// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.27;

/// @title ILSP7NonTransferable
/// @dev Interface for a non-transferable LSP7 token, enabling control over transferability, lock periods, and allowlist exemptions.
interface ILSP7NonTransferable {
    /// @dev Emitted when the transfer lock period is updated.
    /// @param start The new start timestamp of the transfer lock period.
    /// @param end The new end timestamp of the transfer lock period.
    event TransferLockPeriodChanged(uint256 indexed start, uint256 indexed end);

    /// @notice The start timestamp of the transfer lock period, at which point the token becomes non-transferable.
    function transferLockStart() external view returns (uint256);

    /// @notice The end timestamp of the transfer lock period, at which point the token becomes transferable again.
    function transferLockEnd() external view returns (uint256);

    /// @notice Returns whether the transfer lock feature is still enabled.
    /// @dev When this returns `false`, the token has been permanently made transferable and the lock period can no longer be updated.
    function transferLockEnabled() external view returns (bool);

    /// @notice Checks if the token is currently transferable.
    /// @dev Returns true if the token is currently transferable. When `transferLockEnabled` is true, this is derived from the configured lock period. When `transferLockEnabled` is false, this always returns true. Note that transfers from allowlisted addresses and burning (transfers to address(0)) is always allowed, regardless of transferability status.
    /// @return A `true` or `false` boolean indicating if the token is transferable or not.
    function isTransferable() external view returns (bool);

    /// @notice Removes all transfer lock periods, enabling token transfers for non-allowlisted addresses.
    /// @dev Can only be called by the contract owner. Permanently disables the transfer lock feature, sets both lock periods to 0, and prevents any future lock period updates.
    /// @custom:emits {TransferLockPeriodChanged} event.
    function makeTransferable() external;

    /// @notice Updates the transfer lock period with new start and end timestamps.
    /// - When `transferLockStart` is 0 and `transferLockEnd` is set to a non-zero value, it means no start time is set. The token is non-transferable immediately until `transferLockEnd`.
    /// - When `transferLockStart` is set to a value and `transferLockEnd` is 0, it means the tokens becomes non-transferable at a certain point in time and indefinitely (no end time).
    ///
    /// - To make the token always non-transferable, set `transferLockStart` to 0 and `transferLockEnd` to type(uint256).max.
    /// - To disable completely the non-transferable feature (= make the token always transferable), set both `transferLockStart` and `transferLockEnd` to 0.
    ///
    /// @dev Can only be called by the contract owner. Reverts once {makeTransferable} has been called.
    ///
    /// @custom:emits {TransferLockPeriodChanged} event.
    /// @param newTransferLockStart The new start timestamp for the transfer lock period.
    /// @param newTransferLockEnd The new end timestamp for the transfer lock period.
    function updateTransferLockPeriod(
        uint256 newTransferLockStart,
        uint256 newTransferLockEnd
    ) external;
}