// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.8.22;

import { AggregatorV3Interface } from "@chainlink/contracts/src/v0.8/shared/interfaces/AggregatorV3Interface.sol";
import { IERC20Metadata } from "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import { IERC165 } from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
import { SafeCast } from "@openzeppelin/contracts/utils/math/SafeCast.sol";
import { ReentrancyGuard } from "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
import { Strings } from "@openzeppelin/contracts/utils/Strings.sol";
import { Comptrollerable } from "@sablier/evm-utils/src/Comptrollerable.sol";
import { ISablierComptroller } from "@sablier/evm-utils/src/interfaces/ISablierComptroller.sol";
import { SafeOracle } from "@sablier/evm-utils/src/libraries/SafeOracle.sol";
import { SafeTokenSymbol } from "@sablier/evm-utils/src/libraries/SafeTokenSymbol.sol";
import { SablierBobState } from "./abstracts/SablierBobState.sol";
import { BobVaultShare } from "./BobVaultShare.sol";
import { IWETH9 } from "./interfaces/external/IWETH9.sol";
import { IBobVaultShare } from "./interfaces/IBobVaultShare.sol";
import { ISablierBob } from "./interfaces/ISablierBob.sol";
import { ISablierBobAdapter } from "./interfaces/ISablierBobAdapter.sol";
import { Errors } from "./libraries/Errors.sol";
import { Bob } from "./types/Bob.sol";

/*

███████╗ █████╗ ██████╗ ██╗     ██╗███████╗██████╗     ██████╗  ██████╗ ██████╗
██╔════╝██╔══██╗██╔══██╗██║     ██║██╔════╝██╔══██╗    ██╔══██╗██╔═══██╗██╔══██╗
███████╗███████║██████╔╝██║     ██║█████╗  ██████╔╝    ██████╔╝██║   ██║██████╔╝
╚════██║██╔══██║██╔══██╗██║     ██║██╔══╝  ██╔══██╗    ██╔══██╗██║   ██║██╔══██╗
███████║██║  ██║██████╔╝███████╗██║███████╗██║  ██║    ██████╔╝╚██████╔╝██████╔╝
╚══════╝╚═╝  ╚═╝╚═════╝ ╚══════╝╚═╝╚══════╝╚═╝  ╚═╝    ╚═════╝  ╚═════╝ ╚═════╝

*/

/// @title SablierBob
/// @notice See the documentation in {ISablierBob}.
contract SablierBob is
    Comptrollerable, // 1 inherited component
    ISablierBob, // 1 inherited component
    ReentrancyGuard, // 1 inherited component
    SablierBobState // 1 inherited component
{
    using SafeCast for uint256;
    using SafeERC20 for IERC20;
    using SafeTokenSymbol for address;
    using Strings for uint256;

    /*//////////////////////////////////////////////////////////////////////////
                                     MODIFIERS
    //////////////////////////////////////////////////////////////////////////*/

    /// @dev Modifier to check that the vault is active.
    modifier onlyActive(uint256 vaultId) {
        _revertIfSettledOrExpired(vaultId);
        _;
    }

    /*//////////////////////////////////////////////////////////////////////////
                                    CONSTRUCTOR
    //////////////////////////////////////////////////////////////////////////*/

    /// @param initialComptroller The address of the initial comptroller contract.
    constructor(address initialComptroller) Comptrollerable(initialComptroller) SablierBobState() { }

    /*//////////////////////////////////////////////////////////////////////////
                          USER-FACING READ-ONLY FUNCTIONS
    //////////////////////////////////////////////////////////////////////////*/

    /// @inheritdoc ISablierBob
    function calculateMinFeeWei(uint256 vaultId) external view override notNull(vaultId) returns (uint256 minFeeWei) {
        // Return 0 if the vault has an adapter, since the fee is taken from yield generated by the adapter.
        if (address(_vaults[vaultId].adapter) != address(0)) {
            return 0;
        }

        // Calculate the minimum fee in wei for the Bob protocol.
        minFeeWei = comptroller.calculateMinFeeWei({ protocol: ISablierComptroller.Protocol.Bob });
    }

    /*//////////////////////////////////////////////////////////////////////////
                        USER-FACING STATE-CHANGING FUNCTIONS
    //////////////////////////////////////////////////////////////////////////*/

    /// @inheritdoc ISablierBob
    function createVault(
        IERC20 token,
        AggregatorV3Interface oracle,
        uint40 expiry,
        uint128 targetPrice
    )
        external
        override
        returns (uint256 vaultId)
    {
        // Check: token is not the zero address.
        if (address(token) == address(0)) {
            revert Errors.SablierBob_TokenAddressZero();
        }

        // Check: token is not the native token.
        if (address(token) == nativeToken) {
            revert Errors.SablierBob_ForbidNativeToken(address(token));
        }

        uint40 currentTimestamp = uint40(block.timestamp);

        // Check: expiry is in the future.
        if (expiry <= currentTimestamp) {
            revert Errors.SablierBob_ExpiryNotInFuture(expiry, currentTimestamp);
        }

        // Check: target price is not zero.
        if (targetPrice == 0) {
            revert Errors.SablierBob_TargetPriceZero();
        }

        // Check: oracle implements the Chainlink {AggregatorV3Interface} interface.
        uint128 latestPrice = SafeOracle.validateOracle(oracle);

        // Check: target price is greater than latest oracle price.
        if (targetPrice <= latestPrice) {
            revert Errors.SablierBob_TargetPriceTooLow(targetPrice, latestPrice);
        }

        // Load the vault ID from storage.
        vaultId = nextVaultId;

        // Effect: bump the next vault ID.
        unchecked {
            nextVaultId = vaultId + 1;
        }

        // Retrieve token symbol and token decimal.
        string memory tokenSymbol = address(token).safeTokenSymbol();
        uint8 tokenDecimals = IERC20Metadata(address(token)).decimals();

        // Effect: deploy the share token for this vault.
        IBobVaultShare shareToken = new BobVaultShare({
            name_: string.concat("Sablier Bob ", tokenSymbol, " Vault #", vaultId.toString()),
            symbol_: string.concat(
                tokenSymbol,
                "-",
                uint256(targetPrice).toString(),
                "-",
                uint256(expiry).toString(),
                "-",
                vaultId.toString()
            ),
            decimals_: tokenDecimals,
            sablierBob: address(this),
            vaultId: vaultId
        });

        // Copy the adapter from storage to memory.
        ISablierBobAdapter adapter = _defaultAdapters[token];

        // Effect: create the vault.
        _vaults[vaultId] = Bob.Vault({
            token: token,
            expiry: expiry,
            lastSyncedAt: currentTimestamp,
            shareToken: shareToken,
            oracle: oracle,
            adapter: adapter,
            isStakedInAdapter: false,
            targetPrice: targetPrice,
            lastSyncedPrice: latestPrice
        });

        // Interaction: register the vault with the adapter.
        if (address(adapter) != address(0)) {
            adapter.registerVault(vaultId);

            // Effect: mark the vault as staked in the adapter.
            _vaults[vaultId].isStakedInAdapter = true;
        }

        // Log the event.
        emit CreateVault(vaultId, token, oracle, adapter, shareToken, targetPrice, expiry);
    }

    /// @inheritdoc ISablierBob
    function enter(uint256 vaultId, uint128 amount)
        external
        override
        nonReentrant
        notNull(vaultId)
        onlyActive(vaultId)
    {
        // Enter the vault.
        _enter({ vaultId: vaultId, from: msg.sender, amount: amount, token: _vaults[vaultId].token });
    }

    /// @inheritdoc ISablierBob
    function enterWithNativeToken(uint256 vaultId)
        external
        payable
        override
        nonReentrant
        notNull(vaultId)
        onlyActive(vaultId)
    {
        // Cache the vault's token.
        address token = address(_vaults[vaultId].token);

        // Interaction: call the deposit function in the vault tokens assuming it follows the IWETH9 interface.
        // Otherwise, it will revert.
        IWETH9(token).deposit{ value: msg.value }();

        // Cast `msg.value` to `uint128`.
        uint128 amount = msg.value.toUint128();

        // Enter the vault.
        _enter({ vaultId: vaultId, from: address(this), amount: amount, token: IERC20(token) });
    }

    /// @inheritdoc ISablierBob
    function redeem(uint256 vaultId)
        external
        payable
        override
        nonReentrant
        notNull(vaultId)
        returns (uint128 transferAmount, uint128 feeAmountDeductedFromYield)
    {
        // If the vault is active, sync the price from the oracle to update the status.
        if (_statusOf(vaultId) == Bob.Status.ACTIVE) {
            // Effect: sync the price from oracle.
            _syncPriceFromOracle(vaultId);

            // If it's still active after the sync, revert.
            if (_statusOf(vaultId) == Bob.Status.ACTIVE) {
                revert Errors.SablierBob_VaultStillActive(vaultId);
            }

            // Otherwise, the vault has been settled.
        }

        // Cache storage variables.
        ISablierBobAdapter adapter = _vaults[vaultId].adapter;
        IBobVaultShare shareToken = _vaults[vaultId].shareToken;
        IERC20 token = _vaults[vaultId].token;

        // Get the caller's share balance.
        uint128 shareBalance = shareToken.balanceOf(msg.sender).toUint128();

        // Check: the share balance is not zero.
        if (shareBalance == 0) {
            revert Errors.SablierBob_NoSharesToRedeem(vaultId, msg.sender);
        }

        // Check if the vault has an adapter.
        if (address(adapter) != address(0)) {
            // Check: the `msg.value` is zero.
            if (msg.value > 0) {
                revert Errors.SablierBob_MsgValueNotZero(vaultId);
            }

            // Check: the deposit token is staked with the adapter.
            if (_vaults[vaultId].isStakedInAdapter) {
                // Effect: set isStakedInAdapter to false.
                _vaults[vaultId].isStakedInAdapter = false;

                // Interaction: unstake all tokens via the adapter.
                _unstakeFullAmountViaAdapter(vaultId, adapter);
            }

            // Interaction: Get the transfer amount and the fee deducted from yield.
            (transferAmount, feeAmountDeductedFromYield) = adapter.processRedemption(vaultId, msg.sender, shareBalance);

            // Interaction: transfer the fee to the comptroller address.
            if (feeAmountDeductedFromYield > 0) {
                token.safeTransfer(address(comptroller), feeAmountDeductedFromYield);
            }
        }
        // Otherwise, check that `msg.value` is greater than or equal to the minimum fee required.
        else {
            // Get the minimum fee from the comptroller.
            ISablierComptroller _comptroller = comptroller;
            uint256 minFeeWei = _comptroller.calculateMinFeeWei({ protocol: ISablierComptroller.Protocol.Bob });

            // Check: `msg.value` is greater than or equal to the minimum fee.
            if (msg.value < minFeeWei) {
                revert Errors.SablierBob_InsufficientFeePayment(msg.value, minFeeWei);
            }

            // Interaction: forward native token fee to comptroller.
            if (msg.value > 0) {
                (bool success,) = address(_comptroller).call{ value: msg.value }("");
                if (!success) {
                    revert Errors.SablierBob_NativeFeeTransferFailed();
                }
            }

            // Return the transfer amount.
            transferAmount = shareBalance;
        }

        // Interaction: burn share tokens from the caller.
        shareToken.burn(vaultId, msg.sender, shareBalance);

        // Interaction: transfer tokens to the caller.
        token.safeTransfer(msg.sender, transferAmount);

        // Log the event.
        emit Redeem({
            vaultId: vaultId,
            user: msg.sender,
            amountReceived: transferAmount,
            sharesBurned: shareBalance,
            fee: feeAmountDeductedFromYield
        });
    }

    /// @inheritdoc ISablierBob
    function setNativeToken(address newNativeToken) external override onlyComptroller {
        // Check: provided token is not zero address.
        if (newNativeToken == address(0)) {
            revert Errors.SablierBob_NativeTokenZeroAddress();
        }

        // Check: native token is not set.
        if (nativeToken != address(0)) {
            revert Errors.SablierBob_NativeTokenAlreadySet(nativeToken);
        }

        // Effect: set the native token.
        nativeToken = newNativeToken;

        // Log the update.
        emit SetNativeToken({ comptroller: msg.sender, nativeToken: newNativeToken });
    }

    /// @inheritdoc ISablierBob
    function setDefaultAdapter(IERC20 token, ISablierBobAdapter newAdapter) external override onlyComptroller {
        // Check: the new adapter implements the {ISablierBobAdapter} interface.
        if (address(newAdapter) != address(0)) {
            bytes4 interfaceId = type(ISablierBobAdapter).interfaceId;
            if (!IERC165(address(newAdapter)).supportsInterface(interfaceId)) {
                revert Errors.SablierBob_NewAdapterMissesInterface(address(newAdapter));
            }
        }

        // Effect: set the default adapter for the token.
        _defaultAdapters[token] = newAdapter;

        // Log the adapter change.
        emit SetDefaultAdapter(token, newAdapter);
    }

    /// @inheritdoc ISablierBob
    function syncPriceFromOracle(uint256 vaultId)
        external
        override
        nonReentrant
        notNull(vaultId)
        onlyActive(vaultId)
        returns (uint128 latestPrice)
    {
        // Effect: sync the price from oracle.
        latestPrice = _syncPriceFromOracle(vaultId);
    }

    /// @inheritdoc ISablierBob
    function unstakeTokensViaAdapter(uint256 vaultId)
        external
        override
        nonReentrant
        notNull(vaultId)
        returns (uint128 amountReceivedFromAdapter)
    {
        // Cache storage variable.
        ISablierBobAdapter adapter = _vaults[vaultId].adapter;

        // Check: the vault has an adapter.
        if (address(adapter) == address(0)) {
            revert Errors.SablierBob_VaultHasNoAdapter(vaultId);
        }

        // Check: the vault has not already been unstaked.
        if (!_vaults[vaultId].isStakedInAdapter) {
            revert Errors.SablierBob_VaultAlreadyUnstaked(vaultId);
        }

        // Check: there is something to unstake.
        if (adapter.getTotalYieldBearingTokenBalance(vaultId) == 0) {
            revert Errors.SablierBob_UnstakeAmountZero(vaultId);
        }

        // If the vault is active, sync the price from the oracle to update the status.
        if (_statusOf(vaultId) == Bob.Status.ACTIVE) {
            // Effect: sync the price from oracle.
            _syncPriceFromOracle(vaultId);

            // If it's still active after the sync, revert.
            if (_statusOf(vaultId) == Bob.Status.ACTIVE) {
                revert Errors.SablierBob_VaultStillActive(vaultId);
            }

            // Otherwise, the vault has been settled.
        }

        // Effect: mark the vault as not staked with the adapter.
        _vaults[vaultId].isStakedInAdapter = false;

        // Interaction: unstake all tokens via the adapter.
        amountReceivedFromAdapter = _unstakeFullAmountViaAdapter(vaultId, adapter);
    }

    /// @inheritdoc ISablierBob
    function onShareTransfer(
        uint256 vaultId,
        address from,
        address to,
        uint256 amount,
        uint256 fromBalanceBefore
    )
        external
        override
    {
        // Check: caller is the share token for this vault.
        if (msg.sender != address(_vaults[vaultId].shareToken)) {
            revert Errors.SablierBob_CallerNotShareToken(vaultId, msg.sender);
        }

        // Cache storage variable.
        ISablierBobAdapter adapter = _vaults[vaultId].adapter;
        if (address(adapter) != address(0)) {
            // Interaction: update staked token holding of the user in the adapter.
            adapter.updateStakedTokenBalance(vaultId, from, to, amount, fromBalanceBefore);
        }
    }

    /*//////////////////////////////////////////////////////////////////////////
                          PRIVATE STATE-CHANGING FUNCTIONS
    //////////////////////////////////////////////////////////////////////////*/

    /// @dev Common function to enter into a vault by depositing tokens into it and minting share tokens to caller.
    /// @param vaultId The ID of the vault to deposit into.
    /// @param from The address holding the vault token when calling this function. In case of native token deposits,
    /// the vault tokens are held by this contract.
    /// @param amount The amount of tokens to deposit.
    /// @param token The ERC-20 token accepted by the vault.
    function _enter(uint256 vaultId, address from, uint128 amount, IERC20 token) private {
        // Check: the deposit amount is not zero.
        if (amount == 0) {
            revert Errors.SablierBob_DepositAmountZero(vaultId, msg.sender);
        }

        // Effect: sync the price from oracle.
        _syncPriceFromOracle(vaultId);

        // Check: the vault is still active after the price sync.
        _revertIfSettledOrExpired(vaultId);

        // Cache storage variables.
        ISablierBobAdapter adapter = _vaults[vaultId].adapter;

        // If adapter is set, transfer tokens to the adapter.
        if (address(adapter) != address(0)) {
            // Interaction: transfer tokens to the adapter. Use `safeTransfer` for the native token path since
            // the contract already holds the wrapped tokens.
            if (from == address(this)) {
                token.safeTransfer(address(adapter), amount);
            } else {
                token.safeTransferFrom(from, address(adapter), amount);
            }

            // Interaction: stake tokens via the adapter on behalf of the caller.
            adapter.stake(vaultId, msg.sender, amount);
        }
        // Otherwise, if `from` is `msg.sender`, transfer tokens to this contract. When this function is called by
        // `enterWithNativeToken`, the vault tokens are held by this contract already.
        else if (from == msg.sender) {
            // Interaction: transfer tokens from caller to this contract.
            token.safeTransferFrom(from, address(this), amount);
        }

        // Interaction: mint share tokens to the caller.
        _vaults[vaultId].shareToken.mint(vaultId, msg.sender, amount);

        // Log the deposit.
        emit Enter({ vaultId: vaultId, user: msg.sender, amountReceived: amount, sharesMinted: amount });
    }

    /// @notice Private function that reverts if the vault is settled or expired.
    /// @param vaultId The ID of the vault.
    function _revertIfSettledOrExpired(uint256 vaultId) private view {
        if (_statusOf(vaultId) != Bob.Status.ACTIVE) {
            revert Errors.SablierBob_VaultNotActive(vaultId);
        }
    }

    /// @dev Private function to fetch the latest oracle price and update it in the vault storage.
    /// @param vaultId The ID of the vault.
    /// @return latestPrice The latest price from the oracle.
    function _syncPriceFromOracle(uint256 vaultId) private returns (uint128 latestPrice) {
        AggregatorV3Interface oracleAddress = _vaults[vaultId].oracle;

        // Get the latest price, normalized to 8 decimals, from the oracle with safety checks.
        (latestPrice,,) = SafeOracle.safeOraclePrice({ oracle: oracleAddress, normalize: true });

        // Return if the latest price is zero.
        if (latestPrice == 0) {
            return 0;
        }

        uint40 currentTimestamp = uint40(block.timestamp);

        // Effect: update the last synced price and timestamp.
        _vaults[vaultId].lastSyncedPrice = latestPrice;
        _vaults[vaultId].lastSyncedAt = currentTimestamp;

        // Log the event.
        emit SyncPriceFromOracle({
            vaultId: vaultId,
            oracle: oracleAddress,
            latestPrice: latestPrice,
            syncedAt: currentTimestamp
        });
    }

    /// @dev Private function to unstake all tokens using the adapter.
    /// @param vaultId The ID of the vault.
    /// @param adapter The adapter to use for unstaking.
    /// @return amountReceivedFromAdapter The amount of tokens received from the adapter after unstaking.
    function _unstakeFullAmountViaAdapter(
        uint256 vaultId,
        ISablierBobAdapter adapter
    )
        private
        returns (uint128 amountReceivedFromAdapter)
    {
        uint128 wrappedTokenUnstakedAmount;

        // Interaction: unstake all tokens via the adapter.
        (wrappedTokenUnstakedAmount, amountReceivedFromAdapter) = adapter.unstakeFullAmount(vaultId);

        // Log the event.
        emit UnstakeFromAdapter(vaultId, adapter, wrappedTokenUnstakedAmount, amountReceivedFromAdapter);
    }
}