using Flawless.Server.Models;
using Microsoft.Extensions.Logging.Abstractions;

namespace Flawless.Server.Services;

public class DatabaseLoggerProvider(IServiceProvider serviceProvider) : ILoggerProvider
{
    public ILogger CreateLogger(string categoryName)
    {
        // 过滤非业务错误日志            
        if (!categoryName.StartsWith("Flawless.Server")) return NullLogger.Instance;
        return new DatabaseLogger(serviceProvider.CreateScope());
    }

    public void Dispose() { }
}

public class DatabaseLogger(IServiceScope scope) : ILogger
{
    private readonly AppDbContext _dbContext = scope.ServiceProvider.GetService<AppDbContext>()!;

    public IDisposable? BeginScope<TState>(TState state) => scope;

    public bool IsEnabled(LogLevel logLevel) => true;

    public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception? exception,
        Func<TState, Exception?, string> formatter)
    {
        try
        {
            _dbContext.SystemLogs.Add(new SystemLog
            {
                LogLevel = logLevel,
                Message = formatter(state, exception),
                Exception = exception?.ToString(),
                Timestamp = DateTime.UtcNow,
                Source = eventId.Name
            });
        
            _dbContext.SaveChanges();
        }
        catch (Exception e)
        {
            Console.Error.WriteLine("Cannot save logfile into database: " + e);
        }
    }
}