// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.4 <0.9.0;

import '@defi-wonderland/isolmate/src/interfaces/tokens/IERC20.sol';

import '../IPoolManagerFactory.sol';
import '../periphery/IPriceOracleCorrections.sol';

/**
  @title PriceOracle contract
  @notice This contract allows you to get the price of different assets through WETH pools
 */
interface IPriceOracle is IPriceOracleCorrections {
  /*///////////////////////////////////////////////////////////////
                              STRUCTS
  //////////////////////////////////////////////////////////////*/

  /**
    @notice A quote saved in a particular timestamp to use as cache
    @param  quote The quote given from tokenA to tokenB
    @param  timestamp The timestamp for when the cache was saved
   */
  struct QuoteCache {
    uint256 quote;
    uint256 timestamp; // TODO not sure if it's more gas efficient to lower the uint type for this
  }

  /*///////////////////////////////////////////////////////////////
                              ERRORS
  //////////////////////////////////////////////////////////////*/

  /**
    @notice Thrown when base amount overflows uint128
   */
  error PriceOracle_BaseAmountOverflow();

  /**
    @notice Thrown when volatility in period is higher than accepted
   */
  error PriceOracle_ExceededVolatility();

  /*///////////////////////////////////////////////////////////////
                            VARIABLES
  //////////////////////////////////////////////////////////////*/

  /**
    @notice Returns the WETH token
    @return _weth The WETH token
   */
  function WETH() external view returns (IERC20 _weth);

  /**
    @notice Returns the volatility precision
    @return _volatilityPrecision The volatility precision
   */
  function VOLATILITY_PRECISION() external view returns (uint256 _volatilityPrecision);

  /**
    @notice Returns the pool manager factory
    @return _poolManagerFactory The pool manager factory
   */
  function POOL_MANAGER_FACTORY() external view returns (IPoolManagerFactory _poolManagerFactory);

  /*///////////////////////////////////////////////////////////////
                              LOGIC
  //////////////////////////////////////////////////////////////*/

  /**
    @notice Returns true if a pair is supported on the oracle
    @param  _tokenA The TokenA for the pair
    @param  _tokenB The TokenB for the pair
    @return _isSupported True if the pair is supported on the oracle
   */
  function isPairSupported(IERC20 _tokenA, IERC20 _tokenB) external view returns (bool _isSupported);

  /**
    @notice Returns the spot price of a given amount of tokenA quoted in tokenB
    @dev    _baseAmount should not be greater than uint128.max
    @param  _baseAmount The amount of tokenA to quote
    @param  _tokenA The base token
    @param  _tokenB The quote token
    @return _quoteAmount The quoted amount of tokenA in tokenB
   */
  function quoteSpot(
    uint256 _baseAmount,
    IERC20 _tokenA,
    IERC20 _tokenB
  ) external view returns (uint256 _quoteAmount);

  /**
    @notice Returns the price of a given amount of tokenA quoted in tokenB using the cache if available
    @dev    _baseAmount should not be greater than uint128.max
    @param  _baseAmount The amount of tokenA to quote
    @param  _tokenA Token to quote in tokenB
    @param  _tokenB The quote token
    @param  _period The period to quote
    @param  _cacheExpiry The max time the cache is valid for use
    @return _quoteAmount The quoted amount of tokenA in tokenB
   */
  function quotePeriodCache(
    uint256 _baseAmount,
    IERC20 _tokenA,
    IERC20 _tokenB,
    uint32 _period,
    uint24 _cacheExpiry
  ) external returns (uint256 _quoteAmount);

  /**
    @notice Returns the spot price of a given amount of tokenA quoted in tokenB reverting if it exceeds expected volatility
    @dev    _baseAmount shouldn't be greater than uint128.max
    @dev    check VOLATILITY_PRECISION for calculating the expected volatility
    @param  _baseAmount The amount of tokenA to quote
    @param  _tokenA Token to quote in tokenB
    @param  _tokenB The quote token
    @param  _period The period to quote
    @param  _volatility The max volatility
    @param  _cacheExpiry The max time the cache is valid for use
    @return _spotAmount The quoted amount of tokenA in tokenB
   */
  function quoteSpotPeriodProtectedVolatilityCache(
    uint256 _baseAmount,
    IERC20 _tokenA,
    IERC20 _tokenB,
    uint32 _period,
    uint256 _volatility,
    uint24 _cacheExpiry
  ) external returns (uint256 _spotAmount);
}