"""Tests for capnp_stubgen.emitter."""

from capnp_stubgen.emitter import Emitter


class TestEmitterBasic:
    def test_header(self):
        e = Emitter("test.capnp")
        content = e.render()
        assert '"""Auto-generated type stub for test.capnp."""' in content
        assert "from __future__ import annotations" in content

    def test_class_definition(self):
        e = Emitter("test.capnp")
        e.begin_class("Foo")
        e.add_field("bar", "int")
        e.end_class()
        content = e.render()
        assert "class Foo:" in content
        assert "    bar: int" in content

    def test_type_alias(self):
        e = Emitter("test.capnp")
        e.add_typing_import("Literal")
        e.add_type_alias("Gender", 'Literal["male", "female"]')
        content = e.render()
        assert 'Gender = Literal["male", "female"]' in content
        assert "from typing import Literal" in content

    def test_method(self):
        e = Emitter("test.capnp")
        e.add_method("foo", params=["self", "x: int"], return_type="str")
        content = e.render()
        assert "def foo(self, x: int) -> str: ..." in content

    def test_static_method(self):
        e = Emitter("test.capnp")
        e.add_static_method("create", params=["x: int"], return_type="Foo")
        content = e.render()
        assert "@staticmethod" in content
        assert "def create(x: int) -> Foo: ..." in content

    def test_imports_grouped(self):
        e = Emitter("test.capnp")
        e.add_typing_import("Literal")
        e.add_typing_import("Sequence", "collections.abc")
        e.add_typing_import("Iterator", "collections.abc")
        content = e.render()
        # typing imports grouped
        assert "from typing import Literal" in content
        # collections.abc imports grouped
        assert "from collections.abc import Iterator, Sequence" in content

    def test_nested_classes(self):
        e = Emitter("test.capnp")
        e.begin_class("Outer")
        e.add_field("x", "int")
        e.begin_class("Inner")
        e.add_field("y", "str")
        e.end_class()
        e.end_class()
        content = e.render()
        assert "class Outer:" in content
        assert "    x: int" in content
        assert "    class Inner:" in content
        assert "        y: str" in content

    def test_decorators(self):
        e = Emitter("test.capnp")
        e.add_decorator("overload")
        e.add_method("foo", params=["x: int"], return_type="str")
        content = e.render()
        assert "@overload" in content
        assert "def foo(x: int) -> str: ..." in content