Contract Name:
SubscriptionsMinter
Contract Source Code:
File 1 of 1 : SubscriptionsMinter
pragma solidity 0.5.0;
contract PauserRole {
using Roles for Roles.Role;
event PauserAdded(address indexed account);
event PauserRemoved(address indexed account);
Roles.Role private _pausers;
constructor () internal {
_addPauser(msg.sender);
}
modifier onlyPauser() {
require(isPauser(msg.sender), "PauserRole: caller does not have the Pauser role");
_;
}
function isPauser(address account) public view returns (bool) {
return _pausers.has(account);
}
function addPauser(address account) public onlyPauser {
_addPauser(account);
}
function renouncePauser() public {
_removePauser(msg.sender);
}
function _addPauser(address account) internal {
_pausers.add(account);
emit PauserAdded(account);
}
function _removePauser(address account) internal {
_pausers.remove(account);
emit PauserRemoved(account);
}
}
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, "SafeMath: subtraction overflow");
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0, "SafeMath: modulo by zero");
return a % b;
}
}
/**
* @title Finance interface.
* @dev Copied from https://github.com/aragon/aragon-apps/blob/master/apps/finance/contracts/Finance.sol#L198 .
*/
contract Finance {
/**
* @notice Deposit Some token in the DAO
* @dev Deposit for approved ERC20 tokens or ETH
* @param _token Address of deposited token
* @param _amount Amount of tokens sent
* @param _reference Reason for payment
*/
function deposit(address _token, uint256 _amount, string calldata _reference) external payable;
}
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be aplied to your functions to restrict their use to
* the owner.
*/
contract Ownable {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor () internal {
_owner = msg.sender;
emit OwnershipTransferred(address(0), _owner);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(isOwner(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Returns true if the caller is the current owner.
*/
function isOwner() public view returns (bool) {
return msg.sender == _owner;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* > Note: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public onlyOwner {
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
*/
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0), "Ownable: new owner is the zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
/**
* @dev Interface of the ERC20 standard as defined in the EIP. Does not include
* the optional functions; to access them see `ERC20Detailed`.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a `Transfer` event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through `transferFrom`. This is
* zero by default.
*
* This value changes when `approve` or `transferFrom` are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* > 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
*
* Emits an `Approval` event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a `Transfer` event.
*/
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to `approve`. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
/**
* @dev Implementation of the `IERC20` interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using `_mint`.
* For a generic mechanism see `ERC20Mintable`.
*
* *For a detailed writeup see our guide [How to implement supply
* mechanisms](https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226).*
*
* We have followed general OpenZeppelin guidelines: functions revert instead
* of returning `false` on failure. This behavior is nonetheless conventional
* and does not conflict with the expectations of ERC20 applications.
*
* Additionally, an `Approval` event is emitted on calls to `transferFrom`.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard `decreaseAllowance` and `increaseAllowance`
* functions have been added to mitigate the well-known issues around setting
* allowances. See `IERC20.approve`.
*/
contract ERC20 is IERC20 {
using SafeMath for uint256;
mapping (address => uint256) private _balances;
mapping (address => mapping (address => uint256)) private _allowances;
uint256 private _totalSupply;
/**
* @dev See `IERC20.totalSupply`.
*/
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
/**
* @dev See `IERC20.balanceOf`.
*/
function balanceOf(address account) public view returns (uint256) {
return _balances[account];
}
/**
* @dev See `IERC20.transfer`.
*
* Requirements:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount) public returns (bool) {
_transfer(msg.sender, recipient, amount);
return true;
}
/**
* @dev See `IERC20.allowance`.
*/
function allowance(address owner, address spender) public view returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See `IERC20.approve`.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 value) public returns (bool) {
_approve(msg.sender, spender, value);
return true;
}
/**
* @dev See `IERC20.transferFrom`.
*
* Emits an `Approval` event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of `ERC20`;
*
* Requirements:
* - `sender` and `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `value`.
* - the caller must have allowance for `sender`'s tokens of at least
* `amount`.
*/
function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount));
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to `approve` that can be used as a mitigation for
* problems described in `IERC20.approve`.
*
* Emits an `Approval` event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
_approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to `approve` that can be used as a mitigation for
* problems described in `IERC20.approve`.
*
* Emits an `Approval` event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
_approve(msg.sender, spender, _allowances[msg.sender][spender].sub(subtractedValue));
return true;
}
/**
* @dev Moves tokens `amount` from `sender` to `recipient`.
*
* This is internal function is equivalent to `transfer`, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a `Transfer` event.
*
* Requirements:
*
* - `sender` cannot be the zero address.
* - `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
*/
function _transfer(address sender, address recipient, uint256 amount) internal {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_balances[sender] = _balances[sender].sub(amount);
_balances[recipient] = _balances[recipient].add(amount);
emit Transfer(sender, recipient, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a `Transfer` event with `from` set to the zero address.
*
* Requirements
*
* - `to` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal {
require(account != address(0), "ERC20: mint to the zero address");
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
/**
* @dev Destoys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a `Transfer` event with `to` set to the zero address.
*
* Requirements
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 value) internal {
require(account != address(0), "ERC20: burn from the zero address");
_totalSupply = _totalSupply.sub(value);
_balances[account] = _balances[account].sub(value);
emit Transfer(account, address(0), value);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
*
* This is internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an `Approval` event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/
function _approve(address owner, address spender, uint256 value) internal {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = value;
emit Approval(owner, spender, value);
}
/**
* @dev Destoys `amount` tokens from `account`.`amount` is then deducted
* from the caller's allowance.
*
* See `_burn` and `_approve`.
*/
function _burnFrom(address account, uint256 amount) internal {
_burn(account, amount);
_approve(account, msg.sender, _allowances[account][msg.sender].sub(amount));
}
}
/**
* @dev Collection of functions related to the address type,
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* This test is non-exhaustive, and there may be false-negatives: during the
* execution of a contract's constructor, its address will be reported as
* not containing a contract.
*
* > It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*/
function isContract(address account) internal view returns (bool) {
// This method relies in extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
}
contract FinanceManager is Ownable {
using Address for address;
using SafeMath for uint256;
Finance public finance;
string private constant APPROVE_ERROR = "Approve error.";
string private constant RECLAIM_MESSAGE = "Reclaiming tokens sent by mistake.";
string private constant IS_NOT_CONTRACT = "Address doesn't belong to a smart contract.";
string private constant ZERO_BALANCE = "There are no tokens of this type to be reclaimed.";
event ReclaimedTokens(address tokenAddr, uint256 amount);
event FinanceSet(address financeAddr);
/**
* @notice Set the DAO finance app address where deposited or reclaimed tokens will go.
* @param _finance The DAO's finance app with a deposit() function.
*/
function setFinance(Finance _finance)
external
onlyOwner
{
require(address(_finance).isContract(), IS_NOT_CONTRACT);
finance = _finance;
emit FinanceSet(address(_finance));
}
/**
* @notice Reclaim tokens of the specified type sent to the smart contract.
* @dev Reclaim the specified type of ERC20 tokens sent to the smart contract.
* Tokens will be deposited into the finance app set with setFinance().
* @param token The token contract.
*/
function reclaimTokens(ERC20 token)
external
onlyOwner
{
require(address(token).isContract(), IS_NOT_CONTRACT);
uint256 balance = token.balanceOf(address(this));
require(0 < balance, ZERO_BALANCE);
deposit(token, balance, RECLAIM_MESSAGE);
emit ReclaimedTokens(address(token), balance);
}
/**
* @dev Deposit the specified type of ERC20 tokens using the finance app set
* with setFinance().
* @param token The token contract.
* @param amount Number of tokens to deposit.
* @param _reference Reason for the deposit.
*/
function deposit(ERC20 token, uint256 amount, string memory _reference)
internal
{
require(token.approve(address(finance), amount), APPROVE_ERROR);
finance.deposit(address(token), amount, _reference);
}
}
/**
* @title Roles
* @dev Library for managing addresses assigned to a Role.
*/
library Roles {
struct Role {
mapping (address => bool) bearer;
}
/**
* @dev Give an account access to this role.
*/
function add(Role storage role, address account) internal {
require(!has(role, account), "Roles: account already has role");
role.bearer[account] = true;
}
/**
* @dev Remove an account's access to this role.
*/
function remove(Role storage role, address account) internal {
require(has(role, account), "Roles: account does not have role");
role.bearer[account] = false;
}
/**
* @dev Check if an account has this role.
* @return bool
*/
function has(Role storage role, address account) internal view returns (bool) {
require(account != address(0), "Roles: account is the zero address");
return role.bearer[account];
}
}
contract MinterRole {
using Roles for Roles.Role;
event MinterAdded(address indexed account);
event MinterRemoved(address indexed account);
Roles.Role private _minters;
constructor () internal {
_addMinter(msg.sender);
}
modifier onlyMinter() {
require(isMinter(msg.sender), "MinterRole: caller does not have the Minter role");
_;
}
function isMinter(address account) public view returns (bool) {
return _minters.has(account);
}
function addMinter(address account) public onlyMinter {
_addMinter(account);
}
function renounceMinter() public {
_removeMinter(msg.sender);
}
function _addMinter(address account) internal {
_minters.add(account);
emit MinterAdded(account);
}
function _removeMinter(address account) internal {
_minters.remove(account);
emit MinterRemoved(account);
}
}
/**
* @dev Contract module which allows children to implement an emergency stop
* mechanism that can be triggered by an authorized account.
*
* This module is used through inheritance. It will make available the
* modifiers `whenNotPaused` and `whenPaused`, which can be applied to
* the functions of your contract. Note that they will not be pausable by
* simply including this module, only once the modifiers are put in place.
*/
contract Pausable is PauserRole {
/**
* @dev Emitted when the pause is triggered by a pauser (`account`).
*/
event Paused(address account);
/**
* @dev Emitted when the pause is lifted by a pauser (`account`).
*/
event Unpaused(address account);
bool private _paused;
/**
* @dev Initializes the contract in unpaused state. Assigns the Pauser role
* to the deployer.
*/
constructor () internal {
_paused = false;
}
/**
* @dev Returns true if the contract is paused, and false otherwise.
*/
function paused() public view returns (bool) {
return _paused;
}
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*/
modifier whenNotPaused() {
require(!_paused, "Pausable: paused");
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*/
modifier whenPaused() {
require(_paused, "Pausable: not paused");
_;
}
/**
* @dev Called by a pauser to pause, triggers stopped state.
*/
function pause() public onlyPauser whenNotPaused {
_paused = true;
emit Paused(msg.sender);
}
/**
* @dev Called by a pauser to unpause, returns to normal state.
*/
function unpause() public onlyPauser whenPaused {
_paused = false;
emit Unpaused(msg.sender);
}
}
/**
* @title Pausable token
* @dev ERC20 modified with pausable transfers.
*/
contract ERC20Pausable is ERC20, Pausable {
function transfer(address to, uint256 value) public whenNotPaused returns (bool) {
return super.transfer(to, value);
}
function transferFrom(address from, address to, uint256 value) public whenNotPaused returns (bool) {
return super.transferFrom(from, to, value);
}
function approve(address spender, uint256 value) public whenNotPaused returns (bool) {
return super.approve(spender, value);
}
function increaseAllowance(address spender, uint addedValue) public whenNotPaused returns (bool) {
return super.increaseAllowance(spender, addedValue);
}
function decreaseAllowance(address spender, uint subtractedValue) public whenNotPaused returns (bool) {
return super.decreaseAllowance(spender, subtractedValue);
}
}
/**
* @title Sponsorships contract
*/
contract Sponsorships is ERC20Pausable, MinterRole, FinanceManager {
string public constant name = "Sponsorships";
string public constant symbol = "Sp";
uint8 public constant decimals = 0;
string private constant INSUFFICIENT_BALANCE = "Insufficient balance";
string private constant INVALID_AMOUNT = "Amount must be greater than zero";
struct Account {
mapping (bytes32 => uint256) contexts;
}
mapping(address => Account) private accounts;
mapping(bytes32 => uint256) private contextsBalance;
event SponsorshipsAssigned(address account, bytes32 contextName, uint256 amount);
/**
* @notice Mint Sponsorships.
* @dev Mint Sponsorships.
* @param account The receiver's account.
* @param amount The number of Sponsorships.
*/
function mint(address account, uint256 amount)
public
onlyMinter
whenNotPaused
onlyPositive(amount)
returns (bool)
{
_mint(account, amount);
return true;
}
/**
* @notice Assign Sponsorships to the context.
* @dev Assign Sponsorships to the context.
* @param contextName The context's name.
* @param amount The number of Sponsorships.
*/
function assignContext(bytes32 contextName, uint256 amount)
external
whenNotPaused
onlyPositive(amount)
{
require(amount <= balanceOf(msg.sender), INSUFFICIENT_BALANCE);
accounts[msg.sender].contexts[contextName] = accounts[msg.sender].contexts[contextName].add(amount);
contextsBalance[contextName] = contextsBalance[contextName].add(amount);
_burn(msg.sender, amount);
emit SponsorshipsAssigned(msg.sender, contextName, amount);
}
/**
* @notice Returns the number of Sponsorships assigned to the context.
* @dev Returns the number of Sponsorships assigned to the context.
* @param contextName The context's name.
*/
function totalContextBalance(bytes32 contextName)
external
view
returns (uint256)
{
return contextsBalance[contextName];
}
/**
* @notice Returns the number of Sponsorships assigned by the account to the context.
* @dev Returns the number of Sponsorships assigned by the account to the context.
* @param account The assigner's address.
* @param contextName The context's name.
*/
function contextBalance(address account, bytes32 contextName)
external
view
returns (uint256)
{
return accounts[account].contexts[contextName];
}
/**
* @dev Throws if the number is not bigger than zero.
* @param number The number to validate.
*/
modifier onlyPositive(uint number) {
require(0 < number, INVALID_AMOUNT);
_;
}
}
/**
* @title Subscriptions contract
*/
contract Subscriptions is ERC20Pausable, MinterRole, FinanceManager {
string public constant name = "Subscriptions";
string public constant symbol = "Subs";
uint8 public constant decimals = 0;
string private constant ALL_SPONSORSHIPS_CLAIMED = "All Sponsorships claimed";
string private constant INVALID_AMOUNT = "Amount must be greater than zero";
struct Account {
uint256 received;
// Array to keep track of timestamps for the batches.
uint256[] timestamps;
// Batches mapped from timestamps to amounts.
mapping (uint256 => uint256) batches;
}
mapping(address => Account) private accounts;
event SubscriptionsActivated(address account, uint256 amount);
/**
* @notice Mint Subscriptions.
* @dev Mint Subscriptions.
* @param account The receiver's account address.
* @param amount The number of Subscriptions.
*/
function mint(address account, uint256 amount)
public
onlyMinter
whenNotPaused
onlyPositive(amount)
returns (bool)
{
_mint(account, amount);
return true;
}
/**
* @notice Activate Subscriptions.
* @dev Activate Subscriptions.
* @param amount The number of Subscriptions.
*/
function activate(uint256 amount)
public
whenNotPaused
onlyPositive(amount)
returns (bool)
{
uint256 timestamp = now;
accounts[msg.sender].timestamps.push(timestamp);
accounts[msg.sender].batches[timestamp] = amount;
_burn(msg.sender, amount);
emit SubscriptionsActivated(msg.sender, amount);
return true;
}
/**
* @notice Tells the minter how many Sponsorships the account holder can claim.
* @dev Tells the minter how many Sponsorships the account holder can claim so it can
* then mint them. Also increments the account's "received" counter to indicate the
* number of Sponsorships that have been claimed.
* @param account The claimer's account address.
* @return The number of Sponsorships the account holder can claim.
*/
function claim(address account)
external
onlyMinter
whenNotPaused
returns (uint256 amount)
{
uint256 claimableAmount = claimable(account);
require(0 < claimableAmount, ALL_SPONSORSHIPS_CLAIMED);
accounts[account].received = accounts[account].received.add(claimableAmount);
return claimableAmount;
}
/**
* @notice Computes the number of Sponsorships the account holder can claim.
* @dev Computes the number of Sponsorships the account holder can claim.
* @param account The claimer's account address.
* @return The number of Sponsorships the account holder can claim.
*/
function claimable(address account)
public
view
returns (uint256 amount)
{
// The number of Sponsorships produced by all of this account's batches.
uint256 allProduced;
// Loop through all the batches.
for (uint i = 0; i < accounts[account].timestamps.length; i++) {
uint256 timestamp = accounts[account].timestamps[i];
// The number of Subscriptions purchased in the batch that matches the timestamp.
uint256 subsInBatch = accounts[account].batches[timestamp];
// "months" is the number of whole 30-day periods since the batch was purchased (plus one).
// We add one because we want each Subscription to start with one claimable sponsorship immediately.
uint256 months = ((now - timestamp) / (30*24*3600)) + 1;
// Subscriptions end after 71 30-day periods (a little less than 6 years).
if (72 < months) {
months = 72;
}
uint256 _years = months / 12;
// One Subscription produces 252 Sponsorships in total.
uint256 producedPerSub = 6 * _years * (_years + 1) + (months % 12) * (_years + 1);
allProduced += (producedPerSub * subsInBatch);
}
uint256 claimableAmount = allProduced - accounts[account].received;
return claimableAmount;
}
/**
* @dev Throws if the number is not bigger than zero
* @param number The number to validate
*/
modifier onlyPositive(uint number) {
require(0 < number, INVALID_AMOUNT);
_;
}
}
/**
* @title Subscriptions minter contract
*/
contract SubscriptionsMinter is FinanceManager {
Subscriptions internal subs;
Sponsorships internal sp;
uint256 public totalSold;
ERC20 public purchaseToken;
// This needs to match the total number of Subscriptions in all steps.
uint256 public constant CAP = 900000;
string private constant INSUFFICIENT_PAYMENT = "Insufficient payment";
string private constant MINT_ERROR = "Mint error";
string private constant TRANSFER_FROM_ERROR = "Purchase token transferFrom failed.";
string private constant FINANCE_MESSAGE = "Revenue of Subscriptions sale";
string private constant CAP_EXCEEDED = "Cap exceeded";
// The price of Subscriptions is a step function of the number of Subscriptions
// already sold.
struct Step {
uint256 border;
uint256 price;
}
// Each step of the price function is numbered, starting from zero.
mapping(uint8 => Step) private steps;
event SubscriptionsPurchased(address account, uint256 amount, uint256 price);
event SponsorshipsClaimed(address account, uint256 amount);
constructor(Sponsorships _sp, Subscriptions _subs, ERC20 _purchaseToken)
public
{
// Define the steps for the price of Subscriptions.
steps[0].border = 400000;
steps[0].price = 10**18;
steps[1].border = 900000;
steps[1].price = 2 * 10**18;
sp = _sp;
subs = _subs;
purchaseToken = _purchaseToken;
}
/**
* @notice Purchase Subscriptions.
* @dev Purchase Subscriptions.
*/
function purchase()
external
returns (bool success)
{
uint8 stepNumber;
require(totalSold < CAP, CAP_EXCEEDED);
uint256 allowance = purchaseToken.allowance(msg.sender, address(this));
if (totalSold < steps[0].border) {
stepNumber = 0;
}
else {
stepNumber = 1;
}
uint256 price = steps[stepNumber].price;
require(price <= allowance, INSUFFICIENT_PAYMENT);
uint256 availableSubs = steps[stepNumber].border.sub(totalSold);
uint256 subsAmount = allowance.div(price);
// Only sell the Subscriptions left in the current step. If the user wants to buy
// more Subscriptions from the next step, they will have to make another purchase.
if (availableSubs < subsAmount) {
subsAmount = availableSubs;
}
totalSold = totalSold.add(subsAmount);
uint256 purchaseTokenAmount = subsAmount.mul(price);
require(purchaseToken.transferFrom(msg.sender, address(this), purchaseTokenAmount), TRANSFER_FROM_ERROR);
deposit(purchaseToken, purchaseTokenAmount, FINANCE_MESSAGE);
require(subs.mint(msg.sender, subsAmount), MINT_ERROR);
emit SubscriptionsPurchased(msg.sender, subsAmount, price);
return true;
}
/**
* @notice Show the current price of one Subscription.
* @dev Show the current price of one Subscription.
*/
function price()
external
view
returns (uint256)
{
if (totalSold < steps[0].border) {
return steps[0].price;
}
return steps[1].price;
}
/**
* @notice claim Sponsorships.
* @dev claim Sponsorships.
*/
function claim()
external
returns (bool success)
{
// First, get the number of Sponsorships to mint from the Subscriptions contract.
// This will increment a "received" counter for the account. After this is done,
// the Subscriptions contract will consider these Sponsorships to actually have
// been received.
uint256 claimableAmount = subs.claim(msg.sender);
// Next tell the Sponsorships contract to actually mint the correct number of
// Sponsorships into the claimer's account address.
require(sp.mint(msg.sender, claimableAmount), MINT_ERROR);
emit SponsorshipsClaimed(msg.sender, claimableAmount);
return true;
}
/**
* @notice Disable purchases
* @dev Renounce minter
*/
function disablePurchases()
external
onlyOwner
{
subs.renounceMinter();
}
/**
* @notice Disable claims
* @dev Renounce minter
*/
function disableClaims()
external
onlyOwner
{
sp.renounceMinter();
}
}