// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
#nullable disable
 
using System;
 
namespace Microsoft.CodeAnalysis.Internal.Log;
 
/// <summary>
/// An interaction class defines how much time is expected to reach a time point, the response 
/// time point being the most commonly used. The interaction classes correspond to human perception,
/// so, for example, all interactions in the Fast class are perceived as fast and roughly feel like 
/// they have the same performance. By defining these interaction classes, we can describe 
/// performance using adjectives that have a precise, consistent meaning.
/// </summary>
internal enum InteractionClass
{
    Undefined, // use when we don't have a specific goal for this operation
 
    // Name             Target (ms)     Upper Bound (ms)        UX / Feedback
    Instant,         // <=50            100                     No noticeable delay
    Fast,            // 50-100          200                     Minimally noticeable delay
    Typical,         // 100-300         500                     Slower, but still no feedback necessary
    Responsive,      // 300-500         1,000                   Slower yet, potentially show Wait cursor
    Captive,         // >500            10,000                  Long, show Progress Dialog w/Cancel
    Extended,        // >500            >10,000                 Long enough for the user to switch to something else
}
 
[AttributeUsage(AttributeTargets.Field, AllowMultiple = false, Inherited = false)]
internal sealed class PerfGoalAttribute(InteractionClass interactionClass) : Attribute
{
    public InteractionClass InteractionClass => interactionClass;
}