Spectral-Finance · sojinmm · Apr 7, 2025
diff --git a/lux/lib/lux/lenses/discord/analytics/get_channel_activity.ex b/lux/lib/lux/lenses/discord/analytics/get_channel_activity.ex
@@ -0,0 +1,130 @@
+defmodule Lux.Lenses.Discord.Analytics.GetChannelActivity do
+  @moduledoc """
+  A lens for retrieving activity metrics for a Discord channel.
+  This lens provides detailed analytics about channel activity including:
+  - Message count over time
+  - Active users count
+  - Peak activity periods
+  - Message type distribution
+
+  ## Examples
+      iex> GetChannelActivity.focus(%{
+      ...>   channel_id: "123456789012345678",
+      ...>   time_range: "24h"  # 24h, 7d, 30d
+      ...> }, %{})
+      {:ok, %{
+        message_count: 150,
+        active_users: 25,
+        peak_hour: "18:00",
+        message_types: %{
+          text: 120,
+          image: 20,
+          link: 10
+        },
+        activity_timeline: [
+          %{hour: "00:00", count: 5},
+          %{hour: "01:00", count: 3},
+          # ... more hourly data
+        ]
+      }}
+  """
+
+  alias Lux.Integrations.Discord
+
+  use Lux.Lens,
+    name: "Get Discord Channel Activity",
+    description: "Retrieves detailed activity metrics for a Discord channel",
+    url: "https://discord.com/api/v10/channels/:channel_id/messages",
+    method: :get,
+    headers: Discord.headers(),
+    auth: Discord.auth(),
+    schema: %{
+      type: :object,
+      properties: %{
+        channel_id: %{
+          type: :string,
+          description: "The ID of the channel to analyze",
+          pattern: "^[0-9]{17,20}$"
+        },
+        time_range: %{
+          type: :string,
+          description: "Time range for analysis (24h, 7d, or 30d)",
+          enum: ["24h", "7d", "30d"],
+          default: "24h"
+        },
+        limit: %{
+          type: :integer,
+          description: "Maximum number of messages to analyze",
+          minimum: 1,
+          maximum: 100,
+          default: 100
+        }
+      },
+      required: ["channel_id"]
+    }
+
+  @doc """
+  Transforms the Discord API response into activity metrics.
+  Analyzes message data to generate activity statistics.
+  """
+  @impl true
+  def after_focus(messages) when is_list(messages) do
+    metrics = %{
+      message_count: length(messages),
+      active_users: count_active_users(messages),
+      peak_hour: find_peak_hour(messages),
+      message_types: analyze_message_types(messages),
+      activity_timeline: generate_timeline(messages)
+    }
+
+    {:ok, metrics}
+  end
+
+  def after_focus(%{"message" => message}) do
+    {:error, %{"message" => message}}
+  end
+
+  # Private helper functions
+
+  defp count_active_users(messages) do
+    messages
+    |> Enum.map(& &1["author"]["id"])
+    |> Enum.uniq()
+    |> length()
+  end
+
+  defp find_peak_hour([]) do
+    "00:00"
+  end
+
+  defp find_peak_hour(messages) do
+    messages
+    |> Enum.group_by(fn message ->
+      {:ok, timestamp, _} = DateTime.from_iso8601(message["timestamp"])
+      "#{String.pad_leading("#{timestamp.hour}", 2, "0")}:00"
+    end)
+    |> Enum.max_by(fn {_hour, msgs} -> length(msgs) end)
+    |> elem(0)
+  end
+
+  defp analyze_message_types(messages) do
+    messages
+    |> Enum.reduce(%{text: 0, image: 0, link: 0}, fn message, acc ->
+      cond do
+        message["attachments"] != [] -> Map.update!(acc, :image, &(&1 + 1))
+        String.contains?(message["content"] || "", "http") -> Map.update!(acc, :link, &(&1 + 1))
+        true -> Map.update!(acc, :text, &(&1 + 1))
+      end
+    end)
+  end
+
+  defp generate_timeline(messages) do
+    messages
+    |> Enum.group_by(fn message ->
+      {:ok, timestamp, _} = DateTime.from_iso8601(message["timestamp"])
+      "#{String.pad_leading("#{timestamp.hour}", 2, "0")}:00"
+    end)
+    |> Enum.map(fn {hour, msgs} -> %{hour: hour, count: length(msgs)} end)
+    |> Enum.sort_by(& &1.hour)
+  end
+end
diff --git a/lux/test/unit/lux/lenses/discord/analytics/get_channel_activity_test.exs b/lux/test/unit/lux/lenses/discord/analytics/get_channel_activity_test.exs
@@ -0,0 +1,146 @@
+defmodule Lux.Lenses.Discord.Analytics.GetChannelActivityTest do
+  @moduledoc """
+  Test suite for the GetChannelActivity module.
+  These tests verify the lens's ability to:
+  - Retrieve activity metrics for a Discord channel
+  - Process message data into meaningful statistics
+  - Handle Discord API errors appropriately
+  - Validate input parameters
+  """
+
+  use UnitAPICase, async: true
+  alias Lux.Lenses.Discord.Analytics.GetChannelActivity
+
+  @channel_id "123456789012345678"
+  @mock_messages [
+    %{
+      "id" => "111111111111111111",
+      "content" => "Hello world",
+      "author" => %{"id" => "222222222222222222", "username" => "User 1"},
+      "timestamp" => "2024-03-28T10:00:00Z",
+      "attachments" => []
+    },
+    %{
+      "id" => "333333333333333333",
+      "content" => "Check this link https://example.com",
+      "author" => %{"id" => "444444444444444444", "username" => "User 2"},
+      "timestamp" => "2024-03-28T10:30:00Z",
+      "attachments" => []
+    },
+    %{
+      "id" => "555555555555555555",
+      "content" => "Look at this image",
+      "author" => %{"id" => "222222222222222222", "username" => "User 1"},
+      "timestamp" => "2024-03-28T10:00:00Z",
+      "attachments" => [%{"url" => "https://example.com/image.jpg"}]
+    }
+  ]
+
+  setup do
+    Req.Test.verify_on_exit!()
+    :ok
+  end
+
+  describe "focus/2" do
+    test "successfully retrieves channel activity metrics" do
+      Req.Test.expect(Lux.Lens, fn conn ->
+        assert conn.method == "GET"
+        assert conn.request_path == "/api/v10/channels/:channel_id/messages"
+        assert Plug.Conn.get_req_header(conn, "authorization") == ["Bot test-discord-token"]
+
+        conn
+        |> Plug.Conn.put_resp_content_type("application/json")
+        |> Plug.Conn.send_resp(200, Jason.encode!(@mock_messages))
+      end)
+
+      assert {:ok, metrics} = GetChannelActivity.focus(%{
+        "channel_id" => @channel_id
+      }, %{})
+
+      # Verify basic metrics
+      assert metrics.message_count == 3
+      assert metrics.active_users == 2
+      assert metrics.peak_hour == "10:00"
+
+      # Verify message type distribution
+      assert metrics.message_types.text == 1
+      assert metrics.message_types.link == 1
+      assert metrics.message_types.image == 1
+
+      # Verify timeline
+      timeline = Enum.find(metrics.activity_timeline, &(&1.hour == "10:00"))
+      assert timeline.count == 3
+    end
+
+    test "handles empty channel" do
+      Req.Test.expect(Lux.Lens, fn conn ->
+        assert conn.method == "GET"
+        assert conn.request_path == "/api/v10/channels/:channel_id/messages"
+        assert Plug.Conn.get_req_header(conn, "authorization") == ["Bot test-discord-token"]
+
+        conn
+        |> Plug.Conn.put_resp_content_type("application/json")
+        |> Plug.Conn.send_resp(200, Jason.encode!([]))
+      end)
+
+      assert {:ok, metrics} = GetChannelActivity.focus(%{
+        "channel_id" => @channel_id
+      }, %{})
+
+      assert metrics.message_count == 0
+      assert metrics.active_users == 0
+      assert metrics.message_types == %{text: 0, image: 0, link: 0}
+      assert metrics.activity_timeline == []
+      assert metrics.peak_hour == "00:00"
+    end
+
+    test "handles Discord API error" do
+      Req.Test.expect(Lux.Lens, fn conn ->
+        assert conn.method == "GET"
+        assert conn.request_path == "/api/v10/channels/:channel_id/messages"
+        assert Plug.Conn.get_req_header(conn, "authorization") == ["Bot test-discord-token"]
+
+        conn
+        |> Plug.Conn.put_resp_content_type("application/json")
+        |> Plug.Conn.send_resp(403, Jason.encode!(%{
+          "message" => "Missing Permissions"
+        }))
+      end)
+
+      assert {:error, %{"message" => "Missing Permissions"}} = GetChannelActivity.focus(%{
+        "channel_id" => @channel_id
+      }, %{})
+    end
+  end
+    
+  describe "schema validation" do
+    test "validates required fields" do
+      lens = GetChannelActivity.view()
+      assert lens.schema.required == ["channel_id"]
+    end
+
+    test "validates channel ID format" do
+      lens = GetChannelActivity.view()
+      channel_id = lens.schema.properties.channel_id
+      assert channel_id.type == :string
+      assert channel_id.pattern == "^[0-9]{17,20}$"
+    end
+
+    test "validates time range enum" do
+      lens = GetChannelActivity.view()
+      time_range = lens.schema.properties.time_range
+      assert time_range.type == :string
+      assert time_range.enum == ["24h", "7d", "30d"]
+      assert time_range.default == "24h"
+    end
+
+    test "validates limit parameter" do
+      lens = GetChannelActivity.view()
+      limit = lens.schema.properties.limit
+      assert limit.type == :integer
+      assert limit.minimum == 1
+      assert limit.maximum == 100
+      assert limit.default == 100
+    end
+  end
+end