaneousQuests_;
        transferType = TRANSFERRING_VIA_ERC721;
    }

    function _doBurn(uint256 tokenId) internal virtual;

    function _doTransfer(address from, address to, uint256 tokenId) internal virtual;

    function _doSafeTransfer(address from, address to, uint256 tokenId, bytes memory data) internal virtual;

    function _ownerOfToken(uint256 tokenId) internal view virtual returns (address);
}


/**
 * @title AdventureERC721
 * @author Limit Break, Inc.
 * @notice Standard AdventureERC721 implementation allowing for constructor to be called
 */
abstract contract AdventureERC721 is AdventureBase, ERC721OpenZeppelin {

    /// @dev The most simultaneous quests the token may participate in at a time
    uint256 private immutable _maxSimultaneousQuestsImmutable;

    constructor(uint256 maxSimultaneousQuests_) {
        _setMaxSimultaneousQuestsAndInitializeTransferType(maxSimultaneousQuests_);
        _maxSimultaneousQuestsImmutable = maxSimultaneousQuests_;
    }

    /// @dev ERC-165 interface support
    function supportsInterface(bytes4 interfaceId) public view virtual override (ERC721, IERC165) returns (bool) {
        return 
        interfaceId == type(IAdventurous).interfaceId || 
        super.supportsInterface(interfaceId);
    }

    function maxSimultaneousQuests() public view override returns (uint256) {
        return _maxSimultaneousQuestsImmutable;
    }

    function _doBurn(uint256 tokenId) internal virtual override {
        _burn(tokenId);
    }

    function _doTransfer(address from, address to, uint256 tokenId) internal virtual override {
        _transfer(from, to, tokenId);
    }

    function _doSafeTransfer(address from, address to, uint256 tokenId, bytes memory data) internal virtual override {
        _safeTransfer(from, to, tokenId, data);
    }

    function _ownerOfToken(uint256 tokenId) internal view virtual override returns (address) {
        return ownerOf(tokenId);
    }

    /// @dev By default, tokens that are participating in quests are transferrable.  However, if a token is participating
    /// in a quest on an adventure that was designated as a token locker, the transfer will revert and keep the token
    /// locked.
    function _beforeTokenTransfer(address /*from*/, address /*to*/, uint256 firstTokenId, uint256 batchSize) internal virtual override {
        for (uint256 i = 0; i < batchSize;) {
            if(blockingQuestCounts[firstTokenId + i] > 0) {
                revert AdventureERC721__AnActiveQuestIsPreventingTransfers();
            }

            unchecked {
                ++i;
            }
        }
    }
}

/**
 * @title AdventureERC721Initializable
 * @author Limit Break, Inc.
 * @notice Initializable AdventureERC721 implementation allowing for EIP-1167 clones.
 */
abstract contract AdventureERC721Initializable is AdventureBase, ERC721OpenZeppelinInitializable {

    error AdventureERC721Initializable__AlreadyInitializedMaxSimultaneousQuestsAndTransferType();

    bool private _maxSimultaneousQuestsInitialized;

    function initializeMaxSimultaneousQuestsAndTransferType(uint256 maxSimultaneousQuests_) public {
        _requireCallerIsContractOwner();

        if(_maxSimultaneousQuestsInitialized) {
            revert AdventureERC721Initializable__AlreadyInitializedMaxSimultaneousQuestsAndTransferType();
        }

        _maxSimultaneousQuestsInitialized = true;

        _setMaxSimultaneousQuestsAndInitializeTransferType(maxSimultaneousQuests_);
    }

    /// @dev ERC-165 interface support
    function supportsInterface(bytes4 interfaceId) public view virtual override (ERC721, IERC165) returns (bool) {
        return 
        interfaceId == type(IAdventurous).interfaceId || 
        super.supportsInterface(interfaceId);
    }

    function _doBurn(uint256 tokenId) internal virtual override {
        _burn(tokenId);
    }

    function _doTransfer(address from, address to, uint256 tokenId) internal virtual override {
        _transfer(from, to, tokenId);
    }

    function _doSafeTransfer(address from, address to, uint256 tokenId, bytes memory data) internal virtual override {
        _safeTransfer(from, to, tokenId, data);
    }

    function _ownerOfToken(uint256 tokenId) internal view virtual override returns (address) {
        return ownerOf(tokenId);
    }

    /// @dev By default, tokens that are participating in quests are transferrable.  However, if a token is participating
    /// in a quest on an adventure that was designated as a token locker, the transfer will revert and keep the token
    /// locked.
    function _beforeTokenTransfer(address /*from*/, address /*to*/, uint256 firstTokenId, uint256 batchSize) internal virtual override {
        for (uint256 i = 0; i < batchSize;) {
            if(blockingQuestCounts[firstTokenId + i] > 0) {
                revert AdventureERC721__AnActiveQuestIsPreventingTransfers();
            }

            unchecked {
                ++i;
            }
        }
    }
}