import pytest
from unittest.mock import AsyncMock, MagicMock, patch
from aiogram.types import Message, BufferedInputFile
from aiogram.filters import CommandObject
from datetime import datetime

from src.bot.handlers import get_router
from src.processor.dto import EnrichedNewsItemDTO

@pytest.fixture
def mock_storage():
    return AsyncMock()

@pytest.fixture
def mock_processor():
    processor = MagicMock()
    processor.get_info.return_value = {"model": "test-model"}
    return processor

@pytest.fixture
def allowed_chat_id():
    return "123456789"

@pytest.fixture
def router(mock_storage, mock_processor, allowed_chat_id):
    return get_router(mock_storage, mock_processor, allowed_chat_id)

def get_handler(router, callback_name):
    for handler in router.message.handlers:
        if handler.callback.__name__ == callback_name:
            return handler.callback
    raise ValueError(f"Handler {callback_name} not found")

@pytest.fixture
def mock_items():
    return [
        EnrichedNewsItemDTO(
            title=f"Hot News {i}",
            url=f"https://example.com/{i}",
            content_text=f"Content {i}",
            source="Source",
            timestamp=datetime.now(),
            relevance_score=10-i,
            summary_ru=f"Сводка {i}",
            anomalies_detected=[],
            category="Tech"
        ) for i in range(3)
    ]

@pytest.mark.asyncio
async def test_command_get_hottest_handler_no_args(router, mock_storage, allowed_chat_id, mock_items):
    """
    Test /get_hottest with no arguments (default limit 10, format csv).
    """
    # 1. Arrange
    handler = get_handler(router, "command_get_hottest_handler")
    message = AsyncMock()
    message.chat = MagicMock()
    message.chat.id = int(allowed_chat_id)
    
    mock_storage.get_top_ranked.return_value = mock_items
    
    # 2. Act
    command = CommandObject(prefix='/', command='get_hottest', args=None)
    with patch("src.bot.handlers.CsvTrendExporter") as MockCsvExporter:
        mock_exporter = AsyncMock()
        mock_exporter.export.return_value = b"csv data"
        MockCsvExporter.return_value = mock_exporter
        
        await handler(message=message, command=command)
    
    # 3. Assert
    mock_storage.get_top_ranked.assert_called_once_with(limit=10)
    message.answer_document.assert_called_once()
    
    args, kwargs = message.answer_document.call_args
    assert "document" in kwargs
    assert isinstance(kwargs["document"], BufferedInputFile)
    assert kwargs["document"].filename == "hottest_trends.csv"
    assert kwargs["caption"] == "🔥 Top 3 hottest trends!"

@pytest.mark.asyncio
async def test_command_get_hottest_handler_invalid_limit(router, mock_storage, allowed_chat_id):
    """
    Test /get_hottest with invalid limit (not a number).
    """
    # 1. Arrange
    handler = get_handler(router, "command_get_hottest_handler")
    message = AsyncMock()
    message.chat = MagicMock()
    message.chat.id = int(allowed_chat_id)
    
    # 2. Act
    command = CommandObject(prefix='/', command='get_hottest', args='abc')
    await handler(message=message, command=command)
    
    # 3. Assert
    message.answer.assert_called_once_with("Please provide a valid number, e.g., /get_hottest 10")
    mock_storage.get_top_ranked.assert_not_called()

@pytest.mark.asyncio
async def test_command_get_hottest_handler_capped_limit(router, mock_storage, allowed_chat_id, mock_items):
    """
    Test /get_hottest with limit > 50 (should be capped).
    """
    # 1. Arrange
    handler = get_handler(router, "command_get_hottest_handler")
    message = AsyncMock()
    message.chat = MagicMock()
    message.chat.id = int(allowed_chat_id)
    
    mock_storage.get_top_ranked.return_value = mock_items
    
    # 2. Act
    command = CommandObject(prefix='/', command='get_hottest', args='100')
    await handler(message=message, command=command)
    
    # 3. Assert
    mock_storage.get_top_ranked.assert_called_once_with(limit=50)

@pytest.mark.asyncio
async def test_command_get_hottest_handler_custom_limit_md(router, mock_storage, allowed_chat_id, mock_items):
    """
    Test /get_hottest with limit and md format.
    """
    # 1. Arrange
    handler = get_handler(router, "command_get_hottest_handler")
    message = AsyncMock()
    message.chat = MagicMock()
    message.chat.id = int(allowed_chat_id)
    
    mock_storage.get_top_ranked.return_value = mock_items
    
    # 2. Act
    command = CommandObject(prefix='/', command='get_hottest', args='5 md')
    with patch("src.bot.handlers.MarkdownTrendExporter") as MockMdExporter:
        mock_exporter = AsyncMock()
        mock_exporter.export.return_value = b"md data"
        MockMdExporter.return_value = mock_exporter
        
        await handler(message=message, command=command)
    
    # 3. Assert
    mock_storage.get_top_ranked.assert_called_once_with(limit=5)
    message.answer_document.assert_called_once()
    
    args, kwargs = message.answer_document.call_args
    assert kwargs["document"].filename == "hottest_trends.md"
    assert kwargs["caption"] == "🔥 Top 3 hottest trends!"

@pytest.mark.asyncio
async def test_command_get_hottest_handler_no_records(router, mock_storage, allowed_chat_id):
    """
    Test /get_hottest when no records found.
    """
    # 1. Arrange
    handler = get_handler(router, "command_get_hottest_handler")
    message = AsyncMock()
    message.chat = MagicMock()
    message.chat.id = int(allowed_chat_id)
    
    mock_storage.get_top_ranked.return_value = []
    
    # 2. Act
    command = CommandObject(prefix='/', command='get_hottest', args=None)
    await handler(message=message, command=command)
    
    # 3. Assert
    message.answer.assert_called_once_with("No hot trends found yet.")
    message.answer_document.assert_not_called()