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

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import {RaidGeldUtils} from "../src/RaidGeldUtils.sol";
import {Army, Player, Raider} from "../src/RaidGeldStructs.sol";

contract RaidGeld is ERC20, Ownable {
    uint256 public constant MANTISSA = 1e4;

    uint256 public constant BUY_IN_AMOUNT = 0.00005 ether;
    uint256 public constant INITIAL_GELD = 50 * MANTISSA;

    mapping(address => Player) private players;
    mapping(address => Army) private armies;

    // Modifier for functions that should only be available to registered players
    modifier onlyPlayer() {
        require(players[msg.sender].created_at != 0, "Not an initiated player");
        _;
    }

    constructor() ERC20("Raid Geld", "GELD") Ownable(msg.sender) {}

    // This effectively registers the user
    function register() external payable {
        require(players[msg.sender].created_at == 0, "Whoops, player already exists :)");
        require(msg.value == BUY_IN_AMOUNT, "Incorrect buy in amount");

        // Mint some starting tokens to the player
        _mint(msg.sender, INITIAL_GELD);

        // Set initial states
        players[msg.sender] =
            Player({total_minted: INITIAL_GELD, created_at: block.timestamp, last_raided_at: block.timestamp});
        armies[msg.sender] = Army({
            moloch_denier: Raider({level: 0}),
            apprentice: Raider({level: 0}),
            anointed: Raider({level: 0}),
            champion: Raider({level: 0}),
            profit_per_second: 0
        });
    }

    // Override for default number of decimals
    function decimals() public view virtual override returns (uint8) {
        return 4;
    }

    // Allows the owner to withdraw
    function withdraw() external onlyOwner {
        payable(owner()).transfer(address(this).balance);
    }

    // Manual minting for itchy fingers
    function raid() external onlyPlayer {
        performRaid(msg.sender);
    }

    // Helper so we can use it when buying units too
    function performRaid(address player) private {
        uint256 time_past = block.timestamp - players[player].last_raided_at;
        uint256 new_geld = armies[player].profit_per_second * time_past;

        // TODO: Pink noise, make it so sometimes its better than expected

        _mint(player, new_geld);
        players[player].last_raided_at = block.timestamp;
        players[player].total_minted += new_geld;
    }

    // Function to get Player struct
    function getPlayer(address addr) public view returns (Player memory) {
        return players[addr];
    }

    // Function to get Army struct
    function getArmy(address addr) public view returns (Army memory) {
        return armies[addr];
    }

    // Quick fn to check if user is registered
    function isRegistered(address addr) public view returns (bool) {
        return players[addr].created_at != 0;
    }

    // Add a unit to your army
    function addUnit(uint8 unit, uint16 n_units) external onlyPlayer {
        require(unit <= 3, "Unknown unit");

        Army storage army = armies[msg.sender];
        uint16 currentLevel = 0;
        if (unit == 0) {
            // moloch_denier
            currentLevel = army.moloch_denier.level;
        } else if (unit == 1) {
            // apprentice
            currentLevel = army.apprentice.level;
        } else if (unit == 2) {
            // anointed
            currentLevel = army.anointed.level;
        } else if (unit == 3) {
            // champion
            currentLevel = army.champion.level;
        }

        uint256 cost = RaidGeldUtils.calculateUnitPrice(unit, currentLevel, n_units);
        // First trigger a raid so player receives what he is due at to this moment
        
        uint256 time_past = block.timestamp - players[msg.sender].last_raided_at;
        uint256 new_geld = armies[msg.sender].profit_per_second * time_past;
        require(balanceOf(msg.sender) + new_geld > cost, "Not enough GELD to add this unit");
        performRaid(msg.sender);

        // TODO: Since we are first minting then burning the token, this could be simplified
        // by first calculating the difference and then minting / burning in just one operation

        // then burn the cost of the new army
        _burn(msg.sender, cost);

        // Increase level
        if (unit == 0) {
            // moloch_denier
            army.moloch_denier.level += n_units;
        } else if (unit == 1) {
            // apprentice
            army.apprentice.level += n_units;
        } else if (unit == 2) {
            // anointed
            army.anointed.level += n_units;
        } else if (unit == 3) {
            // champion
            army.champion.level += n_units;
        }

        // update profite per second
        army.profit_per_second = RaidGeldUtils.calculateProfitsPerSecond(army);
    }

    receive() external payable {
        revert("No plain Ether accepted, use register() function to check in :)");
    }

    // Revert any non-function-call Ether transfers or calls to non-existent functions
    fallback() external payable {
        revert("No fallback calls accepted");
    }
}