print issues as table

and mix format. also: please not that this is my approach to
Exercise: OrganizingAProject-4

issues/lib/issues/cli.ex

@@ -26,25 +26,26 @@ defmodule Issues.CLI do
     )
     |> elem(1)
     |> args_to_internal_representation
-
   end
 
   def args_to_internal_representation([user, project, count]) do
-    { user, project, String.to_integer(count) }
+    {user, project, String.to_integer(count)}
   end
 
   def args_to_internal_representation([user, project]) do
-    { user, project, @default_count }
+    {user, project, @default_count}
   end
 
-  def args_to_internal_representation(_) do # either bad arg or --help
+  # either bad arg or --help
+  def args_to_internal_representation(_) do
     :help
   end
 
   def process(:help) do
-    IO.puts """
+    IO.puts("""
     usage: issues <user> <project> [count | #{@default_count}]
-    """
+    """)
+
     System.halt(0)
   end
 
@@ -57,35 +58,62 @@ defmodule Issues.CLI do
   end
 
   def decode_response({:ok, body}), do: body
+
   def decode_response({:error, error}) do
-    IO.puts "Error fetching from Github: #{error["message"]}"
+    IO.puts("Error fetching from Github: #{error["message"]}")
     System.halt(2)
   end
 
   def sort_into_descending_order(list_of_issues) do
     list_of_issues
-    |> Enum.sort(fn lhs, rhs -> Map.get(lhs, "created_at") >= Map.get(rhs, "created_at") end) 
+    |> Enum.sort(fn lhs, rhs -> Map.get(lhs, "created_at") >= Map.get(rhs, "created_at") end)
   end
 
   def last(list, count) do
     list
     |> Enum.take(count)
-    |> Enum.reverse
+    |> Enum.reverse()
   end
 
   def show_issues_as_table(issues_list) do
-    # get the width of id-column = length(max(all_ids)) + 2
-    # do the same for created_at and title
+    # get the width of each colum for id, created at and title
+    longest_id =
+      issues_list
+      |> Enum.map(&Map.get(&1, "id"))
+      |> Enum.max_by(&(String.length("#{&1}") + 2))
 
-    IO.puts "#id | created_at | title"
+    id_column_width = String.length(Integer.to_string(longest_id))
 
+    longest_creation_date =
+      issues_list
+      |> Enum.map(&Map.get(&1, "created_at"))
+      |> Enum.max_by(&(String.length(&1) + 2))
+
+    creation_date_width = String.length(longest_creation_date)
+
+    longest_title =
+      issues_list
+      |> Enum.map(&Map.get(&1, "title"))
+      |> Enum.max_by(&(String.length(&1) + 2))
+
+    title_length = String.length(longest_title)
+
+    # print the title
+    IO.puts(
+      "#{String.pad_trailing("#id", id_column_width)} | #{String.pad_trailing("created_at", creation_date_width)} | #{String.pad_trailing("title", title_length)} "
+    )
+
+    # print seperator
+    IO.puts(
+      "#{String.pad_trailing("-", id_column_width, "-")}-+-#{String.pad_trailing("-", creation_date_width, "-")}-+-#{String.pad_trailing("-", title_length, "-")}-"
+    )
+
+    # print each issue
     issues_list
-    |> Enum.each(fn issue -> IO.puts "#{Map.get(issue, "id")} | #{Map.get(issue, "created_at")} | #{Map.get(issue, "title")}" end)
-
-    # list is a list of maps
-    # print #id | created_at | title
-    # print ----+------------+------
-    # print issue.id | issue.created_at | issue.title
-    # 
+    |> Enum.each(fn issue ->
+      IO.puts(
+        "#{String.pad_trailing(Integer.to_string(Map.get(issue, "id")), id_column_width)} | #{String.pad_trailing(Map.get(issue, "created_at"), creation_date_width)} | #{String.pad_trailing(Map.get(issue, "title"), title_length)}"
+      )
+    end)
   end
 end