Contract Name:
FlypCrowdsale
Contract Source Code:
File 1 of 1 : FlypCrowdsale
pragma solidity ^0.4.15;
/**
* @title ERC20Basic
* @dev Simpler version of ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/179
*/
contract ERC20Basic {
uint256 public totalSupply;
function balanceOf(address who) public constant returns (uint256);
function transfer(address to, uint256 value) public returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
}
/**
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/
library SafeMath {
function mul(uint256 a, uint256 b) internal constant returns (uint256) {
uint256 c = a * b;
assert(a == 0 || c / a == b);
return c;
}
function div(uint256 a, uint256 b) internal constant 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;
}
function sub(uint256 a, uint256 b) internal constant returns (uint256) {
assert(b <= a);
return a - b;
}
function add(uint256 a, uint256 b) internal constant returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
}
}
/**
* @title Basic token
* @dev Basic version of StandardToken, with no allowances.
*/
contract BasicToken is ERC20Basic {
using SafeMath for uint256;
mapping(address => uint256) balances;
/**
* @dev transfer token for a specified address
* @param _to The address to transfer to.
* @param _value The amount to be transferred.
*/
function transfer(address _to, uint256 _value) public returns (bool) {
require(_to != address(0));
// SafeMath.sub will throw if there is not enough balance.
balances[msg.sender] = balances[msg.sender].sub(_value);
balances[_to] = balances[_to].add(_value);
Transfer(msg.sender, _to, _value);
return true;
}
/**
* @dev Gets the balance of the specified address.
* @param _owner The address to query the the balance of.
* @return An uint256 representing the amount owned by the passed address.
*/
function balanceOf(address _owner) public constant returns (uint256 balance) {
return balances[_owner];
}
}
/**
* @title ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/20
*/
contract ERC20 is ERC20Basic {
function allowance(address owner, address spender) public constant returns (uint256);
function transferFrom(address from, address to, uint256 value) public returns (bool);
function approve(address spender, uint256 value) public returns (bool);
event Approval(address indexed owner, address indexed spender, uint256 value);
}
/**
* @title Standard ERC20 token
*
* @dev Implementation of the basic standard token.
* @dev https://github.com/ethereum/EIPs/issues/20
* @dev Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
*/
contract StandardToken is ERC20, BasicToken {
mapping (address => mapping (address => uint256)) allowed;
/**
* @dev Transfer tokens from one address to another
* @param _from address The address which you want to send tokens from
* @param _to address The address which you want to transfer to
* @param _value uint256 the amount of tokens to be transferred
*/
function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
require(_to != address(0));
uint256 _allowance = allowed[_from][msg.sender];
// Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
// require (_value <= _allowance);
balances[_from] = balances[_from].sub(_value);
balances[_to] = balances[_to].add(_value);
allowed[_from][msg.sender] = _allowance.sub(_value);
Transfer(_from, _to, _value);
return true;
}
/**
* @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
*
* Beware that changing an allowance with this method brings the risk that someone may use both the old
* and the new allowance by unfortunate transaction ordering. One possible solution to mitigate this
* race condition is to first reduce the spender's allowance to 0 and set the desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
* @param _spender The address which will spend the funds.
* @param _value The amount of tokens to be spent.
*/
function approve(address _spender, uint256 _value) public returns (bool) {
allowed[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
return true;
}
/**
* @dev Function to check the amount of tokens that an owner allowed to a spender.
* @param _owner address The address which owns the funds.
* @param _spender address The address which will spend the funds.
* @return A uint256 specifying the amount of tokens still available for the spender.
*/
function allowance(address _owner, address _spender) public constant returns (uint256 remaining) {
return allowed[_owner][_spender];
}
/**
* approve should be called when allowed[_spender] == 0. To increment
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
*/
function increaseApproval (address _spender, uint _addedValue)
returns (bool success) {
allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
return true;
}
function decreaseApproval (address _spender, uint _subtractedValue)
returns (bool success) {
uint oldValue = allowed[msg.sender][_spender];
if (_subtractedValue > oldValue) {
allowed[msg.sender][_spender] = 0;
} else {
allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
}
Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
return true;
}
}
/**
* @title Ownable
* @dev The Ownable contract has an owner address, and provides basic authorization control
* functions, this simplifies the implementation of "user permissions".
*/
contract Ownable {
address public owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
function Ownable() {
owner = msg.sender;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(msg.sender == owner);
_;
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferOwnership(address newOwner) onlyOwner public {
require(newOwner != address(0));
OwnershipTransferred(owner, newOwner);
owner = newOwner;
}
}
/**
* @title Mintable token
* @dev Simple ERC20 Token example, with mintable token creation
* @dev Issue: * https://github.com/OpenZeppelin/zeppelin-solidity/issues/120
* Based on code by TokenMarketNet: https://github.com/TokenMarketNet/ico/blob/master/contracts/MintableToken.sol
*/
contract MintableToken is StandardToken, Ownable {
event Mint(address indexed to, uint256 amount);
event MintFinished();
bool public mintingFinished = false;
modifier canMint() {
require(!mintingFinished);
_;
}
/**
* @dev Function to mint tokens
* @param _to The address that will receive the minted tokens.
* @param _amount The amount of tokens to mint.
* @return A boolean that indicates if the operation was successful.
*/
function mint(address _to, uint256 _amount) onlyOwner canMint public returns (bool) {
totalSupply = totalSupply.add(_amount);
balances[_to] = balances[_to].add(_amount);
Mint(_to, _amount);
Transfer(0x0, _to, _amount);
return true;
}
/**
* @dev Function to stop minting new tokens.
* @return True if the operation was successful.
*/
function finishMinting() onlyOwner public returns (bool) {
mintingFinished = true;
MintFinished();
return true;
}
}
/**
* @title Crowdsale
* @dev Crowdsale is a base contract for managing a token crowdsale.
* Crowdsales have a start and end timestamps, where investors can make
* token purchases and the crowdsale will assign them tokens based
* on a token per ETH rate. Funds collected are forwarded to a wallet
* as they arrive.
*/
contract Crowdsale {
using SafeMath for uint256;
// The token being sold
MintableToken public token;
// start and end timestamps where investments are allowed (both inclusive)
uint256 public startTime;
uint256 public endTime;
// address where funds are collected
address public wallet;
// how many token units a buyer gets per wei
uint256 public rate;
// amount of raised money in wei
uint256 public weiRaised;
/**
* event for token purchase logging
* @param purchaser who paid for the tokens
* @param beneficiary who got the tokens
* @param value weis paid for purchase
* @param amount amount of tokens purchased
*/
event TokenPurchase(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);
function Crowdsale(uint256 _startTime, uint256 _endTime, uint256 _rate, address _wallet) {
require(_startTime >= now);
require(_endTime >= _startTime);
require(_rate > 0);
require(_wallet != 0x0);
token = createTokenContract();
startTime = _startTime;
endTime = _endTime;
rate = _rate;
wallet = _wallet;
}
// creates the token to be sold.
// override this method to have crowdsale of a specific mintable token.
function createTokenContract() internal returns (MintableToken) {
return new MintableToken();
}
// fallback function can be used to buy tokens
function () payable {
buyTokens(msg.sender);
}
// low level token purchase function
function buyTokens(address beneficiary) public payable {
require(beneficiary != 0x0);
require(validPurchase());
uint256 weiAmount = msg.value;
// calculate token amount to be created
uint256 tokens = weiAmount.mul(rate);
// update state
weiRaised = weiRaised.add(weiAmount);
token.mint(beneficiary, tokens);
TokenPurchase(msg.sender, beneficiary, weiAmount, tokens);
forwardFunds();
}
// send ether to the fund collection wallet
// override to create custom fund forwarding mechanisms
function forwardFunds() internal {
wallet.transfer(msg.value);
}
// @return true if the transaction can buy tokens
function validPurchase() internal constant returns (bool) {
bool withinPeriod = now >= startTime && now <= endTime;
bool nonZeroPurchase = msg.value != 0;
return withinPeriod && nonZeroPurchase;
}
// @return true if crowdsale event has ended
function hasEnded() public constant returns (bool) {
return now > endTime;
}
}
/**
* @title FinalizableCrowdsale
* @dev Extension of Crowdsale where an owner can do extra work
* after finishing.
*/
contract FinalizableCrowdsale is Crowdsale, Ownable {
using SafeMath for uint256;
bool public isFinalized = false;
event Finalized();
/**
* @dev Must be called after crowdsale ends, to do some extra finalization
* work. Calls the contract's finalization function.
*/
function finalize() onlyOwner public {
require(!isFinalized);
require(hasEnded());
finalization();
Finalized();
isFinalized = true;
}
/**
* @dev Can be overridden to add finalization logic. The overriding function
* should call super.finalization() to ensure the chain of finalization is
* executed entirely.
*/
function finalization() internal {
}
}
/**
* @title FinalizableCrowdsale
* @dev Extension of Crowsdale where an owner can do extra work
* after finishing. By default, it will end token minting.
*/
contract MyFinalizableCrowdsale is FinalizableCrowdsale {
using SafeMath for uint256;
// address where funds are collected
address public tokenWallet;
event FinalTokens(uint256 _generated);
function MyFinalizableCrowdsale(address _tokenWallet) {
tokenWallet = _tokenWallet;
}
function generateFinalTokens(uint256 ratio) internal {
uint256 finalValue = token.totalSupply();
finalValue = finalValue.mul(ratio).div(1000);
token.mint(tokenWallet, finalValue);
FinalTokens(finalValue);
}
}
/**
* @title MultiCappedCrowdsale
* @dev Extension of Crowsdale with a soft cap and a hard cap.
* after finishing. By default, it will end token minting.
*/
contract MultiCappedCrowdsale is Crowdsale, Ownable {
using SafeMath for uint256;
uint256 public softCap;
uint256 public hardCap = 0;
bytes32 public hardCapHash;
uint256 public hardCapTime = 0;
uint256 public endBuffer;
event NotFinalized(bytes32 _a, bytes32 _b);
function MultiCappedCrowdsale(uint256 _softCap, bytes32 _hardCapHash, uint256 _endBuffer) {
require(_softCap > 0);
softCap = _softCap;
hardCapHash = _hardCapHash;
endBuffer = _endBuffer;
}
//
// Soft cap logic
//
// overriding Crowdsale#validPurchase to add extra cap logic
// @return true if investors can buy at the moment
function validPurchase() internal constant returns (bool) {
if (hardCap > 0) {
checkHardCap(weiRaised.add(msg.value));
}
return super.validPurchase();
}
//
// Hard cap logic
//
function hashHardCap(uint256 _hardCap, uint256 _key) internal constant returns (bytes32) {
return keccak256(_hardCap, _key);
}
function setHardCap(uint256 _hardCap, uint256 _key) external onlyOwner {
require(hardCap==0);
if (hardCapHash != hashHardCap(_hardCap, _key)) {
NotFinalized(hashHardCap(_hardCap, _key), hardCapHash);
return;
}
hardCap = _hardCap;
checkHardCap(weiRaised);
}
function checkHardCap(uint256 totalRaised) internal {
if (hardCapTime == 0 && totalRaised > hardCap) {
hardCapTime = block.timestamp;
endTime = block.timestamp+endBuffer;
}
}
}
/**
* @title LimitedTransferToken
* @dev LimitedTransferToken defines the generic interface and the implementation to limit token
* transferability for different events. It is intended to be used as a base class for other token
* contracts.
* LimitedTransferToken has been designed to allow for different limiting factors,
* this can be achieved by recursively calling super.transferableTokens() until the base class is
* hit. For example:
* function transferableTokens(address holder, uint64 time) constant public returns (uint256) {
* return min256(unlockedTokens, super.transferableTokens(holder, time));
* }
* A working example is VestedToken.sol:
* https://github.com/OpenZeppelin/zeppelin-solidity/blob/master/contracts/token/VestedToken.sol
*/
contract LimitedTransferToken is ERC20 {
/**
* @dev Checks whether it can transfer or otherwise throws.
*/
modifier canTransfer(address _sender, uint256 _value) {
require(_value <= transferableTokens(_sender, uint64(now)));
_;
}
/**
* @dev Checks modifier and allows transfer if tokens are not locked.
* @param _to The address that will receive the tokens.
* @param _value The amount of tokens to be transferred.
*/
function transfer(address _to, uint256 _value) canTransfer(msg.sender, _value) public returns (bool) {
return super.transfer(_to, _value);
}
/**
* @dev Checks modifier and allows transfer if tokens are not locked.
* @param _from The address that will send the tokens.
* @param _to The address that will receive the tokens.
* @param _value The amount of tokens to be transferred.
*/
function transferFrom(address _from, address _to, uint256 _value) canTransfer(_from, _value) public returns (bool) {
return super.transferFrom(_from, _to, _value);
}
/**
* @dev Default transferable tokens function returns all tokens for a holder (no limit).
* @dev Overwriting transferableTokens(address holder, uint64 time) is the way to provide the
* specific logic for limiting token transferability for a holder over time.
*/
function transferableTokens(address holder, uint64 time) public constant returns (uint256) {
return balanceOf(holder);
}
}
/**
* @title FypToken
*/
contract FypToken is MintableToken, LimitedTransferToken {
string public constant name = "Flyp.me Token";
string public constant symbol = "FYP";
uint8 public constant decimals = 18;
bool public isTransferable = false;
function enableTransfers() onlyOwner {
isTransferable = true;
}
function transferableTokens(address holder, uint64 time) public constant returns (uint256) {
if (!isTransferable) {
return 0;
}
return super.transferableTokens(holder, time);
}
function finishMinting() onlyOwner public returns (bool) {
enableTransfers();
return super.finishMinting();
}
}
/**
* @title FlypCrowdsale
* @dev This is a sale with the following features:
* - erc20 based
* - Soft cap and hidden hard cap
* - When finished distributes percent to specific address based on whether the
* cap was reached.
* - Start and end times for the ico
* - Sends incoming eth to a specific address
*/
contract FlypCrowdsale is MyFinalizableCrowdsale, MultiCappedCrowdsale {
// how many token units a buyer gets per wei
uint256 public presaleRate;
uint256 public postSoftRate;
uint256 public postHardRate;
uint256 public presaleEndTime;
function FlypCrowdsale(uint256 _startTime, uint256 _endTime, uint256 _presaleEndTime, uint256 _rate, uint256 _rateDiff, uint256 _softCap, address _wallet, bytes32 _hardCapHash, address _tokenWallet, uint256 _endBuffer)
MultiCappedCrowdsale(_softCap, _hardCapHash, _endBuffer)
MyFinalizableCrowdsale(_tokenWallet)
Crowdsale(_startTime, _endTime, _rate, _wallet)
{
presaleRate = _rate+_rateDiff;
postSoftRate = _rate-_rateDiff;
postHardRate = _rate-(2*_rateDiff);
presaleEndTime = _presaleEndTime;
}
// Allows generating tokens for externally funded participants (other blockchains)
function pregenTokens(address beneficiary, uint256 weiAmount, uint256 tokenAmount) external onlyOwner {
require(beneficiary != 0x0);
// update state
weiRaised = weiRaised.add(weiAmount);
token.mint(beneficiary, tokenAmount);
TokenPurchase(msg.sender, beneficiary, weiAmount, tokenAmount);
}
// Overrides Crowdsale function
function buyTokens(address beneficiary) public payable {
require(beneficiary != 0x0);
require(validPurchase());
uint256 weiAmount = msg.value;
uint256 currentRate = rate;
if (block.timestamp < presaleEndTime) {
currentRate = presaleRate;
}
else if (hardCap > 0 && weiRaised > hardCap) {
currentRate = postHardRate;
}
else if (weiRaised > softCap) {
currentRate = postSoftRate;
}
// calculate token amount to be created
uint256 tokens = weiAmount.mul(currentRate);
// update state
weiRaised = weiRaised.add(weiAmount);
token.mint(beneficiary, tokens);
TokenPurchase(msg.sender, beneficiary, weiAmount, tokens);
forwardFunds();
}
// Overrides Crowdsale function
function createTokenContract() internal returns (MintableToken) {
return new FypToken();
}
// Overrides FinalizableCrowdsale function
function finalization() internal {
if (weiRaised < softCap) {
generateFinalTokens(1000);
} else if (weiRaised < hardCap) {
generateFinalTokens(666);
} else {
generateFinalTokens(428);
}
token.finishMinting();
super.finalization();
}
// Make sure no eth funds become stuck on contract
function withdraw(uint256 weiValue) onlyOwner {
wallet.transfer(weiValue);
}
}