"""Contract tests for get_database_info MCP tool."""

from pathlib import Path

import pytest

from xer_mcp.db import db


@pytest.fixture(autouse=True)
def setup_db():
    """Reset database state for each test."""
    if db.is_initialized:
        db.close()
    yield
    if db.is_initialized:
        db.close()


class TestGetDatabaseInfoContract:
    """Contract tests verifying get_database_info tool interface."""

    async def test_get_database_info_returns_current_database(
        self, tmp_path: Path, sample_xer_single_project: Path
    ) -> None:
        """get_database_info returns info about currently loaded database."""
        from xer_mcp.tools.get_database_info import get_database_info
        from xer_mcp.tools.load_xer import load_xer

        db_file = tmp_path / "schedule.db"
        await load_xer(
            file_path=str(sample_xer_single_project),
            db_path=str(db_file),
        )

        result = await get_database_info()

        assert "database" in result
        assert result["database"]["db_path"] == str(db_file)
        assert result["database"]["is_persistent"] is True

    async def test_get_database_info_error_when_no_database(self) -> None:
        """get_database_info returns error when no database loaded."""
        from xer_mcp.tools.get_database_info import get_database_info

        # Ensure database is not initialized
        if db.is_initialized:
            db.close()

        result = await get_database_info()

        assert "error" in result
        assert result["error"]["code"] == "NO_FILE_LOADED"

    async def test_get_database_info_includes_schema(
        self, tmp_path: Path, sample_xer_single_project: Path
    ) -> None:
        """get_database_info includes schema information."""
        from xer_mcp.tools.get_database_info import get_database_info
        from xer_mcp.tools.load_xer import load_xer

        db_file = tmp_path / "schedule.db"
        await load_xer(
            file_path=str(sample_xer_single_project),
            db_path=str(db_file),
        )

        result = await get_database_info()

        assert "schema" in result["database"]
        assert "tables" in result["database"]["schema"]

    async def test_get_database_info_includes_loaded_at(
        self, tmp_path: Path, sample_xer_single_project: Path
    ) -> None:
        """get_database_info includes loaded_at timestamp."""
        from xer_mcp.tools.get_database_info import get_database_info
        from xer_mcp.tools.load_xer import load_xer

        db_file = tmp_path / "schedule.db"
        await load_xer(
            file_path=str(sample_xer_single_project),
            db_path=str(db_file),
        )

        result = await get_database_info()

        assert "loaded_at" in result["database"]
        # Should be ISO format timestamp
        assert "T" in result["database"]["loaded_at"]

    async def test_get_database_info_includes_source_file(
        self, tmp_path: Path, sample_xer_single_project: Path
    ) -> None:
        """get_database_info includes source XER file path."""
        from xer_mcp.tools.get_database_info import get_database_info
        from xer_mcp.tools.load_xer import load_xer

        db_file = tmp_path / "schedule.db"
        await load_xer(
            file_path=str(sample_xer_single_project),
            db_path=str(db_file),
        )

        result = await get_database_info()

        assert result["database"]["source_file"] == str(sample_xer_single_project)

    async def test_get_database_info_for_memory_database(
        self, sample_xer_single_project: Path
    ) -> None:
        """get_database_info works for in-memory database."""
        from xer_mcp.tools.get_database_info import get_database_info
        from xer_mcp.tools.load_xer import load_xer

        await load_xer(file_path=str(sample_xer_single_project))

        result = await get_database_info()

        assert "database" in result
        assert result["database"]["db_path"] == ":memory:"
        assert result["database"]["is_persistent"] is False


class TestGetDatabaseInfoToolSchema:
    """Tests for MCP tool schema."""

    async def test_get_database_info_tool_registered(self) -> None:
        """get_database_info tool is registered with MCP server."""
        from xer_mcp.server import list_tools

        tools = await list_tools()
        tool_names = [t.name for t in tools]
        assert "get_database_info" in tool_names

    async def test_get_database_info_tool_has_empty_input_schema(self) -> None:
        """get_database_info tool has no required inputs."""
        from xer_mcp.server import list_tools

        tools = await list_tools()
        tool = next(t for t in tools if t.name == "get_database_info")
        # Should have empty or no required properties
        assert "required" not in tool.inputSchema or len(tool.inputSchema.get("required", [])) == 0