// File: src/Fig.sol



// SPDX-License-Identifier: Unlicense
pragma solidity ^0.8.16;

import {IChronicle} from "chronicle-std/IChronicle.sol";
import {Auth} from "chronicle-std/auth/Auth.sol";
import {Toll} from "chronicle-std/toll/Toll.sol";

import {IChainlink} from "./IChainlink.sol";

interface IMakerMedianizer is IChronicle {
    /// @notice Returns the age of the current value.
    /// @return age The age of the current value.
    function age() external view returns (uint32 age);
}

/**
 * @title Fig
 * @custom:version 0.1.0
 *
 * @notice Fig provides Chainlink compatible interfaces for consuming Maker
 *         medianizers.
 */
contract Fig is IChainlink, Auth, Toll {
    /// @notice This is the legacy (i.e. Maker) medianizer contract
    address public immutable medianizer;

    constructor(address medianizer_) {
        medianizer = medianizer_;
    }

    /// @inheritdoc IChainlink
    uint8 public constant decimals = 8;

    /// @inheritdoc IChainlink
    /// @dev Will revert on overflow, solc 0.8+
    function latestAnswer() external view toll returns (int) {
        return int(IMakerMedianizer(medianizer).read() / 10**10);
    }

    /// @inheritdoc IChainlink
    /// @notice Where we don't have corollaries for all of the values below,
    //          we return 0.
    function latestRoundData()
        external
        view
        toll
        returns (
            uint80 roundId,
            int answer,
            uint startedAt,
            uint updatedAt,
            uint80 answeredInRound
        ) {
            answeredInRound = roundId = 1;
            answer = int(IMakerMedianizer(medianizer).read() / 10**10);
            startedAt = 0;
            updatedAt = uint(IMakerMedianizer(medianizer).age());
    }

    // -- Overridden Toll Functions --

    /// @dev Defines authorization for IToll's authenticated functions.
    function toll_auth() internal override(Toll) auth {}
}

// File: lib/chronicle-std/src/IChronicle.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.16;

/**
 * @title IChronicle
 *
 * @notice Interface for Chronicle Protocol's oracle products
 */
interface IChronicle {
    /// @notice Returns the oracle's identifier.
    /// @return wat The oracle's identifier.
    function wat() external view returns (bytes32 wat);

    /// @notice Returns the oracle's current value.
    /// @dev Reverts if no value set.
    /// @return value The oracle's current value.
    function read() external view returns (uint value);

    /// @notice Returns the oracle's current value and its age.
    /// @dev Reverts if no value set.
    /// @return value The oracle's current value.
    /// @return age The value's age.
    function readWithAge() external view returns (uint value, uint age);

    /// @notice Returns the oracle's current value.
    /// @return isValid True if value exists, false otherwise.
    /// @return value The oracle's current value if it exists, zero otherwise.
    function tryRead() external view returns (bool isValid, uint value);

    /// @notice Returns the oracle's current value and its age.
    /// @return isValid True if value exists, false otherwise.
    /// @return value The oracle's current value if it exists, zero otherwise.
    /// @return age The value's age if value exists, zero otherwise.
    function tryReadWithAge()
        external
        view
        returns (bool isValid, uint value, uint age);
}

// File: lib/chronicle-std/src/auth/Auth.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.16;

import {IAuth} from "./IAuth.sol";

/**
 * @title Auth Module
 *
 * @dev The `Auth` contract module provides a basic access control mechanism,
 *      where a set of addresses are granted access to protected functions.
 *      These addresses are said to be _auth'ed_.
 *
 *      Initially, the deployer address is the only address auth'ed. Through
 *      the `rely(address)` and `deny(address)` functions, auth'ed callers are
 *      able to grant/renounce auth to/from addresses.
 *
 *      This module is used through inheritance. It will make available the
 *      modifier `auth`, which can be applied to functions to restrict their
 *      use to only auth'ed callers.
 */
abstract contract Auth is IAuth {
    /// @dev Mapping storing whether address is auth'ed.
    /// @custom:invariant Image of mapping is {0, 1}.
    ///                     ∀x ∊ Address: _wards[x] ∊ {0, 1}
    /// @custom:invariant Only deployer address authenticated after deployment.
    ///                     deployment → (∀x ∊ Address: _wards[x] == 1 → x == msg.sender)
    /// @custom:invariant Only functions `rely` and `deny` may mutate the mapping's state.
    ///                     ∀x ∊ Address: preTx(_wards[x]) != postTx(_wards[x])
    ///                                     → (msg.sig == "rely" ∨ msg.sig == "deny")
    /// @custom:invariant Mapping's state may only be mutated by authenticated caller.
    ///                     ∀x ∊ Address: preTx(_wards[x]) != postTx(_wards[x]) → _wards[msg.sender] = 1
    mapping(address => uint) private _wards;

    /// @dev List of addresses possibly being auth'ed.
    /// @dev May contain duplicates.
    /// @dev May contain addresses not being auth'ed anymore.
    /// @custom:invariant Every address being auth'ed once is element of the list.
    ///                     ∀x ∊ Address: authed(x) -> x ∊ _wardsTouched
    address[] private _wardsTouched;

    /// @dev Ensures caller is auth'ed.
    modifier auth() {
        assembly ("memory-safe") {
            // Compute slot of _wards[msg.sender].
            mstore(0x00, caller())
            mstore(0x20, _wards.slot)
            let slot := keccak256(0x00, 0x40)

            // Revert if caller not auth'ed.
            let isAuthed := sload(slot)
            if iszero(isAuthed) {
                // Store selector of `NotAuthorized(address)`.
                mstore(0x00, 0x4a0bfec1)
                // Store msg.sender.
                mstore(0x20, caller())
                // Revert with (offset, size).
                revert(0x1c, 0x24)
            }
        }
        _;
    }

    constructor() {
        _wards[msg.sender] = 1;
        _wardsTouched.push(msg.sender);

        // Note to use address(0) as caller to keep invariant that no address
        // can grant itself auth.
        emit AuthGranted(address(0), msg.sender);
    }

    /// @inheritdoc IAuth
    function rely(address who) external auth {
        if (_wards[who] == 1) return;

        _wards[who] = 1;
        _wardsTouched.push(who);
        emit AuthGranted(msg.sender, who);
    }

    /// @inheritdoc IAuth
    function deny(address who) external auth {
        if (_wards[who] == 0) return;

        _wards[who] = 0;
        emit AuthRenounced(msg.sender, who);
    }

    /// @inheritdoc IAuth
    function authed(address who) public view returns (bool) {
        return _wards[who] == 1;
    }

    /// @inheritdoc IAuth
    /// @custom:invariant Only contains auth'ed addresses.
    ///                     ∀x ∊ authed(): _wards[x] == 1
    /// @custom:invariant Contains all auth'ed addresses.
    ///                     ∀x ∊ Address: _wards[x] == 1 → x ∊ authed()
    function authed() public view returns (address[] memory) {
        // Initiate array with upper limit length.
        address[] memory wardsList = new address[](_wardsTouched.length);

        // Iterate through all possible auth'ed addresses.
        uint ctr;
        for (uint i; i < wardsList.length; i++) {
            // Add address only if still auth'ed.
            if (_wards[_wardsTouched[i]] == 1) {
                wardsList[ctr++] = _wardsTouched[i];
            }
        }

        // Set length of array to number of auth'ed addresses actually included.
        assembly ("memory-safe") {
            mstore(wardsList, ctr)
        }

        return wardsList;
    }

    /// @inheritdoc IAuth
    function wards(address who) public view returns (uint) {
        return _wards[who];
    }
}

// File: lib/chronicle-std/src/toll/Toll.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.16;

import {IToll} from "./IToll.sol";

/**
 * @title Toll Module
 *
 * @notice "Toll paid, we kiss - but dissension looms, maybe diss?"
 *
 * @dev The `Toll` contract module provides a basic access control mechanism,
 *      where a set of addresses are granted access to protected functions.
 *      These addresses are said the be _tolled_.
 *
 *      Initially, no address is tolled. Through the `kiss(address)` and
 *      `diss(address)` functions, auth'ed callers are able to toll/de-toll
 *      addresses. Authentication for these functions is defined via the
 *      downstream implemented `toll_auth()` function.
 *
 *      This module is used through inheritance. It will make available the
 *      modifier `toll`, which can be applied to functions to restrict their
 *      use to only tolled callers.
 */
abstract contract Toll is IToll {
    /// @dev Mapping storing whether address is tolled.
    /// @custom:invariant Image of mapping is {0, 1}.
    ///                     ∀x ∊ Address: _buds[x] ∊ {0, 1}
    /// @custom:invariant Only functions `kiss` and `diss` may mutate the mapping's state.
    ///                     ∀x ∊ Address: preTx(_buds[x]) != postTx(_buds[x])
    ///                                     → (msg.sig == "kiss" ∨ msg.sig == "diss")
    /// @custom:invariant Mapping's state may only be mutated by authenticated caller.
    ///                     ∀x ∊ Address: preTx(_buds[x]) != postTx(_buds[x])
    ///                                     → toll_auth()
    mapping(address => uint) private _buds;

    /// @dev List of addresses possibly being tolled.
    /// @dev May contain duplicates.
    /// @dev May contain addresses not being tolled anymore.
    /// @custom:invariant Every address being tolled once is element of the list.
    ///                     ∀x ∊ Address: tolled(x) → x ∊ _budsTouched
    address[] private _budsTouched;

    /// @dev Ensures caller is tolled.
    modifier toll() {
        assembly ("memory-safe") {
            // Compute slot of _buds[msg.sender].
            mstore(0x00, caller())
            mstore(0x20, _buds.slot)
            let slot := keccak256(0x00, 0x40)

            // Revert if caller not tolled.
            let isTolled := sload(slot)
            if iszero(isTolled) {
                // Store selector of `NotTolled(address)`.
                mstore(0x00, 0xd957b595)
                // Store msg.sender.
                mstore(0x20, caller())
                // Revert with (offset, size).
                revert(0x1c, 0x24)
            }
        }
        _;
    }

    /// @dev Reverts if caller not allowed to access protected function.
    /// @dev Must be implemented in downstream contract.
    function toll_auth() internal virtual;

    /// @inheritdoc IToll
    function kiss(address who) external {
        toll_auth();

        if (_buds[who] == 1) return;

        _buds[who] = 1;
        _budsTouched.push(who);
        emit TollGranted(msg.sender, who);
    }

    /// @inheritdoc IToll
    function diss(address who) external {
        toll_auth();

        if (_buds[who] == 0) return;

        _buds[who] = 0;
        emit TollRenounced(msg.sender, who);
    }

    /// @inheritdoc IToll
    function tolled(address who) public view returns (bool) {
        return _buds[who] == 1;
    }

    /// @inheritdoc IToll
    /// @custom:invariant Only contains tolled addresses.
    ///                     ∀x ∊ tolled(): _tolled[x]
    /// @custom:invariant Contains all tolled addresses.
    ///                     ∀x ∊ Address: _tolled[x] == 1 → x ∊ tolled()
    function tolled() public view returns (address[] memory) {
        // Initiate array with upper limit length.
        address[] memory budsList = new address[](_budsTouched.length);

        // Iterate through all possible tolled addresses.
        uint ctr;
        for (uint i; i < budsList.length; i++) {
            // Add address only if still tolled.
            if (_buds[_budsTouched[i]] == 1) {
                budsList[ctr++] = _budsTouched[i];
            }
        }

        // Set length of array to number of tolled addresses actually included.
        assembly ("memory-safe") {
            mstore(budsList, ctr)
        }

        return budsList;
    }

    /// @inheritdoc IToll
    function bud(address who) public view returns (uint) {
        return _buds[who];
    }
}

// File: src/IChainlink.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.16;

/// @notice Copy-modified from 
///         https://github.com/chronicleprotocol/aggor/blob/master/src/interfaces/_external/IChainlinkAggregatorV3.sol
///         Supports deprecated interfaces.

interface IChainlink {
    /// @notice Get the number of decimals present in the response value.
    function decimals() external view returns (uint8);

    /// @notice Get the full information for the most recent round including
    ///         the answer and update timestamps.
    function latestRoundData()
        external
        view
        returns (
            uint80 roundId,
            int answer,
            uint startedAt,
            uint updatedAt,
            uint80 answeredInRound
        );

    /// @dev This interface is deprecated, you should not use it
    function latestAnswer() external view returns (int);
}

// File: lib/chronicle-std/src/auth/IAuth.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.16;

interface IAuth {
    /// @notice Thrown by protected function if caller not auth'ed.
    /// @param caller The caller's address.
    error NotAuthorized(address caller);

    /// @notice Emitted when auth granted to address.
    /// @param caller The caller's address.
    /// @param who The address auth got granted to.
    event AuthGranted(address indexed caller, address indexed who);

    /// @notice Emitted when auth renounced from address.
    /// @param caller The caller's address.
    /// @param who The address auth got renounced from.
    event AuthRenounced(address indexed caller, address indexed who);

    /// @notice Grants address `who` auth.
    /// @dev Only callable by auth'ed address.
    /// @param who The address to grant auth.
    function rely(address who) external;

    /// @notice Renounces address `who`'s auth.
    /// @dev Only callable by auth'ed address.
    /// @param who The address to renounce auth.
    function deny(address who) external;

    /// @notice Returns whether address `who` is auth'ed.
    /// @param who The address to check.
    /// @return True if `who` is auth'ed, false otherwise.
    function authed(address who) external view returns (bool);

    /// @notice Returns full list of addresses granted auth.
    /// @dev May contain duplicates.
    /// @return List of addresses granted auth.
    function authed() external view returns (address[] memory);

    /// @notice Returns whether address `who` is auth'ed.
    /// @custom:deprecated Use `authed(address)(bool)` instead.
    /// @param who The address to check.
    /// @return 1 if `who` is auth'ed, 0 otherwise.
    function wards(address who) external view returns (uint);
}

// File: lib/chronicle-std/src/toll/IToll.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.16;

interface IToll {
    /// @notice Thrown by protected function if caller not tolled.
    /// @param caller The caller's address.
    error NotTolled(address caller);

    /// @notice Emitted when toll granted to address.
    /// @param caller The caller's address.
    /// @param who The address toll got granted to.
    event TollGranted(address indexed caller, address indexed who);

    /// @notice Emitted when toll renounced from address.
    /// @param caller The caller's address.
    /// @param who The address toll got renounced from.
    event TollRenounced(address indexed caller, address indexed who);

    /// @notice Grants address `who` toll.
    /// @dev Only callable by auth'ed address.
    /// @param who The address to grant toll.
    function kiss(address who) external;

    /// @notice Renounces address `who`'s toll.
    /// @dev Only callable by auth'ed address.
    /// @param who The address to renounce toll.
    function diss(address who) external;

    /// @notice Returns whether address `who` is tolled.
    /// @param who The address to check.
    /// @return True if `who` is tolled, false otherwise.
    function tolled(address who) external view returns (bool);

    /// @notice Returns full list of addresses tolled.
    /// @dev May contain duplicates.
    /// @return List of addresses tolled.
    function tolled() external view returns (address[] memory);

    /// @notice Returns whether address `who` is tolled.
    /// @custom:deprecated Use `tolled(address)(bool)` instead.
    /// @param who The address to check.
    /// @return 1 if `who` is tolled, 0 otherwise.
    function bud(address who) external view returns (uint);
}