// SPDX-License-Identifier: MIT

pragma solidity =0.8.18;

/**
 * @title SOMA Swap ERC20 Contract.
 * @author SOMA.finance
 * @notice Interface of the Soma Swap ERC20 contract.
 */
interface ISomaSwapERC20 {
    /**
     * @notice Emitted when the ``owner``'s tokens are approved for spending by `spender`.
     * @param owner The address of the owner.
     * @param spender The address of the spender.
     * @param value The amount of tokens that approved for spending by `spender`.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @notice Emitted when `value` tokens are sent from `from` to `to`.
     * @param from The address that the tokens are being transferred from.
     * @param to The address receiving the tokens.
     * @param value The amount of tokens transferred.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @notice The name of the token.
     */
    function name() external pure returns (string memory);

    /**
     * @notice The symbol of the token.
     */
    function symbol() external pure returns (string memory);

    /**
     * @notice The decimals of the token.
     */
    function decimals() external pure returns (uint8);

    /**
     * @notice The total supply of the token.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @notice Returns the token balance of a holder.
     * @param owner The address of the token holder.
     * @return The balance of the holder.
     */
    function balanceOf(address owner) external view returns (uint256);

    /**
     * @notice Returns the remaining number of tokens that `spender` will be allowed
     * to spend on behalf of `owner` through transferFrom.
     * @param owner The address of the token holder.
     * @param spender The caller of the function.
     * @return The amount of tokens approved for spending by the `spender`.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @notice Approves `value` tokens to be spent by `spender`.
     * @param spender The caller of the function.
     * @param value The number of tokens to be approved for spending.
     * @custom:emits Approval
     * @return Boolean indicating if the transaction was successful.
     */
    function approve(address spender, uint256 value) external returns (bool);

    /**
     * @notice Transfers `value` tokens to `to`.
     * @param to The recipient of the tokens.
     * @param value The number of tokens to be transferred.
     * @custom:emits Transfer
     * @return Boolean value indicating if the operation was successful.
     */
    function transfer(address to, uint256 value) external returns (bool);

    /**
     * @notice Transfers `value` tokens from `from` to `to` using the allowance mechanism.
     * @param from The address that the tokens will be transferred from.
     * @param to The address that the tokens will be transferred to.
     * @param value The amount of tokens to be transferred.
     * @return Boolean indicating if the transaction was successful.
     */
    function transferFrom(address from, address to, uint256 value) external returns (bool);

    /**
     * @notice Returns the domain separator of the token which prevents replay attacks from other domains.
     */
    function DOMAIN_SEPARATOR() external view returns (bytes32);

    /**
     * @notice Returns the permit typehash of the token.
     */
    function PERMIT_TYPEHASH() external pure returns (bytes32);

    /**
     * @notice Returns the permit typehash of the token.
     * @param owner The address of the owner of the tokens.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @notice Modifies ``spender``'s allowance via signatures.
     * @param owner The holder of the tokens.
     * @param spender The caller of the method.
     * @param value The number of tokens being moved.
     * @param v The v component of the permit signature.
     * @param r The r component of the permit signature.
     * @param s The s component of the permit signature.
     */
    function permit(address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s)
        external;
}