From 0ab2e5ba2b0631b28b5b1405559237b3913c878f Mon Sep 17 00:00:00 2001
From: Dawid Rycerz <dawid@rycerz.xyz>
Date: Sun, 23 Mar 2025 17:11:39 +0100
Subject: feat: initialize Phoenix application for weather alerts

This commit sets up the initial Silmataivas project structure, including: Phoenix web framework configuration, database models for users and locations, weather polling service, notification system, Docker and deployment configurations, CI/CD pipeline setup
---
 lib/silmataivas/weather_poller.ex | 102 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 102 insertions(+)
 create mode 100644 lib/silmataivas/weather_poller.ex

(limited to 'lib/silmataivas/weather_poller.ex')

diff --git a/lib/silmataivas/weather_poller.ex b/lib/silmataivas/weather_poller.ex
new file mode 100644
index 0000000..b42b184
--- /dev/null
+++ b/lib/silmataivas/weather_poller.ex
@@ -0,0 +1,102 @@
+defmodule Silmataivas.WeatherPoller do
+  require Logger
+  alias Silmataivas.{Users, Notifications.NtfyNotifier}
+
+  @api_url "https://api.openweathermap.org/data/2.5/forecast"
+  # Check forecasts within the next 24 hours
+  @alert_window_hours 24
+
+  def check_all do
+    Logger.info("🔄 Checking weather forecast for all users...")
+
+    Users.list_users_with_locations()
+    |> Enum.each(&check_user_weather/1)
+  end
+
+  def check_user_weather(%{user_id: user_id, location: %{latitude: lat, longitude: lon}} = _user) do
+    case fetch_forecast(lat, lon) do
+      {:ok, forecasts} ->
+        case find_first_alert_entry(forecasts) do
+          nil -> :ok
+          entry -> NtfyNotifier.send_alert(user_id, entry)
+        end
+
+      {:error, reason} ->
+        Logger.error("❌ Error fetching forecast for user #{user_id}: #{inspect(reason)}")
+    end
+  end
+
+  # Add this clause to handle users with missing location data
+  def check_user_weather(%{user_id: user_id} = user) do
+    Logger.warning(
+      "⚠️ User #{user_id} has missing or incomplete location data: #{inspect(user)}",
+      []
+    )
+
+    :ok
+  end
+
+  # Add a catch-all clause to handle unexpected data formats
+  def check_user_weather(invalid_user) do
+    Logger.error("❌ Invalid user data structure: #{inspect(invalid_user)}")
+    :ok
+  end
+
+  defp fetch_forecast(lat, lon) do
+    api_key = Application.fetch_env!(:silmataivas, :openweathermap_api_key)
+
+    Req.get(
+      url: @api_url,
+      params: [
+        lat: lat,
+        lon: lon,
+        units: "metric",
+        appid: api_key
+      ]
+    )
+    |> case do
+      {:ok, %{status: 200, body: %{"list" => forecast_list}}} ->
+        {:ok, forecast_list}
+
+      {:ok, %{status: code, body: body}} ->
+        {:error, {code, body}}
+
+      error ->
+        error
+    end
+  end
+
+  defp dangerous_conditions?(
+         %{
+           "main" => %{"temp" => temp},
+           "wind" => %{"speed" => speed},
+           "dt_txt" => time_str
+         } = entry
+       ) do
+    rain_mm = get_in(entry, ["rain", "3h"]) || 0.0
+    wind_kmh = speed * 3.6
+
+    cond do
+      wind_kmh > 80 -> log_reason("Wind", wind_kmh, time_str)
+      rain_mm > 40 -> log_reason("Rain", rain_mm, time_str)
+      temp < 0 -> log_reason("Temperature", temp, time_str)
+      true -> false
+    end
+  end
+
+  defp find_first_alert_entry(forecast_list) do
+    now = DateTime.utc_now()
+
+    forecast_list
+    |> Enum.take_while(fn %{"dt" => ts} ->
+      forecast_time = DateTime.from_unix!(ts)
+      DateTime.diff(forecast_time, now, :hour) <= @alert_window_hours
+    end)
+    |> Enum.find(&dangerous_conditions?/1)
+  end
+
+  defp log_reason(type, value, time_str) do
+    Logger.info("🚨 #{type} threshold exceeded: #{value} at #{time_str}")
+    true
+  end
+end
-- 
cgit v1.2.3