defmodule CCXT.Position do
  @moduledoc """
  Unified derivatives position data.

  Represents an open position on a derivatives exchange (futures, swaps, options).

  ## Fields

    * `id` - Position ID
    * `symbol` - Unified symbol (e.g., "BTC/USDT:USDT")
    * `timestamp` - Last update time in milliseconds
    * `datetime` - ISO 8601 datetime string
    * `side` - "long" or "short"
    * `contracts` - Number of contracts
    * `contract_size` - Size of one contract
    * `notional` - Position notional value
    * `leverage` - Current leverage
    * `unrealized_pnl` - Unrealized profit/loss
    * `realized_pnl` - Realized profit/loss
    * `collateral` - Collateral amount
    * `entry_price` - Average entry price
    * `mark_price` - Current mark price
    * `liquidation_price` - Estimated liquidation price
    * `margin_mode` - "cross" or "isolated"
    * `hedged` - Whether position is in hedge mode
    * `maintenance_margin` - Required maintenance margin
    * `maintenance_margin_percentage` - Maintenance margin as percentage
    * `initial_margin` - Required initial margin
    * `initial_margin_percentage` - Initial margin as percentage
    * `margin_ratio` - Current margin ratio
    * `last_update_timestamp` - Last update timestamp
    * `last_price` - Last traded price
    * `stop_loss_price` - Stop loss price
    * `take_profit_price` - Take profit price
    * `percentage` - Percentage PnL
    * `margin` - Position margin
    * `info` - Raw exchange response

  """

  import JSONSpec, only: [schema: 2]

  @type t :: %__MODULE__{
          id: String.t() | nil,
          symbol: String.t() | nil,
          timestamp: integer() | nil,
          datetime: String.t() | nil,
          side: String.t() | nil,
          contracts: number() | nil,
          contract_size: number() | nil,
          notional: number() | nil,
          leverage: number() | nil,
          unrealized_pnl: number() | nil,
          realized_pnl: number() | nil,
          collateral: number() | nil,
          entry_price: number() | nil,
          mark_price: number() | nil,
          liquidation_price: number() | nil,
          margin_mode: String.t() | nil,
          hedged: boolean() | nil,
          maintenance_margin: number() | nil,
          maintenance_margin_percentage: number() | nil,
          initial_margin: number() | nil,
          initial_margin_percentage: number() | nil,
          margin_ratio: number() | nil,
          last_update_timestamp: integer() | nil,
          last_price: number() | nil,
          stop_loss_price: number() | nil,
          take_profit_price: number() | nil,
          percentage: number() | nil,
          margin: number() | nil,
          info: map() | nil
        }

  defstruct [
    :id,
    :symbol,
    :timestamp,
    :datetime,
    :side,
    :contracts,
    :contract_size,
    :notional,
    :leverage,
    :unrealized_pnl,
    :realized_pnl,
    :collateral,
    :entry_price,
    :mark_price,
    :liquidation_price,
    :margin_mode,
    :hedged,
    :maintenance_margin,
    :maintenance_margin_percentage,
    :initial_margin,
    :initial_margin_percentage,
    :margin_ratio,
    :last_update_timestamp,
    :last_price,
    :stop_loss_price,
    :take_profit_price,
    :percentage,
    :margin,
    :info
  ]

  @doc "Returns true if the position is long."
  @spec long?(t()) :: boolean()
  def long?(%__MODULE__{side: "long"}), do: true
  def long?(%__MODULE__{}), do: false

  @doc "Returns true if the position is short."
  @spec short?(t()) :: boolean()
  def short?(%__MODULE__{side: "short"}), do: true
  def short?(%__MODULE__{}), do: false

  @doc "Returns true if the position has positive unrealized PnL."
  @spec profitable?(t()) :: boolean()
  def profitable?(%__MODULE__{unrealized_pnl: pnl}) when is_number(pnl), do: pnl > 0
  def profitable?(%__MODULE__{}), do: false

  @json_schema schema(
                 %{
                   id: String.t() | nil,
                   symbol: String.t() | nil,
                   timestamp: integer() | nil,
                   datetime: String.t() | nil,
                   side: String.t() | nil,
                   contracts: number() | nil,
                   contract_size: number() | nil,
                   notional: number() | nil,
                   leverage: number() | nil,
                   unrealized_pnl: number() | nil,
                   realized_pnl: number() | nil,
                   collateral: number() | nil,
                   entry_price: number() | nil,
                   mark_price: number() | nil,
                   liquidation_price: number() | nil,
                   margin_mode: String.t() | nil,
                   hedged: boolean() | nil,
                   maintenance_margin: number() | nil,
                   maintenance_margin_percentage: number() | nil,
                   initial_margin: number() | nil,
                   initial_margin_percentage: number() | nil,
                   margin_ratio: number() | nil,
                   last_update_timestamp: integer() | nil,
                   last_price: number() | nil,
                   stop_loss_price: number() | nil,
                   take_profit_price: number() | nil,
                   percentage: number() | nil,
                   margin: number() | nil,
                   info: map() | nil
                 },
                 doc: [
                   id: "Position ID",
                   symbol: "Unified symbol (e.g., BTC/USDT:USDT)",
                   timestamp: "Last update time in milliseconds",
                   datetime: "ISO 8601 datetime string",
                   side: "long or short",
                   contracts: "Number of contracts",
                   contract_size: "Size of one contract",
                   notional: "Position notional value",
                   leverage: "Current leverage",
                   unrealized_pnl: "Unrealized profit/loss",
                   realized_pnl: "Realized profit/loss",
                   collateral: "Collateral amount",
                   entry_price: "Average entry price",
                   mark_price: "Current mark price",
                   liquidation_price: "Estimated liquidation price",
                   margin_mode: "cross or isolated",
                   hedged: "Whether position is in hedge mode",
                   maintenance_margin: "Required maintenance margin",
                   maintenance_margin_percentage: "Maintenance margin as percentage",
                   initial_margin: "Required initial margin",
                   initial_margin_percentage: "Initial margin as percentage",
                   margin_ratio: "Current margin ratio",
                   last_update_timestamp: "Last update timestamp",
                   last_price: "Last traded price",
                   stop_loss_price: "Stop loss price",
                   take_profit_price: "Take profit price",
                   percentage: "Percentage PnL",
                   margin: "Position margin",
                   info: "Raw exchange response"
                 ]
               )

  @doc "JSON Schema for the Position unified type."
  @spec schema() :: map()
  def schema, do: @json_schema
end