defmodule Odinsea.Channel.Players do
  @moduledoc """
  Player storage for channel server.
  Manages online player state and lookups.
  
  Ported from Java handling.channel.PlayerStorage
  
  Uses ETS for fast in-memory lookups.
  """

  require Logger

  @table :channel_players

  @doc """
  Starts the player storage (creates ETS table).
  """
  def start_link do
    :ets.new(@table, [
      :set,
      :public,
      :named_table,
      read_concurrency: true,
      write_concurrency: true
    ])
    
    {:ok, self()}
  end

  @doc """
  Adds a player to the channel storage.
  """
  def add_player(character_id, player_data) do
    :ets.insert(@table, {character_id, player_data})
    :ok
  end

  @doc """
  Removes a player from the channel storage.
  """
  def remove_player(character_id) do
    :ets.delete(@table, character_id)
    :ok
  end

  @doc """
  Gets player data by character ID.
  Returns nil if not found.
  """
  def get_player(character_id) do
    case :ets.lookup(@table, character_id) do
      [{^character_id, data}] -> data
      [] -> nil
    end
  end

  @doc """
  Checks if a character is online in this channel.
  """
  def is_online?(character_id) do
    :ets.member(@table, character_id)
  end

  @doc """
  Gets all online players.
  """
  def get_all_players do
    :ets.tab2list(@table)
    |> Enum.map(fn {_id, data} -> data end)
  end

  @doc """
  Gets player count.
  """
  def count do
    :ets.info(@table, :size)
  end

  @doc """
  Gets a player by name.
  """
  def get_player_by_name(name) do
    @table
    |> :ets.tab2list()
    |> Enum.find(fn {_id, data} -> data.name == name end)
    |> case do
      nil -> nil
      {_, data} -> data
    end
  end

  @doc """
  Updates player data.
  """
  def update_player(character_id, updates) do
    case get_player(character_id) do
      nil -> :error
      data ->
        updated = Map.merge(data, updates)
        :ets.insert(@table, {character_id, updated})
        :ok
    end
  end

  @doc """
  Clears all players (e.g., during shutdown).
  """
  def clear do
    :ets.delete_all_objects(@table)
    :ok
  end
end