import pytest
from unittest.mock import patch, MagicMock
from io import BytesIO

# Import all functions to test
from utils import (
    extract_keywords,
    parse_resume,
    extract_email,
    score_candidate,
    summarize_resume,
    filter_resumes_by_keywords,
    evaluate_resumes,
    store_in_supabase,
    generate_pdf_report,
    generate_interview_questions_from_summaries
)

# Run Command for Full Coverage Report: pytest --cov=utils --cov-report=term-missing -v

# --- Mock Models and External APIs ---
@pytest.fixture(autouse=True)
def patch_embedding_model(monkeypatch):
    mock_model = MagicMock()
    mock_model.encode.return_value = [0.1, 0.2, 0.3]
    monkeypatch.setattr("utils.embedding_model", mock_model)


@pytest.fixture(autouse=True)
def patch_spacy(monkeypatch):
    nlp_mock = MagicMock()
    nlp_mock.return_value = [MagicMock(text="python", pos_="NOUN", is_stop=False)]
    monkeypatch.setattr("utils.nlp", nlp_mock)


# --- extract_keywords ---
def test_extract_keywords():
    text = "We are looking for a Python developer with Django and REST experience."
    keywords = extract_keywords(text)
    assert isinstance(keywords, list)
    assert "python" in keywords or len(keywords) > 0


# --- parse_resume ---
def test_parse_resume():
    dummy_pdf = MagicMock()
    dummy_pdf.read.return_value = b"%PDF-1.4"
    with patch("fitz.open") as mocked_fitz:
        page_mock = MagicMock()
        page_mock.get_text.return_value = "Resume Text Here"
        mocked_fitz.return_value = [page_mock]
        result = parse_resume(dummy_pdf)
        assert "Resume Text" in result


# --- extract_email ---
def test_extract_email():
    text = "Contact me at johndoe@example.com for more info."
    assert extract_email(text) == "johndoe@example.com"

    assert extract_email("No email here!") is None


# --- score_candidate ---
def test_score_candidate():
    score = score_candidate("Experienced Python developer", "Looking for Python engineer")
    assert isinstance(score, float)
    assert 0 <= score <= 1


# --- summarize_resume ---
@patch("utils.query")
def test_summarize_resume(mock_query):
    mock_query.return_value = [{"generated_text": "This is a summary"}]
    summary = summarize_resume("This is a long resume text.")
    assert summary == "This is a summary"

    mock_query.return_value = None
    fallback = summarize_resume("Another resume")
    assert "unavailable" in fallback.lower()


# --- filter_resumes_by_keywords ---
def test_filter_resumes_by_keywords():
    resumes = [
        {"name": "John", "resume": "python django rest api"},
        {"name": "Doe", "resume": "java spring"}
    ]
    job_description = "Looking for a python developer with API knowledge."
    filtered, removed = filter_resumes_by_keywords(resumes, job_description, min_keyword_match=1)

    assert isinstance(filtered, list)
    assert isinstance(removed, list)
    assert len(filtered) + len(removed) == 2


# --- evaluate_resumes ---
@patch("utils.parse_resume", return_value="python flask api")
@patch("utils.extract_email", return_value="test@example.com")
@patch("utils.summarize_resume", return_value="A senior Python developer.")
@patch("utils.score_candidate", return_value=0.85)
def test_evaluate_resumes(_, __, ___, ____):
    class DummyFile:
        def __init__(self, name): self.name = name
        def read(self): return b"%PDF-1.4"

    uploaded_files = [DummyFile("resume1.pdf")]
    job_desc = "Looking for a python developer."

    shortlisted, removed = evaluate_resumes(uploaded_files, job_desc)
    assert len(shortlisted) == 1
    assert isinstance(removed, list)


# --- store_in_supabase ---
@patch("utils.supabase")
def test_store_in_supabase(mock_supabase):
    table_mock = MagicMock()
    table_mock.insert.return_value.execute.return_value = {"status": "success"}
    mock_supabase.table.return_value = table_mock

    response = store_in_supabase("text", 0.8, "John", "john@example.com", "summary")
    assert "status" in response


# --- generate_pdf_report ---
def test_generate_pdf_report():
    candidates = [{
        "name": "John Doe",
        "email": "john@example.com",
        "score": 0.87,
        "summary": "Python developer"
    }]
    pdf = generate_pdf_report(candidates, questions=["What are your strengths?"])
    assert isinstance(pdf, BytesIO)


# --- generate_interview_questions_from_summaries ---
@patch("utils.client.chat_completion")
def test_generate_interview_questions_from_summaries(mock_chat):
    mock_chat.return_value.choices = [
        MagicMock(message=MagicMock(content="""
            1. What are your strengths?
            2. Describe a project you've led.
            3. How do you handle tight deadlines?
        """))
    ]

    candidates = [{"summary": "Experienced Python developer"}]
    questions = generate_interview_questions_from_summaries(candidates)
    assert len(questions) > 0
    assert all(q.startswith("Q") for q in questions)

@patch("utils.supabase")
def test_store_in_supabase(mock_supabase):
    mock_table = MagicMock()
    mock_execute = MagicMock()
    mock_execute.return_value = {"status": "success"}

    # Attach mocks
    mock_table.insert.return_value.execute = mock_execute
    mock_supabase.table.return_value = mock_table

    data = {
        "resume_text": "Some text",
        "score": 0.85,
        "candidate_name": "Alice",
        "email": "alice@example.com",
        "summary": "Experienced backend developer"
    }

    response = store_in_supabase(**data)
    assert response["status"] == "success"

    mock_supabase.table.assert_called_once_with("candidates")
    mock_table.insert.assert_called_once()
    inserted_data = mock_table.insert.call_args[0][0]
    assert inserted_data["name"] == "Alice"
    assert inserted_data["email"] == "alice@example.com"

def test_extract_keywords_empty_input():
    assert extract_keywords("") == []

def test_extract_email_malformed():
    malformed_text = "email at example dot com"
    assert extract_email(malformed_text) is None

def test_score_candidate_failure(monkeypatch):
    def broken_encode(*args, **kwargs): raise Exception("fail")
    monkeypatch.setattr("utils.embedding_model.encode", broken_encode)
    score = score_candidate("resume", "job description")
    assert score == 0

@patch("utils.query")
def test_summarize_resume_bad_response(mock_query):
    mock_query.return_value = {"weird_key": "no summary here"}
    summary = summarize_resume("Resume text")
    assert "unavailable" in summary.lower()

@patch("utils.query")
def test_summarize_resume_bad_response(mock_query):
    mock_query.return_value = {"weird_key": "no summary here"}
    summary = summarize_resume("Resume text")
    assert "unavailable" in summary.lower()

@patch("utils.parse_resume", return_value="some text")
@patch("utils.extract_email", return_value=None)
@patch("utils.summarize_resume", return_value="Summary here")
@patch("utils.score_candidate", return_value=0.1)
def test_evaluate_resumes_low_score_filtered(_, __, ___, ____):
    class Dummy:
        name = "resume.pdf"
        def read(self): return b"%PDF"

    uploaded = [Dummy()]
    shortlisted, removed = evaluate_resumes(uploaded, "job description")
    assert len(shortlisted) == 0
    assert len(removed) == 1