using System.Windows.Input;
using JdeScoping.SecureStoreManager.Constants;

namespace JdeScoping.SecureStoreManager.ViewModels;

/// <summary>
/// View model for creating a new store.
/// </summary>
public class NewStoreDialogViewModel : ViewModelBase
{
    private string _storePath = string.Empty;
    private string _keyFilePath = string.Empty;

    /// <summary>
    /// Initializes a new instance of the <see cref="NewStoreDialogViewModel"/> class.
    /// </summary>
    public NewStoreDialogViewModel()
    {
        BrowseStorePathCommand = new RelayCommand(BrowseStorePath);
        BrowseKeyFilePathCommand = new RelayCommand(BrowseKeyFilePath);
    }

    /// <summary>
    /// Gets or sets the path to the store file to create.
    /// </summary>
    public string StorePath
    {
        get => _storePath;
        set
        {
            if (SetProperty(ref _storePath, value))
                NotifyValidationChanged();
        }
    }

    /// <summary>
    /// Gets or sets the path to the key file for encryption.
    /// </summary>
    public string KeyFilePath
    {
        get => _keyFilePath;
        set
        {
            if (SetProperty(ref _keyFilePath, value))
                NotifyValidationChanged();
        }
    }

    private void NotifyValidationChanged()
    {
        OnPropertyChanged(nameof(IsValid));
        OnPropertyChanged(nameof(ValidationError));
    }

    /// <summary>
    /// Gets the command to browse for store path location.
    /// </summary>
    public ICommand BrowseStorePathCommand { get; }

    /// <summary>
    /// Gets the command to browse for key file path location.
    /// </summary>
    public ICommand BrowseKeyFilePathCommand { get; }

    /// <summary>
    /// Gets a value indicating whether the dialog input is valid.
    /// </summary>
    public bool IsValid => !string.IsNullOrWhiteSpace(StorePath) && !string.IsNullOrWhiteSpace(KeyFilePath);

    /// <summary>
    /// Gets the validation error message, or null if valid.
    /// </summary>
    public string? ValidationError
    {
        get
        {
            if (string.IsNullOrWhiteSpace(StorePath))
                return DialogStrings.StorePathRequired;

            if (string.IsNullOrWhiteSpace(KeyFilePath))
                return DialogStrings.KeyFilePathRequired;

            return null;
        }
    }

    /// <summary>
    /// Event raised to request save file dialog for store path.
    /// Parameters: title, fileTypeName, pattern, defaultExtension
    /// Returns: selected file path or null
    /// </summary>
    public event Func<string, string, string, string, Task<string?>>? OnShowSaveFileDialog;

    private async void BrowseStorePath()
    {
        if (OnShowSaveFileDialog == null)
            return;

        var path = await OnShowSaveFileDialog(
            DialogStrings.ChooseStoreLocation,
            FileExtensions.StoreTypeName,
            FileExtensions.StorePattern,
            FileExtensions.StoreExtension);
        if (!string.IsNullOrEmpty(path))
        {
            StorePath = path;
        }
    }

    private async void BrowseKeyFilePath()
    {
        if (OnShowSaveFileDialog == null)
            return;

        var path = await OnShowSaveFileDialog(
            DialogStrings.ChooseKeyFileLocation,
            FileExtensions.KeyTypeName,
            FileExtensions.KeyPattern,
            FileExtensions.KeyExtension);
        if (!string.IsNullOrEmpty(path))
        {
            KeyFilePath = path;
        }
    }
}

/// <summary>
/// View model for opening an existing store.
/// </summary>
public class OpenStoreDialogViewModel : ViewModelBase
{
    private string _storePath = string.Empty;
    private string _keyFilePath = string.Empty;

    /// <summary>
    /// Initializes a new instance of the <see cref="OpenStoreDialogViewModel"/> class.
    /// </summary>
    public OpenStoreDialogViewModel()
    {
        BrowseStorePathCommand = new RelayCommand(BrowseStorePath);
        BrowseKeyFilePathCommand = new RelayCommand(BrowseKeyFilePath);
    }

    /// <summary>
    /// Gets or sets the path to the store file to open.
    /// </summary>
    public string StorePath
    {
        get => _storePath;
        set
        {
            if (SetProperty(ref _storePath, value))
                NotifyValidationChanged();
        }
    }

    /// <summary>
    /// Gets or sets the path to the key file for decryption.
    /// </summary>
    public string KeyFilePath
    {
        get => _keyFilePath;
        set
        {
            if (SetProperty(ref _keyFilePath, value))
                NotifyValidationChanged();
        }
    }

    private void NotifyValidationChanged()
    {
        OnPropertyChanged(nameof(IsValid));
        OnPropertyChanged(nameof(ValidationError));
    }

    /// <summary>
    /// Gets the command to browse for store path location.
    /// </summary>
    public ICommand BrowseStorePathCommand { get; }

    /// <summary>
    /// Gets the command to browse for key file path location.
    /// </summary>
    public ICommand BrowseKeyFilePathCommand { get; }

    /// <summary>
    /// Gets a value indicating whether the dialog input is valid.
    /// </summary>
    public bool IsValid
    {
        get
        {
            if (string.IsNullOrWhiteSpace(StorePath))
                return false;

            return !string.IsNullOrWhiteSpace(KeyFilePath);
        }
    }

    /// <summary>
    /// Gets the validation error message, or null if valid.
    /// </summary>
    public string? ValidationError
    {
        get
        {
            if (string.IsNullOrWhiteSpace(StorePath))
                return DialogStrings.StorePathRequired;

            if (!System.IO.File.Exists(StorePath))
                return DialogStrings.StoreFileNotFound;

            if (string.IsNullOrWhiteSpace(KeyFilePath))
                return DialogStrings.KeyFilePathRequired;

            if (!System.IO.File.Exists(KeyFilePath))
                return DialogStrings.KeyFileNotFound;

            return null;
        }
    }

    /// <summary>
    /// Event raised to request open file dialog for store path.
    /// Parameters: title, fileTypeName, pattern
    /// Returns: selected file path or null
    /// </summary>
    public event Func<string, string, string, Task<string?>>? OnShowOpenFileDialog;

    private async void BrowseStorePath()
    {
        if (OnShowOpenFileDialog == null)
            return;

        var path = await OnShowOpenFileDialog(
            DialogStrings.SelectStoreFile,
            FileExtensions.StoreTypeName,
            FileExtensions.StorePattern);
        if (!string.IsNullOrEmpty(path))
        {
            StorePath = path;
        }
    }

    private async void BrowseKeyFilePath()
    {
        if (OnShowOpenFileDialog == null)
            return;

        var path = await OnShowOpenFileDialog(
            DialogStrings.SelectKeyFile,
            FileExtensions.KeyTypeName,
            FileExtensions.KeyPattern);
        if (!string.IsNullOrEmpty(path))
        {
            KeyFilePath = path;
        }
    }
}

/// <summary>
/// View model for adding or editing a secret.
/// </summary>
public class SecretEditDialogViewModel : ViewModelBase
{
    private string _key = string.Empty;
    private string _value = string.Empty;
    private bool _isNewSecret = true;

    /// <summary>
    /// Initializes a new instance of the <see cref="SecretEditDialogViewModel"/> class.
    /// </summary>
    public SecretEditDialogViewModel()
    {
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="SecretEditDialogViewModel"/> class with a key and value for editing.
    /// </summary>
    /// <param name="key">The secret key.</param>
    /// <param name="value">The secret value.</param>
    public SecretEditDialogViewModel(string key, string value)
    {
        _key = key;
        _value = value;
        _isNewSecret = false;
    }

    /// <summary>
    /// Gets or sets the secret key.
    /// </summary>
    public string Key
    {
        get => _key;
        set
        {
            if (SetProperty(ref _key, value))
                NotifyValidationChanged();
        }
    }

    /// <summary>
    /// Gets or sets the secret value.
    /// </summary>
    public string Value
    {
        get => _value;
        set => SetProperty(ref _value, value);
    }

    /// <summary>
    /// Gets or sets a value indicating whether this is a new secret being added.
    /// </summary>
    public bool IsNewSecret
    {
        get => _isNewSecret;
        set => SetProperty(ref _isNewSecret, value);
    }

    /// <summary>
    /// Gets a value indicating whether the key field is editable.
    /// </summary>
    public bool IsKeyEditable => _isNewSecret;

    /// <summary>
    /// Gets the dialog title based on whether this is a new secret or edit.
    /// </summary>
    public string DialogTitle => _isNewSecret ? "Add Secret" : "Edit Secret";

    /// <summary>
    /// Gets a value indicating whether the dialog input is valid.
    /// </summary>
    public bool IsValid => !string.IsNullOrWhiteSpace(Key);

    /// <summary>
    /// Gets the validation error message, or null if valid.
    /// </summary>
    public string? ValidationError
    {
        get
        {
            if (string.IsNullOrWhiteSpace(Key))
                return DialogStrings.KeyRequired;

            return null;
        }
    }

    private void NotifyValidationChanged()
    {
        OnPropertyChanged(nameof(IsValid));
        OnPropertyChanged(nameof(ValidationError));
    }
}