using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using Umbraco.Cms.Core;
using Umbraco.Cms.Core.Models.Membership;
using Umbraco.Cms.Core.Services;

namespace Umbraco.Extensions
{
    public static class UserServiceExtensions
    {
        public static EntityPermission GetPermissions(this IUserService userService, IUser user, string path)
        {
            var ids = path.Split(Constants.CharArrays.Comma, StringSplitOptions.RemoveEmptyEntries)
                .Select(x => int.TryParse(x, NumberStyles.Integer, CultureInfo.InvariantCulture, out var value) ? Attempt<int>.Succeed(value) : Attempt<int>.Fail())
                .Where(x => x.Success)
                .Select(x=>x.Result)
                .ToArray();
            if (ids.Length == 0) throw new InvalidOperationException("The path: " + path + " could not be parsed into an array of integers or the path was empty");

            return userService.GetPermissions(user, ids[ids.Length - 1]).FirstOrDefault();
        }

        /// <summary>
        /// Get explicitly assigned permissions for a group and optional node Ids
        /// </summary>
        /// <param name="service"></param>
        /// <param name="group"></param>
        /// <param name="fallbackToDefaultPermissions">
        ///     Flag indicating if we want to include the default group permissions for each result if there are not explicit permissions set
        /// </param>
        /// <param name="nodeIds">Specifying nothing will return all permissions for all nodes</param>
        /// <returns>An enumerable list of <see cref="EntityPermission"/></returns>
        public static EntityPermissionCollection GetPermissions(this IUserService service, IUserGroup group, bool fallbackToDefaultPermissions, params int[] nodeIds)
        {
            return service.GetPermissions(new[] {group}, fallbackToDefaultPermissions, nodeIds);
        }

        /// <summary>
        /// Gets the permissions for the provided group and path
        /// </summary>
        /// <param name="service"></param>
        /// <param name="group"></param>
        /// <param name="path">Path to check permissions for</param>
        /// <param name="fallbackToDefaultPermissions">
        ///     Flag indicating if we want to include the default group permissions for each result if there are not explicit permissions set
        /// </param>
        public static EntityPermissionSet GetPermissionsForPath(this IUserService service, IUserGroup group, string path, bool fallbackToDefaultPermissions = false)
        {
            return service.GetPermissionsForPath(new[] { group }, path, fallbackToDefaultPermissions);
        }

        /// <summary>
        /// Remove all permissions for this user group for all nodes specified
        /// </summary>
        /// <param name="userService"></param>
        /// <param name="groupId"></param>
        /// <param name="entityIds"></param>
        public static void RemoveUserGroupPermissions(this IUserService userService, int groupId, params int[] entityIds)
        {
            userService.ReplaceUserGroupPermissions(groupId, new char[] {}, entityIds);
        }

        /// <summary>
        /// Remove all permissions for this user group for all nodes
        /// </summary>
        /// <param name="userService"></param>
        /// <param name="groupId"></param>
        public static void RemoveUserGroupPermissions(this IUserService userService, int groupId)
        {
            userService.ReplaceUserGroupPermissions(groupId, new char[] { });
        }


        public static IEnumerable<IProfile> GetProfilesById(this IUserService userService, params int[] ids)
        {
            var fullUsers = userService.GetUsersById(ids);

            return fullUsers.Select(user =>
            {
                var asProfile = user as IProfile;
                return asProfile ?? new UserProfile(user.Id, user.Name);
            });

        }
    }
}