#if UNITY_EDITOR
#nullable enable

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

namespace ShrinkSDK.WorkspaceValidation
{
    public static class ShrinkSdkWorkspaceValidation
    {
        private static readonly ExpectedPackage[] ExpectedPackages =
        {
            new ExpectedPackage("ShrinkApp.Core", "com.cneicy.shrink-app-core", "0.1.2"),
            new ExpectedPackage("ShrinkApp.Starter.Basic", "com.cneicy.shrink-app-starter-basic", "0.2.0"),
            new ExpectedPackage("ShrinkCommand", "com.cneicy.shrink-command", "0.2.0"),
            new ExpectedPackage("ShrinkCommand.Integration.App", "com.cneicy.shrink-command-integration-app", "0.1.1"),
            new ExpectedPackage("ShrinkCommand.Integration.EventBus", "com.cneicy.shrink-command-integration-eventbus", "0.1.1"),
            new ExpectedPackage("ShrinkCommand.Integration.Network", "com.cneicy.shrink-command-integration-network", "0.1.1"),
            new ExpectedPackage("ShrinkContext.AppAdapter", "com.cneicy.shrink-context-app-adapter", "0.1.3"),
            new ExpectedPackage("ShrinkContext.Core", "com.cneicy.shrink-context-core", "0.1.0"),
            new ExpectedPackage("ShrinkContext.EventBusAdapter", "com.cneicy.shrink-context-eventbus-adapter", "0.1.0"),
            new ExpectedPackage("ShrinkDataSaver", "com.cneicy.shrink-datasaver", "2.2.1"),
            new ExpectedPackage("ShrinkDataSaver.Integration.App", "com.cneicy.shrink-datasaver-integration-app", "0.1.1"),
            new ExpectedPackage("ShrinkDataSaver.Integration.EventBus", "com.cneicy.shrink-datasaver-integration-eventbus", "2.1.1"),
            new ExpectedPackage("ShrinkEventBus", "com.cneicy.shrink-eventbus", "2.0.0"),
            new ExpectedPackage("ShrinkEventBus.Entities", "com.cneicy.shrink-eventbus-entities", "0.1.0"),
            new ExpectedPackage("ShrinkInstaller", "com.cneicy.shrink-installer", "0.2.2"),
            new ExpectedPackage("ShrinkModFramework", "com.cneicy.shrink-mod-framework", "0.2.2"),
            new ExpectedPackage("ShrinkNetwork", "com.cneicy.shrink-network", "0.2.1"),
            new ExpectedPackage("ShrinkNetwork.Integration.App", "com.cneicy.shrink-network-integration-app", "0.1.1"),
            new ExpectedPackage("ShrinkNetwork.Integration.EventBus", "com.cneicy.shrink-network-integration-eventbus", "0.1.2"),
            new ExpectedPackage("ShrinkShared.CodeGen", "com.cneicy.shrink-shared-codegen", "0.1.0"),
            new ExpectedPackage("ShrinkTutorial", "com.cneicy.shrink-tutorial", "0.1.2")
        };

        public static void Run()
        {
            try
            {
                var workspaceRoot = Path.GetFullPath(Path.Combine(Application.dataPath, ".."));
                var packages = ReadPackages(workspaceRoot);
                ValidateGraph(packages);
                Debug.Log($"ShrinkSDK Workspace validation passed: packages={packages.Count}");
                EditorApplication.Exit(0);
            }
            catch (Exception exception)
            {
                Debug.LogException(exception);
                EditorApplication.Exit(1);
            }
        }

        private static Dictionary<string, PackageDefinition> ReadPackages(string workspaceRoot)
        {
            var result = new Dictionary<string, PackageDefinition>(StringComparer.Ordinal);
            foreach (var expected in ExpectedPackages)
            {
                var manifestPath = Path.Combine(workspaceRoot, "Assets", "Modules", expected.Directory, "package.json");
                if (!File.Exists(manifestPath))
                {
                    throw new FileNotFoundException($"Required package manifest is missing: {expected.Directory}", manifestPath);
                }

                var manifest = JObject.Parse(File.ReadAllText(manifestPath));
                var packageName = manifest.Value<string>("name");
                var version = manifest.Value<string>("version");
                if (packageName == null || version == null || packageName.Length == 0 || version.Length == 0)
                {
                    throw new InvalidOperationException($"{expected.Directory} has no valid package name or version.");
                }

                if (!string.Equals(packageName, expected.Name, StringComparison.Ordinal) ||
                    !string.Equals(version, expected.Version, StringComparison.Ordinal))
                {
                    throw new InvalidOperationException(
                        $"{expected.Directory} must be {expected.Name}@{expected.Version}, found {packageName}@{version}.");
                }

                if (result.ContainsKey(packageName))
                {
                    throw new InvalidOperationException($"Duplicate package manifest name: {packageName}");
                }

                result.Add(packageName, new PackageDefinition(packageName, version, manifest));
            }

            return result;
        }

        private static void ValidateGraph(IReadOnlyDictionary<string, PackageDefinition> packages)
        {
            var dependencies = new Dictionary<string, HashSet<string>>(StringComparer.Ordinal);
            foreach (var package in packages.Values)
            {
                var localDependencies = new HashSet<string>(StringComparer.Ordinal);
                var manifestDependencies = package.Manifest["dependencies"] as JObject;
                if (manifestDependencies != null)
                {
                    foreach (var property in manifestDependencies.Properties())
                    {
                        if (!packages.TryGetValue(property.Name, out var dependency))
                        {
                            continue;
                        }

                        var expectedVersion = property.Value.Value<string>();
                        if (!string.Equals(expectedVersion, dependency.Version, StringComparison.Ordinal))
                        {
                            throw new InvalidOperationException(
                                $"{package.Name} requires {dependency.Name} {expectedVersion}, but the Workspace provides {dependency.Version}.");
                        }

                        var isIntegrationOrStarter =
                            package.Name.IndexOf("-integration-", StringComparison.Ordinal) >= 0 ||
                            package.Name.IndexOf("-starter-", StringComparison.Ordinal) >= 0;
                        if (dependency.Name.IndexOf("-integration-", StringComparison.Ordinal) >= 0 && !isIntegrationOrStarter)
                        {
                            throw new InvalidOperationException(
                                $"{package.Name} must not depend on integration package {dependency.Name}.");
                        }

                        localDependencies.Add(dependency.Name);
                    }
                }

                dependencies.Add(package.Name, localDependencies);
            }

            var resolved = new HashSet<string>(StringComparer.Ordinal);
            var madeProgress = true;
            while (madeProgress)
            {
                madeProgress = false;
                foreach (var packageName in dependencies.Keys.OrderBy(name => name, StringComparer.Ordinal))
                {
                    if (resolved.Contains(packageName) || dependencies[packageName].Any(dependency => !resolved.Contains(dependency)))
                    {
                        continue;
                    }

                    resolved.Add(packageName);
                    madeProgress = true;
                }
            }

            if (resolved.Count != packages.Count)
            {
                var blocked = dependencies
                    .Where(pair => !resolved.Contains(pair.Key))
                    .Select(pair => pair.Key + " -> " + string.Join(", ", pair.Value.Where(dependency => !resolved.Contains(dependency))))
                    .OrderBy(value => value, StringComparer.Ordinal);
                throw new InvalidOperationException("Circular internal package dependencies detected: " + string.Join("; ", blocked));
            }
        }

        private sealed class PackageDefinition
        {
            public PackageDefinition(string name, string version, JObject manifest)
            {
                Name = name;
                Version = version;
                Manifest = manifest;
            }

            public string Name { get; }
            public string Version { get; }
            public JObject Manifest { get; }
        }

        private readonly struct ExpectedPackage
        {
            public ExpectedPackage(string directory, string name, string version)
            {
                Directory = directory;
                Name = name;
                Version = version;
            }

            public string Directory { get; }
            public string Name { get; }
            public string Version { get; }
        }
    }
}
#endif