// SPDX-License-Identifier: Apache-2.0
pragma solidity 0.8.2;

interface IPolicy {

    // Events
    event LogMetadataCreated(
        address owner,
        bytes32 processId,
        uint256 productId, 
        PolicyFlowState state
    );

    event LogMetadataStateChanged(
        bytes32 processId, 
        PolicyFlowState state
    );

    event LogApplicationCreated(
        bytes32 processId, 
        uint256 premiumAmount, 
        uint256 sumInsuredAmount
    );

    event LogApplicationRevoked(bytes32 processId);
    event LogApplicationUnderwritten(bytes32 processId);
    event LogApplicationDeclined(bytes32 processId);

    event LogPolicyCreated(bytes32 processId);
    event LogPolicyExpired(bytes32 processId);
    event LogPolicyClosed(bytes32 processId);

    event LogPremiumCollected(bytes32 processId, uint256 amount);
    
    event LogApplicationSumInsuredAdjusted(bytes32 processId, uint256 sumInsuredAmountOld, uint256 sumInsuredAmount);
    event LogApplicationPremiumAdjusted(bytes32 processId, uint256 premiumAmountOld, uint256 premiumAmount);
    event LogPolicyPremiumAdjusted(bytes32 processId, uint256 premiumExpectedAmountOld, uint256 premiumExpectedAmount);

    event LogClaimCreated(bytes32 processId, uint256 claimId, uint256 claimAmount);
    event LogClaimConfirmed(bytes32 processId, uint256 claimId, uint256 confirmedAmount);
    event LogClaimDeclined(bytes32 processId, uint256 claimId);
    event LogClaimClosed(bytes32 processId, uint256 claimId);

    event LogPayoutCreated(
        bytes32 processId,
        uint256 claimId,
        uint256 payoutId,
        uint256 amount
    );

    event LogPayoutProcessed(
        bytes32 processId, 
        uint256 payoutId
    );

    // States
    enum PolicyFlowState {Started, Active, Finished}
    enum ApplicationState {Applied, Revoked, Underwritten, Declined}
    enum PolicyState {Active, Expired, Closed}
    enum ClaimState {Applied, Confirmed, Declined, Closed}
    enum PayoutState {Expected, PaidOut}

    // Objects
    struct Metadata {
        address owner;
        uint256 productId;
        PolicyFlowState state;
        bytes data;
        uint256 createdAt;
        uint256 updatedAt;
    }

    struct Application {
        ApplicationState state;
        uint256 premiumAmount;
        uint256 sumInsuredAmount;
        bytes data; 
        uint256 createdAt;
        uint256 updatedAt;
    }

    struct Policy {
        PolicyState state;
        uint256 premiumExpectedAmount;
        uint256 premiumPaidAmount;
        uint256 claimsCount;
        uint256 openClaimsCount;
        uint256 payoutMaxAmount;
        uint256 payoutAmount;
        uint256 createdAt;
        uint256 updatedAt;
    }

    struct Claim {
        ClaimState state;
        uint256 claimAmount;
        uint256 paidAmount;
        bytes data;
        uint256 createdAt;
        uint256 updatedAt;
    }

    struct Payout {
        uint256 claimId;
        PayoutState state;
        uint256 amount;
        bytes data;
        uint256 createdAt;
        uint256 updatedAt;
    }

    function createPolicyFlow(
        address owner,
        uint256 productId, 
        bytes calldata data
    ) external returns(bytes32 processId);

    function createApplication(
        bytes32 processId, 
        uint256 premiumAmount,
        uint256 sumInsuredAmount,
        bytes calldata data
    ) external;

    function revokeApplication(bytes32 processId) external;
    function underwriteApplication(bytes32 processId) external;
    function declineApplication(bytes32 processId) external;

    function collectPremium(bytes32 processId, uint256 amount) external;

    function adjustPremiumSumInsured(
        bytes32 processId, 
        uint256 expectedPremiumAmount,
        uint256 sumInsuredAmount
    ) external;

    function createPolicy(bytes32 processId) external;
    function expirePolicy(bytes32 processId) external;
    function closePolicy(bytes32 processId) external;

    function createClaim(
        bytes32 processId, 
        uint256 claimAmount, 
        bytes calldata data
    ) external returns (uint256 claimId);

    function confirmClaim(
        bytes32 processId, 
        uint256 claimId, 
        uint256 confirmedAmount
    ) external;

    function declineClaim(bytes32 processId, uint256 claimId) external;
    function closeClaim(bytes32 processId, uint256 claimId) external;

    function createPayout(
        bytes32 processId,
        uint256 claimId,
        uint256 payoutAmount,
        bytes calldata data
    ) external returns (uint256 payoutId);

    function processPayout(
        bytes32 processId,
        uint256 payoutId
    ) external;
}