// Kyoo - A portable and vast media library solution.
// Copyright (c) Kyoo.
//
// See AUTHORS.md and LICENSE file in the project root for full license information.
//
// Kyoo is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// any later version.
//
// Kyoo is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Kyoo. If not, see <https://www.gnu.org/licenses/>.

using System;
using Kyoo.Abstractions.Controllers;
using Microsoft.AspNetCore.Mvc.Filters;
using Microsoft.Extensions.DependencyInjection;

namespace Kyoo.Abstractions.Models.Permissions;

/// <summary>
/// The kind of permission needed.
/// </summary>
public enum Kind
{
	/// <summary>
	/// Allow the user to read for this kind of data.
	/// </summary>
	Read,

	/// <summary>
	/// Allow the user to write for this kind of data.
	/// </summary>
	Write,

	/// <summary>
	/// Allow the user to create this kind of data.
	/// </summary>
	Create,

	/// <summary>
	/// Allow the user to delete this kind of data.
	/// </summary>
	Delete,

	/// <summary>
	/// Allow the user to play this file.
	/// </summary>
	Play,
}

/// <summary>
/// The group of the permission.
/// </summary>
public enum Group
{
	/// <summary>
	/// Default group indicating no value.
	/// </summary>
	None,

	/// <summary>
	/// Allow all operations on basic items types.
	/// </summary>
	Overall,

	/// <summary>
	/// Allow operation on sensitive items like libraries path, configurations and so on.
	/// </summary>
	Admin
}

/// <summary>
/// Specify permissions needed for the API.
/// </summary>
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true)]
public class PermissionAttribute : Attribute, IFilterFactory
{
	/// <summary>
	/// The needed permission as string.
	/// </summary>
	public string Type { get; }

	/// <summary>
	/// The needed permission kind.
	/// </summary>
	public Kind Kind { get; }

	/// <summary>
	/// The group of this permission.
	/// </summary>
	public Group Group { get; }

	/// <summary>
	/// Ask a permission to run an action.
	/// </summary>
	/// <param name="type">
	/// The type of the action
	/// </param>
	/// <param name="permission">
	/// The kind of permission needed.
	/// </param>
	/// <param name="group">
	/// The group of this permission (allow grouped permission like overall.read
	/// for all read permissions of this group).
	/// </param>
	public PermissionAttribute(string type, Kind permission, Group group = Group.Overall)
	{
		Type = type.ToLower();
		Kind = permission;
		Group = group;
	}

	/// <inheritdoc />
	public IFilterMetadata CreateInstance(IServiceProvider serviceProvider)
	{
		return serviceProvider.GetRequiredService<IPermissionValidator>().Create(this);
	}

	/// <inheritdoc />
	public bool IsReusable => true;

	/// <summary>
	/// Return this permission attribute as a string.
	/// </summary>
	/// <returns>The string representation.</returns>
	public string AsPermissionString()
	{
		return Type;
	}
}