From b2ea6562396f9610062834fce62d22aedab1778e Mon Sep 17 00:00:00 2001
From: ElFantasma <esteban.dimitroff@lambdaclass.com>
Date: Fri, 22 Sep 2023 13:21:20 -0300
Subject: [PATCH] Added support for simple arrays (#182)

* Added support for simple arrays

* Added support for complex types
---
 lib/starknet_explorer/calldata.ex             | 216 +++++++++++++-----
 .../live/transaction_live.ex                  |   2 +-
 lib/starknet_explorer_web/live/utils.ex       |  35 ++-
 3 files changed, 188 insertions(+), 65 deletions(-)

diff --git a/lib/starknet_explorer/calldata.ex b/lib/starknet_explorer/calldata.ex
index 6afbef9f..10f29867 100644
--- a/lib/starknet_explorer/calldata.ex
+++ b/lib/starknet_explorer/calldata.ex
@@ -20,8 +20,10 @@ defmodule StarknetExplorer.Calldata do
     Enum.map(
       calldata,
       fn call ->
-        input = get_input_data(block_id, call.address, call.selector, network)
-        Map.put(call, :call, as_fn_call(input, call.calldata))
+        functions_data = get_functions_data(block_id, call.address, network)
+        {function, structs} = get_input_data(functions_data, call.selector)
+
+        Map.put(call, :call, as_fn_call(function, call.calldata, structs))
       end
     )
   end
@@ -91,43 +93,98 @@ defmodule StarknetExplorer.Calldata do
     ("0x" <> Integer.to_string(result, 16)) |> String.downcase()
   end
 
-  def as_fn_call(nil, _calldata) do
+  def as_fn_call(nil, _calldata, _structs) do
     nil
   end
 
-  def as_fn_call(input, calldata) do
-    %{:name => input["name"], :args => as_fn_inputs(input["inputs"], calldata)}
+  def as_fn_call(function, calldata, structs) do
+    {inputs, _} = as_fn_inputs(function["inputs"], calldata, structs)
+    %{:name => function["name"], :args => inputs}
   end
 
-  def as_fn_inputs(inputs, calldata) do
-    {result, _} =
+  def as_fn_inputs(inputs, calldata, structs) do
+    {result, rest} =
       List.foldl(
         inputs,
         {[], calldata},
-        fn input, {acc_current, acc_calldata} ->
-          {fn_input, calldata_rest} = as_fn_input(input, acc_calldata)
-          {[fn_input | acc_current], calldata_rest}
+        fn input, {so_far, acc_calldata} ->
+          {fn_input, calldata_rest} = as_fn_input(input, so_far, acc_calldata, structs)
+          {[fn_input | so_far], calldata_rest}
         end
       )
 
-    Enum.reverse(result)
+    {Enum.reverse(result), rest}
   end
 
-  def as_fn_input(input, calldata) do
-    {value, calldata_rest} = get_value_for_type(input["type"], calldata)
+  def as_fn_input(input, so_far, calldata, structs) do
+    {value, calldata_rest} = get_value_for_type(input, so_far, calldata, structs)
     {%{:name => input["name"], :type => input["type"], :value => value}, calldata_rest}
   end
 
-  def get_value_for_type("Uint256", [value1, value2 | rest]) do
+  def get_value_for_type(
+        %{"type" => "core::array::Array::<" <> inner_type},
+        _so_far,
+        [
+          array_length | rest
+        ],
+        structs
+      ) do
+    inner_type = String.replace_suffix(inner_type, ">", "")
+    get_multiple_values_for_type(felt_to_int(array_length), inner_type, rest, structs)
+  end
+
+  def get_value_for_type(%{"type" => type, "name" => name}, so_far, calldata, structs) do
+    case String.ends_with?(type, "*") do
+      true ->
+        type = String.replace_suffix(type, "*", "!")
+        get_multiple_values_for_type(get_array_len(name, so_far), type, calldata, structs)
+
+      _ ->
+        get_value_for_single_type(type, calldata, structs)
+    end
+  end
+
+  def get_value_for_single_type("Uint256", [value1, value2 | rest], _structs) do
     {[value2, value1], rest}
   end
 
-  def get_value_for_type("core::integer::u256", [value1, value2 | rest]) do
+  def get_value_for_single_type("core::integer::u256", [value1, value2 | rest], _structs) do
     {[value2, value1], rest}
   end
 
-  def get_value_for_type(_, [value | rest]) do
-    {value, rest}
+  def get_value_for_single_type(type, [value | rest], structs) do
+    case Map.get(structs, type) do
+      nil ->
+        {value, rest}
+
+      %{"members" => members} ->
+        get_value_for_complex_type(members, [value | rest], structs)
+    end
+  end
+
+  def get_multiple_values_for_type(0, _type, list, _structs) do
+    {[], list}
+  end
+
+  def get_multiple_values_for_type(n, type, list, structs) do
+    {value, rest} = get_value_for_single_type(type, list, structs)
+    {values, final_rest} = get_multiple_values_for_type(n - 1, type, rest, structs)
+    {[value | values], final_rest}
+  end
+
+  def get_value_for_complex_type(members, list, structs) do
+    as_fn_inputs(members, list, structs)
+  end
+
+  def get_array_len(name, input_data) do
+    Enum.find(
+      input_data,
+      fn %{:name => input_name} ->
+        name <> "_len" == input_name
+      end
+    )
+    |> Map.get(:value)
+    |> felt_to_int
   end
 
   def felt_to_int(<<"0x", hexa_value::binary>>) do
@@ -135,10 +192,10 @@ defmodule StarknetExplorer.Calldata do
     value
   end
 
-  def get_input_data(block_id, address, selector, network) do
+  def get_functions_data(block_id, address, network) do
     case Rpc.get_class_at(block_id, address, network) do
       {:ok, class} ->
-        selectors = parse_class(class)
+        selectors = get_selectors(class)
 
         implementation_selector =
           Enum.find(
@@ -148,23 +205,31 @@ defmodule StarknetExplorer.Calldata do
             end
           )
 
-        case implementation_selector do
-          nil ->
-            find_by_selector(class, selector)
+        implementation_data =
+          case implementation_selector do
+            nil ->
+              nil
 
-          _ ->
-            {:ok, [implementation_address_or_hash]} =
-              Rpc.call(block_id, address, implementation_selector, network)
+            _ ->
+              {:ok, [implementation_address_or_hash]} =
+                Rpc.call(block_id, address, implementation_selector, network)
 
-            case Rpc.get_class(block_id, implementation_address_or_hash, network) do
-              {:ok, class} ->
-                find_by_selector(class, selector)
+              case Rpc.get_class(block_id, implementation_address_or_hash, network) do
+                {:ok, class} ->
+                  process_class_data(class, implementation_address_or_hash, :hash)
 
-              {:error, _error} ->
-                {:ok, class} = Rpc.get_class_at(block_id, implementation_address_or_hash, network)
-                find_by_selector(class, selector)
-            end
-        end
+                {:error, _error} ->
+                  {:ok, class} =
+                    Rpc.get_class_at(block_id, implementation_address_or_hash, network)
+
+                  process_class_data(class, implementation_address_or_hash, :address)
+              end
+          end
+
+        %{
+          :main => process_class_data(class, address, :address),
+          :implementation => implementation_data
+        }
 
       {:error, error} ->
         error |> IO.inspect()
@@ -172,7 +237,33 @@ defmodule StarknetExplorer.Calldata do
     end
   end
 
-  def parse_class(class) do
+  def process_class_data(class, id, id_type) do
+    class = normalize_abi(class)
+    {functions, structs} = functions_by_selector(class)
+
+    %{
+      :id => id,
+      :id_type => id_type,
+      :class => class,
+      :functions_by_selector => functions,
+      :structs_by_name => structs
+    }
+  end
+
+  def get_input_data(functions_data, selector) do
+    {functions, structs} =
+      case functions_data.implementation do
+        nil ->
+          {functions_data.main.functions_by_selector, functions_data.main.structs_by_name}
+
+        implementation ->
+          {implementation.functions_by_selector, implementation.structs_by_name}
+      end
+
+    {functions[selector], structs}
+  end
+
+  def get_selectors(class) do
     List.foldl(
       class["entry_points_by_type"]["EXTERNAL"],
       MapSet.new(),
@@ -182,18 +273,35 @@ defmodule StarknetExplorer.Calldata do
     )
   end
 
-  def get_input_data_for_hash(block_id, class_hash, selector, network) do
-    case Rpc.get_class(block_id, class_hash, network) do
-      {:ok, class} ->
-        find_by_selector(class, selector)
+  def functions_by_selector(class) do
+    functions_by_selector_and_version(class.abi, class["contract_class_version"])
+  end
 
-      {:error, error} ->
-        error |> IO.inspect()
-        nil
-    end
+  def functions_by_selector_and_version(abi, nil) do
+    {abi
+     |> List.foldl(%{}, &Map.put(&2, &1["name"] |> keccak(), &1)), %{}}
+  end
+
+  # we assume contract_class_version 0.1.0
+  def functions_by_selector_and_version(abi, _contract_class_version) do
+    abi
+    |> List.foldl(
+      {%{}, %{}},
+      fn
+        elem = %{"type" => "interface"}, {fn_acc, struct_acc} ->
+          {List.foldl(elem["items"], fn_acc, &Map.put(&2, &1["name"] |> keccak(), &1)),
+           struct_acc}
+
+        elem = %{"type" => "struct"}, {fn_acc, struct_acc} ->
+          {fn_acc, Map.put(struct_acc, elem["name"], elem)}
+
+        _elem, {fn_acc, struct_acc} ->
+          {fn_acc, struct_acc}
+      end
+    )
   end
 
-  def find_by_selector(class, selector) do
+  def normalize_abi(class) do
     abi =
       case class["abi"] do
         abi when is_binary(abi) ->
@@ -203,24 +311,8 @@ defmodule StarknetExplorer.Calldata do
           abi
       end
 
-    find_by_selector_and_version(abi, class["contract_class_version"], selector)
-  end
-
-  def find_by_selector_and_version(abi, nil, selector) do
-    Enum.find(
-      abi,
-      fn elem ->
-        elem["name"] |> keccak() == selector
-      end
-    )
-  end
-
-  # we assume contract_class_version 0.1.0
-  def find_by_selector_and_version(abi, _contract_class_version, selector) do
-    abi
-    |> Enum.map(& &1["items"])
-    |> Enum.filter(& &1)
-    |> Enum.concat()
-    |> Enum.find(&(&1["name"] |> keccak() == selector))
+    class
+    |> Map.delete("abi")
+    |> Map.put(:abi, abi)
   end
 end
diff --git a/lib/starknet_explorer_web/live/transaction_live.ex b/lib/starknet_explorer_web/live/transaction_live.ex
index d1126b3d..a409c2cd 100644
--- a/lib/starknet_explorer_web/live/transaction_live.ex
+++ b/lib/starknet_explorer_web/live/transaction_live.ex
@@ -535,7 +535,7 @@ defmodule StarknetExplorerWeb.TransactionLive do
                     <div>
                       <div class="list-h">Value</div>
                       <div class="break-all">
-                        <%= Utils.format_arg_value(arg) %>
+                        <pre><%= Utils.format_arg_value(arg) %></pre>
                       </div>
                     </div>
                   </div>
diff --git a/lib/starknet_explorer_web/live/utils.ex b/lib/starknet_explorer_web/live/utils.ex
index 3df1b5e1..9a1f85a1 100644
--- a/lib/starknet_explorer_web/live/utils.ex
+++ b/lib/starknet_explorer_web/live/utils.ex
@@ -68,6 +68,17 @@ defmodule StarknetExplorerWeb.Utils do
     shorten_block_hash(value)
   end
 
+  def format_arg_value(%{:type => "core::felt252", :value => value}) do
+    shorten_block_hash(value)
+  end
+
+  def format_arg_value(%{
+        :type => "core::starknet::contract_address::ContractAddress",
+        :value => value
+      }) do
+    shorten_block_hash(value)
+  end
+
   def format_arg_value(%{
         :type => "Uint256",
         :value => [<<"0x", high::binary>>, <<"0x", low::binary>>]
@@ -88,7 +99,27 @@ defmodule StarknetExplorerWeb.Utils do
        |> String.downcase())
   end
 
-  def format_arg_value(%{:value => value}) do
-    shorten_block_hash(value)
+  def format_arg_value(%{
+        :type => "core::array::Array::<" <> _rest,
+        :value => value
+      }) do
+    value
+    |> Jason.encode!()
+    |> Jason.Formatter.pretty_print()
+  end
+
+  def format_arg_value(%{:type => type, :value => value}) do
+    case String.ends_with?(type, "*") do
+      true ->
+        type = String.replace_suffix(type, "*", "")
+
+        value
+        |> Enum.map(&format_arg_value(%{:type => type, :value => &1}))
+        |> Jason.encode!()
+        |> Jason.Formatter.pretty_print()
+
+      _ ->
+        value
+    end
   end
 end