module FFI
  module Library
    type convention = :default | :stdcall
    type ffi_lib_flag = :global | :local | :lazy | :now
    type ffi_lib_type = ffi_auto_type | singleton(Struct)

    CURRENT_PROCESS: current_process
    LIBC: String
    FlagsMap: Hash[ffi_lib_flag, Integer]

    def self.extended: ...

    def attach_function: (           _ToS func, Array[ffi_lib_type] args,  ffi_lib_type? returns, ?blocking: boolish, ?convention: convention, ?enums: Enums, ?type_map: type_map) -> (Function | VariadicInvoker)
                       | (_ToS name, _ToS func, Array[ffi_lib_type] args, ?ffi_lib_type? returns, ?blocking: boolish, ?convention: convention, ?enums: Enums, ?type_map: type_map) -> (Function | VariadicInvoker)
    def attach_variable: (?_ToS mname, _ToS cname, ffi_lib_type type) -> DynamicLibrary::Symbol
    def attached_functions: () -> Hash[Symbol, Function | VariadicInvoker]
    def attached_variables: () -> Hash[Symbol, Type | singleton(Struct)]

    def bitmask: (?Type native_type, Symbol name, Array[Symbol | Integer] values) -> Bitmask
               | (?Type native_type, *Symbol | Integer args) -> Bitmask
               | (?Type native_type, Array[Symbol | Integer] values) -> Bitmask
    def enum: (?Type native_type, Symbol name, Array[Symbol | Integer] values) -> Enum
            | (?Type native_type, *Symbol | Integer args) -> Enum
            | (?Type native_type, Array[Symbol | Integer] values) -> Enum
    def enum_type: (Symbol name) -> Enum?
    def enum_for: (Symbol name) -> Integer?

    def callback: (?Symbol name, Array[ffi_lib_type] params, ffi_lib_type ret) -> CallbackInfo
    def ffi_convention: (?convention? convention) -> convention
    def ffi_lib: (*_ToS names) -> Array[DynamicLibrary]
    def ffi_lib_flags: (*ffi_lib_flag flags) -> Integer
    def ffi_libraries: () -> Array[DynamicLibrary]
    def find_type: (ffi_lib_type t) -> Type
    def freeze: () -> void
    def function_names: (_ToS name, Array[Type | singleton(Struct)] arg_types) -> Array[String]
    def typedef: [T < Type] (T old, Symbol | DataConverter add, ?untyped) -> T
               | (Symbol old, Symbol add, ?untyped) -> (Type | Enum)
               | [X < DataConverter[N, R, C], N, R, C] (X old, Symbol add, ?untyped) -> Type::Mapped[X, N, R, C]
               | (:enum old, Array[Symbol | Integer] add, ?untyped) -> Enum
               | (:enum old, Symbol | Type add, Array[Symbol | Integer] info) -> Enum
  end
end