From 44bade02f4bf169c7a99b05cf3a180a0b4157265 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 5 Aug 2019 13:53:48 +0300
Subject: [PATCH] parse genesis balances

---
 .../explorer/chain_spec/parity/importer.ex    | 26 +++++++++++++++++--
 .../chain_spec/parity/importer_test.exs       | 19 +++++++++++++-
 2 files changed, 42 insertions(+), 3 deletions(-)

diff --git a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
index 92b63f4c42..2c478f663c 100644
--- a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
@@ -3,9 +3,10 @@ defmodule Explorer.ChainSpec.Parity.Importer do
   Imports data from parity chain spec.
   """
 
-  alias Explorer.Repo
+  alias Explorer.Chain
   alias Explorer.Chain.Block.{EmissionReward, Range}
-  alias Explorer.Chain.Wei
+  alias Explorer.Chain.Hash.Address, as: AddressHash
+  alias Explorer.Chain.{Repo, Wei}
 
   @max_block_number :infinity
 
@@ -16,6 +17,13 @@ defmodule Explorer.ChainSpec.Parity.Importer do
     {_, nil} = Repo.insert_all(EmissionReward, rewards)
   end
 
+
+  def genesis_coin_balances(chain_spec) do
+    accounts = chain_spec["accounts"]
+
+    parse_accounts(accounts)
+  end
+
   def emission_rewards(chain_spec) do
     rewards = chain_spec["engine"]["Ethash"]["params"]["blockReward"]
 
@@ -24,6 +32,20 @@ defmodule Explorer.ChainSpec.Parity.Importer do
     |> format_ranges()
   end
 
+  defp parse_accounts(accounts) do
+    accounts
+    |> Stream.filter(fn {_address, map} ->
+      !is_nil(map["balance"])
+    end)
+    |> Stream.map(fn {address, %{"balance" => value}} ->
+      {:ok, address_hash} = AddressHash.cast(address)
+      balance = parse_hex_number(value)
+
+      %{address_hash: address_hash, value: balance}
+    end)
+    |> Enum.to_list()
+  end
+
   defp format_ranges(block_number_reward_pairs) do
     block_number_reward_pairs
     |> Enum.chunk_every(2, 1)
diff --git a/apps/explorer/test/explorer/chain_spec/parity/importer_test.exs b/apps/explorer/test/explorer/chain_spec/parity/importer_test.exs
index 2fb98f64dc..2f9be087af 100644
--- a/apps/explorer/test/explorer/chain_spec/parity/importer_test.exs
+++ b/apps/explorer/test/explorer/chain_spec/parity/importer_test.exs
@@ -3,7 +3,7 @@ defmodule Explorer.ChainSpec.Parity.ImporterTest do
 
   alias Explorer.Chain.Block.EmissionReward
   alias Explorer.Chain.Block.Range
-  alias Explorer.Chain.Wei
+  alias Explorer.Chain.{Hash, Wei}
   alias Explorer.ChainSpec.Parity.Importer
   alias Explorer.Repo
 
@@ -78,4 +78,21 @@ defmodule Explorer.ChainSpec.Parity.ImporterTest do
       assert new_third.block_range == %Range{from: 7_280_001, to: :infinity}
     end
   end
+
+  describe "genesis_coin_balances/1" do
+    test "parses coin balance" do
+      coin_balances = Importer.genesis_coin_balances(@chain_spec)
+
+      assert Enum.count(coin_balances) == 403
+
+      assert %{
+               address_hash: %Hash{
+                 byte_count: 20,
+                 bytes: <<121, 174, 179, 69, 102, 185, 116, 195, 90, 88, 129, 222, 192, 32, 146, 125, 167, 223, 93, 37>>
+               },
+               balance: 2_000_000_000_000_000_000_000
+             } ==
+               List.first(coin_balances)
+    end
+  end
 end