// File: lib/VRGDAs/src/LinearVRGDA.sol



// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;

import {unsafeWadDiv} from "solmate/utils/SignedWadMath.sol";

import {VRGDA} from "./VRGDA.sol";

/// @title Linear Variable Rate Gradual Dutch Auction
/// @author transmissions11 <t11s@paradigm.xyz>
/// @author FrankieIsLost <frankie@paradigm.xyz>
/// @notice VRGDA with a linear issuance curve.
abstract contract LinearVRGDA is VRGDA {
    /*//////////////////////////////////////////////////////////////
                           PRICING PARAMETERS
    //////////////////////////////////////////////////////////////*/

    /// @dev The total number of tokens to target selling every full unit of time.
    /// @dev Represented as an 18 decimal fixed point number.
    int256 internal immutable perTimeUnit;

    /// @notice Sets pricing parameters for the VRGDA.
    /// @param _targetPrice The target price for a token if sold on pace, scaled by 1e18.
    /// @param _priceDecayPercent The percent price decays per unit of time with no sales, scaled by 1e18.
    /// @param _perTimeUnit The number of tokens to target selling in 1 full unit of time, scaled by 1e18.
    constructor(
        int256 _targetPrice,
        int256 _priceDecayPercent,
        int256 _perTimeUnit
    ) VRGDA(_targetPrice, _priceDecayPercent) {
        perTimeUnit = _perTimeUnit;
    }

    /*//////////////////////////////////////////////////////////////
                              PRICING LOGIC
    //////////////////////////////////////////////////////////////*/

    /// @dev Given a number of tokens sold, return the target time that number of tokens should be sold by.
    /// @param sold A number of tokens sold, scaled by 1e18, to get the corresponding target sale time for.
    /// @return The target time the tokens should be sold by, scaled by 1e18, where the time is
    /// relative, such that 0 means the tokens should be sold immediately when the VRGDA begins.
    function getTargetSaleTime(int256 sold) public view virtual override returns (int256) {
        return unsafeWadDiv(sold, perTimeUnit);
    }
}

// File: lib/VRGDAs/src/VRGDA.sol



// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;

import {wadExp, wadLn, wadMul, unsafeWadMul, toWadUnsafe} from "solmate/utils/SignedWadMath.sol";

/// @title Variable Rate Gradual Dutch Auction
/// @author transmissions11 <t11s@paradigm.xyz>
/// @author FrankieIsLost <frankie@paradigm.xyz>
/// @notice Sell tokens roughly according to an issuance schedule.
abstract contract VRGDA {
    /*//////////////////////////////////////////////////////////////
                            VRGDA PARAMETERS
    //////////////////////////////////////////////////////////////*/

    /// @notice Target price for a token, to be scaled according to sales pace.
    /// @dev Represented as an 18 decimal fixed point number.
    int256 public immutable targetPrice;

    /// @dev Precomputed constant that allows us to rewrite a pow() as an exp().
    /// @dev Represented as an 18 decimal fixed point number.
    int256 internal immutable decayConstant;

    /// @notice Sets target price and per time unit price decay for the VRGDA.
    /// @param _targetPrice The target price for a token if sold on pace, scaled by 1e18.
    /// @param _priceDecayPercent The percent price decays per unit of time with no sales, scaled by 1e18.
    constructor(int256 _targetPrice, int256 _priceDecayPercent) {
        targetPrice = _targetPrice;

        decayConstant = wadLn(1e18 - _priceDecayPercent);

        // The decay constant must be negative for VRGDAs to work.
        require(decayConstant < 0, "NON_NEGATIVE_DECAY_CONSTANT");
    }

    /*//////////////////////////////////////////////////////////////
                              PRICING LOGIC
    //////////////////////////////////////////////////////////////*/

    /// @notice Calculate the price of a token according to the VRGDA formula.
    /// @param timeSinceStart Time passed since the VRGDA began, scaled by 1e18.
    /// @param sold The total number of tokens that have been sold so far.
    /// @return The price of a token according to VRGDA, scaled by 1e18.
    function getVRGDAPrice(int256 timeSinceStart, uint256 sold) public view virtual returns (uint256) {
        unchecked {
            // prettier-ignore
            return uint256(wadMul(targetPrice, wadExp(unsafeWadMul(decayConstant,
                // Theoretically calling toWadUnsafe with sold can silently overflow but under
                // any reasonable circumstance it will never be large enough. We use sold + 1 as
                // the VRGDA formula's n param represents the nth token and sold is the n-1th token.
                timeSinceStart - getTargetSaleTime(toWadUnsafe(sold + 1))
            ))));
        }
    }

    /// @dev Given a number of tokens sold, return the target time that number of tokens should be sold by.
    /// @param sold A number of tokens sold, scaled by 1e18, to get the corresponding target sale time for.
    /// @return The target time the tokens should be sold by, scaled by 1e18, where the time is
    /// relative, such that 0 means the tokens should be sold immediately when the VRGDA begins.
    function getTargetSaleTime(int256 sold) public view virtual returns (int256);
}

// File: lib/solady/src/utils/Base64.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Library to encode strings in Base64.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/Base64.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/Base64.sol)
/// @author Modified from (https://github.com/Brechtpd/base64/blob/main/base64.sol) by Brecht Devos - <brecht@loopring.org>.
library Base64 {
    /// @dev Encodes `data` using the base64 encoding described in RFC 4648.
    /// See: https://datatracker.ietf.org/doc/html/rfc4648
    /// @param fileSafe  Whether to replace '+' with '-' and '/' with '_'.
    /// @param noPadding Whether to strip away the padding.
    function encode(
        bytes memory data,
        bool fileSafe,
        bool noPadding
    ) internal pure returns (string memory result) {
        assembly {
            let dataLength := mload(data)

            if dataLength {
                // Multiply by 4/3 rounded up.
                // The `shl(2, ...)` is equivalent to multiplying by 4.
                let encodedLength := shl(2, div(add(dataLength, 2), 3))

                // Set `result` to point to the start of the free memory.
                result := mload(0x40)

                // Store the table into the scratch space.
                // Offsetted by -1 byte so that the `mload` will load the character.
                // We will rewrite the free memory pointer at `0x40` later with
                // the allocated size.
                // The magic constant 0x0230 will translate "-_" + "+/".
                mstore(0x1f, "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdef")
                mstore(0x3f, sub("ghijklmnopqrstuvwxyz0123456789-_", mul(iszero(fileSafe), 0x0230)))

                // Skip the first slot, which stores the length.
                let ptr := add(result, 0x20)
                let end := add(ptr, encodedLength)

                // Run over the input, 3 bytes at a time.
                // prettier-ignore
                for {} 1 {} {
                    data := add(data, 3) // Advance 3 bytes.
                    let input := mload(data)

                    // Write 4 bytes. Optimized for fewer stack operations.
                    mstore8(    ptr    , mload(and(shr(18, input), 0x3F)))
                    mstore8(add(ptr, 1), mload(and(shr(12, input), 0x3F)))
                    mstore8(add(ptr, 2), mload(and(shr( 6, input), 0x3F)))
                    mstore8(add(ptr, 3), mload(and(        input , 0x3F)))
                    
                    ptr := add(ptr, 4) // Advance 4 bytes.
                    // prettier-ignore
                    if iszero(lt(ptr, end)) { break }
                }

                let r := mod(dataLength, 3)

                switch noPadding
                case 0 {
                    // Offset `ptr` and pad with '='. We can simply write over the end.
                    mstore8(sub(ptr, iszero(iszero(r))), 0x3d) // Pad at `ptr - 1` if `r > 0`.
                    mstore8(sub(ptr, shl(1, eq(r, 1))), 0x3d) // Pad at `ptr - 2` if `r == 1`.
                    // Write the length of the string.
                    mstore(result, encodedLength)
                }
                default {
                    // Write the length of the string.
                    mstore(result, sub(encodedLength, add(iszero(iszero(r)), eq(r, 1))))
                }

                // Allocate the memory for the string.
                // Add 31 and mask with `not(31)` to round the
                // free memory pointer up the next multiple of 32.
                mstore(0x40, and(add(end, 31), not(31)))
            }
        }
    }

    /// @dev Encodes `data` using the base64 encoding described in RFC 4648.
    /// Equivalent to `encode(data, false, false)`.
    function encode(bytes memory data) internal pure returns (string memory result) {
        result = encode(data, false, false);
    }

    /// @dev Encodes `data` using the base64 encoding described in RFC 4648.
    /// Equivalent to `encode(data, fileSafe, false)`.
    function encode(bytes memory data, bool fileSafe) internal pure returns (string memory result) {
        result = encode(data, fileSafe, false);
    }

    /// @dev Encodes base64 encoded `data`.
    ///
    /// Supports:
    /// - RFC 4648 (both standard and file-safe mode).
    /// - RFC 3501 (63: ',').
    ///
    /// Does not support:
    /// - Line breaks.
    ///
    /// Note: For performance reasons,
    /// this function will NOT revert on invalid `data` inputs.
    /// Outputs for invalid inputs will simply be undefined behaviour.
    /// It is the user's responsibility to ensure that the `data`
    /// is a valid base64 encoded string.
    function decode(string memory data) internal pure returns (bytes memory result) {
        assembly {
            let dataLength := mload(data)

            if dataLength {
                let end := add(data, dataLength)
                let decodedLength := mul(shr(2, dataLength), 3)

                switch and(dataLength, 3)
                case 0 {
                    // If padded.
                    decodedLength := sub(
                        decodedLength,
                        add(eq(and(mload(end), 0xFF), 0x3d), eq(and(mload(end), 0xFFFF), 0x3d3d))
                    )
                }
                default {
                    // If non-padded.
                    decodedLength := add(decodedLength, sub(and(dataLength, 3), 1))
                }

                result := mload(0x40)

                // Write the length of the string.
                mstore(result, decodedLength)

                // Skip the first slot, which stores the length.
                let ptr := add(result, 0x20)

                // Load the table into the scratch space.
                // Constants are optimized for smaller bytecode with zero gas overhead.
                // `m` also doubles as the mask of the upper 6 bits.
                let m := 0xfc000000fc00686c7074787c8084888c9094989ca0a4a8acb0b4b8bcc0c4c8cc
                mstore(0x5b, m)
                mstore(0x3b, 0x04080c1014181c2024282c3034383c4044484c5054585c6064)
                mstore(0x1a, 0xf8fcf800fcd0d4d8dce0e4e8ecf0f4)

                // prettier-ignore
                for {} 1 {} {
                    // Read 4 bytes.
                    data := add(data, 4)
                    let input := mload(data)

                    // Write 3 bytes.
                    mstore(ptr, or(
                        and(m, mload(byte(28, input))),
                        shr(6, or(
                            and(m, mload(byte(29, input))),
                            shr(6, or(
                                and(m, mload(byte(30, input))),
                                shr(6, mload(byte(31, input)))
                            ))
                        ))
                    ))

                    ptr := add(ptr, 3)
                    
                    // prettier-ignore
                    if iszero(lt(data, end)) { break }
                }

                // Allocate the memory for the string.
                // Add 32 + 31 and mask with `not(31)` to round the
                // free memory pointer up the next multiple of 32.
                mstore(0x40, and(add(add(result, decodedLength), 63), not(31)))

                // Restore the zero slot.
                mstore(0x60, 0)
            }
        }
    }
}

// File: lib/solmate/src/auth/Owned.sol



// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

/// @notice Simple single owner authorization mixin.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/auth/Owned.sol)
abstract contract Owned {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event OwnershipTransferred(address indexed user, address indexed newOwner);

    /*//////////////////////////////////////////////////////////////
                            OWNERSHIP STORAGE
    //////////////////////////////////////////////////////////////*/

    address public owner;

    modifier onlyOwner() virtual {
        require(msg.sender == owner, "UNAUTHORIZED");

        _;
    }

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

    constructor(address _owner) {
        owner = _owner;

        emit OwnershipTransferred(address(0), _owner);
    }

    /*//////////////////////////////////////////////////////////////
                             OWNERSHIP LOGIC
    //////////////////////////////////////////////////////////////*/

    function transferOwnership(address newOwner) public virtual onlyOwner {
        owner = newOwner;

        emit OwnershipTransferred(msg.sender, newOwner);
    }
}

// File: lib/solmate/src/tokens/ERC20.sol



// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

/// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
/// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
abstract contract ERC20 {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event Transfer(address indexed from, address indexed to, uint256 amount);

    event Approval(address indexed owner, address indexed spender, uint256 amount);

    /*//////////////////////////////////////////////////////////////
                            METADATA STORAGE
    //////////////////////////////////////////////////////////////*/

    string public name;

    string public symbol;

    uint8 public immutable decimals;

    /*//////////////////////////////////////////////////////////////
                              ERC20 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 public totalSupply;

    mapping(address => uint256) public balanceOf;

    mapping(address => mapping(address => uint256)) public allowance;

    /*//////////////////////////////////////////////////////////////
                            EIP-2612 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 internal immutable INITIAL_CHAIN_ID;

    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;

    mapping(address => uint256) public nonces;

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

    constructor(
        string memory _name,
        string memory _symbol,
        uint8 _decimals
    ) {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;

        INITIAL_CHAIN_ID = block.chainid;
        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
    }

    /*//////////////////////////////////////////////////////////////
                               ERC20 LOGIC
    //////////////////////////////////////////////////////////////*/

    function approve(address spender, uint256 amount) public virtual returns (bool) {
        allowance[msg.sender][spender] = amount;

        emit Approval(msg.sender, spender, amount);

        return true;
    }

    function transfer(address to, uint256 amount) public virtual returns (bool) {
        balanceOf[msg.sender] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(msg.sender, to, amount);

        return true;
    }

    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual returns (bool) {
        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.

        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;

        balanceOf[from] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(from, to, amount);

        return true;
    }

    /*//////////////////////////////////////////////////////////////
                             EIP-2612 LOGIC
    //////////////////////////////////////////////////////////////*/

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");

        // Unchecked because the only math done is incrementing
        // the owner's nonce which cannot realistically overflow.
        unchecked {
            address recoveredAddress = ecrecover(
                keccak256(
                    abi.encodePacked(
                        "\x19\x01",
                        DOMAIN_SEPARATOR(),
                        keccak256(
                            abi.encode(
                                keccak256(
                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                ),
                                owner,
                                spender,
                                value,
                                nonces[owner]++,
                                deadline
                            )
                        )
                    )
                ),
                v,
                r,
                s
            );

            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");

            allowance[recoveredAddress][spender] = value;
        }

        emit Approval(owner, spender, value);
    }

    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
    }

    function computeDomainSeparator() internal view virtual returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                    keccak256(bytes(name)),
                    keccak256("1"),
                    block.chainid,
                    address(this)
                )
            );
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/

    function _mint(address to, uint256 amount) internal virtual {
        totalSupply += amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(address(0), to, amount);
    }

    function _burn(address from, uint256 amount) internal virtual {
        balanceOf[from] -= amount;

        // Cannot underflow because a user's balance
        // will never be larger than the total supply.
        unchecked {
            totalSupply -= amount;
        }

        emit Transfer(from, address(0), amount);
    }
}

// File: lib/solmate/src/tokens/ERC721.sol



// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

/// @notice Modern, minimalist, and gas efficient ERC-721 implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
abstract contract ERC721 {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event Transfer(address indexed from, address indexed to, uint256 indexed id);

    event Approval(address indexed owner, address indexed spender, uint256 indexed id);

    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    /*//////////////////////////////////////////////////////////////
                         METADATA STORAGE/LOGIC
    //////////////////////////////////////////////////////////////*/

    string public name;

    string public symbol;

    function tokenURI(uint256 id) public view virtual returns (string memory);

    /*//////////////////////////////////////////////////////////////
                      ERC721 BALANCE/OWNER STORAGE
    //////////////////////////////////////////////////////////////*/

    mapping(uint256 => address) internal _ownerOf;

    mapping(address => uint256) internal _balanceOf;

    function ownerOf(uint256 id) public view virtual returns (address owner) {
        require((owner = _ownerOf[id]) != address(0), "NOT_MINTED");
    }

    function balanceOf(address owner) public view virtual returns (uint256) {
        require(owner != address(0), "ZERO_ADDRESS");

        return _balanceOf[owner];
    }

    /*//////////////////////////////////////////////////////////////
                         ERC721 APPROVAL STORAGE
    //////////////////////////////////////////////////////////////*/

    mapping(uint256 => address) public getApproved;

    mapping(address => mapping(address => bool)) public isApprovedForAll;

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

    constructor(string memory _name, string memory _symbol) {
        name = _name;
        symbol = _symbol;
    }

    /*//////////////////////////////////////////////////////////////
                              ERC721 LOGIC
    //////////////////////////////////////////////////////////////*/

    function approve(address spender, uint256 id) public virtual {
        address owner = _ownerOf[id];

        require(msg.sender == owner || isApprovedForAll[owner][msg.sender], "NOT_AUTHORIZED");

        getApproved[id] = spender;

        emit Approval(owner, spender, id);
    }

    function setApprovalForAll(address operator, bool approved) public virtual {
        isApprovedForAll[msg.sender][operator] = approved;

        emit ApprovalForAll(msg.sender, operator, approved);
    }

    function transferFrom(
        address from,
        address to,
        uint256 id
    ) public virtual {
        require(from == _ownerOf[id], "WRONG_FROM");

        require(to != address(0), "INVALID_RECIPIENT");

        require(
            msg.sender == from || isApprovedForAll[from][msg.sender] || msg.sender == getApproved[id],
            "NOT_AUTHORIZED"
        );

        // Underflow of the sender's balance is impossible because we check for
        // ownership above and the recipient's balance can't realistically overflow.
        unchecked {
            _balanceOf[from]--;

            _balanceOf[to]++;
        }

        _ownerOf[id] = to;

        delete getApproved[id];

        emit Transfer(from, to, id);
    }

    function safeTransferFrom(
        address from,
        address to,
        uint256 id
    ) public virtual {
        transferFrom(from, to, id);

        require(
            to.code.length == 0 ||
                ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, "") ==
                ERC721TokenReceiver.onERC721Received.selector,
            "UNSAFE_RECIPIENT"
        );
    }

    function safeTransferFrom(
        address from,
        address to,
        uint256 id,
        bytes calldata data
    ) public virtual {
        transferFrom(from, to, id);

        require(
            to.code.length == 0 ||
                ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, data) ==
                ERC721TokenReceiver.onERC721Received.selector,
            "UNSAFE_RECIPIENT"
        );
    }

    /*//////////////////////////////////////////////////////////////
                              ERC165 LOGIC
    //////////////////////////////////////////////////////////////*/

    function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
        return
            interfaceId == 0x01ffc9a7 || // ERC165 Interface ID for ERC165
            interfaceId == 0x80ac58cd || // ERC165 Interface ID for ERC721
            interfaceId == 0x5b5e139f; // ERC165 Interface ID for ERC721Metadata
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/

    function _mint(address to, uint256 id) internal virtual {
        require(to != address(0), "INVALID_RECIPIENT");

        require(_ownerOf[id] == address(0), "ALREADY_MINTED");

        // Counter overflow is incredibly unrealistic.
        unchecked {
            _balanceOf[to]++;
        }

        _ownerOf[id] = to;

        emit Transfer(address(0), to, id);
    }

    function _burn(uint256 id) internal virtual {
        address owner = _ownerOf[id];

        require(owner != address(0), "NOT_MINTED");

        // Ownership check above ensures no underflow.
        unchecked {
            _balanceOf[owner]--;
        }

        delete _ownerOf[id];

        delete getApproved[id];

        emit Transfer(owner, address(0), id);
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL SAFE MINT LOGIC
    //////////////////////////////////////////////////////////////*/

    function _safeMint(address to, uint256 id) internal virtual {
        _mint(to, id);

        require(
            to.code.length == 0 ||
                ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, "") ==
                ERC721TokenReceiver.onERC721Received.selector,
            "UNSAFE_RECIPIENT"
        );
    }

    function _safeMint(
        address to,
        uint256 id,
        bytes memory data
    ) internal virtual {
        _mint(to, id);

        require(
            to.code.length == 0 ||
                ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, data) ==
                ERC721TokenReceiver.onERC721Received.selector,
            "UNSAFE_RECIPIENT"
        );
    }
}

/// @notice A generic interface for a contract which properly accepts ERC721 tokens.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
abstract contract ERC721TokenReceiver {
    function onERC721Received(
        address,
        address,
        uint256,
        bytes calldata
    ) external virtual returns (bytes4) {
        return ERC721TokenReceiver.onERC721Received.selector;
    }
}

// File: lib/solmate/src/utils/LibString.sol



// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;

/// @notice Efficient library for creating string representations of integers.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/LibString.sol)
/// @author Modified from Solady (https://github.com/Vectorized/solady/blob/main/src/utils/LibString.sol)
library LibString {
    function toString(uint256 value) internal pure returns (string memory str) {
        assembly {
            // The maximum value of a uint256 contains 78 digits (1 byte per digit), but we allocate 160 bytes
            // to keep the free memory pointer word aligned. We'll need 1 word for the length, 1 word for the
            // trailing zeros padding, and 3 other words for a max of 78 digits. In total: 5 * 32 = 160 bytes.
            let newFreeMemoryPointer := add(mload(0x40), 160)

            // Update the free memory pointer to avoid overriding our string.
            mstore(0x40, newFreeMemoryPointer)

            // Assign str to the end of the zone of newly allocated memory.
            str := sub(newFreeMemoryPointer, 32)

            // Clean the last word of memory it may not be overwritten.
            mstore(str, 0)

            // Cache the end of the memory to calculate the length later.
            let end := str

            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            // prettier-ignore
            for { let temp := value } 1 {} {
                // Move the pointer 1 byte to the left.
                str := sub(str, 1)

                // Write the character to the pointer.
                // The ASCII index of the '0' character is 48.
                mstore8(str, add(48, mod(temp, 10)))

                // Keep dividing temp until zero.
                temp := div(temp, 10)

                 // prettier-ignore
                if iszero(temp) { break }
            }

            // Compute and cache the final total length of the string.
            let length := sub(end, str)

            // Move the pointer 32 bytes leftwards to make room for the length.
            str := sub(str, 32)

            // Store the string's length at the start of memory allocated for our string.
            mstore(str, length)
        }
    }
}

// File: lib/solmate/src/utils/SafeTransferLib.sol



// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

import {ERC20} from "../tokens/ERC20.sol";

/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
/// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
/// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
library SafeTransferLib {
    /*//////////////////////////////////////////////////////////////
                             ETH OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferETH(address to, uint256 amount) internal {
        bool success;

        assembly {
            // Transfer the ETH and store if it succeeded or not.
            success := call(gas(), to, amount, 0, 0, 0, 0)
        }

        require(success, "ETH_TRANSFER_FAILED");
    }

    /*//////////////////////////////////////////////////////////////
                            ERC20 OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferFrom(
        ERC20 token,
        address from,
        address to,
        uint256 amount
    ) internal {
        bool success;

        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), from) // Append the "from" argument.
            mstore(add(freeMemoryPointer, 36), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)
            )
        }

        require(success, "TRANSFER_FROM_FAILED");
    }

    function safeTransfer(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;

        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "TRANSFER_FAILED");
    }

    function safeApprove(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;

        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "APPROVE_FAILED");
    }
}

// File: lib/solmate/src/utils/SignedWadMath.sol



// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;

/// @notice Signed 18 decimal fixed point (wad) arithmetic library.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SignedWadMath.sol)
/// @author Modified from Remco Bloemen (https://xn--2-umb.com/22/exp-ln/index.html)

/// @dev Will not revert on overflow, only use where overflow is not possible.
function toWadUnsafe(uint256 x) pure returns (int256 r) {
    assembly {
        // Multiply x by 1e18.
        r := mul(x, 1000000000000000000)
    }
}

/// @dev Takes an integer amount of seconds and converts it to a wad amount of days.
/// @dev Will not revert on overflow, only use where overflow is not possible.
/// @dev Not meant for negative second amounts, it assumes x is positive.
function toDaysWadUnsafe(uint256 x) pure returns (int256 r) {
    assembly {
        // Multiply x by 1e18 and then divide it by 86400.
        r := div(mul(x, 1000000000000000000), 86400)
    }
}

/// @dev Takes a wad amount of days and converts it to an integer amount of seconds.
/// @dev Will not revert on overflow, only use where overflow is not possible.
/// @dev Not meant for negative day amounts, it assumes x is positive.
function fromDaysWadUnsafe(int256 x) pure returns (uint256 r) {
    assembly {
        // Multiply x by 86400 and then divide it by 1e18.
        r := div(mul(x, 86400), 1000000000000000000)
    }
}

/// @dev Will not revert on overflow, only use where overflow is not possible.
function unsafeWadMul(int256 x, int256 y) pure returns (int256 r) {
    assembly {
        // Multiply x by y and divide by 1e18.
        r := sdiv(mul(x, y), 1000000000000000000)
    }
}

/// @dev Will return 0 instead of reverting if y is zero and will
/// not revert on overflow, only use where overflow is not possible.
function unsafeWadDiv(int256 x, int256 y) pure returns (int256 r) {
    assembly {
        // Multiply x by 1e18 and divide it by y.
        r := sdiv(mul(x, 1000000000000000000), y)
    }
}

function wadMul(int256 x, int256 y) pure returns (int256 r) {
    assembly {
        // Store x * y in r for now.
        r := mul(x, y)

        // Equivalent to require(x == 0 || (x * y) / x == y)
        if iszero(or(iszero(x), eq(sdiv(r, x), y))) {
            revert(0, 0)
        }

        // Scale the result down by 1e18.
        r := sdiv(r, 1000000000000000000)
    }
}

function wadDiv(int256 x, int256 y) pure returns (int256 r) {
    assembly {
        // Store x * 1e18 in r for now.
        r := mul(x, 1000000000000000000)

        // Equivalent to require(y != 0 && ((x * 1e18) / 1e18 == x))
        if iszero(and(iszero(iszero(y)), eq(sdiv(r, 1000000000000000000), x))) {
            revert(0, 0)
        }

        // Divide r by y.
        r := sdiv(r, y)
    }
}

function wadExp(int256 x) pure returns (int256 r) {
    unchecked {
        // When the result is < 0.5 we return zero. This happens when
        // x <= floor(log(0.5e18) * 1e18) ~ -42e18
        if (x <= -42139678854452767551) return 0;

        // When the result is > (2**255 - 1) / 1e18 we can not represent it as an
        // int. This happens when x >= floor(log((2**255 - 1) / 1e18) * 1e18) ~ 135.
        if (x >= 135305999368893231589) revert("EXP_OVERFLOW");

        // x is now in the range (-42, 136) * 1e18. Convert to (-42, 136) * 2**96
        // for more intermediate precision and a binary basis. This base conversion
        // is a multiplication by 1e18 / 2**96 = 5**18 / 2**78.
        x = (x << 78) / 5**18;

        // Reduce range of x to (-½ ln 2, ½ ln 2) * 2**96 by factoring out powers
        // of two such that exp(x) = exp(x') * 2**k, where k is an integer.
        // Solving this gives k = round(x / log(2)) and x' = x - k * log(2).
        int256 k = ((x << 96) / 54916777467707473351141471128 + 2**95) >> 96;
        x = x - k * 54916777467707473351141471128;

        // k is in the range [-61, 195].

        // Evaluate using a (6, 7)-term rational approximation.
        // p is made monic, we'll multiply by a scale factor later.
        int256 y = x + 1346386616545796478920950773328;
        y = ((y * x) >> 96) + 57155421227552351082224309758442;
        int256 p = y + x - 94201549194550492254356042504812;
        p = ((p * y) >> 96) + 28719021644029726153956944680412240;
        p = p * x + (4385272521454847904659076985693276 << 96);

        // We leave p in 2**192 basis so we don't need to scale it back up for the division.
        int256 q = x - 2855989394907223263936484059900;
        q = ((q * x) >> 96) + 50020603652535783019961831881945;
        q = ((q * x) >> 96) - 533845033583426703283633433725380;
        q = ((q * x) >> 96) + 3604857256930695427073651918091429;
        q = ((q * x) >> 96) - 14423608567350463180887372962807573;
        q = ((q * x) >> 96) + 26449188498355588339934803723976023;

        assembly {
            // Div in assembly because solidity adds a zero check despite the unchecked.
            // The q polynomial won't have zeros in the domain as all its roots are complex.
            // No scaling is necessary because p is already 2**96 too large.
            r := sdiv(p, q)
        }

        // r should be in the range (0.09, 0.25) * 2**96.

        // We now need to multiply r by:
        // * the scale factor s = ~6.031367120.
        // * the 2**k factor from the range reduction.
        // * the 1e18 / 2**96 factor for base conversion.
        // We do this all at once, with an intermediate result in 2**213
        // basis, so the final right shift is always by a positive amount.
        r = int256((uint256(r) * 3822833074963236453042738258902158003155416615667) >> uint256(195 - k));
    }
}

function wadLn(int256 x) pure returns (int256 r) {
    unchecked {
        require(x > 0, "UNDEFINED");

        // We want to convert x from 10**18 fixed point to 2**96 fixed point.
        // We do this by multiplying by 2**96 / 10**18. But since
        // ln(x * C) = ln(x) + ln(C), we can simply do nothing here
        // and add ln(2**96 / 10**18) at the end.

        assembly {
            r := shl(7, lt(0xffffffffffffffffffffffffffffffff, x))
            r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
            r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
            r := or(r, shl(4, lt(0xffff, shr(r, x))))
            r := or(r, shl(3, lt(0xff, shr(r, x))))
            r := or(r, shl(2, lt(0xf, shr(r, x))))
            r := or(r, shl(1, lt(0x3, shr(r, x))))
            r := or(r, lt(0x1, shr(r, x)))
        }

        // Reduce range of x to (1, 2) * 2**96
        // ln(2^k * x) = k * ln(2) + ln(x)
        int256 k = r - 96;
        x <<= uint256(159 - k);
        x = int256(uint256(x) >> 159);

        // Evaluate using a (8, 8)-term rational approximation.
        // p is made monic, we will multiply by a scale factor later.
        int256 p = x + 3273285459638523848632254066296;
        p = ((p * x) >> 96) + 24828157081833163892658089445524;
        p = ((p * x) >> 96) + 43456485725739037958740375743393;
        p = ((p * x) >> 96) - 11111509109440967052023855526967;
        p = ((p * x) >> 96) - 45023709667254063763336534515857;
        p = ((p * x) >> 96) - 14706773417378608786704636184526;
        p = p * x - (795164235651350426258249787498 << 96);

        // We leave p in 2**192 basis so we don't need to scale it back up for the division.
        // q is monic by convention.
        int256 q = x + 5573035233440673466300451813936;
        q = ((q * x) >> 96) + 71694874799317883764090561454958;
        q = ((q * x) >> 96) + 283447036172924575727196451306956;
        q = ((q * x) >> 96) + 401686690394027663651624208769553;
        q = ((q * x) >> 96) + 204048457590392012362485061816622;
        q = ((q * x) >> 96) + 31853899698501571402653359427138;
        q = ((q * x) >> 96) + 909429971244387300277376558375;
        assembly {
            // Div in assembly because solidity adds a zero check despite the unchecked.
            // The q polynomial is known not to have zeros in the domain.
            // No scaling required because p is already 2**96 too large.
            r := sdiv(p, q)
        }

        // r is in the range (0, 0.125) * 2**96

        // Finalization, we need to:
        // * multiply by the scale factor s = 5.549…
        // * add ln(2**96 / 10**18)
        // * add k * ln(2)
        // * multiply by 10**18 / 2**96 = 5**18 >> 78

        // mul s * 5e18 * 2**96, base is now 5**18 * 2**192
        r *= 1677202110996718588342820967067443963516166;
        // add ln(2) * k * 5e18 * 2**192
        r += 16597577552685614221487285958193947469193820559219878177908093499208371 * k;
        // add ln(2**96 / 10**18) * 5e18 * 2**192
        r += 600920179829731861736702779321621459595472258049074101567377883020018308;
        // base conversion: mul 2**18 / 2**192
        r >>= 174;
    }
}

/// @dev Will return 0 instead of reverting if y is zero.
function unsafeDiv(int256 x, int256 y) pure returns (int256 r) {
    assembly {
        // Divide x by y.
        r := sdiv(x, y)
    }
}

// File: src/Metadata.sol



// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.13;

import {LibString} from "solmate/utils/LibString.sol";
import {Base64} from "solady/utils/Base64.sol";

library Metadata {
    using LibString for uint256;

    function toImageURI(string memory cid) internal pure returns (string memory) {
        return string.concat("ipfs://", cid);
    }

    function tokenJSON(uint256 tokenId, string memory imageURI) internal pure returns (string memory) {
        return string.concat('{"image":"', imageURI, '","name":"Purplecheck #', tokenId.toString(), '"}');
    }

    function contractJSON() internal pure returns (string memory) {
        return
        '{"name":"Purplecheck","image":"ipfs://bafkreibhw7wybdzmpg5tfjr6pjynalpeb3zs7c3va26prjyc6gl2bvo7y4","description":"Your JPEGs deserve to feel special."}';
    }

    function contractURI() internal pure returns (string memory) {
        return toDataURI(contractJSON());
    }

    function tokenURI(uint256 tokenId, string memory imageURI) internal pure returns (string memory) {
        return toDataURI(tokenJSON(tokenId, imageURI));
    }

    function toDataURI(string memory json) internal pure returns (string memory) {
        return string.concat("data:application/json;base64,", Base64.encode(abi.encodePacked(json)));
    }
}

// File: src/Purplecheck.sol



// SPDX-License-Identifier: AGPL-3.0-or-later

pragma solidity ^0.8.13;

import {ERC721} from "solmate/tokens/ERC721.sol";
import {Owned} from "solmate/auth/Owned.sol";
import {LinearVRGDA} from "VRGDAs/LinearVRGDA.sol";
import {SafeTransferLib} from "solmate/utils/SafeTransferLib.sol";
import {toDaysWadUnsafe} from "solmate/utils/SignedWadMath.sol";

import {Metadata} from "./Metadata.sol";

/// @title Purplecheck - Your JPEGs deserve to feel special.
/// @notice Mint an ERC721 token associated with an IPFS content ID.
/// Mint price is calculated by a linear VRGDA targeting 6.9 purplechecks
/// per day at a price of 0.00420 ETH.
/// @author horsefacts <horsefacts@terminally.online>
contract Purplecheck is ERC721, LinearVRGDA, Owned {
    /// @notice Total number of Purplecheck tokens.
    uint256 public totalSupply;

    /// @notice Mint start time. Used in VRGDA price calculations.
    uint256 public immutable startTime = block.timestamp;

    /// @notice tokenId => IPFS CIDv1
    mapping(uint256 => string) public cid;

    constructor(address owner)
        ERC721("Purplecheck", unicode"🟪️✅")
        // Target rate 6.9 per day @ 0.00420 ETH
        LinearVRGDA(0.0042e18, 0.31e18, 6.9e18)
        Owned(owner)
    {}

    /// @notice Get the contract URI for this contract, encoded as a data URI.
    /// @return Contract metadata URI.
    function contractURI() external pure returns (string memory) {
        return Metadata.contractURI();
    }

    /// @notice Get the metadata URI for the given token ID, encoded as a data URI.
    /// @param tokenId uint256 token ID.
    /// @return Metadata URI.
    function tokenURI(uint256 tokenId) public view override returns (string memory) {
        return Metadata.tokenURI(tokenId, imageURI(tokenId));
    }

    /// @notice Get the IPFS image URI for the given token ID.
    /// @param tokenId uint256 token ID.
    /// @return URI of given token ID.
    function imageURI(uint256 tokenId) public view returns (string memory) {
        return Metadata.toImageURI(cid[tokenId]);
    }

    /// @notice Current mint price of a Purplecheck token, based on block.timestamp.
    /// @return uint256 mint price in wei.
    function price() public view returns (uint256) {
        return getVRGDAPrice(toDaysWadUnsafe(block.timestamp - startTime), totalSupply);
    }

    /// @notice Mint a Purplecheck token.
    /// @param _cid IPFS CIDv1 of the associated image.
    /// @return tokenId uint256 token ID.
    function mint(string calldata _cid) external payable returns (uint256 tokenId) {
        unchecked {
            // Get current VRGDA price
            uint256 _price = price();

            // Revert if caller has underpaid
            require(msg.value >= _price, "UNDERPAID");

            // Increment total supply and store image CID
            cid[tokenId = ++totalSupply] = _cid;

            // Mint token to caller
            _mint(msg.sender, tokenId);

            // Refund excess payment to caller
            if (msg.value != _price) SafeTransferLib.safeTransferETH(msg.sender, msg.value - _price);
        }
    }

    /// @notice Burn a Purplecheck token. Must be owner or approved.
    /// @param tokenId uint256 token ID.
    function burn(uint256 tokenId) external {
        address owner = _ownerOf[tokenId];

        require(
            msg.sender == owner || isApprovedForAll[owner][msg.sender] || msg.sender == getApproved[tokenId],
            "NOT_AUTHORIZED"
        );
        _burn(tokenId);
    }

    /// @notice Revert on attempted transfer.
    function transferFrom(address, address, uint256) public pure override {
        revert("TRANSFERS_DISABLED");
    }

    /// @notice Withdraw full balance to given recipient address.
    function withdrawBalance(address to) external onlyOwner {
        SafeTransferLib.safeTransferETH(to, address(this).balance);
    }
}