defmodule MicrowavepropWeb.WeatherMapLive do
  @moduledoc false
  use MicrowavepropWeb, :live_view

  alias Microwaveprop.Weather

  @initial_bounds %{
    "south" => 29.5,
    "north" => 36.3,
    "west" => -101.5,
    "east" => -92.5
  }

  @layers [
    # Surface
    %{
      id: "temperature",
      label: "Temperature",
      unit: "°C",
      group: "Surface",
      desc: "2m air temperature. Warm, humid air increases refractivity and ducting potential at lower frequencies."
    },
    %{
      id: "dewpoint_depression",
      label: "Td Depression",
      unit: "°C",
      group: "Surface",
      desc:
        "Temperature minus dewpoint. Small values (< 5°C) mean moist boundary layer — favorable for ducting at 10 GHz, but increases absorption above 24 GHz."
    },
    %{
      id: "surface_rh",
      label: "Humidity",
      unit: "%",
      group: "Surface",
      desc:
        "Relative humidity from surface T and Td. High RH supports refractivity gradients that bend microwave signals."
    },
    %{
      id: "pwat",
      label: "PWAT",
      unit: "mm",
      group: "Surface",
      desc:
        "Precipitable water — total moisture in the atmospheric column. High values signal rain fade risk for 24 GHz and above."
    },
    %{
      id: "surface_refractivity",
      label: "Refractivity",
      unit: "N",
      group: "Surface",
      desc:
        "Radio refractivity (N-units) at the surface. Typical values 280–380. Higher N means the atmosphere bends signals more toward the ground."
    },
    %{
      id: "refractivity_gradient",
      label: "N-Gradient",
      unit: "N/km",
      group: "Surface",
      desc:
        "Minimum refractivity gradient in the profile. Standard is −40 N/km. Below −157 N/km signals are trapped in a duct. More negative = stronger ducting."
    },
    %{
      id: "bl_height",
      label: "BL Height",
      unit: "m",
      group: "Surface",
      desc:
        "Planetary boundary layer height. Shallow BL (< 500m) concentrates moisture and heat near the surface, favoring temperature inversions and ducting."
    },
    # Upper Air
    %{
      id: "temp_850mb",
      label: "T @ 850mb",
      unit: "°C",
      group: "Upper Air",
      desc:
        "Temperature at 850 mb (~1500m altitude). Warm 850mb air over cool surface air indicates a capping inversion — a classic ducting setup."
    },
    %{
      id: "dewpoint_850mb",
      label: "Td @ 850mb",
      unit: "°C",
      group: "Upper Air",
      desc:
        "Dewpoint at 850 mb. A sharp moisture drop between the surface and 850mb creates an elevated refractivity gradient that can form ducts."
    },
    %{
      id: "lapse_rate",
      label: "Lapse Rate",
      unit: "°C/km",
      group: "Upper Air",
      desc:
        "Temperature decrease per km from surface to 700mb. Low rates (< 5 °C/km) mean stable air that preserves inversions. High rates (> 8) mean convective mixing that destroys them."
    },
    %{
      id: "inversion_strength",
      label: "Inversion",
      unit: "°C",
      group: "Upper Air",
      desc:
        "Strongest temperature increase between adjacent levels. Inversions trap microwave signals. > 3°C is significant, > 5°C is strong."
    },
    %{
      id: "inversion_base_m",
      label: "Inv. Base",
      unit: "m",
      group: "Upper Air",
      desc:
        "Height (m AGL) where the strongest inversion begins. Surface-based inversions (< 200m) create surface ducts. Elevated inversions create elevated ducts."
    },
    # Ducting
    %{
      id: "ducting",
      label: "Ducting",
      unit: "",
      group: "Ducting",
      desc:
        "Whether a trapping layer (modified refractivity decreasing with height) was detected in the profile. Green = duct present, signals can travel far beyond line of sight."
    },
    %{
      id: "duct_base_m",
      label: "Duct Base",
      unit: "m",
      group: "Ducting",
      desc:
        "Height of the lowest duct base. Surface ducts (< 100m) are most effective for ground-based stations. Elevated ducts require antennas near the duct height."
    },
    %{
      id: "duct_strength",
      label: "Duct Strength",
      unit: "M",
      group: "Ducting",
      desc:
        "Duct trapping strength in modified refractivity (M) units. > 10 M is moderate, > 20 M is strong. Stronger ducts trap a wider range of frequencies."
    }
  ]

  @impl true
  def mount(_params, _session, socket) do
    if connected?(socket) do
      Phoenix.PubSub.subscribe(Microwaveprop.PubSub, "weather:updated")
    end

    data = Weather.latest_weather_grid(@initial_bounds)
    valid_time = if data != [], do: hd(data).valid_time

    {:ok,
     assign(socket,
       page_title: "Weather Map",
       layers: @layers,
       selected_layer: "refractivity_gradient",
       initial_data_json: Jason.encode!(data),
       valid_time: valid_time,
       bounds: @initial_bounds
     )}
  end

  @impl true
  def handle_event("select_layer", %{"layer" => layer_id}, socket) do
    {:noreply, assign(socket, :selected_layer, layer_id)}
  end

  def handle_event("map_bounds", bounds, socket) do
    data = Weather.latest_weather_grid(bounds)

    socket =
      socket
      |> assign(:bounds, bounds)
      |> push_event("update_weather", %{data: data})

    {:noreply, socket}
  end

  def handle_event("point_detail", %{"lat" => lat, "lon" => lon}, socket) do
    detail =
      if socket.assigns.valid_time do
        Weather.weather_point_detail(lat, lon, socket.assigns.valid_time)
      end

    payload = detail || %{}
    {:noreply, push_event(socket, "point_detail", payload)}
  end

  @impl true
  def handle_info({:weather_updated, _valid_time}, socket) do
    data = Weather.latest_weather_grid(socket.assigns.bounds)
    valid_time = if data != [], do: hd(data).valid_time

    socket =
      socket
      |> assign(:valid_time, valid_time)
      |> push_event("update_weather", %{data: data})

    {:noreply, socket}
  end

  @group_order ["Surface", "Upper Air", "Ducting"]

  defp group_layers(layers) do
    layers
    |> Enum.group_by(& &1.group)
    |> Enum.sort_by(fn {group, _} -> Enum.find_index(@group_order, &(&1 == group)) || 99 end)
  end

  defp layer_description(layers, selected_id) do
    case Enum.find(layers, &(&1.id == selected_id)) do
      %{desc: desc} -> desc
      _ -> nil
    end
  end

  @impl true
  def render(assigns) do
    ~H"""
    <div class="relative w-screen h-screen overflow-hidden">
      <%!-- Full-page map --%>
      <div
        id="weather-map"
        phx-hook="WeatherMap"
        phx-update="ignore"
        data-weather={@initial_data_json}
        data-layers={Jason.encode!(@layers)}
        data-selected-layer={@selected_layer}
        class="absolute inset-0 z-0"
      >
      </div>

      <%!-- Top-left control panel --%>
      <div
        id="weather-controls"
        class="absolute top-2 left-12 z-[1000] flex flex-col gap-2 max-w-[calc(100vw-4rem)] md:left-14 md:top-3 md:max-w-none"
      >
        <div class="bg-base-100/90 shadow rounded-box border border-base-300 p-2 md:p-3 flex flex-col gap-2">
          <div class="font-bold text-sm leading-tight px-1 flex items-center justify-between gap-2">
            <div class="min-w-0">
              <span class="hidden md:inline">HRRR Weather Data</span>
              <span class="md:hidden">Weather</span>
              <div class="font-normal text-xs opacity-70">
                <%= if @valid_time do %>
                  {Calendar.strftime(@valid_time, "%Y-%m-%d %H:%M UTC")}
                <% else %>
                  No data available
                <% end %>
              </div>
            </div>
            <div
              id="weather-utc-clock"
              phx-hook="UtcClock"
              class="font-mono text-xs opacity-70 tabular-nums shrink-0"
            >
            </div>
          </div>

          <%!-- Layer pill buttons grouped --%>
          <div class="flex flex-col gap-1.5">
            <div :for={{group, layers} <- group_layers(@layers)}>
              <div class="text-[10px] font-semibold opacity-50 uppercase tracking-wider px-1 mb-0.5">
                {group}
              </div>
              <div class="flex flex-wrap gap-1">
                <button
                  :for={layer <- layers}
                  phx-click="select_layer"
                  phx-value-layer={layer.id}
                  class={[
                    "btn btn-xs rounded-full",
                    if(@selected_layer == layer.id, do: "btn-primary", else: "btn-ghost")
                  ]}
                >
                  {layer.label}
                </button>
              </div>
            </div>
          </div>

          <%!-- Layer description --%>
          <div class="text-xs opacity-70 px-1 leading-snug">
            {layer_description(@layers, @selected_layer)}
          </div>

          <%!-- Links --%>
          <div class="flex flex-col gap-1 border-t border-base-300 pt-2">
            <.link navigate="/map" class="btn btn-xs btn-ghost justify-start">
              Propagation Prediction Map
            </.link>
          </div>
        </div>
      </div>

      <%!-- Point detail panel --%>
      <div
        id="weather-detail-panel"
        phx-update="ignore"
        class={[
          "bg-neutral text-neutral-content shadow-lg border border-base-300 overflow-hidden overflow-y-auto z-[1001]",
          "fixed bottom-0 left-0 right-0 max-h-[50vh] rounded-t-2xl",
          "md:absolute md:top-3 md:bottom-auto md:left-auto md:right-auto md:max-h-[60vh] md:max-w-sm md:rounded-box"
        ]}
        style="display:none;"
      >
      </div>
    </div>

    <Layouts.flash_group flash={@flash} />
    """
  end
end