import json
from unittest.mock import patch

import pytest

from workflows.errors import CyclicDependencyError, WorkflowError
from workflows.executors import (
    create_processed_inputs,
    execute_model_step,
    execute_workflow,
    lower,
    upper,
)
from workflows.structs import InputField, ModelStep, OutputField, Workflow

# Tests for utility functions


def test_upper():
    """Test the upper function with different input types."""
    assert upper("hello") == "HELLO"
    assert upper("Hello World") == "HELLO WORLD"
    assert upper("") == ""
    # Non-string inputs should be returned unchanged
    assert upper(123) == 123
    assert upper([1, 2, 3]) == [1, 2, 3]
    assert upper(None) is None


def test_lower():
    """Test the lower function with different input types."""
    assert lower("HELLO") == "hello"
    assert lower("Hello World") == "hello world"
    assert lower("") == ""
    # Non-string inputs should be returned unchanged
    assert lower(123) == 123
    assert lower([1, 2, 3]) == [1, 2, 3]
    assert lower(None) is None


# Tests for create_processed_inputs


def test_create_processed_inputs_basic():
    """Test basic input processing without transformations."""
    step = ModelStep(
        id="test_step",
        model="gpt-4",
        provider="openai",
        call_type="llm",
        system_prompt="Test prompt",
        input_fields=[InputField(name="text", description="Input text", variable="input_text")],
        output_fields=[],
    )
    available_vars = {"input_text": "Hello World"}

    result = create_processed_inputs(step, available_vars)
    assert result == {"text": "Hello World"}


def test_create_processed_inputs_with_transformation():
    """Test input processing with transformation functions."""
    step = ModelStep(
        id="test_step",
        model="gpt-4",
        provider="openai",
        call_type="llm",
        system_prompt="Test prompt",
        input_fields=[
            InputField(name="upper_text", description="Uppercase text", variable="input_text", func="upper"),
            InputField(name="lower_text", description="Lowercase text", variable="input_caps", func="lower"),
        ],
        output_fields=[],
    )
    available_vars = {"input_text": "hello", "input_caps": "WORLD"}

    result = create_processed_inputs(step, available_vars)
    assert result == {"upper_text": "HELLO", "lower_text": "world"}


def test_create_processed_inputs_missing_var():
    """Test that appropriate error is raised when a variable is missing."""
    step = ModelStep(
        id="test_step",
        model="gpt-4",
        provider="openai",
        call_type="llm",
        system_prompt="Test prompt",
        input_fields=[InputField(name="text", description="Input text", variable="missing_var")],
        output_fields=[],
    )
    available_vars = {"input_text": "Hello World"}

    with pytest.raises(KeyError):
        create_processed_inputs(step, available_vars)


def test_create_processed_inputs_unknown_func():
    """Test that appropriate error is raised when an unknown function is specified."""
    step = ModelStep(
        id="test_step",
        model="gpt-4",
        provider="openai",
        call_type="llm",
        system_prompt="Test prompt",
        input_fields=[InputField(name="text", description="Input text", variable="input_text", func="unknown_func")],
        output_fields=[],
    )
    available_vars = {"input_text": "Hello World"}

    # This should raise an error when the function isn't found
    with pytest.raises(Exception):
        create_processed_inputs(step, available_vars)


# Tests for execute_model_step


@patch("workflows.executors.litellm.completion")
def test_execute_model_step_success(mock_completion):
    """Test successful execution of a model step with mocked litellm response."""
    # Mock the litellm response
    mock_response = {"choices": [{"message": {"content": json.dumps({"summary": "This is a summary"})}}]}
    mock_completion.return_value = mock_response

    # Create a test step
    step = ModelStep(
        id="summarize",
        model="gpt-3.5-turbo",
        provider="openai",
        call_type="llm",
        system_prompt="Summarize the text",
        input_fields=[InputField(name="text", description="Text to summarize", variable="input_text")],
        output_fields=[OutputField(name="summary", description="Summary of the text", type="str")],
    )

    # Execute the step
    result = execute_model_step(step, {"input_text": "Long text to be summarized..."})

    # Verify the results
    assert result == {"summary": "This is a summary"}

    # Verify the litellm call was made correctly
    mock_completion.assert_called_once()
    args, kwargs = mock_completion.call_args
    assert kwargs["model"] == "gpt-3.5-turbo"
    assert "Summarize the text" in kwargs["messages"][0]["content"]


@patch("workflows.executors.litellm.completion")
def test_execute_model_step_error(mock_completion):
    """Test handling of errors in model step execution."""
    # Make litellm raise an exception
    mock_completion.side_effect = Exception("API Error")

    # Create a test step
    step = ModelStep(
        id="summarize",
        model="gpt-3.5-turbo",
        provider="openai",
        call_type="llm",
        system_prompt="Summarize the text",
        input_fields=[InputField(name="text", description="Text to summarize", variable="input_text")],
        output_fields=[OutputField(name="summary", description="Summary of the text", type="str")],
    )

    # Execute the step - should raise an exception
    with pytest.raises(Exception):
        execute_model_step(step, {"input_text": "Long text to be summarized..."})


# Tests for execute_workflow


@patch("workflows.executors.execute_model_step")
def test_execute_workflow_simple(mock_execute_step):
    """Test execution of a simple workflow with a single step."""
    # Configure mock to return expected outputs
    mock_execute_step.return_value = {"summary": "This is a summary"}

    # Create a simple workflow
    step = ModelStep(
        id="summarize",
        model="gpt-3.5-turbo",
        provider="openai",
        call_type="llm",
        system_prompt="Summarize the text",
        input_fields=[InputField(name="text", description="Text to summarize", variable="input_text")],
        output_fields=[OutputField(name="summary", description="Summary of the text", type="str")],
    )

    workflow = Workflow(steps={"summarize": step}, inputs=["input_text"], outputs={"summary": "summarize.summary"})

    # Execute the workflow
    result = execute_workflow(workflow, {"input_text": "Long text to be summarized..."})

    # Verify the results
    assert result == {"summary": "This is a summary"}

    # Verify execute_model_step was called correctly
    mock_execute_step.assert_called_once()


@patch("workflows.executors.execute_model_step")
def test_execute_workflow_multi_step(mock_execute_step):
    """Test execution of a multi-step workflow with dependencies."""

    # Configure mock to return different values based on the step
    def side_effect(step, available_vars):
        if step.id == "extract":
            return {"entities": ["Apple", "product"]}
        elif step.id == "analyze":
            return {"sentiment": "positive"}
        return {}

    mock_execute_step.side_effect = side_effect

    # Create extract step
    extract_step = ModelStep(
        id="extract",
        model="gpt-3.5-turbo",
        provider="openai",
        call_type="llm",
        system_prompt="Extract entities",
        input_fields=[InputField(name="text", description="Text to analyze", variable="input_text")],
        output_fields=[OutputField(name="entities", description="Extracted entities", type="list[str]")],
    )

    # Create analyze step that depends on extract step
    analyze_step = ModelStep(
        id="analyze",
        model="gpt-4",
        provider="openai",
        call_type="llm",
        system_prompt="Analyze sentiment",
        input_fields=[InputField(name="entities", description="Entities to analyze", variable="extract.entities")],
        output_fields=[OutputField(name="sentiment", description="Sentiment analysis", type="str")],
    )

    workflow = Workflow(
        steps={"extract": extract_step, "analyze": analyze_step},
        inputs=["input_text"],
        outputs={"entities": "extract.entities", "sentiment": "analyze.sentiment"},
    )

    # Execute the workflow
    result = execute_workflow(workflow, {"input_text": "Apple is launching a new product tomorrow."})

    # Verify the results
    assert result == {"entities": ["Apple", "product"], "sentiment": "positive"}

    # Verify execute_model_step was called twice (once for each step)
    assert mock_execute_step.call_count == 2


def test_execute_workflow_missing_input():
    """Test that an error is raised when a required input is missing."""
    step = ModelStep(
        id="summarize",
        model="gpt-3.5-turbo",
        provider="openai",
        call_type="llm",
        system_prompt="Summarize the text",
        input_fields=[InputField(name="text", description="Text to summarize", variable="input_text")],
        output_fields=[OutputField(name="summary", description="Summary of the text", type="str")],
    )

    workflow = Workflow(steps={"summarize": step}, inputs=["input_text"], outputs={"summary": "summarize.summary"})

    # Execute with missing input
    with pytest.raises(WorkflowError, match="Missing required workflow input"):
        execute_workflow(workflow, {})


@patch("workflows.executors.create_dependency_graph")
def test_execute_workflow_cyclic_dependency(mock_dependency_graph):
    """Test that a cyclic dependency in the workflow raises an appropriate error."""
    # Make create_dependency_graph raise a CyclicDependencyError
    mock_dependency_graph.side_effect = CyclicDependencyError()

    step = ModelStep(
        id="test",
        model="gpt-3.5-turbo",
        provider="openai",
        call_type="llm",
        system_prompt="Test",
        input_fields=[],
        output_fields=[],
    )

    workflow = Workflow(steps={"test": step}, inputs=[], outputs=[])

    # This should propagate the CyclicDependencyError
    with pytest.raises(CyclicDependencyError):
        execute_workflow(workflow, {})