#if UNITY_EDITOR
#nullable enable

using System;
using System.Linq;
using UnityEditor;
using UnityEditor.PackageManager;
using UnityEditor.PackageManager.Requests;
using UnityEngine;

namespace ShrinkSDK.Installer
{
    internal sealed class ShrinkSdkInstallerWindow : EditorWindow
    {
        private AddRequest? _addRequest;
        private ListRequest? _listRequest;
        private ResolveRequest? _resolveRequest;
        private ShrinkSdkPackageEntry? _pendingInstall;
        private int _selectedPackageIndex;
        private string _status = "Ready";
        private MessageType _statusType = MessageType.Info;

        [MenuItem("ShrinkSDK/Packages")]
        private static void Open()
        {
            GetWindow<ShrinkSdkInstallerWindow>("ShrinkSDK Packages");
        }

        private void OnEnable()
        {
            RefreshDiagnostics();
        }

        private void OnGUI()
        {
            EditorGUILayout.LabelField("ShrinkSDK", EditorStyles.boldLabel);
            EditorGUILayout.Space(4f);
            EditorGUILayout.LabelField("Registry", ShrinkSdkManifestStore.HasShrinkSdkRegistry()
                ? ShrinkSdkPackageCatalog.RegistryUrl
                : "Not configured");

            using (new EditorGUI.DisabledScope(IsBusy))
            {
                if (GUILayout.Button("Configure Registry"))
                {
                    ConfigureRegistry();
                }

                EditorGUILayout.Space(8f);
                if (GUILayout.Button("Install Starter Basic"))
                {
                    BeginInstall(ShrinkSdkPackageCatalog.StarterBasic);
                }

                var labels = ShrinkSdkPackageCatalog.Packages.Select(entry =>
                    entry.DisplayName + " " + entry.Version).ToArray();
                _selectedPackageIndex = EditorGUILayout.Popup("Package", _selectedPackageIndex, labels);
                if (GUILayout.Button("Install Selected Package"))
                {
                    BeginInstall(ShrinkSdkPackageCatalog.Packages[_selectedPackageIndex]);
                }

                if (GUILayout.Button("Refresh Diagnostics"))
                {
                    RefreshDiagnostics();
                }
            }

            EditorGUILayout.Space(8f);
            EditorGUILayout.HelpBox(_status, _statusType);
        }

        private bool IsBusy => _resolveRequest != null || _addRequest != null || _listRequest != null;

        private void Update()
        {
            if (_resolveRequest != null && _resolveRequest.IsCompleted)
            {
                var request = _resolveRequest;
                _resolveRequest = null;
                if (request.Status != StatusCode.Success)
                {
                    SetStatus("Registry resolve failed: " + request.Error.message, MessageType.Error);
                    return;
                }

                if (_pendingInstall != null)
                {
                    _addRequest = Client.Add(_pendingInstall.PackageSpecifier);
                    SetStatus("Installing " + _pendingInstall.PackageSpecifier, MessageType.Info);
                }
            }

            if (_addRequest != null && _addRequest.IsCompleted)
            {
                var request = _addRequest;
                _addRequest = null;
                if (request.Status == StatusCode.Success)
                {
                    SetStatus("Installed " + request.Result.name + " " + request.Result.version, MessageType.Info);
                }
                else
                {
                    SetStatus("Package install failed: " + request.Error.message, MessageType.Error);
                }

                _pendingInstall = null;
            }

            if (_listRequest != null && _listRequest.IsCompleted)
            {
                var request = _listRequest;
                _listRequest = null;
                if (request.Status == StatusCode.Success)
                {
                    var installed = request.Result.Count(package => package.name.StartsWith("com.cneicy.", StringComparison.Ordinal));
                    SetStatus("Registry is configured. Installed ShrinkSDK packages: " + installed, MessageType.Info);
                }
                else
                {
                    SetStatus("Package diagnostics failed: " + request.Error.message, MessageType.Warning);
                }
            }
        }

        private void ConfigureRegistry()
        {
            try
            {
                ShrinkSdkManifestStore.EnsureShrinkSdkRegistry();
                _pendingInstall = null;
                _resolveRequest = Client.Resolve();
                SetStatus("Registry configuration written. Resolving packages.", MessageType.Info);
            }
            catch (Exception exception)
            {
                SetStatus(exception.Message, MessageType.Error);
            }
        }

        private void BeginInstall(ShrinkSdkPackageEntry entry)
        {
            try
            {
                ShrinkSdkManifestStore.EnsureShrinkSdkRegistry();
                _pendingInstall = entry;
                _resolveRequest = Client.Resolve();
                SetStatus("Resolving registry for " + entry.PackageSpecifier, MessageType.Info);
            }
            catch (Exception exception)
            {
                SetStatus(exception.Message, MessageType.Error);
            }
        }

        private void RefreshDiagnostics()
        {
            if (IsBusy)
            {
                return;
            }

            _listRequest = Client.List(true);
            SetStatus("Refreshing installed package diagnostics.", MessageType.Info);
        }

        private void SetStatus(string message, MessageType messageType)
        {
            _status = message;
            _statusType = messageType;
            Repaint();
        }
    }
}
#endif