using Microsoft.Win32;

namespace Plandent.MstscScriptHook.Configurator;

internal static class RegistryConfig
{
    public const string ConfigKeyPath = @"Software\Plandent\MstscScriptHook";
    public const string AddInKeyPath = @"Software\Microsoft\Terminal Server Client\Default\AddIns\PlandentMstscScriptHook";

    public static HookConfig Load()
    {
        var config = new HookConfig();
        using RegistryKey? key = Registry.CurrentUser.OpenSubKey(ConfigKeyPath, writable: false);
        if (key is null)
        {
            return config;
        }

        config.Enabled = ReadBool(key, "Enabled", true);
        config.ScriptPath = ReadString(key, "ScriptPath");
        config.Arguments = ReadString(key, "Arguments");
        config.WorkingDirectory = ReadString(key, "WorkingDirectory");
        config.StartOnConnect = ReadBool(key, "StartOnConnect", true);
        config.StopOnDisconnect = ReadBool(key, "StopOnDisconnect", false);
        config.Hidden = ReadBool(key, "Hidden", true);
        config.PreventDuplicates = ReadBool(key, "PreventDuplicates", true);
        config.EnableLogging = ReadBool(key, "EnableLogging", true);
        return config;
    }

    public static void Save(HookConfig config)
    {
        using RegistryKey key = Registry.CurrentUser.CreateSubKey(ConfigKeyPath, writable: true)
            ?? throw new InvalidOperationException("Registry-Schlüssel konnte nicht erstellt werden.");

        key.SetValue("Enabled", config.Enabled ? 1 : 0, RegistryValueKind.DWord);
        key.SetValue("ScriptPath", config.ScriptPath ?? string.Empty, RegistryValueKind.ExpandString);
        key.SetValue("Arguments", config.Arguments ?? string.Empty, RegistryValueKind.String);
        key.SetValue("WorkingDirectory", config.WorkingDirectory ?? string.Empty, RegistryValueKind.ExpandString);
        key.SetValue("StartOnConnect", config.StartOnConnect ? 1 : 0, RegistryValueKind.DWord);
        key.SetValue("StopOnDisconnect", config.StopOnDisconnect ? 1 : 0, RegistryValueKind.DWord);
        key.SetValue("Hidden", config.Hidden ? 1 : 0, RegistryValueKind.DWord);
        key.SetValue("PreventDuplicates", config.PreventDuplicates ? 1 : 0, RegistryValueKind.DWord);
        key.SetValue("EnableLogging", config.EnableLogging ? 1 : 0, RegistryValueKind.DWord);
    }

    public static string? GetRegisteredPluginPath()
    {
        using RegistryKey? key = Registry.CurrentUser.OpenSubKey(AddInKeyPath, writable: false);
        return key?.GetValue("Name", null, RegistryValueOptions.DoNotExpandEnvironmentNames) as string;
    }

    public static void RegisterPlugin(string dllPath)
    {
        using RegistryKey key = Registry.CurrentUser.CreateSubKey(AddInKeyPath, writable: true)
            ?? throw new InvalidOperationException("MSTSC AddIn-Registry-Schlüssel konnte nicht erstellt werden.");
        key.SetValue("Name", dllPath, RegistryValueKind.String);
    }

    public static void UnregisterPlugin()
    {
        Registry.CurrentUser.DeleteSubKeyTree(AddInKeyPath, throwOnMissingSubKey: false);
    }

    private static bool ReadBool(RegistryKey key, string name, bool defaultValue)
    {
        object? value = key.GetValue(name);
        return value switch
        {
            int i => i != 0,
            long l => l != 0,
            _ => defaultValue
        };
    }

    private static string ReadString(RegistryKey key, string name, string defaultValue = "")
    {
        return key.GetValue(name, defaultValue, RegistryValueOptions.DoNotExpandEnvironmentNames) as string
            ?? defaultValue;
    }
}