bc_utils

defmodule BCUtils.Errors do
  @moduledoc """
    Standardized error handling for BCUtils modules.

    This module provides common error types and utilities for consistent
    error handling across the BCUtils library.

  ## Error Types

  - `BCUtils.Errors.InvalidInputError` - For invalid input parameters
  - `BCUtils.Errors.ConfigurationError` - For configuration-related errors
  - `BCUtils.Errors.TerminalError` - For terminal/display-related errors
  - `BCUtils.Errors.ProcessError` - For process/system-related errors

  """

  @type error_context :: map()
  @type error_reason :: String.t()

  defmodule InvalidInputError do
    @moduledoc "Error for invalid input parameters"

    defexception [:message, :context, :received_value]

    @type t :: %__MODULE__{
            message: String.t(),
            context: map(),
            received_value: any()
          }

    def new(message, context \\ %{}) do
      %__MODULE__{
        message: message,
        context: context,
        received_value: Map.get(context, :received)
      }
    end
  end

  defmodule ConfigurationError do
    @moduledoc "Error for configuration-related issues"

    defexception [:message, :config_key, :expected_type, :received_value]

    @type t :: %__MODULE__{
            message: String.t(),
            config_key: atom() | String.t(),
            expected_type: String.t(),
            received_value: any()
          }

    def new(message, config_key, expected_type \\ nil, received_value \\ nil) do
      %__MODULE__{
        message: message,
        config_key: config_key,
        expected_type: expected_type,
        received_value: received_value
      }
    end
  end

  defmodule TerminalError do
    @moduledoc "Error for terminal/display-related issues"

    defexception [:message, :terminal_capability, :fallback_available]

    @type t :: %__MODULE__{
            message: String.t(),
            terminal_capability: String.t(),
            fallback_available: boolean()
          }

    def new(message, capability \\ "unknown", fallback_available \\ false) do
      %__MODULE__{
        message: message,
        terminal_capability: capability,
        fallback_available: fallback_available
      }
    end
  end

  defmodule ProcessError do
    @moduledoc "Error for process/system-related issues"

    defexception [:message, :process_info, :system_info]

    @type t :: %__MODULE__{
            message: String.t(),
            process_info: map(),
            system_info: map()
          }

    def new(message, process_info \\ %{}, system_info \\ %{}) do
      %__MODULE__{
        message: message,
        process_info: process_info,
        system_info: system_info
      }
    end
  end

  @doc """
  Extracts error message from any BCUtils error struct.

  ## Examples

      iex> error = BCUtils.Errors.InvalidInputError.new("Bad parameter")
      iex> BCUtils.Errors.message(error)
      "Bad parameter"
  """
  @spec message(struct()) :: String.t()
  def message(%{message: msg}) when is_binary(msg), do: msg
  def message(error), do: inspect(error)

  @doc """
  Creates a formatted error report for logging or debugging.

  ## Examples

      iex> error = BCUtils.Errors.ConfigurationError.new("Invalid config", :theme, "atom", "string")
      iex> BCUtils.Errors.format_error(error)
      "ConfigurationError: Invalid config\\nConfig Key: theme\\nExpected: atom\\nReceived: \\"string\\""
  """
  @spec format_error(struct()) :: String.t()
  def format_error(%InvalidInputError{} = error) do
    base = "InvalidInput: #{error.message}"

    context_info =
      if map_size(error.context) > 0 do
        "\\nContext: #{inspect(error.context)}"
      else
        ""
      end

    base <> context_info
  end

  def format_error(%ConfigurationError{} = error) do
    base = "ConfigurationError: #{error.message}"
    key_info = if error.config_key, do: "\\nConfig Key: #{error.config_key}", else: ""
    type_info = if error.expected_type, do: "\\nExpected: #{error.expected_type}", else: ""

    value_info =
      if error.received_value, do: "\\nReceived: #{inspect(error.received_value)}", else: ""

    base <> key_info <> type_info <> value_info
  end

  def format_error(%TerminalError{} = error) do
    base = "TerminalError: #{error.message}"
    capability_info = "\\nCapability: #{error.terminal_capability}"
    fallback_info = "\\nFallback Available: #{error.fallback_available}"
    base <> capability_info <> fallback_info
  end

  def format_error(%ProcessError{} = error) do
    base = "ProcessError: #{error.message}"

    process_info =
      if map_size(error.process_info) > 0 do
        "\\nProcess Info: #{inspect(error.process_info)}"
      else
        ""
      end

    system_info =
      if map_size(error.system_info) > 0 do
        "\\nSystem Info: #{inspect(error.system_info)}"
      else
        ""
      end

    base <> process_info <> system_info
  end

  def format_error(error), do: inspect(error)

  @doc """
  Wraps a function result in an ok/error tuple if not already wrapped.

  ## Examples

      iex> BCUtils.Errors.wrap_result("success")
      {:ok, "success"}
      
      iex> BCUtils.Errors.wrap_result({:error, "failed"})
      {:error, "failed"}
  """
  @spec wrap_result(any()) :: {:ok, any()} | {:error, any()}
  def wrap_result({:ok, _} = result), do: result
  def wrap_result({:error, _} = result), do: result
  def wrap_result(result), do: {:ok, result}
end