defmodule TradeMachine.GMGradeV2.MandateProfile do
  @moduledoc """
  The six canonical, versioned GM Mandate Profiles from AVC's model
  (`avc-grading-system/markdown/01-gm-mandate-logic.md` and
  `07-pillar-6-timeline-alignment.md`).

  A Mandate Profile is the *only* thing a mandate controls: the six Final GM
  Grade pillar weights and Timeline Alignment's mandate-specific internal
  targets. It does **not** reach into any other pillar's formula — those stay
  objective and mandate-independent. Per AVC's guardrails, Timeline Alignment is
  fixed at 20% for every mandate; no pillar weight exceeds 40% or falls below 5%.

  Profiles are keyed by `{mandate_key, version}`. Challenge authoring selects a
  mandate and pins its profile version; the version is frozen onto the grade so
  results stay reproducible when the profile is later retuned.

  The original prototype used inferred archetypes with a different vocabulary.
  Those values must not be mapped here by string similarity (see DECISIONS
  D-02).
  """

  @enforce_keys [
    :key,
    :version,
    :label,
    :strategic_question,
    :pillar_weights,
    :ideal_core_age,
    :age_penalty_below,
    :age_penalty_above,
    :prime_offset_range,
    :continuity_horizon,
    :young_minute_share_range,
    :veteran_count_range,
    :young_role_range
  ]
  defstruct @enforce_keys

  @type range :: %{min: number(), max: number()}

  @type t :: %__MODULE__{
          key: atom(),
          version: String.t(),
          label: String.t(),
          strategic_question: String.t(),
          pillar_weights: %{
            competitive_strength: float(),
            roster_construction: float(),
            contract_health: float(),
            cap_flexibility: float(),
            asset_management: float(),
            timeline_alignment: float()
          },
          # Ideal core age range (whole years on the season's first day).
          ideal_core_age: range(),
          # Asymmetric age-fit penalty rates (points per year outside the range).
          age_penalty_below: number(),
          age_penalty_above: number(),
          # Ideal Prime Timing Offset range (27.5 − age).
          prime_offset_range: range(),
          # Core Continuity horizon in seasons (includes the current season).
          continuity_horizon: pos_integer(),
          # Ideal young-player minute share of 240, as fractions (0.05 == 5%).
          young_minute_share_range: range(),
          # Ideal Established Veteran count.
          veteran_count_range: range(),
          # Ideal count of meaningful young rotation roles (≥ 8 assigned minutes).
          young_role_range: range()
        }

  @version "1.0.0"

  @keys ~w(championship_push run_it_back ascending retool selling rebuilding)a

  @profiles %{
    {:championship_push, @version} => %{
      key: :championship_push,
      version: @version,
      label: "Championship Push",
      strategic_question:
        "Did the GM create the strongest realistic championship roster possible?",
      pillar_weights: %{
        competitive_strength: 0.35,
        roster_construction: 0.20,
        contract_health: 0.10,
        cap_flexibility: 0.10,
        asset_management: 0.05,
        timeline_alignment: 0.20
      },
      ideal_core_age: %{min: 25, max: 31},
      age_penalty_below: 8,
      age_penalty_above: 7,
      prime_offset_range: %{min: -2.0, max: 1.0},
      continuity_horizon: 2,
      young_minute_share_range: %{min: 0.05, max: 0.20},
      veteran_count_range: %{min: 4, max: 8},
      young_role_range: %{min: 1, max: 3}
    },
    {:run_it_back, @version} => %{
      key: :run_it_back,
      version: @version,
      label: "Run It Back",
      strategic_question:
        "Did the GM preserve what already works while making the roster more sustainable and complete?",
      pillar_weights: %{
        competitive_strength: 0.25,
        roster_construction: 0.20,
        contract_health: 0.15,
        cap_flexibility: 0.15,
        asset_management: 0.05,
        timeline_alignment: 0.20
      },
      ideal_core_age: %{min: 24, max: 31},
      age_penalty_below: 9,
      age_penalty_above: 10,
      prime_offset_range: %{min: -1.5, max: 2.0},
      continuity_horizon: 3,
      young_minute_share_range: %{min: 0.10, max: 0.25},
      veteran_count_range: %{min: 3, max: 7},
      young_role_range: %{min: 1, max: 4}
    },
    {:ascending, @version} => %{
      key: :ascending,
      version: @version,
      label: "Ascending",
      strategic_question:
        "Did the GM make the young team meaningfully better without compromising its long-term trajectory?",
      pillar_weights: %{
        competitive_strength: 0.20,
        roster_construction: 0.15,
        contract_health: 0.15,
        cap_flexibility: 0.15,
        asset_management: 0.15,
        timeline_alignment: 0.20
      },
      ideal_core_age: %{min: 21, max: 27},
      age_penalty_below: 7,
      age_penalty_above: 12,
      prime_offset_range: %{min: 1.0, max: 5.0},
      continuity_horizon: 4,
      young_minute_share_range: %{min: 0.25, max: 0.45},
      veteran_count_range: %{min: 2, max: 5},
      young_role_range: %{min: 3, max: 6}
    },
    {:retool, @version} => %{
      key: :retool,
      version: @version,
      label: "Retool",
      strategic_question:
        "Did the GM fix the roster's structural problems without unnecessarily destroying its competitive foundation?",
      pillar_weights: %{
        competitive_strength: 0.15,
        roster_construction: 0.15,
        contract_health: 0.20,
        cap_flexibility: 0.20,
        asset_management: 0.10,
        timeline_alignment: 0.20
      },
      ideal_core_age: %{min: 23, max: 29},
      age_penalty_below: 8,
      age_penalty_above: 12,
      prime_offset_range: %{min: 0.0, max: 3.5},
      continuity_horizon: 3,
      young_minute_share_range: %{min: 0.20, max: 0.40},
      veteran_count_range: %{min: 2, max: 5},
      young_role_range: %{min: 2, max: 5}
    },
    {:selling, @version} => %{
      key: :selling,
      version: @version,
      label: "Selling",
      strategic_question:
        "Did the GM successfully convert current roster value into strong future assets?",
      pillar_weights: %{
        competitive_strength: 0.05,
        roster_construction: 0.05,
        contract_health: 0.10,
        cap_flexibility: 0.20,
        asset_management: 0.40,
        timeline_alignment: 0.20
      },
      ideal_core_age: %{min: 19, max: 25},
      age_penalty_below: 5,
      age_penalty_above: 15,
      prime_offset_range: %{min: 2.0, max: 6.0},
      continuity_horizon: 4,
      young_minute_share_range: %{min: 0.35, max: 0.60},
      veteran_count_range: %{min: 1, max: 4},
      young_role_range: %{min: 4, max: 8}
    },
    {:rebuilding, @version} => %{
      key: :rebuilding,
      version: @version,
      label: "Rebuilding",
      strategic_question:
        "Did the GM create a credible foundation for the franchise's next competitive era?",
      pillar_weights: %{
        competitive_strength: 0.05,
        roster_construction: 0.15,
        contract_health: 0.15,
        cap_flexibility: 0.15,
        asset_management: 0.30,
        timeline_alignment: 0.20
      },
      ideal_core_age: %{min: 19, max: 25},
      age_penalty_below: 4,
      age_penalty_above: 14,
      prime_offset_range: %{min: 2.5, max: 7.0},
      continuity_horizon: 5,
      young_minute_share_range: %{min: 0.40, max: 0.65},
      veteran_count_range: %{min: 2, max: 4},
      young_role_range: %{min: 4, max: 8}
    }
  }

  # Compile-time guardrail assertions: every profile's six weights sum to 1.0,
  # Timeline Alignment is fixed at 20%, and no weight breaches the 5%/40% guard.
  for {{key, version}, profile} <- @profiles do
    sum = profile.pillar_weights |> Map.values() |> Enum.sum()

    if abs(sum - 1.0) > 1.0e-9 do
      raise "MandateProfile #{key}/#{version} pillar weights sum to #{sum}, not 1.0"
    end

    if profile.pillar_weights.timeline_alignment != 0.20 do
      raise "MandateProfile #{key}/#{version} Timeline Alignment weight must be 0.20"
    end

    for {pillar, w} <- profile.pillar_weights do
      if w < 0.05 - 1.0e-9 or w > 0.40 + 1.0e-9 do
        raise "MandateProfile #{key}/#{version} #{pillar} weight #{w} breaches the 5%–40% guardrail"
      end
    end
  end

  @doc "The current default profile version."
  @spec current_version() :: String.t()
  def current_version, do: @version

  @doc "All canonical mandate keys."
  @spec keys() :: [atom()]
  def keys, do: @keys

  @doc "All profile versions present in the registry."
  @spec versions() :: [String.t()]
  def versions, do: @profiles |> Map.keys() |> Enum.map(&elem(&1, 1)) |> Enum.uniq()

  @doc "Fetches a profile, raising if the `{key, version}` pair is unknown."
  @spec get!(atom(), String.t()) :: t()
  def get!(key, version \\ @version) do
    case Map.fetch(@profiles, {key, version}) do
      {:ok, data} -> struct!(__MODULE__, data)
      :error -> raise ArgumentError, "unknown mandate profile #{inspect(key)}/#{inspect(version)}"
    end
  end

  @doc "Fetches a profile, returning `nil` for an unknown `{key, version}` pair."
  @spec get(atom(), String.t()) :: t() | nil
  def get(key, version \\ @version) do
    case Map.get(@profiles, {key, version}) do
      nil -> nil
      data -> struct!(__MODULE__, data)
    end
  end

  @doc """
  Rehydrates the profile copy stored in a challenge snapshot.

  Fields omitted by older snapshots retain the named registry version's value;
  fields present in the frozen document win. This keeps the snapshot copy, not
  the mutable registry, authoritative at grading time.
  """
  @spec from_frozen(map()) :: {:ok, t()} | {:error, :invalid_profile}
  def from_frozen(stored) when is_map(stored) do
    with {:ok, key_value} <- fetch(stored, :key),
         {:ok, key} <- mandate_key(key_value),
         {:ok, version} <- fetch(stored, :version),
         %__MODULE__{} = base <- get(key, version) do
      values =
        base
        |> Map.from_struct()
        |> Enum.map(fn {field, default} ->
          value =
            stored
            |> Map.get(field, Map.get(stored, Atom.to_string(field)))
            |> case do
              nil -> default
              frozen -> frozen
            end

          {field, normalize_frozen_value(field, value)}
        end)
        |> Map.new()

      {:ok, struct!(__MODULE__, values)}
    else
      _ -> {:error, :invalid_profile}
    end
  rescue
    _error in [ArgumentError, KeyError] -> {:error, :invalid_profile}
  end

  def from_frozen(_stored), do: {:error, :invalid_profile}

  @doc "All profiles at a given version, in canonical mandate order."
  @spec all(String.t()) :: [t()]
  def all(version \\ @version), do: Enum.map(@keys, &get!(&1, version))

  @doc "Human label for a mandate key."
  @spec label(atom()) :: String.t()
  def label(key), do: get!(key).label

  defp fetch(map, key) do
    case Map.fetch(map, key) do
      {:ok, value} -> {:ok, value}
      :error -> Map.fetch(map, Atom.to_string(key))
    end
  end

  defp mandate_key(key) when is_atom(key) do
    if key in @keys, do: {:ok, key}, else: :error
  end

  defp mandate_key(key) when is_binary(key) do
    case Enum.find(@keys, &(Atom.to_string(&1) == key)) do
      nil -> :error
      mandate -> {:ok, mandate}
    end
  end

  defp mandate_key(_key), do: :error

  defp normalize_frozen_value(field, value)
       when field in [
              :ideal_core_age,
              :prime_offset_range,
              :young_minute_share_range,
              :veteran_count_range,
              :young_role_range
            ] and is_map(value) do
    %{
      min: Map.get(value, :min, Map.get(value, "min")),
      max: Map.get(value, :max, Map.get(value, "max"))
    }
  end

  defp normalize_frozen_value(:key, value), do: normalize_key(value)

  defp normalize_frozen_value(:pillar_weights, value) when is_map(value) do
    Map.new(value, fn {key, weight} -> {normalize_key(key), weight} end)
  end

  defp normalize_frozen_value(_field, value), do: value

  defp normalize_key(key) when is_atom(key), do: key
  defp normalize_key(key) when is_binary(key), do: String.to_existing_atom(key)
end