using Microsoft.Extensions.Logging;

namespace Novelly.Api.Tests;

/// <summary>Records every entry logged through it, so tests can assert on what a service logged.</summary>
public record CapturedLogEntry(LogLevel Level, string Message, Exception? Exception);

/// <summary>
/// A test double for <see cref="ILogger{TCategoryName}"/> that captures entries instead of
/// writing them anywhere, so tests can assert a service logged at the right level with the
/// right values without standing up a real sink.
/// </summary>
public class CapturingLogger<T> : ILogger<T>
{
    public List<CapturedLogEntry> Entries { get; } = [];

    public IDisposable? BeginScope<TState>(TState state) where TState : notnull => null;

    public bool IsEnabled(LogLevel logLevel) => true;

    public void Log<TState>(
        LogLevel logLevel, EventId eventId, TState state, Exception? exception, Func<TState, Exception?, string> formatter) =>
        Entries.Add(new CapturedLogEntry(logLevel, formatter(state, exception), exception));
}