defmodule Microwaveprop.Propagation.BandConfig do
  @moduledoc """
  Data-driven band configuration for the propagation scoring algorithm.

  This is the single source of truth for all scoring parameters: weights,
  thresholds, seasonal tables, and band-specific coefficients. When the
  algorithm is tuned or new bands are added, only this module changes.
  """

  @weights %{
    humidity: 0.18,
    time_of_day: 0.10,
    td_depression: 0.10,
    refractivity: 0.08,
    sky: 0.08,
    season: 0.08,
    wind: 0.05,
    rain: 0.08,
    pressure: 0.15,
    pwat: 0.10
  }

  @sunrise_table [7.4, 7.3, 7.0, 6.7, 6.35, 6.25, 6.35, 6.65, 6.9, 7.1, 7.35, 7.45]

  @tiers [
    %{min_score: 80, label: "EXCELLENT", color: "#00ffa3"},
    %{min_score: 65, label: "GOOD", color: "#7dffd4"},
    %{min_score: 50, label: "MARGINAL", color: "#ffe566"},
    %{min_score: 33, label: "POOR", color: "#ff9044"},
    %{min_score: 0, label: "NEGLIGIBLE", color: "#ff4f4f"}
  ]

  @humidity_beneficial_thresholds [{4, 55}, {7, 70}, {10, 82}, {14, 90}, {18, 95}, {22, 88}]
  @humidity_beneficial_default 75

  # Thresholds calibrated for HRRR-derived gradients (coarser than sounding data).
  # HRRR percentiles: p1=-230, p5=-162, p10=-130, p25=-94, p50=-70, p75=-53, p95=-40
  @refractivity_thresholds [
    {-200, 98, 85},
    {-150, 92, 80},
    {-100, 82, 72},
    {-75, 68, 62},
    {-55, 55, 55},
    {-40, 48, 48}
  ]
  @refractivity_default {42, 42}

  @band_configs %{
    10_000 => %{
      freq_mhz: 10_000,
      label: "10 GHz",
      o2_db_km: 0.007,
      h2o_coeff: 0.0,
      humidity_effect: :beneficial,
      humidity_penalty: 0.0,
      rain_k: 0.010,
      rain_alpha: 1.28,
      seasonal_base: %{
        1 => 38,
        2 => 40,
        3 => 22,
        4 => 55,
        5 => 68,
        6 => 90,
        7 => 95,
        8 => 75,
        9 => 78,
        10 => 88,
        11 => 78,
        12 => 25
      },
      seasonal_adj: %{},
      typical_range_km: 200,
      extended_range_km: 500,
      exceptional_range_km: 1000
    },
    24_000 => %{
      freq_mhz: 24_000,
      label: "24 GHz",
      o2_db_km: 0.02,
      h2o_coeff: 0.002,
      humidity_effect: :harmful,
      humidity_penalty: 1.6,
      rain_k: 0.070,
      rain_alpha: 1.07,
      seasonal_base: %{
        1 => 88,
        2 => 84,
        3 => 68,
        4 => 62,
        5 => 51,
        6 => 34,
        7 => 18,
        8 => 18,
        9 => 48,
        10 => 68,
        11 => 96,
        12 => 88
      },
      seasonal_adj: %{5 => -4, 6 => -8, 7 => -10, 8 => -10, 9 => -4},
      typical_range_km: 100,
      extended_range_km: 250,
      exceptional_range_km: 500
    },
    47_000 => %{
      freq_mhz: 47_000,
      label: "47 GHz",
      o2_db_km: 0.04,
      h2o_coeff: 0.003,
      humidity_effect: :harmful,
      humidity_penalty: 1.0,
      rain_k: 0.187,
      rain_alpha: 0.93,
      seasonal_base: %{
        1 => 90,
        2 => 88,
        3 => 78,
        4 => 68,
        5 => 55,
        6 => 38,
        7 => 22,
        8 => 22,
        9 => 48,
        10 => 74,
        11 => 96,
        12 => 90
      },
      seasonal_adj: %{},
      typical_range_km: 70,
      extended_range_km: 150,
      exceptional_range_km: 300
    },
    68_000 => %{
      freq_mhz: 68_000,
      label: "68 GHz",
      o2_db_km: 0.90,
      h2o_coeff: 0.007,
      humidity_effect: :harmful,
      humidity_penalty: 1.4,
      rain_k: 0.310,
      rain_alpha: 0.86,
      seasonal_base: %{
        1 => 90,
        2 => 88,
        3 => 78,
        4 => 65,
        5 => 50,
        6 => 32,
        7 => 18,
        8 => 18,
        9 => 44,
        10 => 70,
        11 => 92,
        12 => 90
      },
      seasonal_adj: %{},
      typical_range_km: 40,
      extended_range_km: 80,
      exceptional_range_km: 150
    },
    75_000 => %{
      freq_mhz: 75_000,
      label: "75 GHz",
      o2_db_km: 0.012,
      h2o_coeff: 0.006,
      humidity_effect: :harmful,
      humidity_penalty: 1.2,
      rain_k: 0.345,
      rain_alpha: 0.84,
      seasonal_base: %{
        1 => 90,
        2 => 90,
        3 => 80,
        4 => 68,
        5 => 55,
        6 => 38,
        7 => 22,
        8 => 22,
        9 => 48,
        10 => 74,
        11 => 96,
        12 => 90
      },
      seasonal_adj: %{},
      typical_range_km: 50,
      extended_range_km: 120,
      exceptional_range_km: 250
    },
    122_000 => %{
      freq_mhz: 122_000,
      label: "122 GHz",
      o2_db_km: 0.80,
      h2o_coeff: 0.010,
      humidity_effect: :harmful,
      humidity_penalty: 1.0,
      rain_k: 0.498,
      rain_alpha: 0.77,
      seasonal_base: %{
        1 => 92,
        2 => 90,
        3 => 78,
        4 => 62,
        5 => 45,
        6 => 28,
        7 => 15,
        8 => 15,
        9 => 38,
        10 => 68,
        11 => 92,
        12 => 92
      },
      seasonal_adj: %{},
      typical_range_km: 30,
      extended_range_km: 80,
      exceptional_range_km: 140
    },
    134_000 => %{
      freq_mhz: 134_000,
      label: "134 GHz",
      o2_db_km: 0.08,
      h2o_coeff: 0.015,
      humidity_effect: :harmful,
      humidity_penalty: 1.3,
      rain_k: 0.520,
      rain_alpha: 0.75,
      seasonal_base: %{
        1 => 92,
        2 => 90,
        3 => 78,
        4 => 65,
        5 => 48,
        6 => 30,
        7 => 18,
        8 => 18,
        9 => 42,
        10 => 70,
        11 => 92,
        12 => 92
      },
      seasonal_adj: %{},
      typical_range_km: 40,
      extended_range_km: 100,
      exceptional_range_km: 160
    },
    241_000 => %{
      freq_mhz: 241_000,
      label: "241 GHz",
      o2_db_km: 0.08,
      h2o_coeff: 0.30,
      humidity_effect: :harmful,
      humidity_penalty: 3.0,
      rain_k: 0.550,
      rain_alpha: 0.70,
      seasonal_base: %{
        1 => 95,
        2 => 92,
        3 => 75,
        4 => 55,
        5 => 35,
        6 => 15,
        7 => 8,
        8 => 8,
        9 => 30,
        10 => 65,
        11 => 95,
        12 => 95
      },
      seasonal_adj: %{},
      typical_range_km: 10,
      extended_range_km: 50,
      exceptional_range_km: 115
    }
  }

  @doc "Returns the band config for the given frequency in MHz, or nil if not found."
  @spec get(integer()) :: map() | nil
  def get(freq_mhz), do: Map.get(@band_configs, freq_mhz)

  @doc "Returns all band configs sorted by frequency (ascending)."
  @spec all_bands() :: [map()]
  def all_bands do
    @band_configs
    |> Enum.sort_by(fn {freq, _config} -> freq end)
    |> Enum.map(fn {_freq, config} -> config end)
  end

  @doc "Returns all supported frequencies sorted ascending."
  @spec all_freqs() :: [integer()]
  def all_freqs do
    @band_configs
    |> Map.keys()
    |> Enum.sort()
  end

  @doc "Returns the scoring weights map. All 10 values sum to 1.0."
  @spec weights() :: map()
  def weights, do: @weights

  @doc "Returns the 12-element sunrise hour table (Jan-Dec, local time)."
  @spec sunrise_table() :: [float()]
  def sunrise_table, do: @sunrise_table

  @doc "Returns score tier definitions ordered by threshold descending."
  @spec tiers() :: [map()]
  def tiers, do: @tiers

  @doc "Returns humidity beneficial thresholds as {hour, score} tuples."
  @spec humidity_beneficial_thresholds() :: [{integer(), integer()}]
  def humidity_beneficial_thresholds, do: @humidity_beneficial_thresholds

  @doc "Returns the default humidity beneficial score."
  @spec humidity_beneficial_default() :: integer()
  def humidity_beneficial_default, do: @humidity_beneficial_default

  @doc "Returns refractivity thresholds as {gradient, score_beneficial, score_harmful} tuples."
  @spec refractivity_thresholds() :: [{number(), number(), number()}]
  def refractivity_thresholds, do: @refractivity_thresholds

  @doc "Returns the default refractivity scores as {beneficial, harmful}."
  @spec refractivity_default() :: {number(), number()}
  def refractivity_default, do: @refractivity_default
end