pragma solidity ^0.4.20;
contract POMDA {
/*=================================
=            MODIFIERS            =
=================================*/
// only people with tokens
modifier onlyBagholders() {
require(myTokens() > 0);
_;
}

// only people with profits
modifier onlyStronghands() {
require(myDividends(true) > 0);
_;
}

/*==============================
=            EVENTS            =
==============================*/
event onTokenPurchase(
address indexed customerAddress,
uint256 incomingEthereum,
uint256 tokensMinted,
address indexed referredBy
);

event onTokenSell(
address indexed customerAddress,
uint256 tokensBurned,
uint256 ethereumEarned
);

event onReinvestment(
address indexed customerAddress,
uint256 ethereumReinvested,
uint256 tokensMinted
);

event onWithdraw(
address indexed customerAddress,
uint256 ethereumWithdrawn
);

// ERC20
event Transfer(
address indexed from,
address indexed to,
uint256 tokens
);


/*=====================================
=            CONFIGURABLES            =
=====================================*/
string public name = "POMDA";
string public symbol = "POMDA";
uint8 constant public decimals = 18;
uint8 constant internal dividendFee_ = 10;
uint256 constant internal tokenPriceInitial_ = 0.0000001 ether;
uint256 constant internal tokenPriceIncremental_ = 0.00000001 ether;
uint256 constant internal magnitude = 2**64;

// proof of stake (defaults at 100 tokens)
uint256 public stakingRequirement = 100e18;

// ambassador program
mapping(address => bool) internal ambassadors_;
uint256 constant internal ambassadorMaxPurchase_ = 1 ether;
uint256 constant internal ambassadorQuota_ = 20 ether;



/*================================
=            DATASETS            =
================================*/
// amount of shares for each address (scaled number)
mapping(address => uint256) internal tokenBalanceLedger_;
mapping(address => uint256) internal referralBalance_;
mapping(address => int256) internal payoutsTo_;
uint256 internal tokenSupply_ = 0;
uint256 internal profitPerShare_;





/*=======================================
=            PUBLIC FUNCTIONS            =
=======================================*/
/*
* -- APPLICATION ENTRY POINTS --  
*/
function POMDA()
public
{
        
}
function buy(address _referredBy)
public
payable
returns(uint256)
{
purchaseTokens(msg.value, _referredBy);
}

/**
* Fallback function to handle ethereum that was send straight to the contract
* Unfortunately we cannot use a referral address this way.
*/
function()
payable
public
{
purchaseTokens(msg.value, 0x0);
}

/**
* Converts all of caller's dividends to tokens.
*/
function reinvest()
onlyStronghands()
public
{
// fetch dividends
uint256 _dividends = myDividends(false); // retrieve ref. bonus later in the code

// pay out the dividends virtually
address _customerAddress = msg.sender;
payoutsTo_[_customerAddress] +=  (int256) (_dividends * magnitude);

// retrieve ref. bonus
_dividends += referralBalance_[_customerAddress];
referralBalance_[_customerAddress] = 0;

// dispatch a buy order with the virtualized "withdrawn dividends"
uint256 _tokens = purchaseTokens(_dividends, 0x0);

// fire event
onReinvestment(_customerAddress, _dividends, _tokens);
}

/**
* Alias of sell() and withdraw().
*/
function exit()
public
{
// get token count for caller & sell them all
address _customerAddress = msg.sender;
uint256 _tokens = tokenBalanceLedger_[_customerAddress];
if(_tokens > 0) sell(_tokens);

// lambo delivery service
withdraw();
}

/**
* Withdraws all of the callers earnings.
*/
function withdraw()
onlyStronghands()
public
{
// setup data
address _customerAddress = msg.sender;
uint256 _dividends = myDividends(false); // get ref. bonus later in the code

// update dividend tracker
payoutsTo_[_customerAddress] +=  (int256) (_dividends * magnitude);

// add ref. bonus
_dividends += referralBalance_[_customerAddress];
referralBalance_[_customerAddress] = 0;

// lambo delivery service
_customerAddress.transfer(_dividends);

// fire event
onWithdraw(_customerAddress, _dividends);
}

/**
* Liquifies tokens to ethereum.
*/
function sell(uint256 _amountOfTokens)
onlyBagholders()
public
{
// setup data
address _customerAddress = msg.sender;
// russian hackers BTFO
require(_amountOfTokens <= tokenBalanceLedger_[_customerAddress]);
uint256 _tokens = _amountOfTokens;
uint256 _ethereum = tokensToEthereum_(_tokens);
uint256 _dividends = SafeMath.div(_ethereum, dividendFee_);
uint256 _taxedEthereum = SafeMath.sub(_ethereum, _dividends);

// burn the sold tokens
tokenSupply_ = SafeMath.sub(tokenSupply_, _tokens);
tokenBalanceLedger_[_customerAddress] = SafeMath.sub(tokenBalanceLedger_[_customerAddress], _tokens);

// update dividends tracker
int256 _updatedPayouts = (int256) (profitPerShare_ * _tokens + (_taxedEthereum * magnitude));
payoutsTo_[_customerAddress] -= _updatedPayouts;       

// dividing by zero is a bad idea
if (tokenSupply_ > 0) {
// update the amount of dividends per token
profitPerShare_ = SafeMath.add(profitPerShare_, (_dividends * magnitude) / tokenSupply_);
}

// fire event
onTokenSell(_customerAddress, _tokens, _taxedEthereum);
}


/**
* Transfer tokens from the caller to a new holder.
* Remember, there's a 10% fee here as well.
*/
function transfer(address _toAddress, uint256 _amountOfTokens)
onlyBagholders()
public
returns(bool)
{
// setup
address _customerAddress = msg.sender;

// make sure we have the requested tokens
// also disables transfers until ambassador phase is over
// ( we dont want whale premines )
//require(!onlyAmbassadors && _amountOfTokens <= tokenBalanceLedger_[_customerAddress]);

// withdraw all outstanding dividends first
if(myDividends(true) > 0) withdraw();

// liquify 10% of the tokens that are transfered
// these are dispersed to shareholders
uint256 _tokenFee = SafeMath.div(_amountOfTokens, dividendFee_);
uint256 _taxedTokens = SafeMath.sub(_amountOfTokens, _tokenFee);
uint256 _dividends = tokensToEthereum_(_tokenFee);

// burn the fee tokens
tokenSupply_ = SafeMath.sub(tokenSupply_, _tokenFee);

// exchange tokens
tokenBalanceLedger_[_customerAddress] = SafeMath.sub(tokenBalanceLedger_[_customerAddress], _amountOfTokens);
tokenBalanceLedger_[_toAddress] = SafeMath.add(tokenBalanceLedger_[_toAddress], _taxedTokens);

// update dividend trackers
payoutsTo_[_customerAddress] -= (int256) (profitPerShare_ * _amountOfTokens);
payoutsTo_[_toAddress] += (int256) (profitPerShare_ * _taxedTokens);

// disperse dividends among holders
profitPerShare_ = SafeMath.add(profitPerShare_, (_dividends * magnitude) / tokenSupply_);

// fire event
Transfer(_customerAddress, _toAddress, _taxedTokens);

// ERC20
return true;

}


/*----------  HELPERS AND CALCULATORS  ----------*/
/**
* Method to view the current Ethereum stored in the contract
* Example: totalEthereumBalance()
*/
function totalEthereumBalance()
public
view
returns(uint)
{
return this.balance;
}

/**
* Retrieve the total token supply.
*/
function totalSupply()
public
view
returns(uint256)
{
return tokenSupply_;
}

/**
* Retrieve the tokens owned by the caller.
*/
function myTokens()
public
view
returns(uint256)
{
address _customerAddress = msg.sender;
return balanceOf(_customerAddress);
}

/**
* Retrieve the dividends owned by the caller.
* If `_includeReferralBonus` is to to 1/true, the referral bonus will be included in the calculations.
* The reason for this, is that in the frontend, we will want to get the total divs (global + ref)
* But in the internal calculations, we want them separate. 
*/ 
function myDividends(bool _includeReferralBonus) 
public 
view 
returns(uint256)
{
address _customerAddress = msg.sender;
return _includeReferralBonus ? dividendsOf(_customerAddress) + referralBalance_[_customerAddress] : dividendsOf(_customerAddress) ;
}

/**
* Retrieve the token balance of any single address.
*/
function balanceOf(address _customerAddress)
view
public
returns(uint256)
{
return tokenBalanceLedger_[_customerAddress];
}

/**
* Retrieve the dividend balance of any single address.
*/
function dividendsOf(address _customerAddress)
view
public
returns(uint256)
{
return (uint256) ((int256)(profitPerShare_ * tokenBalanceLedger_[_customerAddress]) - payoutsTo_[_customerAddress]) / magnitude;
}

/**
* Return the buy price of 1 individual token.
*/
function sellPrice() 
public 
view 
returns(uint256)
{
// our calculation relies on the token supply, so we need supply. Doh.
if(tokenSupply_ == 0){
return tokenPriceInitial_ - tokenPriceIncremental_;
} else {
uint256 _ethereum = tokensToEthereum_(1e18);
uint256 _dividends = SafeMath.div(_ethereum, dividendFee_  );
uint256 _taxedEthereum = SafeMath.sub(_ethereum, _dividends);
return _taxedEthereum;
}
}

/**
* Return the sell price of 1 individual token.
*/
function buyPrice() 
public 
view 
returns(uint256)
{
// our calculation relies on the token supply, so we need supply. Doh.
if(tokenSupply_ == 0){
return tokenPriceInitial_ + tokenPriceIncremental_;
} else {
uint256 _ethereum = tokensToEthereum_(1e18);
uint256 _dividends = SafeMath.div(_ethereum, dividendFee_  );
uint256 _taxedEthereum = SafeMath.add(_ethereum, _dividends);
return _taxedEthereum;
}
}

/**
* Function for the frontend to dynamically retrieve the price scaling of buy orders.
*/
function calculateTokensReceived(uint256 _ethereumToSpend) 
public 
view 
returns(uint256)
{
uint256 _dividends = SafeMath.div(_ethereumToSpend, dividendFee_);
uint256 _taxedEthereum = SafeMath.sub(_ethereumToSpend, _dividends);
uint256 _amountOfTokens = ethereumToTokens_(_taxedEthereum);

return _amountOfTokens;
}

/**
* Function for the frontend to dynamically retrieve the price scaling of sell orders.
*/
function calculateEthereumReceived(uint256 _tokensToSell) 
public 
view 
returns(uint256)
{
require(_tokensToSell <= tokenSupply_);
uint256 _ethereum = tokensToEthereum_(_tokensToSell);
uint256 _dividends = SafeMath.div(_ethereum, dividendFee_);
uint256 _taxedEthereum = SafeMath.sub(_ethereum, _dividends);
return _taxedEthereum;
}


/*==========================================
=            INTERNAL FUNCTIONS            =
==========================================*/
function purchaseTokens(uint256 _incomingEthereum, address _referredBy)
//    antiEarlyWhale(_incomingEthereum)
internal
returns(uint256)
{
// data setup
address _customerAddress = msg.sender;
uint256 _undividedDividends = SafeMath.div(_incomingEthereum, dividendFee_);
uint256 _referralBonus = SafeMath.div(_undividedDividends, 3);
uint256 _dividends = SafeMath.sub(_undividedDividends, _referralBonus);
uint256 _taxedEthereum = SafeMath.sub(_incomingEthereum, _undividedDividends);
uint256 _amountOfTokens = ethereumToTokens_(_taxedEthereum);
uint256 _fee = _dividends * magnitude;

// no point in continuing execution if OP is a poorfag russian hacker
// prevents overflow in the case that the pyramid somehow magically starts being used by everyone in the world
// (or hackers)
// and yes we know that the safemath function automatically rules out the "greater then" equasion.
require(_amountOfTokens > 0 && (SafeMath.add(_amountOfTokens,tokenSupply_) > tokenSupply_));

// is the user referred by a masternode?
if(
// is this a referred purchase?
_referredBy != 0x0000000000000000000000000000000000000000 &&

// no cheating!
_referredBy != _customerAddress &&

// does the referrer have at least X whole tokens?
// i.e is the referrer a godly chad masternode
tokenBalanceLedger_[_referredBy] >= stakingRequirement
){
// wealth redistribution
referralBalance_[_referredBy] = SafeMath.add(referralBalance_[_referredBy], _referralBonus);
} else {
// no ref purchase
// add the referral bonus back to the global dividends cake
_dividends = SafeMath.add(_dividends, _referralBonus);
_fee = _dividends * magnitude;
}

// we can't give people infinite ethereum
if(tokenSupply_ > 0){

// add tokens to the pool
tokenSupply_ = SafeMath.add(tokenSupply_, _amountOfTokens);

// take the amount of dividends gained through this transaction, and allocates them evenly to each shareholder
profitPerShare_ += (_dividends * magnitude / (tokenSupply_));

// calculate the amount of tokens the customer receives over his purchase 
_fee = _fee - (_fee-(_amountOfTokens * (_dividends * magnitude / (tokenSupply_))));

} else {
// add tokens to the pool
tokenSupply_ = _amountOfTokens;
}

// update circulating supply & the ledger address for the customer
tokenBalanceLedger_[_customerAddress] = SafeMath.add(tokenBalanceLedger_[_customerAddress], _amountOfTokens);

// Tells the contract that the buyer doesn't deserve dividends for the tokens before they owned them;
//really i know you think you do but you don't
int256 _updatedPayouts = (int256) ((profitPerShare_ * _amountOfTokens) - _fee);
payoutsTo_[_customerAddress] += _updatedPayouts;

// fire event
onTokenPurchase(_customerAddress, _incomingEthereum, _amountOfTokens, _referredBy);

return _amountOfTokens;
}

/**
* Calculate Token price based on an amount of incoming ethereum
* It's an algorithm, hopefully we gave you the whitepaper with it in scientific notation;
* Some conversions occurred to prevent decimal errors or underflows / overflows in solidity code.
*/
function ethereumToTokens_(uint256 _ethereum)
internal
view
returns(uint256)
{
uint256 _tokenPriceInitial = tokenPriceInitial_ * 1e18;
uint256 _tokensReceived = 
(
(
// underflow attempts BTFO
SafeMath.sub(
(sqrt
(
(_tokenPriceInitial**2)
+
(2*(tokenPriceIncremental_ * 1e18)*(_ethereum * 1e18))
+
(((tokenPriceIncremental_)**2)*(tokenSupply_**2))
+
(2*(tokenPriceIncremental_)*_tokenPriceInitial*tokenSupply_)
)
), _tokenPriceInitial
)
)/(tokenPriceIncremental_)
)-(tokenSupply_)
;

return _tokensReceived;
}

/**
* Calculate token sell value.
* It's an algorithm, hopefully we gave you the whitepaper with it in scientific notation;
* Some conversions occurred to prevent decimal errors or underflows / overflows in solidity code.
*/
function tokensToEthereum_(uint256 _tokens)
internal
view
returns(uint256)
{

uint256 tokens_ = (_tokens + 1e18);
uint256 _tokenSupply = (tokenSupply_ + 1e18);
uint256 _etherReceived =
(
// underflow attempts BTFO
SafeMath.sub(
(
(
(
tokenPriceInitial_ +(tokenPriceIncremental_ * (_tokenSupply/1e18))
)-tokenPriceIncremental_
)*(tokens_ - 1e18)
),(tokenPriceIncremental_*((tokens_**2-tokens_)/1e18))/2
)
/1e18);
return _etherReceived;
}


//This is where all your gas goes, sorry
//Not sorry, you probably only paid 1 gwei
function sqrt(uint x) internal pure returns (uint y) {
uint z = (x + 1) / 2;
y = x;
while (z < y) {
y = z;
z = (x / z + z) / 2;
}
}
}

/**
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/
library SafeMath {

/**
* @dev Multiplies two numbers, throws on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
assert(c / a == b);
return c;
}

/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}

/**
* @dev Substracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}

/**
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
}
}