Added milestone based pricing.

README.rst

@@ -50,7 +50,6 @@ Features and design goals
 
 * **Auditable**: Our tool chain supports `verifiable EtherScan.io contract builds <http://ico.readthedocs.io/en/latest/verification.html>`_
 
-
 * **Reusable**: The contract code is modularized and reusable across different projects, all variables are parametrized and there are no hardcoded values or magic numbers
 
 * **Refund**: Built-in refund and minimum funding goal protect investors

contracts/Crowdsale.sol

@@ -142,7 +142,7 @@ contract Crowdsale is Haltable {
   function invest(address receiver) inState(State.Funding) stopInEmergency payable public {
 
     uint weiAmount = msg.value;
-    uint tokenAmount = pricingStrategy.calculatePrice(weiAmount, weiRaised, tokensSold);
+    uint tokenAmount = pricingStrategy.calculatePrice(weiAmount, weiRaised, tokensSold, msg.sender);
 
     if(tokenAmount == 0) {
       // Dust transaction

contracts/FlatPricing.sol

@@ -7,6 +7,7 @@ import "./PricingStrategy.sol";
  */
 contract FlatPricing is PricingStrategy {
 
+  /* How many weis one token costs */
   uint public tokenPrice;
 
   function FlatPricing(uint _tokenPrice) {
@@ -18,7 +19,7 @@ contract FlatPricing is PricingStrategy {
    *
    * @param  {uint amount} Buy-in value in wei.
    */
-  function calculatePrice(uint value, uint tokensSold, uint weiRaised) public constant returns (uint) {
+  function calculatePrice(uint value, uint tokensSold, uint weiRaised, address msgSender) public constant returns (uint) {
     return value / tokenPrice;
   }
 

contracts/MilestonePricing.sol

@@ -0,0 +1,116 @@
+pragma solidity ^0.4.6;
+
+import "./PricingStrategy.sol";
+
+
+/**
+ * Time milestone based pricing with special support for pre-ico deals.
+ */
+contract MilestonePricing is PricingStrategy {
+
+  uint public constant MAX_MILESTONE = 10;
+
+  // This is our PresaleFundCollector contract
+  address public preicoContractAddress;
+
+  // Price for presale investors weis per toke
+  uint public preicoPrice;
+
+  /**
+  * Define pricing schedule using milestones.
+  */
+  struct Milestone {
+
+      // UNIX timestamp when this milestone kicks in
+      uint time;
+
+      // How many tokens per satoshi you will get after this milestone has been passed
+      uint price;
+  }
+
+  // Store milestones in a fixed array, so that it can be seen in a blockchain explorer
+  // Milestone 0 is always (0, 0)
+  // (TODO: change this when we confirm dynamic arrays are explorable)
+  Milestone[10] public milestones;
+
+  // How many active milestones we have
+  uint public milestoneCount;
+
+  /**
+   * @param _preicoContractAddress PresaleFundCollector address
+   * @param _preicoPrice How many weis one token cost for pre-ico investors
+   * @param _milestones uint[] miletones Pairs of (time, price)
+   */
+  function MilestonePricing(address _preicoContractAddress, uint _preicoPrice, uint[] _milestones) {
+
+    preicoContractAddress = _preicoContractAddress;
+    preicoPrice = _preicoPrice;
+
+    // Need to have tuples, length check
+    if(_milestones.length % 2 == 1 || _milestones.length >= MAX_MILESTONE) {
+      throw;
+    }
+
+    milestoneCount = _milestones.length / 2;
+
+    for(uint i=0; i<_milestones.length/2; i++) {
+      milestones[i].time = _milestones[i*2];
+      milestones[i].price = _milestones[i*2+1];
+    }
+  }
+
+  /**
+   * Iterate through milestones.
+   *
+   * You reach end of milestones when price = 0
+   *
+   * @return tuple (time, price)
+   */
+  function getMilestone(uint n) public constant returns (uint, uint) {
+     return (milestones[n].time, milestones[n].price);
+  }
+
+  /**
+   * Get the current milestone or bail out if we are not in the milestone periods.
+   *
+   * @return {[type]} [description]
+   */
+  function getCurrentMilestone() private constant returns (Milestone) {
+    uint i;
+    uint price;
+
+    for(i=0; i<milestones.length; i++) {
+      if(now < milestones[i].time) {
+        return milestones[i-1];
+      }
+    }
+  }
+
+  /**
+   * Get the current price.
+   *
+   * @return The current price or 0 if we are outside milestone period
+   */
+  function getCurrentPrice() public constant returns (uint result) {
+    return getCurrentMilestone().price;
+  }
+
+  /**
+   * Calculate the current price for buy in amount.
+   */
+  function calculatePrice(uint value, uint tokensSold, uint weiRaised, address msgSender) public constant returns (uint) {
+
+    // This investor is coming through pre-ico
+    if(msgSender == preicoContractAddress) {
+      return value / preicoPrice;
+    }
+
+    uint price = getCurrentPrice();
+    return value / price;
+  }
+
+  function() payable {
+    throw; // No money on this contract
+  }
+
+}

contracts/PricingStrategy.sol

@@ -8,5 +8,5 @@ contract PricingStrategy {
   /**
    * When somebody tries to buy tokens for X eth, calculate how many tokens they get.
    */
-  function calculatePrice(uint value, uint tokensSold, uint weiRaised) public constant returns (uint tokenAmount);
+  function calculatePrice(uint value, uint tokensSold, uint weiRaised, address msgSender) public constant returns (uint tokenAmount);
 }

contracts/Wallet.sol

@@ -1,3 +1,5 @@
+pragma solidity ^0.4.8;
+
 /**
  * This is a multisig wallet based on Gav's original implementation, daily withdraw limits removed.
  *

ico/tests/conftest.py

@@ -26,3 +26,4 @@ def nice_list_pytest_itemcollected(item):
 from ico.tests.fixtures.flatprice import *  # noqa
 from ico.tests.fixtures.releasable import *  # noqa
 from ico.tests.fixtures.finalize import *  # noqa
+from ico.tests.fixtures.presale import *  # noqa

ico/tests/contracts/test_milestone_pricing.py

@@ -0,0 +1,166 @@
+"""Milestone based pricing"""
+import datetime
+
+import pytest
+from eth_utils import to_wei
+from ethereum.tester import TransactionFailed
+from web3.contract import Contract
+
+
+from ico.tests.utils import time_travel
+
+
+@pytest.fixture
+def presale_fund_collector(chain, presale_freeze_ends_at, team_multisig) -> Contract:
+    """In actual ICO, the price is doubled (for testing purposes)."""
+
+    args = [
+        team_multisig,
+        presale_freeze_ends_at,
+        to_wei("50", "ether"),  # Minimum presale buy in is 50 ethers
+
+    ]
+    tx = {
+        "from": team_multisig,
+    }
+    presale_fund_collector, hash = chain.provider.deploy_contract('PresaleFundCollector', deploy_args=args, deploy_transaction=tx)
+    return presale_fund_collector
+
+
+@pytest.fixture
+def start_time() -> int:
+    return int((datetime.datetime(2017, 4, 15, 16, 00) - datetime.datetime(1970, 1, 1)).total_seconds())
+
+
+@pytest.fixture
+def token(uncapped_token) -> int:
+    """Token contract used in milestone tests"""
+    return uncapped_token
+
+
+@pytest.fixture
+def milestone_pricing(chain, presale_fund_collector, start_time):
+
+    week = 24*3600 * 7
+
+    args = [
+        presale_fund_collector.address,
+        to_wei("0.05", "ether"),
+        [
+            start_time + 0, to_wei("0.10", "ether"),
+            start_time + week*1, to_wei("0.12", "ether"),
+            start_time + week*2, to_wei("0.13", "ether"),
+            start_time + week*4, to_wei("0.13", "ether"),
+        ],
+    ]
+
+    tx = {
+        "gas": 4000000
+    }
+    contract, hash = chain.provider.deploy_contract('MilestonePricing', deploy_args=args, deploy_transaction=tx)
+    return contract
+
+
+@pytest.fixture
+def milestone_ico(chain, beneficiary, team_multisig, start_time, milestone_pricing, preico_cap, preico_funding_goal, token, presale_fund_collector) -> Contract:
+    """Create a crowdsale contract that uses milestone based pricing."""
+
+    ends_at = start_time + 4*24*3600
+
+    args = [
+        token.address,
+        milestone_pricing.address,
+        team_multisig,
+        beneficiary,
+        start_time,
+        ends_at,
+        0,
+    ]
+
+    tx = {
+        "from": team_multisig,
+    }
+
+    contract, hash = chain.provider.deploy_contract('UncappedCrowdsale', deploy_args=args, deploy_transaction=tx)
+
+    assert contract.call().owner() == team_multisig
+    assert not token.call().released()
+
+    # Allow pre-ico contract to do mint()
+    token.transact({"from": team_multisig}).setMintAgent(contract.address, True)
+    assert token.call().mintAgents(contract.address) == True
+
+    return contract
+
+
+def test_milestone_getter(chain, milestone_pricing, start_time):
+    """Milestone data is exposed to the world."""
+
+    time, price = milestone_pricing.call().getMilestone(0)
+    assert time == 1492272000
+    assert price == 100000000000000000
+
+
+def test_milestone_prices(chain, milestone_pricing, start_time, customer):
+    """We get correct milestone prices for different dates."""
+
+    time_travel(chain, start_time - 1)
+    with pytest.raises(TransactionFailed):
+        # Div by zero, crowdsale has not begin yet
+        assert milestone_pricing.call().getCurrentPrice()
+
+    time_travel(chain, start_time)
+    assert milestone_pricing.call().getCurrentPrice() == to_wei("0.10", "ether")
+
+    time_travel(chain, start_time + 1)
+    assert milestone_pricing.call().getCurrentPrice() == to_wei("0.10", "ether")
+
+    # 1 week forward
+    time_travel(chain, int((datetime.datetime(2017, 4, 22, 16, 0) - datetime.datetime(1970, 1, 1)).total_seconds()))
+    assert milestone_pricing.call().getCurrentPrice() == to_wei("0.12", "ether")
+
+    # 2 week forward
+    time_travel(chain, int((datetime.datetime(2017, 4, 29, 16, 0) - datetime.datetime(1970, 1, 1)).total_seconds()))
+    assert milestone_pricing.call().getCurrentPrice() == to_wei("0.13", "ether")
+
+    # See that we divide price correctly
+    assert milestone_pricing.call().calculatePrice(
+        to_wei("0.26", "ether"),
+        0,
+        0,
+        customer
+    ) == 2
+
+
+def test_milestone_calculate_preico_price(chain, milestone_pricing, start_time, presale_fund_collector):
+    """Preico contributors get their special price."""
+
+    # 1 week forward
+    time_travel(chain, int((datetime.datetime(2017, 4, 22, 16, 0) - datetime.datetime(1970, 1, 1)).total_seconds()))
+
+    # Pre-ico address always buys at the fixed price
+    assert milestone_pricing.call().calculatePrice(
+        to_wei("0.05", "ether"),
+        0,
+        0,
+        presale_fund_collector.address
+    ) == 1
+
+
+def test_presale_move_to_milestone_crowdsale(chain, presale_fund_collector, milestone_ico, token, start_time, team_multisig, customer, customer_2):
+    """When pre-ico contract funds are moved to the crowdsale, the pre-sale investors gets tokens with a preferred price and not the current milestone price."""
+
+    value = to_wei(50, "ether")
+    presale_fund_collector.transact({"from": customer, "value": value}).invest()
+
+    # ICO begins, Link presale to an actual ICO
+    presale_fund_collector.transact({"from": team_multisig}).setCrowdsale(milestone_ico.address)
+    time_travel(chain, start_time)
+
+    # Load funds to ICO
+    presale_fund_collector.transact().parcipateCrowdsaleAll()
+
+    # Tokens received, paid by preico price
+    milestone_ico.call().investedAmountOf(customer) == to_wei(50, "ether")
+    token.call().balanceOf(customer) == 50 / 0.050
+

ico/tests/contracts/test_presale.py

@@ -11,34 +11,6 @@
 from ico.utils import get_constructor_arguments
 
 
-@pytest.fixture
-def presale_freeze_ends_at() -> int:
-    """How long presale funds stay frozen until refund."""
-    return int(datetime.datetime(2017, 1, 1).timestamp())
-
-
-@pytest.fixture
-def presale_fund_collector(chain, presale_freeze_ends_at, team_multisig) -> Contract:
-    """In actual ICO, the price is doubled (for testing purposes)."""
-    args = [
-        team_multisig,
-        presale_freeze_ends_at,
-        to_wei(1, "ether")
-    ]
-    tx = {
-        "from": team_multisig,
-    }
-    presale_fund_collector, hash = chain.provider.deploy_contract('PresaleFundCollector', deploy_args=args, deploy_transaction=tx)
-    return presale_fund_collector
-
-
-@pytest.fixture
-def presale_crowdsale(chain, presale_fund_collector, uncapped_flatprice, team_multisig):
-    """ICO associated with the presale where funds will be moved to a presale."""
-    presale_fund_collector.transact({"from": team_multisig}).setCrowdsale(uncapped_flatprice.address)
-    return uncapped_flatprice
-
-
 def test_invest_presale(presale_fund_collector, customer, presale_freeze_ends_at):
     """Customer can invest into a presale."""
     value = to_wei(1, "ether")

ico/tests/contracts/test_two_stage.py

@@ -128,7 +128,7 @@ def test_buy_both_stages(chain: TestRPCChain, preico: Contract, actual_ico: Cont
 
     # First buy tokens when pre-ICO is open
     first_buy = to_wei(100000, "ether")
-    first_batch = flat_pricing.call().calculatePrice(first_buy, 0, 0)
+    first_batch = flat_pricing.call().calculatePrice(first_buy, 0, 0, customer)
     time_travel(chain, preico_starts_at + 1)
     assert preico.call().getState() == CrowdsaleState.Funding
     assert actual_ico.call().getState() == CrowdsaleState.PreFunding
@@ -144,7 +144,7 @@ def test_buy_both_stages(chain: TestRPCChain, preico: Contract, actual_ico: Cont
     time_travel(chain, actual_ico_starts_at + 1)
     assert actual_ico.call().getState() == CrowdsaleState.Funding
     second_buy = to_wei(2, "ether")
-    second_batch = final_pricing.call().calculatePrice(second_buy, 0, 0)
+    second_batch = final_pricing.call().calculatePrice(second_buy, 0, 0, customer)
     actual_ico.transact({"from": customer, "value": second_buy}).buy()
 
     # Close the actual ICO and check tokens are transferable

ico/tests/contracts/test_uncapped_flatprice.py

@@ -186,7 +186,7 @@ def test_buy_reach_goal(chain: TestRPCChain, flat_pricing, uncapped_flatprice: C
     wei_value = preico_funding_goal
 
     # Check that we don't have issues with our pricing
-    assert flat_pricing.call().calculatePrice(wei_value, 0, 0) > 0
+    assert flat_pricing.call().calculatePrice(wei_value, 0, 0, customer) > 0
 
     uncapped_flatprice.transact({"from": customer, "value": wei_value}).buy()