// SPDX-License-Identifier: MIT
pragma solidity 0.8.35;

import {IERC20Errors} from "@openzeppelin/contracts/interfaces/draft-IERC6093.sol";
import {PausableUpgradeable} from "@openzeppelin/contracts-upgradeable/utils/PausableUpgradeable.sol";
import {ReentrancyGuardTransient} from "@openzeppelin/contracts/utils/ReentrancyGuardTransient.sol";
import {Upgrades} from "openzeppelin-foundry-upgrades/Upgrades.sol";

import {BankV1} from "../src/BankV1.sol";
import {BankTestBase} from "./helpers/BankTestBase.sol";
import {FeeOnTransferToken} from "./mocks/FeeOnTransferToken.sol";
import {ReentrantToken} from "./mocks/ReentrantToken.sol";

event Deposited(address indexed account, uint256 amount);
event Withdrawn(address indexed account, uint256 amount);

error ZeroAmount();
error InsufficientBalance(address account, uint256 available, uint256 requested);
error UnexpectedAssetDelta(uint256 expected, uint256 actual);

contract BankV1CustodyTest is BankTestBase {
    uint256 private constant MAX_DEPOSIT = 1_000_000e6;

    function testDepositCreditsExactCustomerAndLiabilityAgainstReceivedReserves() public {
        _mintAndApprove(alice, 1_000e6, 100e6);

        vm.prank(alice);
        bank.deposit(100e6);

        assertEq(token.balanceOf(alice), 900e6);
        assertEq(token.balanceOf(proxy), 100e6);
        assertEq(bank.balanceOf(alice), 100e6);
        assertEq(bank.totalLiabilities(), 100e6);
    }

    function testDepositEmitsDepositedEvent() public {
        _mintAndApprove(alice, 100e6, 100e6);

        vm.expectEmit(true, false, false, true, proxy);
        emit Deposited(alice, 100e6);
        vm.prank(alice);
        bank.deposit(100e6);
    }

    function testDepositRejectsZeroAmount() public {
        vm.prank(alice);
        vm.expectRevert(ZeroAmount.selector);
        bank.deposit(0);
    }

    function testDepositRejectsCallsWhilePaused() public {
        _mintAndApprove(alice, 100e6, 100e6);
        vm.prank(owner);
        bank.pause();

        vm.prank(alice);
        vm.expectRevert(PausableUpgradeable.EnforcedPause.selector);
        bank.deposit(100e6);
    }

    function testDepositRollsBackWhenAllowanceIsInadequate() public {
        _mintAndApprove(alice, 100e6, 99e6);

        vm.prank(alice);
        vm.expectRevert(abi.encodeWithSelector(IERC20Errors.ERC20InsufficientAllowance.selector, proxy, 99e6, 100e6));
        bank.deposit(100e6);

        _assertEmptyAccounting(alice);
        assertEq(token.balanceOf(alice), 100e6);
    }

    function testDepositRollsBackWhenWalletBalanceIsInadequate() public {
        _mintAndApprove(alice, 99e6, 100e6);

        vm.prank(alice);
        vm.expectRevert(abi.encodeWithSelector(IERC20Errors.ERC20InsufficientBalance.selector, alice, 99e6, 100e6));
        bank.deposit(100e6);

        _assertEmptyAccounting(alice);
        assertEq(token.balanceOf(alice), 99e6);
    }

    function testDepositsKeepTwoCustomersAccountingIndependent() public {
        _mintAndApprove(alice, 1_000e6, 300e6);
        _mintAndApprove(bob, 1_000e6, 700e6);

        vm.prank(alice);
        bank.deposit(300e6);
        vm.prank(bob);
        bank.deposit(700e6);

        assertEq(bank.balanceOf(alice), 300e6);
        assertEq(bank.balanceOf(bob), 700e6);
        assertEq(bank.totalLiabilities(), 1_000e6);
        assertEq(token.balanceOf(proxy), 1_000e6);
    }

    function testFeeOnTransferDepositRevertsAndRollsBackTokenAndAccounting() public {
        FeeOnTransferToken feeToken = new FeeOnTransferToken();
        BankV1 feeBank = _deployBank(address(feeToken));
        feeToken.mint(alice, 100e6);
        vm.prank(alice);
        feeToken.approve(address(feeBank), 100e6);

        vm.prank(alice);
        vm.expectRevert(abi.encodeWithSelector(UnexpectedAssetDelta.selector, 100e6, 99e6));
        feeBank.deposit(100e6);

        assertEq(feeToken.balanceOf(alice), 100e6);
        assertEq(feeToken.balanceOf(address(feeBank)), 0);
        assertEq(feeBank.balanceOf(alice), 0);
        assertEq(feeBank.totalLiabilities(), 0);
    }

    function testDepositSwallowsNestedRevertAndCreditsOnlyOnce() public {
        ReentrantToken reentrantToken = new ReentrantToken();
        BankV1 reentrantBank = _deployBank(address(reentrantToken));
        reentrantToken.mint(alice, 100e6);
        vm.prank(alice);
        reentrantToken.approve(address(reentrantBank), 100e6);
        reentrantToken.configureDepositCallback(address(reentrantBank), false);

        vm.prank(alice);
        reentrantBank.deposit(100e6);

        assertTrue(reentrantToken.nestedCallAttempted());
        assertFalse(reentrantToken.nestedCallSucceeded());
        assertEq(reentrantToken.nestedRevertSelector(), ReentrancyGuardTransient.ReentrancyGuardReentrantCall.selector);
        assertEq(reentrantToken.observedAccountBalance(), 0);
        assertEq(reentrantToken.observedLiabilities(), 0);
        assertEq(reentrantToken.balanceOf(alice), 0);
        assertEq(reentrantToken.balanceOf(address(reentrantBank)), 100e6);
        assertEq(reentrantBank.balanceOf(alice), 100e6);
        assertEq(reentrantBank.totalLiabilities(), 100e6);
    }

    function testDepositPropagatesNestedRevertAtomicallyWhenConfigured() public {
        ReentrantToken reentrantToken = new ReentrantToken();
        BankV1 reentrantBank = _deployBank(address(reentrantToken));
        reentrantToken.mint(alice, 100e6);
        vm.prank(alice);
        reentrantToken.approve(address(reentrantBank), 100e6);
        reentrantToken.configureDepositCallback(address(reentrantBank), true);

        vm.prank(alice);
        vm.expectRevert(ReentrancyGuardTransient.ReentrancyGuardReentrantCall.selector);
        reentrantBank.deposit(100e6);

        assertEq(reentrantToken.balanceOf(alice), 100e6);
        assertEq(reentrantToken.balanceOf(address(reentrantBank)), 0);
        assertEq(reentrantBank.balanceOf(alice), 0);
        assertEq(reentrantBank.totalLiabilities(), 0);
    }

    function testWithdrawDebitsExactCustomerLiabilityAndReserves() public {
        _deposit(alice, 1_000e6);

        vm.prank(alice);
        bank.withdraw(400e6);

        assertEq(token.balanceOf(alice), 400e6);
        assertEq(token.balanceOf(proxy), 600e6);
        assertEq(bank.balanceOf(alice), 600e6);
        assertEq(bank.totalLiabilities(), 600e6);
    }

    function testWithdrawEmitsWithdrawnEvent() public {
        _deposit(alice, 100e6);

        vm.expectEmit(true, false, false, true, proxy);
        emit Withdrawn(alice, 40e6);
        vm.prank(alice);
        bank.withdraw(40e6);
    }

    function testWithdrawRejectsZeroAmount() public {
        vm.prank(alice);
        vm.expectRevert(ZeroAmount.selector);
        bank.withdraw(0);
    }

    function testWithdrawRejectsCallsWhilePaused() public {
        _deposit(alice, 100e6);
        vm.prank(owner);
        bank.pause();

        vm.prank(alice);
        vm.expectRevert(PausableUpgradeable.EnforcedPause.selector);
        bank.withdraw(100e6);
    }

    function testWithdrawReportsAvailableAndRequestedOnInsufficientInternalBalance() public {
        _deposit(alice, 40e6);

        vm.prank(alice);
        vm.expectRevert(abi.encodeWithSelector(InsufficientBalance.selector, alice, 40e6, 41e6));
        bank.withdraw(41e6);

        assertEq(bank.balanceOf(alice), 40e6);
        assertEq(bank.totalLiabilities(), 40e6);
        assertEq(token.balanceOf(proxy), 40e6);
    }

    function testWithdrawUpdatesAccountingBeforeTransferCallbackAndCannotDoubleDebit() public {
        ReentrantToken reentrantToken = new ReentrantToken();
        BankV1 reentrantBank = _deployBank(address(reentrantToken));
        reentrantToken.mint(alice, 100e6);
        vm.prank(alice);
        reentrantToken.approve(address(reentrantBank), 100e6);
        vm.prank(alice);
        reentrantBank.deposit(100e6);
        reentrantToken.configureWithdrawalCallback(address(reentrantBank), false);

        vm.prank(alice);
        reentrantBank.withdraw(40e6);

        assertEq(reentrantToken.observedAccountBalance(), 60e6);
        assertEq(reentrantToken.observedLiabilities(), 60e6);
        assertTrue(reentrantToken.nestedCallAttempted());
        assertFalse(reentrantToken.nestedCallSucceeded());
        assertEq(reentrantToken.nestedRevertSelector(), ReentrancyGuardTransient.ReentrancyGuardReentrantCall.selector);
        assertEq(reentrantToken.balanceOf(alice), 40e6);
        assertEq(reentrantToken.balanceOf(address(reentrantBank)), 60e6);
        assertEq(reentrantBank.balanceOf(alice), 60e6);
        assertEq(reentrantBank.totalLiabilities(), 60e6);
    }

    function testOneCustomersWithdrawalLeavesOtherCustomerUnchanged() public {
        _deposit(alice, 100e6);
        _deposit(bob, 200e6);

        vm.prank(alice);
        bank.withdraw(40e6);

        assertEq(bank.balanceOf(alice), 60e6);
        assertEq(bank.balanceOf(bob), 200e6);
        assertEq(bank.totalLiabilities(), 260e6);
        assertEq(token.balanceOf(proxy), 260e6);
    }

    function testDirectTransferCreatesSurplusThatRemainsAfterFullWithdrawal() public {
        _deposit(alice, 100e6);
        vm.prank(owner);
        token.mint(bob, 25e6);
        vm.prank(bob);
        token.transfer(proxy, 25e6);

        assertEq(token.balanceOf(proxy), 125e6);
        assertEq(bank.totalLiabilities(), 100e6);

        vm.prank(alice);
        bank.withdraw(100e6);

        assertEq(token.balanceOf(proxy), 25e6);
        assertEq(bank.balanceOf(alice), 0);
        assertEq(bank.totalLiabilities(), 0);
    }

    function testFuzzDepositPreservesExactAccounting(uint256 amountSeed) public {
        uint256 amount = bound(amountSeed, 1, MAX_DEPOSIT);
        _mintAndApprove(alice, amount, amount);

        vm.prank(alice);
        bank.deposit(amount);

        assertEq(token.balanceOf(alice), 0);
        assertEq(token.balanceOf(proxy), amount);
        assertEq(bank.balanceOf(alice), amount);
        assertEq(bank.totalLiabilities(), amount);
    }

    function testFuzzWithdrawPreservesExactAccounting(uint256 depositSeed, uint256 withdrawalSeed) public {
        uint256 deposited = bound(depositSeed, 1, MAX_DEPOSIT);
        uint256 withdrawn = bound(withdrawalSeed, 1, deposited);
        _deposit(alice, deposited);

        vm.prank(alice);
        bank.withdraw(withdrawn);

        uint256 remaining = deposited - withdrawn;
        assertEq(token.balanceOf(alice), withdrawn);
        assertEq(token.balanceOf(proxy), remaining);
        assertEq(bank.balanceOf(alice), remaining);
        assertEq(bank.totalLiabilities(), remaining);
    }

    function testFuzzOverWithdrawAlwaysReverts(uint256 depositSeed, uint256 excessSeed) public {
        uint256 deposited = bound(depositSeed, 1, MAX_DEPOSIT);
        uint256 excess = bound(excessSeed, 1, MAX_DEPOSIT);
        uint256 requested = deposited + excess;
        _deposit(alice, deposited);

        vm.prank(alice);
        vm.expectRevert(abi.encodeWithSelector(InsufficientBalance.selector, alice, deposited, requested));
        bank.withdraw(requested);

        assertEq(bank.balanceOf(alice), deposited);
        assertEq(bank.totalLiabilities(), deposited);
        assertEq(token.balanceOf(proxy), deposited);
    }

    function _mintAndApprove(address account, uint256 mintAmount, uint256 approveAmount) private {
        vm.prank(owner);
        token.mint(account, mintAmount);
        vm.prank(account);
        token.approve(proxy, approveAmount);
    }

    function _deposit(address account, uint256 amount) private {
        _mintAndApprove(account, amount, amount);
        vm.prank(account);
        bank.deposit(amount);
    }

    function _deployBank(address asset_) private returns (BankV1 deployedBank) {
        address deployedProxy =
            Upgrades.deployUUPSProxy("BankV1.sol:BankV1", abi.encodeCall(BankV1.initialize, (asset_, owner)));
        deployedBank = BankV1(deployedProxy);
    }

    function _assertEmptyAccounting(address account) private view {
        assertEq(token.balanceOf(proxy), 0);
        assertEq(bank.balanceOf(account), 0);
        assertEq(bank.totalLiabilities(), 0);
    }
}