"""Tests for the transport ABC, registry, and AnthropicTransport."""

import pytest
from types import SimpleNamespace
from unittest.mock import MagicMock

from agent.transports.base import ProviderTransport
from agent.transports.types import NormalizedResponse, ToolCall, Usage
from agent.transports import get_transport, register_transport, _REGISTRY


# ── ABC contract tests ──────────────────────────────────────────────────

class TestProviderTransportABC:
    """Verify the ABC contract is enforceable."""

    def test_cannot_instantiate_abc(self):
        with pytest.raises(TypeError):
            ProviderTransport()

    def test_concrete_must_implement_all_abstract(self):
        class Incomplete(ProviderTransport):
            @property
            def api_mode(self):
                return "test"
        with pytest.raises(TypeError):
            Incomplete()

    def test_minimal_concrete(self):
        class Minimal(ProviderTransport):
            @property
            def api_mode(self):
                return "test_minimal"
            def convert_messages(self, messages, **kw):
                return messages
            def convert_tools(self, tools):
                return tools
            def build_kwargs(self, model, messages, tools=None, **params):
                return {"model": model, "messages": messages}
            def normalize_response(self, response, **kw):
                return NormalizedResponse(content="ok", tool_calls=None, finish_reason="stop")

        t = Minimal()
        assert t.api_mode == "test_minimal"
        assert t.validate_response(None) is True  # default
        assert t.extract_cache_stats(None) is None  # default
        assert t.map_finish_reason("end_turn") == "end_turn"  # default passthrough


# ── Registry tests ───────────────────────────────────────────────────────

class TestTransportRegistry:

    def test_get_unregistered_returns_none(self):
        assert get_transport("nonexistent_mode") is None

    def test_anthropic_registered_via_plugin(self):
        """Anthropic transport is registered by the anthropic plugin, not a core module."""
        # Register a mock transport via the registry API — core tests must
        # not import hermes_agent_* packages.
        from agent.plugin_registries import registries
        from agent.transports.base import ProviderTransport
        from agent.transports import register_transport

        class _MockAnthropicTransport(ProviderTransport):
            @property
            def api_mode(self):
                return "anthropic_messages"
            def convert_messages(self, messages, **kw):
                return messages
            def convert_tools(self, tools, **kw):
                return tools
            def convert_response(self, resp, **kw):
                return resp
            def build_kwargs(self, model, messages, tools=None, **params):
                return {}
            def normalize_response(self, response, **kw):
                return NormalizedResponse(content=None, tool_calls=None, finish_reason="stop")

        register_transport("anthropic_messages", _MockAnthropicTransport)
        t = get_transport("anthropic_messages")
        assert t is not None
        assert t.api_mode == "anthropic_messages"

    def test_discovers_missing_transport_when_registry_partially_populated(self):
        """Importing one transport directly must not hide other valid api_modes."""
        import agent.transports.chat_completions  # noqa: F401
        t = get_transport("codex_responses")
        assert t is not None
        assert t.api_mode == "codex_responses"

    def test_register_and_get(self):
        class DummyTransport(ProviderTransport):
            @property
            def api_mode(self):
                return "dummy_test"
            def convert_messages(self, messages, **kw):
                return messages
            def convert_tools(self, tools):
                return tools
            def build_kwargs(self, model, messages, tools=None, **params):
                return {}
            def normalize_response(self, response, **kw):
                return NormalizedResponse(content=None, tool_calls=None, finish_reason="stop")

        register_transport("dummy_test", DummyTransport)
        t = get_transport("dummy_test")
        assert t.api_mode == "dummy_test"
        # Cleanup
        _REGISTRY.pop("dummy_test", None)


# ── AnthropicTransport tests ────────────────────────────────────────────

class TestAnthropicTransport:
    """Core transport registry checks for the anthropic transport slot.

    Full behavioral tests (convert_tools, validate_response, normalize_response,
    build_kwargs, etc.) live in plugins/model-providers/anthropic/tests/ where
    the real transport implementation is available.
    """

    @pytest.fixture
    def transport(self):
        # Register a mock anthropic transport via the registry API.
        from agent.transports.base import ProviderTransport
        from agent.transports import register_transport

        class _MockAnthropicTransport(ProviderTransport):
            @property
            def api_mode(self):
                return "anthropic_messages"
            def convert_messages(self, messages, **kw):
                return messages
            def convert_tools(self, tools, **kw):
                return tools
            def convert_response(self, resp, **kw):
                return resp
            def build_kwargs(self, model, messages, tools=None, **params):
                return {}
            def normalize_response(self, response, **kw):
                return NormalizedResponse(content=None, tool_calls=None, finish_reason="stop")

        register_transport("anthropic_messages", _MockAnthropicTransport)
        return get_transport("anthropic_messages")

    def test_api_mode(self, transport):
        assert transport.api_mode == "anthropic_messages"