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

using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

namespace Microsoft.DotNet.Build.Tasks.VisualStudio;

internal struct IbcEntry
{
    private const string TechnologyName = "IBC";
    private const string VSInstallationRootVar = "%VisualStudio.InstallationUnderTest.Path%";
    private const string DefaultNgenApplication = VSInstallationRootVar + "\\Common7\\IDE\\vsn.exe";

    public readonly string EntryName;
    public readonly string RelativeInstallationPath;
    public readonly string InstrumentationArguments;
    public readonly string RelativeDirectoryPath;

    public IbcEntry(string entryName, string relativeInstallationPath, string relativeDirectoryPath, string ngenApplicationPath)
    {
        string commandLineArg(string name, string value) => $"/{name}:\"{value}\"";

        EntryName = entryName;
        RelativeInstallationPath = relativeInstallationPath;
        RelativeDirectoryPath = relativeDirectoryPath;
        InstrumentationArguments = commandLineArg("ExeConfig", ngenApplicationPath);
    }

    public JObject ToJson()
        => new JObject(
            new JProperty("Technology", TechnologyName),
            new JProperty("RelativeInstallationPath", RelativeInstallationPath),
            new JProperty("InstrumentationArguments", InstrumentationArguments));


    public static IEnumerable<IbcEntry> GetEntriesFromAssembly(AssemblyOptProfTraining assembly)
    {
        foreach (var args in assembly.InstrumentationArguments)
        {
            yield return new IbcEntry(
                assembly.Assembly,
                relativeInstallationPath: args.RelativeInstallationFolder.Replace("/", "\\") + $"\\{assembly.Assembly}",
                relativeDirectoryPath: "",
                ngenApplicationPath: Path.Combine(VSInstallationRootVar, args.InstrumentationExecutable.Replace("/", "\\")));
        }
    }

    public static IEnumerable<IbcEntry> GetEntriesFromVsixJsonManifest(JObject json)
    {
        bool isNgened(JToken file)
            => file["ngen"] != null || file["ngenPriority"] != null || file["ngenArchitecture"] != null || file["ngenApplication"] != null;

        bool isPEFile(string filePath)
        {
            string ext = Path.GetExtension(filePath);
            return StringComparer.OrdinalIgnoreCase.Equals(ext, ".dll") ||
                   StringComparer.OrdinalIgnoreCase.Equals(ext, ".exe");
        }

        bool isSatelliteAssembly(string filePath)
            => Path.GetFileNameWithoutExtension(filePath).EndsWith(".resources");

        bool includeInIbcTraining(JToken file, string fileName)
            => isNgened(file) && isPEFile(fileName) && !isSatelliteAssembly(fileName);

        string replacePrefix(string path, string prefix, string replacement)
            => path.StartsWith(prefix, StringComparison.OrdinalIgnoreCase) ? replacement + path.Substring(prefix.Length) : path;

        if (json["extensionDir"] != null)
        {
            var extensionDir = replacePrefix((string)json["extensionDir"], "[installdir]\\", "");
            return from file in (JArray)json["files"]
                   let fileName = (string)file["fileName"]
                   where includeInIbcTraining(file, fileName)
                   let filePath = $"{extensionDir}\\{fileName.TrimStart('/').Replace("/", "\\")}"
                   select new IbcEntry(fileName, filePath, relativeDirectoryPath: Path.GetDirectoryName(fileName), DefaultNgenApplication);
        }
        else
        {
            return from file in (JArray)json["files"]
                   let fileName = (string)file["fileName"]
                   let ngenApplication = (string)file["ngenApplication"]
                   where includeInIbcTraining(file, fileName)
                   let filePath = fileName.Replace("/Contents/", string.Empty).Replace("/", "\\")
                   select new IbcEntry(
                       fileName,
                       filePath,
                       relativeDirectoryPath: "",
                       (ngenApplication != null) ? replacePrefix(ngenApplication, "[installdir]", VSInstallationRootVar) : DefaultNgenApplication);
        }
    }
}