#nullable enable

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Xml.Linq;

namespace ShrinkSDK.Godot.Editor;

public static class ShrinkProjectPackageEditor
{
    public static readonly IReadOnlyDictionary<string, string> RecommendedPackages =
        new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
        {
            ["ShrinkSDK.Godot"] = "0.1.0",
            ["ShrinkSDK.EventBus"] = "2.1.0",
            ["ShrinkSDK.Context.Core"] = "0.2.0",
            ["ShrinkSDK.Command"] = "0.3.0",
            ["ShrinkSDK.Command.Integration.EventBus"] = "0.2.0",
            ["ShrinkSDK.Command.Integration.Network"] = "0.2.0",
            ["ShrinkSDK.Command.Integration.App"] = "0.2.0",
            ["ShrinkSDK.Network"] = "0.3.0",
            ["ShrinkSDK.Network.Integration.EventBus"] = "0.2.0",
            ["ShrinkSDK.Network.Integration.App"] = "0.2.0",
            ["ShrinkSDK.DataSaver"] = "2.3.0",
            ["ShrinkSDK.DataSaver.Integration.EventBus"] = "2.2.0",
            ["ShrinkSDK.DataSaver.Integration.App"] = "0.2.0",
            ["ShrinkSDK.App.Core"] = "0.2.0",
            ["ShrinkSDK.Context.AppAdapter"] = "0.2.0",
            ["ShrinkSDK.App.Starter.Basic"] = "0.3.0",
            ["ShrinkSDK.ModFramework"] = "0.3.0",
            ["ShrinkSDK.ModFramework.Godot"] = "0.1.0",
            ["ShrinkSDK.Tutorial"] = "0.2.0",
            ["ShrinkSDK.Tutorial.Godot"] = "0.1.0"
        };

    public static IReadOnlyDictionary<string, string> ReadPackageReferences(string projectPath)
    {
        var document = XDocument.Load(projectPath, LoadOptions.PreserveWhitespace);
        return document.Descendants("PackageReference")
            .Select(element => new
            {
                Id = ((string?)element.Attribute("Include") ?? (string?)element.Attribute("Update"))?.Trim(),
                Version = ((string?)element.Attribute("Version") ??
                           (string?)element.Attribute("VersionOverride") ??
                           element.Element("Version")?.Value)?.Trim() ?? string.Empty
            })
            .Where(item => !string.IsNullOrWhiteSpace(item.Id))
            .GroupBy(item => item.Id!, StringComparer.OrdinalIgnoreCase)
            .ToDictionary(group => group.Key, group => group.First().Version, StringComparer.OrdinalIgnoreCase);
    }

    public static void SetPackageReference(string projectPath, string packageId, string? version)
    {
        var document = XDocument.Load(projectPath, LoadOptions.PreserveWhitespace);
        var root = document.Root ?? throw new InvalidDataException("The C# project has no root element.");
        var references = root.Descendants("PackageReference").Where(element =>
            string.Equals((string?)element.Attribute("Include"), packageId, StringComparison.OrdinalIgnoreCase)).ToArray();
        foreach (var duplicate in references.Skip(1)) duplicate.Remove();
        if (string.IsNullOrWhiteSpace(version))
        {
            foreach (var reference in references) reference.Remove();
        }
        else if (references.Length > 0)
        {
            var reference = references[0];
            if (reference.Attribute("VersionOverride") != null)
                reference.SetAttributeValue("VersionOverride", version);
            else if (reference.Attribute("Version") != null)
                reference.SetAttributeValue("Version", version);
            else if (reference.Element("Version") != null)
                reference.Element("Version")!.Value = version;
            else
                reference.SetAttributeValue("Version", version);
        }
        else
        {
            var group = root.Elements("ItemGroup").FirstOrDefault(element => element.Elements("PackageReference").Any());
            if (group == null)
            {
                group = new XElement("ItemGroup");
                root.Add(group);
            }
            group.Add(new XElement("PackageReference", new XAttribute("Include", packageId), new XAttribute("Version", version)));
        }
        WriteAtomically(projectPath, document);
    }

    public static void EnsureShrinkFeed(string nugetConfigPath)
    {
        XDocument document;
        if (File.Exists(nugetConfigPath)) document = XDocument.Load(nugetConfigPath, LoadOptions.PreserveWhitespace);
        else document = new XDocument(new XDeclaration("1.0", "utf-8", null), new XElement("configuration"));
        var root = document.Root ?? throw new InvalidDataException("NuGet.Config has no root element.");
        var sources = root.Element("packageSources");
        if (sources == null)
        {
            sources = new XElement("packageSources");
            root.Add(sources);
        }
        var existing = sources.Elements("add").FirstOrDefault(element =>
            string.Equals((string?)element.Attribute("key"), "ShrinkSDK", StringComparison.OrdinalIgnoreCase));
        if (existing == null)
            sources.Add(new XElement("add", new XAttribute("key", "ShrinkSDK"),
                new XAttribute("value", "https://git.crash.work/api/packages/ShrinkSDK/nuget/index.json")));
        else
            existing.SetAttributeValue("value", "https://git.crash.work/api/packages/ShrinkSDK/nuget/index.json");
        WriteAtomically(nugetConfigPath, document);
    }

    public static async Task<(int ExitCode, string Output)> RunDotnetAsync(string projectDirectory,
        string arguments, CancellationToken cancellationToken = default)
    {
        var output = new StringBuilder();
        using var process = new Process
        {
            StartInfo = new ProcessStartInfo("dotnet", arguments)
            {
                WorkingDirectory = projectDirectory,
                UseShellExecute = false,
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                CreateNoWindow = true
            }
        };
        process.OutputDataReceived += (_, args) => { if (args.Data != null) output.AppendLine(args.Data); };
        process.ErrorDataReceived += (_, args) => { if (args.Data != null) output.AppendLine(args.Data); };
        process.Start();
        process.BeginOutputReadLine();
        process.BeginErrorReadLine();
        await process.WaitForExitAsync(cancellationToken);
        return (process.ExitCode, output.ToString());
    }

    private static void WriteAtomically(string path, XDocument document)
    {
        Directory.CreateDirectory(Path.GetDirectoryName(Path.GetFullPath(path))!);
        var temporaryPath = path + ".shrinksdk.tmp";
        using (var writer = new StreamWriter(temporaryPath, false, new UTF8Encoding(false)))
            document.Save(writer, SaveOptions.DisableFormatting);
        File.Move(temporaryPath, path, true);
    }
}