// Sources flattened with hardhat v2.10.1 https://hardhat.org

// File @openzeppelin/contracts/utils/Context.sol@v4.7.2

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @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 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) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}


// File @openzeppelin/contracts/access/Ownable.sol@v4.7.2


// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

/**
 * @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.
 */
abstract 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() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        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 {
        _transferOwnership(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");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}


// File contracts/interfaces/IPriceOracleGetter.sol


pragma solidity ^0.8.0;

interface IPriceOracleGetter {
  function getAssetPrice(address asset) external view returns (uint256);
}


// File contracts/interfaces/IPriceGetter.sol


pragma solidity ^0.8.0;

interface IPriceGetter {
  function getPrice() external view returns (uint256 price);
}


// File contracts/FallbackOracle.sol


pragma solidity ^0.8.0;



contract FallbackOracle is IPriceOracleGetter, Ownable {
  mapping (address => IPriceGetter) private assetToPriceGetter;

  constructor(address[] memory assets, address[] memory getters) {
    _setAssetPriceGetterBatch(assets, getters);
  }

  function getAssetPrice(address asset) external view returns (uint256) {
    require(address(assetToPriceGetter[asset]) != address(0), '!exists');
    return assetToPriceGetter[asset].getPrice();
  }

  function setAssetPriceGetter(address asset, address getter) external onlyOwner {
    assetToPriceGetter[asset] = IPriceGetter(getter);
  }

  function setAssetPriceGetterBatch(address[] calldata assets, address[] calldata getters) external onlyOwner {
    _setAssetPriceGetterBatch(assets, getters);
  }

  function _setAssetPriceGetterBatch(address[] memory assets, address[] memory getters) internal {
    require(assets.length == getters.length, '!equal');
    for (uint i = 0; i < assets.length; i++) {
      assetToPriceGetter[assets[i]] = IPriceGetter(getters[i]);
    }
  }
}