// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using Microsoft.CodeAnalysis.Diagnostics;
using System;
using System.Linq;

namespace Microsoft.DotNet.CodeAnalysis.Analyzers;

public abstract class BaseAnalyzer : DiagnosticAnalyzer
{
    private const string ConfigFileName = @"disabledAnalyzers.config";

    public sealed override void Initialize(AnalysisContext context)
    {
        context.EnableConcurrentExecution();
        context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.Analyze | GeneratedCodeAnalysisFlags.ReportDiagnostics);
        context.RegisterCompilationStartAction(InitializeAnalyzer);
    }

    private void InitializeAnalyzer(CompilationStartAnalysisContext context)
    {
        var configFile = context.Options.AdditionalFiles.FirstOrDefault(file => file.Path.Contains(ConfigFileName));

        if (configFile != null)
        {
            foreach (var line in configFile.GetText().Lines)
            {
                if (StringComparer.OrdinalIgnoreCase.Equals(line.ToString(), GetType().Name))
                {
                    return;
                }
            }
        }

        OnCompilationStart(context);
    }

    /// <summary>
    /// This is going to be called only if the analyzer was not disabled
    /// </summary>
    /// <param name="context"></param>
    public abstract void OnCompilationStart(CompilationStartAnalysisContext context);
}