dotnet__skills/tests/dotnet-msbuild/build-perf-diagnostics/DataService.cs

using Microsoft.Extensions.Logging;

namespace Contoso.WebApi;

public class DataService
{
    private readonly ILogger<DataService> _logger;

    public DataService(ILogger<DataService> logger)
    {
        _logger = logger;
    }

    private readonly Dictionary<string, List<int>> _data = new();

    public void AddValues(string key, params int[] values)
    {
        if (!_data.ContainsKey(key))
            _data[key] = new List<int>();
        _data[key].AddRange(values);
    }

    public double GetAverage(string key)
    {
        if (!_data.TryGetValue(key, out var values) || values.Count == 0)
            return 0.0;
        return values.Average();
    }

    public IReadOnlyDictionary<string, int> GetCounts()
    {
        return _data.ToDictionary(kv => kv.Key, kv => kv.Value.Count);
    }

    public string GenerateReport()
    {
        _logger.LogInformation("Generating report for {Count} keys", _data.Count);
        var sb = new System.Text.StringBuilder();
        foreach (var (key, values) in _data)
        {
            sb.AppendLine($"{key}: count={values.Count}, avg={values.Average():F2}, min={values.Min()}, max={values.Max()}");
        }
        return sb.ToString();
    }
}