import pytest
from unittest.mock import patch, MagicMock
import pandas as pd
from connectors.slack_handler import SlackHandler

@pytest.fixture
def slack_handler():
    return SlackHandler()

@patch('connectors.slack_handler.WebClient')
def test_fetch_messages_success(mock_webclient, slack_handler):
    mock_client = MagicMock()
    mock_webclient.return_value = mock_client
    
    mock_client.conversations_history.return_value = {
        "ok": True,
        "messages": [
            {"user": "U123", "text": "Hello world", "ts": "12345.67"}
        ]
    }

    df = slack_handler.fetch_messages("fake-token", "C123")
    assert not df.empty
    assert len(df) == 1
    assert df.iloc[0]["Content"] == "Hello world"
    assert df.iloc[0]["Sender"] == "U123"

@patch('connectors.slack_handler.WebClient')
def test_fetch_messages_api_error(mock_webclient, slack_handler):
    mock_client = MagicMock()
    mock_webclient.return_value = mock_client
    
    from slack_sdk.errors import SlackApiError
    mock_client.conversations_history.side_effect = SlackApiError("Error", response={"error": "channel_not_found"})

    df = slack_handler.fetch_messages("fake-token", "invalid")
    assert df.empty

@patch('connectors.slack_handler.WebClient')
def test_fetch_messages_http_error(mock_webclient, slack_handler):
    mock_webclient.side_effect = Exception("Some connection error")

    df = slack_handler.fetch_messages("fake-token", "C123")
    assert df.empty