// 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.

using System;
using Microsoft.CodeAnalysis.Internal.Log;

namespace Microsoft.CodeAnalysis.Completion.Log;

internal static class CompletionProvidersLogger
{
    private static readonly StatisticLogAggregator<ActionInfo> s_statisticLogAggregator = new();
    private static readonly CountLogAggregator<ActionInfo> s_countLogAggregator = new();

    private static readonly HistogramLogAggregator<ActionInfo> s_histogramLogAggregator = new(bucketSize: 50, maxBucketValue: 1000);

    internal enum ActionInfo
    {
        TypeImportCompletionTicks,
        TypeImportCompletionItemCount,
        TypeImportCompletionReferenceCount,
        TypeImportCompletionCacheMissCount,
        CommitsOfTypeImportCompletionItem,

        ExtensionMethodCompletionTicks,
        ExtensionMethodCompletionMethodsProvided,
        ExtensionMethodCompletionGetSymbolsTicks,
        ExtensionMethodCompletionCreateItemsTicks,
        ExtensionMethodCompletionRemoteAssetSyncTicks,
        ExtensionMethodCompletionRemoteTicks,
        CommitsOfExtensionMethodImportCompletionItem,
        ExtensionMethodCompletionPartialResultCount,

        CommitUsingSemicolonToAddParenthesis,
        CommitUsingDotToAddParenthesis
    }

    internal static void LogTypeImportCompletionTicksDataPoint(TimeSpan elapsed)
    {
        s_histogramLogAggregator.LogTime(ActionInfo.TypeImportCompletionTicks, elapsed);
        s_statisticLogAggregator.AddDataPoint(ActionInfo.TypeImportCompletionTicks, elapsed);
    }

    internal static void LogTypeImportCompletionItemCountDataPoint(int count)
        => s_statisticLogAggregator.AddDataPoint(ActionInfo.TypeImportCompletionItemCount, count);

    internal static void LogTypeImportCompletionReferenceCountDataPoint(int count)
        => s_statisticLogAggregator.AddDataPoint(ActionInfo.TypeImportCompletionReferenceCount, count);

    internal static void LogTypeImportCompletionCacheMiss()
        => s_countLogAggregator.IncreaseCount(ActionInfo.TypeImportCompletionCacheMissCount);

    internal static void LogCommitOfTypeImportCompletionItem()
        => s_countLogAggregator.IncreaseCount(ActionInfo.CommitsOfTypeImportCompletionItem);

    internal static void LogExtensionMethodCompletionMethodsProvidedDataPoint(int count)
        => s_statisticLogAggregator.AddDataPoint(ActionInfo.ExtensionMethodCompletionMethodsProvided, count);

    internal static void LogCommitOfExtensionMethodImportCompletionItem()
        => s_countLogAggregator.IncreaseCount(ActionInfo.CommitsOfExtensionMethodImportCompletionItem);

    internal static void LogExtensionMethodCompletionPartialResultCount()
        => s_countLogAggregator.IncreaseCount(ActionInfo.ExtensionMethodCompletionPartialResultCount);

    internal static void LogCommitUsingSemicolonToAddParenthesis()
        => s_countLogAggregator.IncreaseCount(ActionInfo.CommitUsingSemicolonToAddParenthesis);

    internal static void LogCommitUsingDotToAddParenthesis()
        => s_countLogAggregator.IncreaseCount(ActionInfo.CommitUsingDotToAddParenthesis);

    internal static void LogCustomizedCommitToAddParenthesis(char? commitChar)
    {
        switch (commitChar)
        {
            case '.':
                LogCommitUsingDotToAddParenthesis();
                break;
            case ';':
                LogCommitUsingSemicolonToAddParenthesis();
                break;
        }
    }

    internal static void ReportTelemetry()
    {
        Logger.Log(FunctionId.Intellisense_CompletionProviders_Data, KeyValueLogMessage.Create(static m =>
        {
            foreach (var kv in s_statisticLogAggregator)
            {
                var statistics = kv.Value.GetStatisticResult();
                statistics.WriteTelemetryPropertiesTo(m, prefix: kv.Key.ToString());
            }

            foreach (var kv in s_countLogAggregator)
            {
                m[kv.Key.ToString()] = kv.Value.GetCount();
            }

            foreach (var kv in s_histogramLogAggregator)
            {
                kv.Value.WriteTelemetryPropertiesTo(m, prefix: kv.Key.ToString());
            }
        }));
    }
}