"""
Test HandoffPattern - Multi-Agent Handoff Coordination Pattern

Tests handoff pattern with dynamic tier escalation and complexity evaluation.
Covers factory function, pattern class, HandoffAgent, signatures, and integration.

Written BEFORE implementation (TDD).

Test Coverage:
- Factory Function: 8 tests
- Pattern Class: 7 tests
- HandoffAgent: 10 tests
- Integration Tests: 10 tests
Total: 35+ tests
"""

import pytest

# ============================================================================
# TEST CLASS 1: Factory Function (8 tests)
# ============================================================================


class TestCreateHandoffPattern:
    """Test create_handoff_pattern factory function."""

    def test_zero_config_creation(self):
        """Test zero-config pattern creation."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern()

        assert pattern is not None
        assert pattern.tiers is not None
        assert len(pattern.tiers) == 3  # default num_tiers
        assert pattern.shared_memory is not None
        assert 1 in pattern.tiers
        assert 2 in pattern.tiers
        assert 3 in pattern.tiers

    def test_custom_num_tiers(self):
        """Test creating pattern with custom tier count."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=5)

        assert len(pattern.tiers) == 5
        assert 1 in pattern.tiers
        assert 2 in pattern.tiers
        assert 3 in pattern.tiers
        assert 4 in pattern.tiers
        assert 5 in pattern.tiers

    def test_basic_parameter_override(self):
        """Test overriding basic parameters (model, temperature)."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(model="gpt-4", temperature=0.7, num_tiers=2)

        # Verify all tiers use same config
        for tier_level, agent in pattern.tiers.items():
            assert agent.config.model == "gpt-4"
            assert agent.config.temperature == 0.7

    def test_tier_configs_different_per_tier(self):
        """Test tier_configs with different config per tier."""
        from kaizen.agents.coordination import create_handoff_pattern

        tier_configs = {
            1: {"model": "gpt-3.5-turbo", "temperature": 0.3},
            2: {"model": "gpt-4", "temperature": 0.5},
            3: {"model": "gpt-4-turbo", "temperature": 0.7},
        }

        pattern = create_handoff_pattern(tier_configs=tier_configs)

        # Each tier should have its config
        assert pattern.tiers[1].config.model == "gpt-3.5-turbo"
        assert pattern.tiers[1].config.temperature == 0.3
        assert pattern.tiers[2].config.model == "gpt-4"
        assert pattern.tiers[2].config.temperature == 0.5
        assert pattern.tiers[3].config.model == "gpt-4-turbo"
        assert pattern.tiers[3].config.temperature == 0.7

    def test_custom_agents_provided(self):
        """Test providing pre-built HandoffAgent instances."""
        from kaizen.agents.coordination import create_handoff_pattern
        from kaizen.agents.coordination.handoff_pattern import HandoffAgent
        from kaizen.core.base_agent import BaseAgentConfig
        from kaizen.memory import SharedMemoryPool

        shared_memory = SharedMemoryPool()
        config = BaseAgentConfig(llm_provider="mock", model="gpt-3.5-turbo")

        custom_tier1 = HandoffAgent(
            config=config,
            shared_memory=shared_memory,
            tier_level=1,
            agent_id="custom_tier_1",
        )

        custom_tier2 = HandoffAgent(
            config=config,
            shared_memory=shared_memory,
            tier_level=2,
            agent_id="custom_tier_2",
        )

        tiers = {1: custom_tier1, 2: custom_tier2}
        pattern = create_handoff_pattern(tiers=tiers, shared_memory=shared_memory)

        # Should use provided agents
        assert pattern.tiers[1] is custom_tier1
        assert pattern.tiers[2] is custom_tier2
        assert len(pattern.tiers) == 2

    def test_environment_variable_fallback(self):
        """Test environment variable fallback for provider/model."""
        import os

        from kaizen.agents.coordination import create_handoff_pattern

        # Set env vars
        os.environ["KAIZEN_LLM_PROVIDER"] = "anthropic"
        os.environ["KAIZEN_MODEL"] = "claude-3-opus"

        try:
            pattern = create_handoff_pattern(num_tiers=1)

            # Should use env vars
            assert pattern.tiers[1].config.llm_provider == "anthropic"
            assert pattern.tiers[1].config.model == "claude-3-opus"
        finally:
            # Clean up
            os.environ.pop("KAIZEN_LLM_PROVIDER", None)
            os.environ.pop("KAIZEN_MODEL", None)

    def test_invalid_configuration_empty_tiers(self):
        """Test invalid configuration with empty tiers."""
        from kaizen.agents.coordination import create_handoff_pattern

        # Creating with 0 tiers should raise error
        with pytest.raises((ValueError, AssertionError)):
            create_handoff_pattern(num_tiers=0)

    def test_mixed_configuration_override(self):
        """Test mixed configuration (basic params + tier configs)."""
        from kaizen.agents.coordination import create_handoff_pattern

        # Base config for all tiers
        pattern = create_handoff_pattern(
            model="gpt-4",
            temperature=0.5,
            tier_configs={2: {"temperature": 0.9}},  # Override only tier 2 temperature
            num_tiers=3,
        )

        # Tier 1 should use base config
        assert pattern.tiers[1].config.model == "gpt-4"
        assert pattern.tiers[1].config.temperature == 0.5

        # Tier 2 should override temperature
        assert pattern.tiers[2].config.model == "gpt-4"
        assert pattern.tiers[2].config.temperature == 0.9

        # Tier 3 should use base config
        assert pattern.tiers[3].config.model == "gpt-4"
        assert pattern.tiers[3].config.temperature == 0.5


# ============================================================================
# TEST CLASS 2: Pattern Class (7 tests)
# ============================================================================


class TestHandoffPattern:
    """Test HandoffPattern class."""

    def test_add_tier_method(self):
        """Test add_tier method adds new tier."""
        from kaizen.agents.coordination import create_handoff_pattern
        from kaizen.agents.coordination.handoff_pattern import HandoffAgent
        from kaizen.core.base_agent import BaseAgentConfig

        pattern = create_handoff_pattern(num_tiers=2)

        # Add tier 3
        config = BaseAgentConfig(llm_provider="mock", model="gpt-3.5-turbo")
        tier3_agent = HandoffAgent(
            config=config,
            shared_memory=pattern.shared_memory,
            tier_level=3,
            agent_id="tier_3_agent",
        )

        pattern.add_tier(tier3_agent, tier_level=3)

        assert 3 in pattern.tiers
        assert pattern.tiers[3] is tier3_agent

    def test_execute_with_handoff_basic(self):
        """Test execute_with_handoff basic execution."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)

        result = pattern.execute_with_handoff(
            task="Simple task", context="", max_tier=3
        )

        assert isinstance(result, dict)
        assert "final_tier" in result
        assert "result" in result
        assert "execution_id" in result
        assert "escalation_count" in result

    def test_get_handoff_history(self):
        """Test get_handoff_history retrieves decisions."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)

        result = pattern.execute_with_handoff(
            task="Complex task requiring escalation", max_tier=3
        )

        execution_id = result["execution_id"]
        history = pattern.get_handoff_history(execution_id)

        assert isinstance(history, list)
        # Should have at least one handoff decision
        assert len(history) >= 1

    def test_validate_pattern_valid(self):
        """Test validate_pattern on valid pattern."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)

        assert pattern.validate_pattern() is True

    def test_validate_pattern_invalid_empty_tiers(self):
        """Test validate_pattern detects empty tiers."""
        from kaizen.agents.coordination.handoff_pattern import HandoffPattern
        from kaizen.memory import SharedMemoryPool

        pattern = HandoffPattern(tiers={}, shared_memory=SharedMemoryPool())

        assert pattern.validate_pattern() is False

    def test_tier_ordering_enforced(self):
        """Test tier levels are ordered correctly."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=5)

        tier_levels = list(pattern.tiers.keys())
        tier_levels.sort()

        assert tier_levels == [1, 2, 3, 4, 5]

    def test_max_tier_enforcement(self):
        """Test max_tier parameter enforces limit."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=5)

        # Execute with max_tier=2 (should not escalate beyond tier 2)
        result = pattern.execute_with_handoff(task="Very complex task", max_tier=2)

        # Final tier should be <= 2
        assert result["final_tier"] <= 2


# ============================================================================
# TEST CLASS 3: HandoffAgent (10 tests)
# ============================================================================


class TestHandoffAgent:
    """Test HandoffAgent class."""

    def test_agent_initialization(self):
        """Test HandoffAgent initialization."""
        from kaizen.agents.coordination.handoff_pattern import HandoffAgent
        from kaizen.core.base_agent import BaseAgentConfig
        from kaizen.memory import SharedMemoryPool

        shared_memory = SharedMemoryPool()
        config = BaseAgentConfig(llm_provider="mock", model="gpt-3.5-turbo")

        agent = HandoffAgent(
            config=config,
            shared_memory=shared_memory,
            tier_level=1,
            agent_id="test_tier_1",
        )

        assert agent.tier_level == 1
        assert agent.agent_id == "test_tier_1"
        assert agent.shared_memory is shared_memory

    def test_evaluate_task_method(self):
        """Test evaluate_task method."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)
        agent = pattern.tiers[1]

        evaluation = agent.evaluate_task(task="Simple task", context="")

        assert isinstance(evaluation, dict)
        assert "can_handle" in evaluation
        assert "complexity_score" in evaluation
        assert "reasoning" in evaluation
        assert "requires_tier" in evaluation

    def test_evaluate_task_can_handle_yes(self):
        """Test evaluate_task returns can_handle='yes' for simple tasks."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3, llm_provider="mock")
        agent = pattern.tiers[1]

        evaluation = agent.evaluate_task(task="Simple addition: 2+2", context="")

        # Tier 1 should handle simple tasks
        # Note: actual behavior depends on mock, but structure should be correct
        assert evaluation["can_handle"] in ["yes", "no"]
        assert isinstance(evaluation["complexity_score"], (int, float))
        assert 0.0 <= evaluation["complexity_score"] <= 1.0

    def test_evaluate_task_can_handle_no(self):
        """Test evaluate_task returns can_handle='no' for complex tasks."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3, llm_provider="mock")
        agent = pattern.tiers[1]

        evaluation = agent.evaluate_task(
            task="Solve complex quantum mechanics problem with relativistic corrections",
            context="Requires advanced physics knowledge",
        )

        # Structure should be correct regardless of actual decision
        assert evaluation["can_handle"] in ["yes", "no"]
        assert isinstance(evaluation["complexity_score"], (int, float))
        assert 0.0 <= evaluation["complexity_score"] <= 1.0

    def test_execute_task_method(self):
        """Test execute_task method."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)
        agent = pattern.tiers[1]

        result = agent.execute_task(task="Calculate 2+2", context="")

        assert isinstance(result, dict)
        assert "result" in result
        assert "confidence" in result
        assert "execution_metadata" in result

    def test_handoff_decision_logic(self):
        """Test handoff decision writes to shared memory."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)
        agent = pattern.tiers[1]

        # Evaluate task
        evaluation = agent.evaluate_task(task="Complex task", context="")

        # Should have written evaluation to shared memory
        insights = pattern.shared_memory.read_relevant(
            agent_id=agent.agent_id, tags=["handoff"], exclude_own=False
        )

        # Should have at least one handoff decision
        assert len(insights) >= 1

    def test_complexity_scoring(self):
        """Test complexity_score is within 0.0-1.0 range."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)
        agent = pattern.tiers[1]

        evaluation = agent.evaluate_task(task="Some task", context="")

        complexity = evaluation["complexity_score"]
        assert isinstance(complexity, (int, float))
        assert 0.0 <= complexity <= 1.0

    def test_shared_memory_writing(self):
        """Test agent writes handoff decision to shared memory."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)
        agent = pattern.tiers[2]

        # Clear shared memory first
        pattern.clear_shared_memory()

        # Evaluate task
        agent.evaluate_task(task="Test task", context="Test context")

        # Check shared memory
        insights = pattern.shared_memory.read_all()
        assert len(insights) >= 1

        # Should have handoff tag
        handoff_insights = [i for i in insights if "handoff" in i.get("tags", [])]
        assert len(handoff_insights) >= 1

    def test_tier_level_tracking(self):
        """Test tier_level is tracked in handoff decisions."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)
        agent = pattern.tiers[2]

        pattern.clear_shared_memory()

        agent.evaluate_task(task="Test task", context="")

        insights = pattern.shared_memory.read_all()
        handoff_insights = [i for i in insights if "handoff" in i.get("tags", [])]

        if handoff_insights:
            # Check metadata has tier_level
            insight = handoff_insights[0]
            metadata = insight.get("metadata", {})
            assert "tier_level" in metadata or "tier" in str(insight.get("tags", []))

    def test_custom_agent_logic(self):
        """Test agent can be customized with different tier levels."""
        from kaizen.agents.coordination.handoff_pattern import HandoffAgent
        from kaizen.core.base_agent import BaseAgentConfig
        from kaizen.memory import SharedMemoryPool

        shared_memory = SharedMemoryPool()

        # Create agents at different tiers
        config = BaseAgentConfig(llm_provider="mock", model="gpt-3.5-turbo")

        agent_tier1 = HandoffAgent(
            config=config, shared_memory=shared_memory, tier_level=1, agent_id="tier_1"
        )

        agent_tier3 = HandoffAgent(
            config=config, shared_memory=shared_memory, tier_level=3, agent_id="tier_3"
        )

        assert agent_tier1.tier_level == 1
        assert agent_tier3.tier_level == 3


# ============================================================================
# TEST CLASS 4: Integration Tests (10 tests)
# ============================================================================


class TestHandoffIntegration:
    """Test complete handoff workflow integration."""

    def test_three_tier_escalation(self):
        """Test escalation through tier1 -> tier2 -> tier3."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)

        # Execute complex task (should escalate)
        result = pattern.execute_with_handoff(
            task="Extremely complex multi-step problem requiring expert knowledge",
            context="High complexity",
            max_tier=3,
        )

        assert isinstance(result, dict)
        assert "final_tier" in result
        assert "escalation_count" in result
        # Should have escalated at least once or handled at tier 1
        assert result["final_tier"] >= 1

    def test_early_resolution_tier1(self):
        """Test tier1 handles simple task without escalation."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)

        result = pattern.execute_with_handoff(
            task="Simple task: 2+2", context="", max_tier=3
        )

        # Tier 1 might handle it (depends on mock)
        # But structure should be correct
        assert result["final_tier"] in [1, 2, 3]
        assert result["escalation_count"] >= 0

    def test_mid_tier_resolution(self):
        """Test tier1 -> tier2 (tier2 handles)."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)

        result = pattern.execute_with_handoff(
            task="Moderate complexity task", context="", max_tier=3
        )

        # Should resolve at some tier
        assert result["final_tier"] in [1, 2, 3]
        assert isinstance(result["result"], str)

    def test_max_tier_enforcement(self):
        """Test max_tier prevents escalation beyond limit."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=5)

        result = pattern.execute_with_handoff(
            task="Very complex task", max_tier=2  # Limit to tier 2
        )

        # Should not exceed tier 2
        assert result["final_tier"] <= 2

    def test_context_preservation(self):
        """Test context is preserved through escalation."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)

        context = "Important context information"
        result = pattern.execute_with_handoff(
            task="Task requiring context", context=context, max_tier=3
        )

        # Should have executed successfully
        assert isinstance(result, dict)
        assert "result" in result

    def test_handoff_history_retrieval(self):
        """Test complete handoff history is retrievable."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)

        result = pattern.execute_with_handoff(
            task="Task for history tracking", max_tier=3
        )

        execution_id = result["execution_id"]
        history = pattern.get_handoff_history(execution_id)

        assert isinstance(history, list)
        assert len(history) >= 1

        # Each history entry should have expected fields
        for decision in history:
            assert "tier_level" in decision or "tier_level" in decision.get(
                "metadata", {}
            )

    def test_empty_tiers_error(self):
        """Test pattern with no tiers raises error."""
        from kaizen.agents.coordination.handoff_pattern import HandoffPattern
        from kaizen.memory import SharedMemoryPool

        pattern = HandoffPattern(tiers={}, shared_memory=SharedMemoryPool())

        # Should fail validation
        assert pattern.validate_pattern() is False

        # Execution should handle gracefully or raise error
        with pytest.raises((ValueError, KeyError, AssertionError)):
            pattern.execute_with_handoff("task", max_tier=3)

    def test_single_tier_handoff(self):
        """Test handoff with only one tier."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=1)

        result = pattern.execute_with_handoff(task="Task with single tier", max_tier=1)

        # Should execute at tier 1
        assert result["final_tier"] == 1
        assert result["escalation_count"] == 0

    def test_complex_escalation_scenario(self):
        """Test complex escalation with multiple tiers."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=5)

        result = pattern.execute_with_handoff(
            task="Complex escalation scenario",
            context="Multiple tier evaluation",
            max_tier=5,
        )

        assert result["final_tier"] >= 1
        assert result["final_tier"] <= 5
        assert isinstance(result["execution_id"], str)

    def test_confidence_scoring(self):
        """Test confidence scoring in task execution."""
        from kaizen.agents.coordination import create_handoff_pattern

        pattern = create_handoff_pattern(num_tiers=3)

        result = pattern.execute_with_handoff(
            task="Task for confidence scoring", max_tier=3
        )

        # Result should have confidence if execution happened
        assert isinstance(result, dict)
        # Confidence might be in nested result
        if "confidence" in result:
            assert 0.0 <= result["confidence"] <= 1.0
