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// SPDX-License-Identifier: MIT
pragma solidity ^0.8.30;

import {Love} from "../src/Love.sol";
import {IERC20Errors} from "@openzeppelin/contracts/interfaces/draft-IERC6093.sol";
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {Test} from "forge-std/Test.sol";

contract LoveTest is Test {
    Love public love;

    address alice = makeAddr("alice");
    address bob = makeAddr("bob");
    address stranger = makeAddr("stranger");

    function setUp() public {
        love = new Love();
    }

    /*//////////////////////////////////////////////////////////////
                                METADATA
    //////////////////////////////////////////////////////////////*/

    function test_Metadata() public view {
        assertEq(love.name(), "Love");
        assertEq(love.symbol(), "LOVE");
        assertEq(love.decimals(), 18);
    }

    function test_InitialSupplyIsZero() public view {
        assertEq(love.totalSupply(), 0);
    }

    /*//////////////////////////////////////////////////////////////
                                  MINT
    //////////////////////////////////////////////////////////////*/

    function test_Mint() public {
        vm.prank(alice);
        love.mint(alice, 100e18);

        assertEq(love.balanceOf(alice), 100e18);
        assertEq(love.totalSupply(), 100e18);
    }

    /// @dev The point of this contract: `mint` has no access control.
    function test_AnyoneCanMintToAnyone() public {
        vm.prank(stranger);
        love.mint(bob, 1000e18);

        assertEq(love.balanceOf(bob), 1000e18);
        assertEq(love.balanceOf(stranger), 0);
        assertEq(love.totalSupply(), 1000e18);
    }

    function test_MintEmitsTransferFromZero() public {
        vm.expectEmit(true, true, false, true);
        emit IERC20.Transfer(address(0), alice, 5e18);

        vm.prank(alice);
        love.mint(alice, 5e18);
    }

    function test_MintAccumulates() public {
        vm.startPrank(alice);
        love.mint(alice, 1e18);
        love.mint(alice, 2e18);
        vm.stopPrank();

        assertEq(love.balanceOf(alice), 3e18);
        assertEq(love.totalSupply(), 3e18);
    }

    function test_RevertWhen_MintingToZeroAddress() public {
        vm.expectRevert(abi.encodeWithSelector(IERC20Errors.ERC20InvalidReceiver.selector, address(0)));
        love.mint(address(0), 1e18);
    }

    function test_RevertWhen_MintOverflowsTotalSupply() public {
        love.mint(alice, type(uint256).max);

        vm.expectRevert();
        love.mint(bob, 1);
    }

    /*//////////////////////////////////////////////////////////////
                                TRANSFER
    //////////////////////////////////////////////////////////////*/

    function test_Transfer() public {
        love.mint(alice, 10e18);

        vm.prank(alice);
        assertTrue(love.transfer(bob, 4e18));

        assertEq(love.balanceOf(alice), 6e18);
        assertEq(love.balanceOf(bob), 4e18);
    }

    function test_RevertWhen_TransferExceedsBalance() public {
        love.mint(alice, 1e18);

        vm.prank(alice);
        vm.expectRevert(abi.encodeWithSelector(IERC20Errors.ERC20InsufficientBalance.selector, alice, 1e18, 2e18));
        // forge-lint: disable-next-line(erc20-unchecked-transfer)
        love.transfer(bob, 2e18);
    }

    /*//////////////////////////////////////////////////////////////
                          APPROVE / TRANSFERFROM
    //////////////////////////////////////////////////////////////*/

    function test_ApproveAndTransferFrom() public {
        love.mint(alice, 10e18);

        vm.prank(alice);
        assertTrue(love.approve(bob, 6e18));
        assertEq(love.allowance(alice, bob), 6e18);

        vm.prank(bob);
        assertTrue(love.transferFrom(alice, stranger, 6e18));

        assertEq(love.balanceOf(alice), 4e18);
        assertEq(love.balanceOf(stranger), 6e18);
        assertEq(love.allowance(alice, bob), 0);
    }

    function test_RevertWhen_TransferFromExceedsAllowance() public {
        love.mint(alice, 10e18);

        vm.prank(alice);
        love.approve(bob, 1e18);

        vm.prank(bob);
        vm.expectRevert(abi.encodeWithSelector(IERC20Errors.ERC20InsufficientAllowance.selector, bob, 1e18, 2e18));
        // forge-lint: disable-next-line(erc20-unchecked-transfer)
        love.transferFrom(alice, stranger, 2e18);
    }

    /*//////////////////////////////////////////////////////////////
                                  FUZZ
    //////////////////////////////////////////////////////////////*/

    function testFuzz_MintByAnyCaller(address caller, address to, uint256 amount) public {
        vm.assume(to != address(0));

        vm.prank(caller);
        love.mint(to, amount);

        assertEq(love.balanceOf(to), amount);
        assertEq(love.totalSupply(), amount);
    }

    function testFuzz_Transfer(uint256 minted, uint256 amount) public {
        amount = bound(amount, 0, minted);

        love.mint(alice, minted);

        vm.prank(alice);
        assertTrue(love.transfer(bob, amount));

        assertEq(love.balanceOf(alice), minted - amount);
        assertEq(love.balanceOf(bob), amount);
    }
}