using System;
using System.Collections.Generic;
using System.Linq;
using xCommons.Extensions;
using xExceptions.Constants;

namespace xIdentityHelper.Extensions
{
    public static class XUserRoleExtensions
    {
        /// <summary>
        /// Converts an String to XUserRole ...
        /// </summary>
        /// <param name="role"></param>
        /// <returns></returns>
        public static XUserRole ToXUserRole(this string role)
        {
            //
            var result = XUserRole.User;

            //
            // Validate ...
            if (role.IsNullOrEmpty())
            {
                XException.InvalidArgs.Throw();
            }

            //
            var roles = new List<string>
            {
                role
            };
            result = roles.GetTopRole();

            //
            return result;
        }

        /// <summary>
        /// Retrieve User Top Role based on Role Lists ... 
        /// </summary>
        /// <param name="roles"></param>
        /// <returns></returns>
        public static XUserRole GetTopRole(this IEnumerable<string> roles)
        {
            //
            // Validate ...
            if (roles.IsNull() || !roles.HasChild())
            {
                XException.InvalidArgs.Throw();
            }

            //
            // Normalize Roles ...
            roles = roles.Select(r => r.ToNormalString());

            //
            var result = XUserRole.User;

            //
            // Admin ...
            if (roles.Contains(XUserRole.Admin.GetStringValue().ToNormalString()))
            {
                result = XUserRole.Admin;
            }
            //
            // ResponsibleManager ...
            else if (roles.Contains(XUserRole.ResponsibleManager.GetStringValue().ToNormalString()))
            {
                result = XUserRole.ResponsibleManager;
            }
            //
            // Journalist ...
            else if (roles.Contains(XUserRole.Journalist.GetStringValue().ToNormalString()))
            {
                result = XUserRole.Journalist;
            }
            //
            // ChiefClerk ...
            else if (roles.Contains(XUserRole.ChiefClerk.GetStringValue().ToNormalString()))
            {
                result = XUserRole.ChiefClerk;
            }
            //
            // ChiefClerkAssistant ...
            else if (roles.Contains(XUserRole.ChiefClerkAssistant.GetStringValue().ToNormalString()))
            {
                result = XUserRole.ChiefClerkAssistant;
            }
            //
            // Actuary ...
            else if (roles.Contains(XUserRole.Actuary.GetStringValue().ToNormalString()))
            {
                result = XUserRole.Actuary;
            }
            //
            // ActuaryAssistant ...
            else if (roles.Contains(XUserRole.ActuaryAssistant.GetStringValue().ToNormalString()))
            {
                result = XUserRole.ActuaryAssistant;
            }
            //
            // Reporter ...
            else if (roles.Contains(XUserRole.Reporter.GetStringValue().ToNormalString()))
            {
                result = XUserRole.Reporter;
            }
            //
            // ReporterAssistant ...
            else if (roles.Contains(XUserRole.ReporterAssistant.GetStringValue().ToNormalString()))
            {
                result = XUserRole.ReporterAssistant;
            }
            //
            // Agent ...
            else if (roles.Contains(XUserRole.Agent.GetStringValue().ToNormalString()))
            {
                result = XUserRole.Agent;
            }
            //
            // User ...
            else if (roles.Contains(XUserRole.User.GetStringValue().ToNormalString()))
            {
                result = XUserRole.User;
            }
            else
            {
                XException.InvalidData.Throw();
            }

            //
            return result;
        }

        /// <summary>
        /// Check User Roles has Specified Permissions or not ...
        /// </summary>
        /// <param name="roles"></param>
        /// <param name="role"></param>
        /// <returns></returns>
        public static bool HasRolePermissions(this IEnumerable<string> roles, XUserRole role)
        {
            //
            // Validate ...
            var result =
                !roles.IsNull() &&
                roles.HasChild();
            if (!result)
            {
                return result;
            }

            //
            try
            {
                //
                var topRole = roles.GetTopRole();

                //
                result = (int)topRole >= (int)role;
            }
            catch
            {
                result = false;
            }

            //
            return result;
        }
        public static bool HasRolePermissions(this IEnumerable<string> roles, string role)
        {
            //
            // Validate ...
            var result =
                !roles.IsNull() &&
                roles.HasChild() &&
                !role.IsNullOrEmpty();
            if (!result)
            {
                return result;
            }

            //
            var roleEnum = role.ToXUserRole();
            result = roles.HasRolePermissions(roleEnum);

            //
            return result;
        }
    }
}