// SPDX-License-Identifier: GPL-3.0
pragma solidity 0.8.19; 



    
//****************************************************************************//
//---------------------        MAIN CODE STARTS HERE     ---------------------//
//****************************************************************************//
    
contract RAMOToken {
    

    /*===============================
    =         DATA STORAGE          =
    ===============================*/

    // Public variables of the token
    string constant public name = "RAMO coin";
    string constant public symbol = "RAMO";
    uint256 constant public decimals = 18;
    uint256 constant public maxSupply = 500000000 * (10**decimals);   //500 million tokens
    uint256 public totalSupply;
    bool public safeguard;      //putting safeguard on will halt all non-owner functions
    
    
    // This creates a mapping with all data storage
    mapping (address => uint256) public balanceOf;
    mapping (address => mapping (address => uint256)) public allowance;
    mapping (address => bool) public frozenAccount;


    /*===============================
    =         PUBLIC EVENTS         =
    ===============================*/

    // This generates a public event of token transfer
    event Transfer(address indexed from, address indexed to, uint256 value);

    // This notifies clients about the amount burnt
    event Burn(address indexed from, uint256 value);
        
    // This generates a public event for frozen (blacklisting) accounts
    event FrozenAccounts(address target, bool frozen);
    
    // This will log approval of token Transfer
    event Approval(address indexed from, address indexed spender, uint256 value);



    /*======================================
    =       STANDARD ERC20 FUNCTIONS       =
    ======================================*/

    /* Internal transfer, only can be called by this contract */
    function _transfer(address _from, address _to, uint _value) internal {
        
        //checking conditions
        require(!safeguard);
        require(!frozenAccount[_from]);                     // Check if sender is frozen
        require(!frozenAccount[_to]);                       // Check if recipient is frozen
        
        // overflow and undeflow checked by SafeMath Library
        balanceOf[_from] = balanceOf[_from] - (_value);    // Subtract from the sender
        balanceOf[_to] = balanceOf[_to] + (_value);        // Add the same to the recipient
        
        // emit Transfer event
        emit Transfer(_from, _to, _value);
    }

    /**
        * Transfer tokens
        *
        * Send `_value` tokens to `_to` from your account
        *
        * @param _to The address of the recipient
        * @param _value the amount to send
        */
    function transfer(address _to, uint256 _value) public returns (bool success) {
        
        //no need to check for input validations, as that is ruled by SafeMath
        _transfer(msg.sender, _to, _value);
        
        return true;
    }

    /**
        * Transfer tokens from other address
        *
        * Send `_value` tokens to `_to` in behalf of `_from`
        *
        * @param _from The address of the sender
        * @param _to The address of the recipient
        * @param _value the amount to send
        */
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
        allowance[_from][msg.sender] = allowance[_from][msg.sender] - (_value);
        _transfer(_from, _to, _value);
        return true;
    }

    /**
        * Set allowance for other address
        *
        * Allows `_spender` to spend no more than `_value` tokens in your behalf
        *
        * @param _spender The address authorized to spend
        * @param _value the max amount they can spend
        */
    function approve(address _spender, uint256 _value) public returns (bool success) {
        require(!safeguard);
        require(balanceOf[msg.sender] >= _value, "Balance does not have enough tokens");
        allowance[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value);
        return true;
    }


    /*=====================================
    =       CUSTOM PUBLIC FUNCTIONS       =
    ======================================*/
    
    constructor() {
        
        totalSupply = maxSupply;
        
        //sending all the tokens to Owner
        balanceOf[msg.sender] = totalSupply;
        
        //firing event which logs this transaction
        emit Transfer(address(0), msg.sender, totalSupply);
    }
    
   
    /**
        * Destroy tokens
        *
        * Remove `_value` tokens from the system irreversibly
        *
        * @param _value the amount of money to burn
        */
    function burn(uint256 _value) public returns (bool success) {
        //checking of enough token balance is done by SafeMath
        balanceOf[msg.sender] = balanceOf[msg.sender] - (_value);  // Subtract from the sender
        totalSupply = totalSupply - (_value);                      // Updates totalSupply
        emit Burn(msg.sender, _value);
        emit Transfer(msg.sender, address(0), _value);
        return true;
    }

  
   




   
    

}