import json
import os
from datetime import date
from unittest.mock import MagicMock, patch

import pytest

from garmin.sync import GarminSync


@pytest.fixture
def mock_client():
    return MagicMock()

@pytest.fixture
def temp_storage(tmp_path):
    return str(tmp_path / "data")

def test_get_last_sync_date(mock_client, temp_storage):
    os.makedirs(temp_storage, exist_ok=True)
    sync = GarminSync(mock_client, storage_dir=temp_storage)

    # 1. No files
    assert sync.get_last_sync_date() is None

    # 2. Add files
    today = date(2025, 12, 12)
    with open(os.path.join(temp_storage, "activity_1.json"), "w") as f:
        json.dump({"activityId": 1, "startTimeLocal": "2025-12-10 10:00:00"}, f)
    
    with open(os.path.join(temp_storage, "activity_2.json"), "w") as f:
        json.dump({"activityId": 2, "startTimeLocal": "2025-12-12 10:00:00"}, f)
    
    # 3. Invalid Date
    with open(os.path.join(temp_storage, "activity_bad.json"), "w") as f:
        json.dump({"activityId": 3, "startTimeLocal": "invalid-date"}, f)
        
    assert sync.get_last_sync_date() == today

def test_sync_smart_no_local(mock_client, temp_storage):
    os.makedirs(temp_storage, exist_ok=True)
    sync = GarminSync(mock_client, storage_dir=temp_storage)
    
    with patch.object(sync, 'sync_activities', return_value=10) as mock_sync_act:
        count = sync.sync_smart()
        assert count == 10
        mock_sync_act.assert_called_with(days=365)

def test_sync_smart_incremental(mock_client, temp_storage):
    os.makedirs(temp_storage, exist_ok=True)
    sync = GarminSync(mock_client, storage_dir=temp_storage)
    
    # Latest is 2 days ago
    mock_today = date(2025, 1, 5)
    last_sync = date(2025, 1, 3)
    
    with open(os.path.join(temp_storage, "activity_1.json"), "w") as f:
        json.dump({"activityId": 1, "startTimeLocal": f"{last_sync} 10:00:00"}, f)
        
    with patch("garmin.sync.date") as mock_date_cls:
        mock_date_cls.today.return_value = mock_today
        # Need to allow date constructor usage inside sync.py if used
        # But Sync.py imports date, datetime separately.
        
        # When we patch 'garmin.sync.date', we replace the class 'date' imported in that module
        # So date.today() is mocked.
        # But side effect: date(2025,1,5) might fail if we mocked the constructor?
        # Usually today is a classmethod. 
        
        # Simpler: sync_smart calculates days = (today - latest_date).days
        # If today=5th, latest=3rd. diff = 2.
        
        with patch.object(sync, 'sync_activities', return_value=5) as mock_sync_act:
            sync.sync_smart()
            mock_sync_act.assert_called_with(days=2)