"""Integration tests for native tool calling functionality.

These tests verify that agents can use native function calling
when the LLM supports it, across multiple providers.
"""

from __future__ import annotations

from collections.abc import Generator
import os
import threading
import time
from collections import Counter
from unittest.mock import Mock, patch

import pytest
from pydantic import BaseModel, Field

from crewai import Agent, Crew, Task
from crewai.events import crewai_event_bus
from crewai.hooks import register_after_tool_call_hook, register_before_tool_call_hook
from crewai.hooks.tool_hooks import ToolCallHookContext
from crewai.llm import LLM
from crewai.tools.base_tool import BaseTool


class CalculatorInput(BaseModel):
    """Input schema for calculator tool."""

    expression: str = Field(description="Mathematical expression to evaluate")


class CalculatorTool(BaseTool):
    """A calculator tool that performs mathematical calculations."""

    name: str = "calculator"
    description: str = "Perform mathematical calculations. Use this for any math operations."
    args_schema: type[BaseModel] = CalculatorInput

    def _run(self, expression: str) -> str:
        """Execute the calculation."""
        try:
            # Safe evaluation for basic math
            result = eval(expression)  # noqa: S307
            return f"The result of {expression} is {result}"
        except Exception as e:
            return f"Error calculating {expression}: {e}"


class WeatherInput(BaseModel):
    """Input schema for weather tool."""

    location: str = Field(description="City name to get weather for")


class WeatherTool(BaseTool):
    """A mock weather tool for testing."""

    name: str = "get_weather"
    description: str = "Get the current weather for a location"
    args_schema: type[BaseModel] = WeatherInput

    def _run(self, location: str) -> str:
        """Get weather (mock implementation)."""
        return f"The weather in {location} is sunny with a temperature of 72°F"

class FailingTool(BaseTool):
    """A tool that always fails."""
    name: str = "failing_tool"
    description: str = "This tool always fails"
    def _run(self) -> str:
        raise Exception("This tool always fails")


class LocalSearchInput(BaseModel):
    query: str = Field(description="Search query")


class ParallelProbe:
    """Thread-safe in-memory recorder for tool execution windows."""

    _lock = threading.Lock()
    _windows: list[tuple[str, float, float]] = []

    @classmethod
    def reset(cls) -> None:
        with cls._lock:
            cls._windows = []

    @classmethod
    def record(cls, tool_name: str, start: float, end: float) -> None:
        with cls._lock:
            cls._windows.append((tool_name, start, end))

    @classmethod
    def windows(cls) -> list[tuple[str, float, float]]:
        with cls._lock:
            return list(cls._windows)


def _parallel_prompt() -> str:
    return (
        "This is a tool-calling compliance test. "
        "In your next assistant turn, emit exactly 3 tool calls in the same response (parallel tool calls), in this order: "
        "1) parallel_local_search_one(query='latest OpenAI model release notes'), "
        "2) parallel_local_search_two(query='latest Anthropic model release notes'), "
        "3) parallel_local_search_three(query='latest Gemini model release notes'). "
        "Do not call any other tools and do not answer before those 3 tool calls are emitted. "
        "After the tool results return, provide a one paragraph summary."
    )


def _max_concurrency(windows: list[tuple[str, float, float]]) -> int:
    points: list[tuple[float, int]] = []
    for _, start, end in windows:
        points.append((start, 1))
        points.append((end, -1))
    points.sort(key=lambda p: (p[0], p[1]))

    current = 0
    maximum = 0
    for _, delta in points:
        current += delta
        if current > maximum:
            maximum = current
    return maximum


def _assert_tools_overlapped() -> None:
    windows = ParallelProbe.windows()
    local_windows = [
        w
        for w in windows
        if w[0].startswith("parallel_local_search_")
    ]

    assert len(local_windows) >= 3, f"Expected at least 3 local tool calls, got {len(local_windows)}"
    assert _max_concurrency(local_windows) >= 2, "Expected overlapping local tool executions"


@pytest.fixture
def calculator_tool() -> CalculatorTool:
    """Create a calculator tool for testing."""
    return CalculatorTool()


@pytest.fixture
def weather_tool() -> WeatherTool:
    """Create a weather tool for testing."""
    return WeatherTool()

@pytest.fixture
def failing_tool() -> BaseTool:
    """Create a weather tool for testing."""
    return FailingTool(

    )


@pytest.fixture
def parallel_tools() -> list[BaseTool]:
    """Create local tools used to verify native parallel execution deterministically."""

    class ParallelLocalSearchOne(BaseTool):
        name: str = "parallel_local_search_one"
        description: str = "Local search tool #1 for concurrency testing."
        args_schema: type[BaseModel] = LocalSearchInput

        def _run(self, query: str) -> str:
            start = time.perf_counter()
            time.sleep(1.0)
            end = time.perf_counter()
            ParallelProbe.record(self.name, start, end)
            return f"[one] {query}"

    class ParallelLocalSearchTwo(BaseTool):
        name: str = "parallel_local_search_two"
        description: str = "Local search tool #2 for concurrency testing."
        args_schema: type[BaseModel] = LocalSearchInput

        def _run(self, query: str) -> str:
            start = time.perf_counter()
            time.sleep(1.0)
            end = time.perf_counter()
            ParallelProbe.record(self.name, start, end)
            return f"[two] {query}"

    class ParallelLocalSearchThree(BaseTool):
        name: str = "parallel_local_search_three"
        description: str = "Local search tool #3 for concurrency testing."
        args_schema: type[BaseModel] = LocalSearchInput

        def _run(self, query: str) -> str:
            start = time.perf_counter()
            time.sleep(1.0)
            end = time.perf_counter()
            ParallelProbe.record(self.name, start, end)
            return f"[three] {query}"

    return [
        ParallelLocalSearchOne(),
        ParallelLocalSearchTwo(),
        ParallelLocalSearchThree(),
    ]


def _attach_parallel_probe_handler() -> None:
    @crewai_event_bus.on(ToolUsageFinishedEvent)
    def _capture_tool_window(_source, event: ToolUsageFinishedEvent):
        if not event.tool_name.startswith("parallel_local_search_"):
            return
        ParallelProbe.record(
            event.tool_name,
            event.started_at.timestamp(),
            event.finished_at.timestamp(),
        )

# =============================================================================
# OpenAI Provider Tests
# =============================================================================


class TestOpenAINativeToolCalling:
    """Tests for native tool calling with OpenAI models."""

    @pytest.mark.vcr()
    def test_openai_agent_with_native_tool_calling(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test OpenAI agent can use native tool calling."""
        agent = Agent(
            role="Math Assistant",
            goal="Help users with mathematical calculations",
            backstory="You are a helpful math assistant.",
            tools=[calculator_tool],
            llm=LLM(model="gpt-4o-mini"),
            verbose=False,
            max_iter=3,
        )

        task = Task(
            description="Calculate what is 15 * 8",
            expected_output="The result of the calculation",
            agent=agent,
        )

        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()

        assert result is not None
        assert result.raw is not None
        assert "120" in str(result.raw)

    def test_openai_agent_kickoff_with_tools_mocked(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test OpenAI agent kickoff with mocked LLM call."""
        llm = LLM(model="gpt-5-nano")

        with patch.object(llm, "call", return_value="The answer is 120.") as mock_call:
            agent = Agent(
                role="Math Assistant",
                goal="Calculate math",
                backstory="You calculate.",
                tools=[calculator_tool],
                llm=llm,
                verbose=False,
            )

            task = Task(
                description="Calculate 15 * 8",
                expected_output="Result",
                agent=agent,
            )

            crew = Crew(agents=[agent], tasks=[task])
            result = crew.kickoff()

            assert mock_call.called
            assert result is not None

    @pytest.mark.vcr()
    @pytest.mark.timeout(180)
    def test_openai_parallel_native_tool_calling_test_crew(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="gpt-5-nano", temperature=1),
            verbose=False,
            max_iter=3,
        )
        task = Task(
            description=_parallel_prompt(),
            expected_output="A one sentence summary of both tool outputs",
            agent=agent,
        )
        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()
        assert result is not None
        _assert_tools_overlapped()

    @pytest.mark.vcr()
    @pytest.mark.timeout(180)
    def test_openai_parallel_native_tool_calling_test_agent_kickoff(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="gpt-4o-mini"),
            verbose=False,
            max_iter=3,
        )
        result = agent.kickoff(_parallel_prompt())
        assert result is not None
        _assert_tools_overlapped()

    @pytest.mark.vcr()
    @pytest.mark.timeout(180)
    def test_openai_parallel_native_tool_calling_tool_hook_parity_crew(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        hook_calls: dict[str, list[dict[str, str]]] = {"before": [], "after": []}

        def before_hook(context: ToolCallHookContext) -> bool | None:
            if context.tool_name.startswith("parallel_local_search_"):
                hook_calls["before"].append(
                    {
                        "tool_name": context.tool_name,
                        "query": str(context.tool_input.get("query", "")),
                    }
                )
            return None

        def after_hook(context: ToolCallHookContext) -> str | None:
            if context.tool_name.startswith("parallel_local_search_"):
                hook_calls["after"].append(
                    {
                        "tool_name": context.tool_name,
                        "query": str(context.tool_input.get("query", "")),
                    }
                )
            return None

        register_before_tool_call_hook(before_hook)
        register_after_tool_call_hook(after_hook)

        try:
            agent = Agent(
                role="Parallel Tool Agent",
                goal="Use both tools exactly as instructed",
                backstory="You follow tool instructions precisely.",
                tools=parallel_tools,
                llm=LLM(model="gpt-5-nano", temperature=1),
                verbose=False,
                max_iter=3,
            )
            task = Task(
                description=_parallel_prompt(),
                expected_output="A one sentence summary of both tool outputs",
                agent=agent,
            )
            crew = Crew(agents=[agent], tasks=[task])
            result = crew.kickoff()

            assert result is not None
            _assert_tools_overlapped()

            before_names = [call["tool_name"] for call in hook_calls["before"]]
            after_names = [call["tool_name"] for call in hook_calls["after"]]
            assert len(before_names) >= 3, "Expected before hooks for all parallel calls"
            assert Counter(before_names) == Counter(after_names)
            assert all(call["query"] for call in hook_calls["before"])
            assert all(call["query"] for call in hook_calls["after"])
        finally:
            from crewai.hooks import (
                unregister_after_tool_call_hook,
                unregister_before_tool_call_hook,
            )

            unregister_before_tool_call_hook(before_hook)
            unregister_after_tool_call_hook(after_hook)

    @pytest.mark.vcr()
    @pytest.mark.timeout(180)
    def test_openai_parallel_native_tool_calling_tool_hook_parity_agent_kickoff(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        hook_calls: dict[str, list[dict[str, str]]] = {"before": [], "after": []}

        def before_hook(context: ToolCallHookContext) -> bool | None:
            if context.tool_name.startswith("parallel_local_search_"):
                hook_calls["before"].append(
                    {
                        "tool_name": context.tool_name,
                        "query": str(context.tool_input.get("query", "")),
                    }
                )
            return None

        def after_hook(context: ToolCallHookContext) -> str | None:
            if context.tool_name.startswith("parallel_local_search_"):
                hook_calls["after"].append(
                    {
                        "tool_name": context.tool_name,
                        "query": str(context.tool_input.get("query", "")),
                    }
                )
            return None

        register_before_tool_call_hook(before_hook)
        register_after_tool_call_hook(after_hook)

        try:
            agent = Agent(
                role="Parallel Tool Agent",
                goal="Use both tools exactly as instructed",
                backstory="You follow tool instructions precisely.",
                tools=parallel_tools,
                llm=LLM(model="gpt-5-nano", temperature=1),
                verbose=False,
                max_iter=3,
            )
            result = agent.kickoff(_parallel_prompt())

            assert result is not None
            _assert_tools_overlapped()

            before_names = [call["tool_name"] for call in hook_calls["before"]]
            after_names = [call["tool_name"] for call in hook_calls["after"]]
            assert len(before_names) >= 3, "Expected before hooks for all parallel calls"
            assert Counter(before_names) == Counter(after_names)
            assert all(call["query"] for call in hook_calls["before"])
            assert all(call["query"] for call in hook_calls["after"])
        finally:
            from crewai.hooks import (
                unregister_after_tool_call_hook,
                unregister_before_tool_call_hook,
            )

            unregister_before_tool_call_hook(before_hook)
            unregister_after_tool_call_hook(after_hook)


# =============================================================================
# Anthropic Provider Tests
# =============================================================================
class TestAnthropicNativeToolCalling:
    """Tests for native tool calling with Anthropic models."""

    @pytest.fixture(autouse=True)
    def mock_anthropic_api_key(self):
        """Mock ANTHROPIC_API_KEY for tests."""
        if "ANTHROPIC_API_KEY" not in os.environ:
            with patch.dict(os.environ, {"ANTHROPIC_API_KEY": "test-key"}):
                yield
        else:
            yield

    @pytest.mark.vcr()
    def test_anthropic_agent_with_native_tool_calling(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test Anthropic agent can use native tool calling."""
        agent = Agent(
            role="Math Assistant",
            goal="Help users with mathematical calculations",
            backstory="You are a helpful math assistant.",
            tools=[calculator_tool],
            llm=LLM(model="anthropic/claude-3-5-haiku-20241022"),
            verbose=False,
            max_iter=3,
        )

        task = Task(
            description="Calculate what is 15 * 8",
            expected_output="The result of the calculation",
            agent=agent,
        )

        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()

        assert result is not None
        assert result.raw is not None

    def test_anthropic_agent_kickoff_with_tools_mocked(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test Anthropic agent kickoff with mocked LLM call."""
        llm = LLM(model="anthropic/claude-3-5-haiku-20241022")

        with patch.object(llm, "call", return_value="The answer is 120.") as mock_call:
            agent = Agent(
                role="Math Assistant",
                goal="Calculate math",
                backstory="You calculate.",
                tools=[calculator_tool],
                llm=llm,
                verbose=False,
            )

            task = Task(
                description="Calculate 15 * 8",
                expected_output="Result",
                agent=agent,
            )

            crew = Crew(agents=[agent], tasks=[task])
            result = crew.kickoff()

            assert mock_call.called
            assert result is not None

    @pytest.mark.vcr()
    def test_anthropic_parallel_native_tool_calling_test_crew(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="anthropic/claude-sonnet-4-6"),
            verbose=False,
            max_iter=3,
        )
        task = Task(
            description=_parallel_prompt(),
            expected_output="A one sentence summary of both tool outputs",
            agent=agent,
        )
        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()
        assert result is not None
        _assert_tools_overlapped()

    @pytest.mark.vcr()
    def test_anthropic_parallel_native_tool_calling_test_agent_kickoff(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="anthropic/claude-sonnet-4-6"),
            verbose=False,
            max_iter=3,
        )
        result = agent.kickoff(_parallel_prompt())
        assert result is not None
        _assert_tools_overlapped()


# =============================================================================
# Google/Gemini Provider Tests
# =============================================================================


class TestGeminiNativeToolCalling:
    """Tests for native tool calling with Gemini models."""

    @pytest.fixture(autouse=True)
    def mock_google_api_key(self):
        """Mock GOOGLE_API_KEY for tests."""
        if "GOOGLE_API_KEY" not in os.environ and "GEMINI_API_KEY" not in os.environ:
            with patch.dict(os.environ, {"GOOGLE_API_KEY": "test-key"}):
                yield
        else:
            yield


    @pytest.mark.vcr()
    def test_gemini_agent_with_native_tool_calling(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test Gemini agent can use native tool calling."""

        agent = Agent(
            role="Math Assistant",
            goal="Help users with mathematical calculations",
            backstory="You are a helpful math assistant.",
            tools=[calculator_tool],
            llm=LLM(model="gemini/gemini-2.5-flash"),
        )

        task = Task(
            description="Calculate what is 15 * 8",
            expected_output="The result of the calculation",
            agent=agent,
        )

        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()

        assert result is not None
        assert result.raw is not None

    def test_gemini_agent_kickoff_with_tools_mocked(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test Gemini agent kickoff with mocked LLM call."""
        llm = LLM(model="gemini/gemini-2.5-flash")

        with patch.object(llm, "call", return_value="The answer is 120.") as mock_call:
            agent = Agent(
                role="Math Assistant",
                goal="Calculate math",
                backstory="You calculate.",
                tools=[calculator_tool],
                llm=llm,
                verbose=False,
            )

            task = Task(
                description="Calculate 15 * 8",
                expected_output="Result",
                agent=agent,
            )

            crew = Crew(agents=[agent], tasks=[task])
            result = crew.kickoff()

            assert mock_call.called
            assert result is not None

    @pytest.mark.vcr()
    def test_gemini_parallel_native_tool_calling_test_crew(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="gemini/gemini-2.5-flash"),
            verbose=False,
            max_iter=3,
        )
        task = Task(
            description=_parallel_prompt(),
            expected_output="A one sentence summary of both tool outputs",
            agent=agent,
        )
        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()
        assert result is not None
        _assert_tools_overlapped()

    @pytest.mark.vcr()
    def test_gemini_parallel_native_tool_calling_test_agent_kickoff(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="gemini/gemini-2.5-flash"),
            verbose=False,
            max_iter=3,
        )
        result = agent.kickoff(_parallel_prompt())
        assert result is not None
        _assert_tools_overlapped()


# =============================================================================
# Azure Provider Tests
# =============================================================================


class TestAzureNativeToolCalling:
    """Tests for native tool calling with Azure OpenAI models."""

    @pytest.fixture(autouse=True)
    def mock_azure_env(self):
        """Mock Azure environment variables for tests."""
        env_vars = {
            "AZURE_API_KEY": "test-key",
            "AZURE_API_BASE": "https://test.openai.azure.com",
            "AZURE_API_VERSION": "2024-02-15-preview",
        }
        # Only patch if keys are not already in environment
        if "AZURE_API_KEY" not in os.environ:
            with patch.dict(os.environ, env_vars):
                yield
        else:
            yield

    @pytest.mark.vcr()
    def test_azure_agent_with_native_tool_calling(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test Azure agent can use native tool calling."""
        agent = Agent(
            role="Math Assistant",
            goal="Help users with mathematical calculations",
            backstory="You are a helpful math assistant.",
            tools=[calculator_tool],
            llm=LLM(model="azure/gpt-5-nano"),
            verbose=False,
            max_iter=3,
        )

        task = Task(
            description="Calculate what is 15 * 8",
            expected_output="The result of the calculation",
            agent=agent,
        )

        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()

        assert result is not None
        assert result.raw is not None
        assert "120" in str(result.raw)

    def test_azure_agent_kickoff_with_tools_mocked(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test Azure agent kickoff with mocked LLM call."""
        llm = LLM(
            model="azure/gpt-5-nano",
            api_key="test-key",
            base_url="https://test.openai.azure.com",
        )

        with patch.object(llm, "call", return_value="The answer is 120.") as mock_call:
            agent = Agent(
                role="Math Assistant",
                goal="Calculate math",
                backstory="You calculate.",
                tools=[calculator_tool],
                llm=llm,
                verbose=False,
            )

            task = Task(
                description="Calculate 15 * 8",
                expected_output="Result",
                agent=agent,
            )

            crew = Crew(agents=[agent], tasks=[task])
            result = crew.kickoff()

            assert mock_call.called
            assert result is not None

    @pytest.mark.vcr()
    def test_azure_parallel_native_tool_calling_test_crew(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="azure/gpt-5-nano"),
            verbose=False,
            max_iter=3,
        )
        task = Task(
            description=_parallel_prompt(),
            expected_output="A one sentence summary of both tool outputs",
            agent=agent,
        )
        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()
        assert result is not None
        _assert_tools_overlapped()

    @pytest.mark.vcr()
    def test_azure_parallel_native_tool_calling_test_agent_kickoff(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="azure/gpt-5-nano"),
            verbose=False,
            max_iter=3,
        )
        result = agent.kickoff(_parallel_prompt())
        assert result is not None
        _assert_tools_overlapped()


# =============================================================================
# Bedrock Provider Tests
# =============================================================================


class TestBedrockNativeToolCalling:
    """Tests for native tool calling with AWS Bedrock models."""

    @pytest.fixture(autouse=True)
    def validate_bedrock_credentials_for_live_recording(self):
        """Run Bedrock tests only when explicitly enabled."""
        run_live_bedrock = os.getenv("RUN_BEDROCK_LIVE_TESTS", "false").lower() == "true"

        if not run_live_bedrock:
            pytest.skip(
                "Skipping Bedrock tests by default. "
                "Set RUN_BEDROCK_LIVE_TESTS=true with valid AWS credentials to enable."
            )

        access_key = os.getenv("AWS_ACCESS_KEY_ID", "")
        secret_key = os.getenv("AWS_SECRET_ACCESS_KEY", "")
        if (
            not access_key
            or not secret_key
            or access_key.startswith(("fake-", "test-"))
            or secret_key.startswith(("fake-", "test-"))
        ):
            pytest.skip(
                "Skipping Bedrock tests: valid AWS credentials are required when "
                "RUN_BEDROCK_LIVE_TESTS=true."
            )

        yield

    @pytest.mark.vcr()
    def test_bedrock_agent_kickoff_with_tools_mocked(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test Bedrock agent kickoff with mocked LLM call."""
        llm = LLM(model="bedrock/anthropic.claude-3-haiku-20240307-v1:0")

        agent = Agent(
            role="Math Assistant",
            goal="Calculate math",
            backstory="You calculate.",
            tools=[calculator_tool],
            llm=llm,
            verbose=False,
            max_iter=5,
        )

        task = Task(
            description="Calculate 15 * 8",
            expected_output="Result",
            agent=agent,
        )

        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()

        assert result is not None
        assert result.raw is not None
        assert "120" in str(result.raw)

    @pytest.mark.vcr()
    def test_bedrock_parallel_native_tool_calling_test_crew(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="bedrock/anthropic.claude-3-haiku-20240307-v1:0"),
            verbose=False,
            max_iter=3,
        )
        task = Task(
            description=_parallel_prompt(),
            expected_output="A one sentence summary of both tool outputs",
            agent=agent,
        )
        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()
        assert result is not None
        _assert_tools_overlapped()

    @pytest.mark.vcr()
    def test_bedrock_parallel_native_tool_calling_test_agent_kickoff(
        self, parallel_tools: list[BaseTool]
    ) -> None:
        agent = Agent(
            role="Parallel Tool Agent",
            goal="Use both tools exactly as instructed",
            backstory="You follow tool instructions precisely.",
            tools=parallel_tools,
            llm=LLM(model="bedrock/anthropic.claude-3-haiku-20240307-v1:0"),
            verbose=False,
            max_iter=3,
        )
        result = agent.kickoff(_parallel_prompt())
        assert result is not None
        _assert_tools_overlapped()


# =============================================================================
# Cross-Provider Native Tool Calling Behavior Tests
# =============================================================================


class TestNativeToolCallingBehavior:
    """Tests for native tool calling behavior across providers."""

    def test_supports_function_calling_check(self) -> None:
        """Test that supports_function_calling() is properly checked."""
        # OpenAI should support function calling
        openai_llm = LLM(model="gpt-5-nano")
        assert hasattr(openai_llm, "supports_function_calling")
        assert openai_llm.supports_function_calling() is True

    def test_anthropic_supports_function_calling(self) -> None:
        """Test that Anthropic models support function calling."""
        with patch.dict(os.environ, {"ANTHROPIC_API_KEY": "test-key"}):
            llm = LLM(model="anthropic/claude-3-5-haiku-20241022")
            assert hasattr(llm, "supports_function_calling")
            assert llm.supports_function_calling() is True

    def test_gemini_supports_function_calling(self) -> None:
        """Test that Gemini models support function calling."""
        llm = LLM(model="gemini/gemini-2.5-flash")
        assert hasattr(llm, "supports_function_calling")
        assert llm.supports_function_calling() is True


# =============================================================================
# Token Usage Tests
# =============================================================================


class TestNativeToolCallingTokenUsage:
    """Tests for token usage with native tool calling."""

    @pytest.mark.vcr()
    def test_openai_native_tool_calling_token_usage(
        self, calculator_tool: CalculatorTool
    ) -> None:
        """Test token usage tracking with OpenAI native tool calling."""
        agent = Agent(
            role="Calculator",
            goal="Perform calculations efficiently",
            backstory="You calculate things.",
            tools=[calculator_tool],
            llm=LLM(model="gpt-5-nano"),
            verbose=False,
            max_iter=3,
        )

        task = Task(
            description="What is 100 / 4?",
            expected_output="The result",
            agent=agent,
        )

        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()

        assert result is not None
        assert result.token_usage is not None
        assert result.token_usage.total_tokens > 0
        assert result.token_usage.successful_requests >= 1

        print(f"\n[OPENAI NATIVE TOOL CALLING TOKEN USAGE]")
        print(f"  Prompt tokens: {result.token_usage.prompt_tokens}")
        print(f"  Completion tokens: {result.token_usage.completion_tokens}")
        print(f"  Total tokens: {result.token_usage.total_tokens}")

@pytest.mark.vcr()
def test_native_tool_calling_error_handling(failing_tool: FailingTool):
    """Test that native tool calling handles errors properly and emits error events."""
    import threading
    from crewai.events import crewai_event_bus
    from crewai.events.types.tool_usage_events import ToolUsageErrorEvent

    received_events = []
    event_received = threading.Event()

    @crewai_event_bus.on(ToolUsageErrorEvent)
    def handle_tool_error(source, event):
        received_events.append(event)
        event_received.set()

    agent = Agent(
        role="Calculator",
        goal="Perform calculations efficiently",
        backstory="You calculate things.",
        tools=[failing_tool],
        llm=LLM(model="gpt-5-nano"),
        verbose=False,
        max_iter=3,
    )

    result = agent.kickoff("Use the failing_tool to do something.")
    assert result is not None

    # Verify error event was emitted
    assert event_received.wait(timeout=10), "ToolUsageErrorEvent was not emitted"
    assert len(received_events) >= 1

    # Verify event attributes
    error_event = received_events[0]
    assert error_event.tool_name == "failing_tool"
    assert error_event.agent_role == agent.role
    assert "This tool always fails" in str(error_event.error)


# =============================================================================
# Max Usage Count Tests for Native Tool Calling
# =============================================================================


class CountingInput(BaseModel):
    """Input schema for counting tool."""

    value: str = Field(description="Value to count")


class CountingTool(BaseTool):
    """A tool that counts its usage."""

    name: str = "counting_tool"
    description: str = "A tool that counts how many times it's been called"
    args_schema: type[BaseModel] = CountingInput

    def _run(self, value: str) -> str:
        """Return the value with a count prefix."""
        return f"Counted: {value}"


class TestMaxUsageCountWithNativeToolCalling:
    """Tests for max_usage_count with native tool calling."""

    @pytest.mark.vcr()
    def test_max_usage_count_tracked_in_native_tool_calling(self) -> None:
        """Test that max_usage_count is properly tracked when using native tool calling."""
        tool = CountingTool(max_usage_count=3)

        # Verify initial state
        assert tool.max_usage_count == 3
        assert tool.current_usage_count == 0

        agent = Agent(
            role="Counting Agent",
            goal="Call the counting tool multiple times",
            backstory="You are an agent that counts things.",
            tools=[tool],
            llm=LLM(model="gpt-5-nano"),
            verbose=False,
            max_iter=5,
        )

        task = Task(
            description="Call the counting_tool 3 times with values 'first', 'second', and 'third'",
            expected_output="The results of the counting operations",
            agent=agent,
        )

        crew = Crew(agents=[agent], tasks=[task])
        crew.kickoff()

        # Verify usage count was tracked
        assert tool.max_usage_count == 3
        assert tool.current_usage_count <= tool.max_usage_count

    @pytest.mark.vcr()
    def test_max_usage_count_limit_enforced_in_native_tool_calling(self) -> None:
        """Test that when max_usage_count is reached, tool returns error message."""
        tool = CountingTool(max_usage_count=2)

        agent = Agent(
            role="Counting Agent",
            goal="Use the counting tool as many times as requested",
            backstory="You are an agent that counts things. You must try to use the tool for each value requested.",
            tools=[tool],
            llm=LLM(model="gpt-5-nano"),
            verbose=False,
            max_iter=5,
        )

        # Request more tool calls than the max_usage_count allows
        task = Task(
            description="Call the counting_tool 4 times with values 'one', 'two', 'three', and 'four'",
            expected_output="The results of the counting operations, noting any failures",
            agent=agent,
        )

        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()

        # The tool should have been limited to max_usage_count (2) calls
        assert result is not None
        assert tool.current_usage_count == tool.max_usage_count
        # After hitting the limit, further calls should have been rejected

    @pytest.mark.vcr()
    def test_tool_usage_increments_after_successful_execution(self) -> None:
        """Test that usage count increments after each successful native tool call."""
        tool = CountingTool(max_usage_count=10)

        assert tool.current_usage_count == 0

        agent = Agent(
            role="Counting Agent",
            goal="Use the counting tool exactly as requested",
            backstory="You are an agent that counts things precisely.",
            tools=[tool],
            llm=LLM(model="gpt-5-nano"),
            verbose=False,
            max_iter=5,
        )

        task = Task(
            description="Call the counting_tool exactly 2 times: first with value 'alpha', then with value 'beta'",
            expected_output="The results showing both 'Counted: alpha' and 'Counted: beta'",
            agent=agent,
        )

        crew = Crew(agents=[agent], tasks=[task])
        result = crew.kickoff()

        assert result is not None
        # Verify the requested calls occurred while keeping usage bounded.
        assert tool.current_usage_count >= 2
        assert tool.current_usage_count <= tool.max_usage_count


# =============================================================================
# JSON Parse Error Handling Tests
# =============================================================================


class TestNativeToolCallingJsonParseError:
    """Tests that malformed JSON tool arguments produce clear errors
    instead of silently dropping all arguments."""

    def _make_executor(self, tools: list[BaseTool]) -> "CrewAgentExecutor":
        """Create a minimal CrewAgentExecutor with mocked dependencies."""
        from crewai.agents.crew_agent_executor import CrewAgentExecutor
        from crewai.tools.base_tool import to_langchain

        structured_tools = to_langchain(tools)
        mock_agent = Mock()
        mock_agent.key = "test_agent"
        mock_agent.role = "tester"
        mock_agent.verbose = False
        mock_agent.fingerprint = None
        mock_agent.tools_results = []

        mock_task = Mock()
        mock_task.name = "test"
        mock_task.description = "test"
        mock_task.id = "test-id"

        executor = object.__new__(CrewAgentExecutor)
        executor.agent = mock_agent
        executor.task = mock_task
        executor.crew = Mock()
        executor.tools = structured_tools
        executor.original_tools = tools
        executor.tools_handler = None
        executor._printer = Mock()
        executor.messages = []

        return executor

    def test_malformed_json_returns_parse_error(self) -> None:
        """Malformed JSON args must return a descriptive error, not silently become {}."""

        class CodeTool(BaseTool):
            name: str = "execute_code"
            description: str = "Run code"

            def _run(self, code: str) -> str:
                return f"ran: {code}"

        tool = CodeTool()
        executor = self._make_executor([tool])

        from crewai.utilities.agent_utils import convert_tools_to_openai_schema
        _, available_functions, _ = convert_tools_to_openai_schema([tool])

        malformed_json = '{"code": "print("hello")"}'

        result = executor._execute_single_native_tool_call(
            call_id="call_123",
            func_name="execute_code",
            func_args=malformed_json,
            available_functions=available_functions,
        )

        assert "Failed to parse tool arguments as JSON" in result["result"]
        assert tool.current_usage_count == 0

    def test_valid_json_still_executes_normally(self) -> None:
        """Valid JSON args should execute the tool as before."""

        class CodeTool(BaseTool):
            name: str = "execute_code"
            description: str = "Run code"

            def _run(self, code: str) -> str:
                return f"ran: {code}"

        tool = CodeTool()
        executor = self._make_executor([tool])

        from crewai.utilities.agent_utils import convert_tools_to_openai_schema
        _, available_functions, _ = convert_tools_to_openai_schema([tool])

        valid_json = '{"code": "print(1)"}'

        result = executor._execute_single_native_tool_call(
            call_id="call_456",
            func_name="execute_code",
            func_args=valid_json,
            available_functions=available_functions,
        )

        assert result["result"] == "ran: print(1)"

    def test_dict_args_bypass_json_parsing(self) -> None:
        """When func_args is already a dict, no JSON parsing occurs."""

        class CodeTool(BaseTool):
            name: str = "execute_code"
            description: str = "Run code"

            def _run(self, code: str) -> str:
                return f"ran: {code}"

        tool = CodeTool()
        executor = self._make_executor([tool])

        from crewai.utilities.agent_utils import convert_tools_to_openai_schema
        _, available_functions, _ = convert_tools_to_openai_schema([tool])

        result = executor._execute_single_native_tool_call(
            call_id="call_789",
            func_name="execute_code",
            func_args={"code": "x = 42"},
            available_functions=available_functions,
        )

        assert result["result"] == "ran: x = 42"

    def test_schema_validation_catches_missing_args_on_native_path(self) -> None:
        """The native function calling path should now enforce args_schema,
        catching missing required fields before _run is called."""

        class StrictTool(BaseTool):
            name: str = "strict_tool"
            description: str = "A tool with required args"

            def _run(self, code: str, language: str) -> str:
                return f"{language}: {code}"

        tool = StrictTool()
        executor = self._make_executor([tool])

        from crewai.utilities.agent_utils import convert_tools_to_openai_schema
        _, available_functions, _ = convert_tools_to_openai_schema([tool])

        result = executor._execute_single_native_tool_call(
            call_id="call_schema",
            func_name="strict_tool",
            func_args={"code": "print(1)"},
            available_functions=available_functions,
        )

        assert "Error" in result["result"]
        assert "validation failed" in result["result"].lower() or "missing" in result["result"].lower()