using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Linq;
#if !UNITY_2020_1_OR_NEWER
using System.Reflection;
#endif
using System.Xml.Linq;
using UnityEditor;
using UnityEditor.PackageManager;
using UnityEngine;

namespace AppLovinMax.Scripts.IntegrationManager.Editor
{
    [Serializable]
    public class PackageInfo
    {
        // ReSharper disable InconsistentNaming - For JSON Deserialization
        public string Name;
        public string Version;
    }

    public interface IPackageManagerClient
    {
        IEnumerator AddNetwork(Network network, bool showImport);
        void RemoveNetwork(Network network);
    }

    public static class AppLovinPackageManager
    {
        private const string AppLovinMediationAmazonAdapterDependenciesPath = "Amazon/Scripts/Mediations/AppLovinMediation/Editor/Dependencies.xml";

#if UNITY_2019_2_OR_NEWER
        private static readonly IPackageManagerClient _upmPackageManager = new AppLovinUpmPackageManager();
#endif
        private static readonly IPackageManagerClient _assetsPackageManager = new AppLovinAssetsPackageManager();

        private static IPackageManagerClient PackageManagerClient
        {
            get
            {
#if UNITY_2019_2_OR_NEWER
                return AppLovinIntegrationManager.IsPluginInPackageManager ? _upmPackageManager : _assetsPackageManager;
#else
                return _assetsPackageManager;
#endif
            }
        }

        internal static PluginData PluginData { get; set; }

        /// <summary>
        /// Checks whether or not an adapter with the given version or newer exists.
        /// </summary>
        /// <param name="adapterName">The name of the network (the root adapter folder name in "MaxSdk/Mediation/" folder.</param>
        /// <param name="iosVersion">The min iOS adapter version to check for. Can be <c>null</c> if we want to check for any version.</param>
        /// <param name="androidVersion">The min android adapter version to check for. Can be <c>null</c> if we want to check for any version.</param>
        /// <returns><c>true</c> if an adapter with the min version is installed.</returns>
        internal static bool IsAdapterInstalled(string adapterName, string iosVersion = null, string androidVersion = null)
        {
            var dependencyFilePathList = GetAssetPathListForExportPath("MaxSdk/Mediation/" + adapterName + "/Editor/Dependencies.xml");
            if (dependencyFilePathList.Count <= 0) return false;

            var currentVersion = GetCurrentVersions(dependencyFilePathList);
            if (iosVersion != null)
            {
                var iosVersionComparison = MaxSdkUtils.CompareVersions(currentVersion.Ios, iosVersion);
                if (iosVersionComparison == MaxSdkUtils.VersionComparisonResult.Lesser)
                {
                    return false;
                }
            }

            if (androidVersion != null)
            {
                var androidVersionComparison = MaxSdkUtils.CompareVersions(currentVersion.Android, androidVersion);
                if (androidVersionComparison == MaxSdkUtils.VersionComparisonResult.Lesser)
                {
                    return false;
                }
            }

            return true;
        }

        /// <summary>
        /// Checks whether an adapter is installed using the plugin data.
        /// </summary>
        /// <param name="pluginData">The plugin data to check for the adapter</param>
        /// <param name="adapterName">The name of the network.</param>
        /// <returns>Whether an adapter is installed in the plugin data</returns>
        internal static bool IsAdapterInstalled(PluginData pluginData, string adapterName)
        {
            var network = pluginData.MediatedNetworks.Where(mediatedNetwork => mediatedNetwork.Name.Equals(adapterName)).ToList().FirstOrDefault();
            var networkVersion = network != null ? network.CurrentVersions : null;
            var currentVersion = networkVersion != null ? networkVersion.Unity : "";

            return MaxSdkUtils.IsValidString(currentVersion);
        }

        /// <summary>
        /// Gets the mediation networks that are currently installed in the project. If using UPM, checks
        /// for networks in Packages folder and Mediation folder in case a custom adapter was added to the project.
        /// </summary>
        /// <returns>A list of the installed mediation network names.</returns>
        internal static List<string> GetInstalledMediationNetworks()
        {
            var installedNetworks = new List<string>();
            var installedNetworksInAssets = AppLovinAssetsPackageManager.GetInstalledMediationNetworks();
            installedNetworks.AddRange(installedNetworksInAssets);

#if UNITY_2019_2_OR_NEWER
            var installedNetworksInPackages = AppLovinUpmPackageManager.GetInstalledMediationNetworks();
            installedNetworks.AddRange(installedNetworksInPackages);
#endif

            if (IsAmazonAppLovinAdapterInstalled())
            {
                installedNetworks.Add("AmazonAdMarketplace");
            }

            return installedNetworks;
        }

        /// <summary>
        /// Adds a network to the project.
        /// </summary>
        /// <param name="network">The network to add.</param>
        /// <param name="showImport">Whether to show the import window (only for non UPM)</param>
        internal static IEnumerator AddNetwork(Network network, bool showImport)
        {
            yield return PackageManagerClient.AddNetwork(network, showImport);

            AppLovinEditorCoroutine.StartCoroutine(RefreshAssetsAtEndOfFrame(network));
        }

        /// <summary>
        /// Removes a network from the project.
        /// </summary>
        /// <param name="network">The network to remove.</param>
        internal static void RemoveNetwork(Network network)
        {
            PackageManagerClient.RemoveNetwork(network);

            AppLovinEditorCoroutine.StartCoroutine(RefreshAssetsAtEndOfFrame(network));
        }

        #region Utility

        /// <summary>
        /// Gets the list of all asset paths for a given MAX plugin export path.
        /// </summary>
        /// <param name="exportPath">The actual exported path of the asset.</param>
        /// <returns>The exported path of the MAX plugin asset or an empty list if the asset is not found.</returns>
        private static List<string> GetAssetPathListForExportPath(string exportPath)
        {
            var assetLabelToFind = "l:al_max_export_path-" + exportPath.Replace(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar);
            var assetGuids = AssetDatabase.FindAssets(assetLabelToFind);

            var assetPaths = new List<string>();
            foreach (var assetGuid in assetGuids)
            {
                assetPaths.Add(AssetDatabase.GUIDToAssetPath(assetGuid));
            }

            return assetPaths.Count <= 0 ? new List<string>() : assetPaths;
        }

        /// <summary>
        /// Updates the CurrentVersion fields for a given network data object.
        /// </summary>
        /// <param name="network">Network for which to update the current versions.</param>
        internal static void UpdateCurrentVersions(Network network)
        {
            var assetPaths = GetAssetPathListForExportPath(network.DependenciesFilePath);
#if UNITY_2019_2_OR_NEWER
            if (HasDuplicateAdapters(assetPaths))
            {
                ShowDeleteDuplicateAdapterPrompt(network);
            }
#endif

            var currentVersions = GetCurrentVersions(assetPaths);
            network.CurrentVersions = currentVersions;

            // If AppLovin mediation plugin, get the version from MaxSdk and the latest and current version comparison.
            if (network.Name.Equals("APPLOVIN_NETWORK"))
            {
                network.CurrentVersions.Unity = MaxSdk.Version;

                var unityVersionComparison = MaxSdkUtils.CompareVersions(network.CurrentVersions.Unity, network.LatestVersions.Unity);
                var androidVersionComparison = MaxSdkUtils.CompareVersions(network.CurrentVersions.Android, network.LatestVersions.Android);
                var iosVersionComparison = MaxSdkUtils.CompareVersions(network.CurrentVersions.Ios, network.LatestVersions.Ios);

                // Overall version is same if all the current and latest (from db) versions are same.
                if (unityVersionComparison == MaxSdkUtils.VersionComparisonResult.Equal &&
                    androidVersionComparison == MaxSdkUtils.VersionComparisonResult.Equal &&
                    iosVersionComparison == MaxSdkUtils.VersionComparisonResult.Equal)
                {
                    network.CurrentToLatestVersionComparisonResult = MaxSdkUtils.VersionComparisonResult.Equal;
                }
                // One of the installed versions is newer than the latest versions which means that the publisher is on a beta version.
                else if (unityVersionComparison == MaxSdkUtils.VersionComparisonResult.Greater ||
                         androidVersionComparison == MaxSdkUtils.VersionComparisonResult.Greater ||
                         iosVersionComparison == MaxSdkUtils.VersionComparisonResult.Greater)
                {
                    network.CurrentToLatestVersionComparisonResult = MaxSdkUtils.VersionComparisonResult.Greater;
                }
                // We have a new version available if all Android, iOS and Unity has a newer version available in db.
                else
                {
                    network.CurrentToLatestVersionComparisonResult = MaxSdkUtils.VersionComparisonResult.Lesser;
                }
            }
            // For all other mediation adapters, get the version comparison using their Unity versions.
            else
            {
                // If adapter is indeed installed, compare the current (installed) and the latest (from db) versions, so that we can determine if the publisher is on an older, current or a newer version of the adapter.
                // If the publisher is on a newer version of the adapter than the db version, that means they are on a beta version.
                if (MaxSdkUtils.IsValidString(currentVersions.Unity))
                {
                    network.CurrentToLatestVersionComparisonResult = AppLovinIntegrationManagerUtils.CompareUnityMediationVersions(currentVersions.Unity, network.LatestVersions.Unity);
                }

                if (MaxSdkUtils.IsValidString(network.CurrentVersions.Unity) && AppLovinAutoUpdater.MinAdapterVersions.ContainsKey(network.Name))
                {
                    var comparisonResult = AppLovinIntegrationManagerUtils.CompareUnityMediationVersions(network.CurrentVersions.Unity, AppLovinAutoUpdater.MinAdapterVersions[network.Name]);
                    // Requires update if current version is lower than the min required version.
                    network.RequiresUpdate = comparisonResult < 0;
                }
                else
                {
                    // Reset value so that the Integration manager can hide the alert icon once adapter is updated.
                    network.RequiresUpdate = false;
                }
            }
        }

#if UNITY_2019_2_OR_NEWER
        /// <summary>
        /// Checks whether a network has duplicate adapters installed in both the Assets folder and via UPM.
        /// </summary>
        /// <param name="dependencyPaths">The list of paths to the dependencies.xml files</param>
        /// <returns><c>True</c> if there are adapters in both the Assets folder and installed via UPM</returns>
        private static bool HasDuplicateAdapters(List<string> dependencyPaths)
        {
            var inPackagesFolder = dependencyPaths.Any(path => path.Contains("Packages"));
            var inAssetsFolder = dependencyPaths.Any(path => path.Contains("Assets"));

            return inPackagesFolder && inAssetsFolder;
        }

        /// <summary>
        /// Displays a prompt informing the user that duplicate adapters were detected
        /// and allows them to choose which version to keep.
        /// </summary>
        /// <param name="network">The network that has duplicate adapters installed.</param>
        private static void ShowDeleteDuplicateAdapterPrompt(Network network)
        {
            var keepAssetsAdapter = EditorUtility.DisplayDialog("Duplicate Adapters Detected",
                "The " + network.DisplayName + " adapter is installed in both the Assets folder and via UPM. Please choose which version to keep.",
                "Keep Assets Folder Version",
                "Keep UPM Version");
            DeleteDuplicateAdapter(network, keepAssetsAdapter);
        }

        /// <summary>
        /// Removes a duplicate adapter by either deleting it from the Assets folder
        /// or uninstalling it from the Unity Package Manager (UPM).
        /// </summary>
        /// <param name="network">The network for which the duplicate adapter is being removed.</param>
        /// <param name="keepAssetsAdapter">If <c>true</c>, retains the adapter in the Assets folder and removes the UPM version;
        /// otherwise, deletes the adapter from the Assets folder.</param>
        internal static void DeleteDuplicateAdapter(Network network, bool keepAssetsAdapter)
        {
            if (keepAssetsAdapter)
            {
                var appLovinManifest = AppLovinUpmManifest.Load();
                AppLovinUpmPackageManager.RemovePackages(network, appLovinManifest);
                appLovinManifest.Save();
            }
            else
            {
                foreach (var pluginFilePath in network.PluginFilePaths)
                {
                    var filePath = Path.Combine(AppLovinIntegrationManager.MediationDirectory, pluginFilePath.Replace("MaxSdk/Mediation/", ""));
                    FileUtil.DeleteFileOrDirectory(filePath);
                    FileUtil.DeleteFileOrDirectory(filePath + ".meta");
                }
            }

            AppLovinUpmPackageManager.ResolvePackageManager();
        }
#endif

        /// <summary>
        /// Gets the current versions for a given network's dependency file paths. UPM will have multiple paths
        /// for each network - one each for iOS and Android.
        /// </summary>
        /// <param name="dependencyPaths">A list of dependency file paths to extract current versions from.</param>
        /// <returns>Current versions of a given network's dependency files.</returns>
        private static Versions GetCurrentVersions(List<string> dependencyPaths)
        {
            var currentVersions = new Versions();
            foreach (var dependencyPath in dependencyPaths)
            {
                GetCurrentVersion(currentVersions, dependencyPath);
            }

            if (currentVersions.Android != null && currentVersions.Ios != null)
            {
                currentVersions.Unity = "android_" + currentVersions.Android + "_ios_" + currentVersions.Ios;
            }
            else if (currentVersions.Android != null)
            {
                currentVersions.Unity = "android_" + currentVersions.Android;
            }
            else if (currentVersions.Ios != null)
            {
                currentVersions.Unity = "ios_" + currentVersions.Ios;
            }

            return currentVersions;
        }

        /// <summary>
        /// Extracts the current version of a network from its dependency.xml file.
        /// </summary>
        /// <param name="currentVersions">The Versions object we are using.</param>
        /// <param name="dependencyPath">The path to the dependency.xml file.</param>
        private static void GetCurrentVersion(Versions currentVersions, string dependencyPath)
        {
            XDocument dependency;
            try
            {
                dependency = XDocument.Load(dependencyPath);
            }
#pragma warning disable 0168
            catch (IOException exception)
#pragma warning restore 0168
            {
                // Couldn't find the dependencies file. The plugin is not installed.
                return;
            }

            // <dependencies>
            //  <androidPackages>
            //      <androidPackage spec="com.applovin.mediation:network_name-adapter:1.2.3.4" />
            //  </androidPackages>
            //  <iosPods>
            //      <iosPod name="AppLovinMediationNetworkNameAdapter" version="2.3.4.5" />
            //  </iosPods>
            // </dependencies>
            string androidVersion = null;
            string iosVersion = null;
            var dependenciesElement = dependency.Element("dependencies");
            if (dependenciesElement != null)
            {
                var androidPackages = dependenciesElement.Element("androidPackages");
                if (androidPackages != null)
                {
                    var adapterPackage = androidPackages.Descendants().FirstOrDefault(element => element.Name.LocalName.Equals("androidPackage")
                                                                                                 && element.FirstAttribute.Name.LocalName.Equals("spec")
                                                                                                 && element.FirstAttribute.Value.StartsWith("com.applovin"));
                    if (adapterPackage != null)
                    {
                        androidVersion = adapterPackage.FirstAttribute.Value.Split(':').Last();
                        // Hack alert: Some Android versions might have square brackets to force a specific version. Remove them if they are detected.
                        if (androidVersion.StartsWith("["))
                        {
                            androidVersion = androidVersion.Trim('[', ']');
                        }
                    }
                }

                var iosPods = dependenciesElement.Element("iosPods");
                if (iosPods != null)
                {
                    var adapterPod = iosPods.Descendants().FirstOrDefault(element => element.Name.LocalName.Equals("iosPod")
                                                                                     && element.FirstAttribute.Name.LocalName.Equals("name")
                                                                                     && element.FirstAttribute.Value.StartsWith("AppLovin"));
                    if (adapterPod != null)
                    {
                        iosVersion = adapterPod.Attributes().First(attribute => attribute.Name.LocalName.Equals("version")).Value;
                    }
                }
            }

            if (androidVersion != null)
            {
                currentVersions.Android = androidVersion;
            }

            if (iosVersion != null)
            {
                currentVersions.Ios = iosVersion;
            }
        }

        /// <summary>
        /// Check for the Amazon AppLovin adapter in the project.
        /// </summary>
        /// <returns>Whether the AppLovin Adapter is installed through the Amazon SDK.</returns>
        private static bool IsAmazonAppLovinAdapterInstalled()
        {
            string[] dependenciesFiles = AssetDatabase.FindAssets("t:TextAsset Dependencies", new[] {"Assets"})
                .Select(AssetDatabase.GUIDToAssetPath)
                .ToArray();

            // Use regex to search for Amazon and then AppLovin in the file paths of the dependencies.xml files.
            return dependenciesFiles.Any(filePath => filePath.Contains(AppLovinMediationAmazonAdapterDependenciesPath));
        }

        /// <summary>
        /// Refresh assets and update current versions after a slight delay to allow for Client.Resolve to finish.
        /// </summary>
        /// <param name="network">The network that was just installed/removed.</param>
        private static IEnumerator RefreshAssetsAtEndOfFrame(Network network)
        {
            yield return new WaitForEndOfFrame();
            UpdateCurrentVersions(network);
            AssetDatabase.Refresh();
        }

        #endregion
    }

#if UNITY_2019_2_OR_NEWER
    public class AppLovinUpmPackageManager : IPackageManagerClient
    {
        public const string PackageNamePrefixAppLovin = "com.applovin.mediation.ads";
        private const string PackageNamePrefixNetwork = "com.applovin.mediation.adapters";
        private const string PackageNamePrefixDsp = "com.applovin.mediation.dsp";

        private const float TimeoutFetchPackageCollectionSeconds = 10f;

#if !UNITY_2020_1_OR_NEWER
        private static Type packageManagerClientType;
        private static MethodInfo packageManagerResolveMethod;
#endif

        public static List<string> GetInstalledMediationNetworks()
        {
            // Return empty list if we failed to get the package list
            var packageCollection = GetPackageCollectionSync(TimeoutFetchPackageCollectionSeconds);
            if (packageCollection == null)
            {
                return new List<string>();
            }

            return packageCollection.Where(package => package.name.StartsWith(PackageNamePrefixNetwork) || package.name.StartsWith(PackageNamePrefixDsp))
                .SelectMany(package => package.keywords)
                .Where(keyword => keyword.StartsWith("dir:"))
                .Select(keyword => keyword.Replace("dir:", ""))
                .Distinct()
                .ToList();
        }

        public IEnumerator AddNetwork(Network network, bool showImport)
        {
            var appLovinManifest = AppLovinUpmManifest.Load();
            AddPackages(network, appLovinManifest);
            appLovinManifest.Save();

            // Remove any versions of the adapter in the Assets folder
            AppLovinPackageManager.DeleteDuplicateAdapter(network, false);
            ResolvePackageManager();

            yield break;
        }

        public void RemoveNetwork(Network network)
        {
            var appLovinManifest = AppLovinUpmManifest.Load();
            RemovePackages(network, appLovinManifest);
            appLovinManifest.Save();
            ResolvePackageManager();
        }

        /// <summary>
        /// Adds a network's packages to the package manager removes any beta version that exists
        /// </summary>
        /// <param name="network">The network to add.</param>
        /// <param name="appLovinManifest">The AppLovinUpmManifest instance to edit</param>
        internal static void AddPackages(Network network, AppLovinUpmManifest appLovinManifest)
        {
            foreach (var packageInfo in network.Packages)
            {
                appLovinManifest.AddPackageDependency(packageInfo.Name, packageInfo.Version);
                RemoveBetaPackage(packageInfo.Name, appLovinManifest);
            }
        }

        /// <summary>
        /// Removes a network's packages from the package manager
        /// </summary>
        /// <param name="network">The network to add.</param>
        /// <param name="appLovinManifest">The AppLovinUpmManifest instance to edit</param>
        internal static void RemovePackages(Network network, AppLovinUpmManifest appLovinManifest)
        {
            foreach (var packageInfo in network.Packages)
            {
                appLovinManifest.RemovePackageDependency(packageInfo.Name);
                RemoveBetaPackage(packageInfo.Name, appLovinManifest);
            }
        }

        /// <summary>
        /// Removes the beta version of a package name
        /// </summary>
        /// <param name="packageName">The name of the package to remove a beta for</param>
        /// <param name="appLovinManifest">The AppLovinUpmManifest instance to edit</param>
        private static void RemoveBetaPackage(string packageName, AppLovinUpmManifest appLovinManifest)
        {
            var prefix = "";
            if (packageName.Contains(PackageNamePrefixNetwork))
            {
                prefix = PackageNamePrefixNetwork;
            }
            else if (packageName.Contains(PackageNamePrefixDsp))
            {
                prefix = PackageNamePrefixDsp;
            }
            else if (packageName.Contains(PackageNamePrefixAppLovin))
            {
                prefix = PackageNamePrefixAppLovin;
            }
            else
            {
                return;
            }

            var betaPackageName = packageName.Replace(prefix, prefix + ".beta");
            appLovinManifest.RemovePackageDependency(betaPackageName);
        }

        /// <summary>
        /// Resolves the Unity Package Manager so any changes made to the manifest.json file are reflected in the Unity Editor.
        /// </summary>
        internal static void ResolvePackageManager()
        {
#if UNITY_2020_1_OR_NEWER
            Client.Resolve();
#else
            packageManagerClientType = packageManagerClientType ?? typeof(Client);
            if (packageManagerClientType != null)
            {
                packageManagerResolveMethod = packageManagerResolveMethod ?? packageManagerClientType.GetMethod("Resolve", BindingFlags.NonPublic | BindingFlags.Static);
            }

            if (packageManagerResolveMethod != null)
            {
                packageManagerResolveMethod.Invoke(null, null);
            }
#endif
        }

        /// <summary>
        /// Gets the PackageCollection from the Unity Package Manager synchronously.
        /// </summary>
        /// <param name="timeoutSeconds">How long to wait before exiting with a timeout error</param>
        /// <returns></returns>
        private static PackageCollection GetPackageCollectionSync(float timeoutSeconds = -1)
        {
            var request = Client.List();

            // Just wait till the request is complete
            var now = DateTime.Now;
            while (!request.IsCompleted)
            {
                // Wait indefinitely if there is no timeout set.
                if (timeoutSeconds < 0) continue;

                var delta = DateTime.Now - now;
                if (delta.TotalSeconds > timeoutSeconds)
                {
                    MaxSdkLogger.UserError("Failed to list UPM packages: Timeout");
                    break;
                }
            }

            if (!request.IsCompleted)
            {
                return null;
            }

            if (request.Status >= StatusCode.Failure)
            {
                MaxSdkLogger.UserError("Failed to list packages: " + request.Error.message);
                return null;
            }

            return (request.Status == StatusCode.Success) ? request.Result : null;
        }
    }

#endif

    public class AppLovinAssetsPackageManager : IPackageManagerClient
    {
        public static List<string> GetInstalledMediationNetworks()
        {
            var maxMediationDirectory = AppLovinIntegrationManager.MediationDirectory;
            if (!Directory.Exists(maxMediationDirectory)) return new List<string>();

            var mediationNetworkDirectories = Directory.GetDirectories(maxMediationDirectory);
            return mediationNetworkDirectories.Select(Path.GetFileName).ToList();
        }

        public IEnumerator AddNetwork(Network network, bool showImport)
        {
            yield return AppLovinIntegrationManager.Instance.DownloadPlugin(network, showImport);
        }

        public void RemoveNetwork(Network network)
        {
            foreach (var pluginFilePath in network.PluginFilePaths)
            {
                var filePath = Path.Combine(AppLovinIntegrationManager.PluginParentDirectory, pluginFilePath);
                FileUtil.DeleteFileOrDirectory(filePath);
                FileUtil.DeleteFileOrDirectory(filePath + ".meta");
            }
        }
    }
}