using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using Umbraco.Core;
using Umbraco.Core.Cache;
using Umbraco.Core.Configuration;
using Umbraco.Core.IO;
using Umbraco.Core.Mapping;
using Umbraco.Core.Models.Membership;
using Umbraco.Web.Models.ContentEditing;
using Umbraco.Core.Models;
using Umbraco.Core.Models.Entities;
using Umbraco.Core.Models.Sections;
using Umbraco.Core.Services;
using Umbraco.Core.Strings;
using Umbraco.Web.Actions;
using Umbraco.Web.Services;
using Umbraco.Core.Media;

namespace Umbraco.Web.Models.Mapping
{
    public class UserMapDefinition : IMapDefinition
    {
        private readonly ISectionService _sectionService;
        private readonly IEntityService _entityService;
        private readonly IUserService _userService;
        private readonly ILocalizedTextService _textService;
        private readonly ActionCollection _actions;
        private readonly AppCaches _appCaches;
        private readonly IGlobalSettings _globalSettings;
        private readonly IMediaFileSystem _mediaFileSystem;
        private readonly IShortStringHelper _shortStringHelper;
        private readonly IImageUrlGenerator _imageUrlGenerator;

        public UserMapDefinition(ILocalizedTextService textService, IUserService userService, IEntityService entityService, ISectionService sectionService,
            AppCaches appCaches, ActionCollection actions, IGlobalSettings globalSettings, IMediaFileSystem mediaFileSystem, IShortStringHelper shortStringHelper,
            IImageUrlGenerator imageUrlGenerator)
        {
            _sectionService = sectionService;
            _entityService = entityService;
            _userService = userService;
            _textService = textService;
            _actions = actions;
            _appCaches = appCaches;
            _globalSettings = globalSettings;
            _mediaFileSystem = mediaFileSystem;
            _shortStringHelper = shortStringHelper;
            _imageUrlGenerator = imageUrlGenerator;
        }

        public void DefineMaps(UmbracoMapper mapper)
        {
            mapper.Define<UserGroupSave, IUserGroup>((source, context) => new UserGroup(_shortStringHelper) { CreateDate = DateTime.UtcNow }, Map);
            mapper.Define<UserInvite, IUser>(Map);
            mapper.Define<IProfile, ContentEditing.UserProfile>((source, context) => new ContentEditing.UserProfile(), Map);
            mapper.Define<IReadOnlyUserGroup, UserGroupBasic>((source, context) => new UserGroupBasic(), Map);
            mapper.Define<IUserGroup, UserGroupBasic>((source, context) => new UserGroupBasic(), Map);
            mapper.Define<IUserGroup, AssignedUserGroupPermissions>((source, context) => new AssignedUserGroupPermissions(), Map);
            mapper.Define<EntitySlim, AssignedContentPermissions>((source, context) => new AssignedContentPermissions(), Map);
            mapper.Define<IUserGroup, UserGroupDisplay>((source, context) => new UserGroupDisplay(), Map);
            mapper.Define<IUser, UserBasic>((source, context) => new UserBasic(), Map);
            mapper.Define<IUser, UserDetail>((source, context) => new UserDetail(), Map);

            // used for merging existing UserSave to an existing IUser instance - this will not create an IUser instance!
            mapper.Define<UserSave, IUser>(Map);

            // important! Currently we are never mapping to multiple UserDisplay objects but if we start doing that
            // this will cause an N+1 and we'll need to change how this works.
            mapper.Define<IUser, UserDisplay>((source, context) => new UserDisplay(), Map);
        }

        // mappers

        private static void Map(UserGroupSave source, IUserGroup target, MapperContext context)
        {
            if (!(target is UserGroup ttarget))
                throw new NotSupportedException($"{nameof(target)} must be a UserGroup.");
            Map(source, ttarget);
        }

        // Umbraco.Code.MapAll -CreateDate -UpdateDate -DeleteDate
        private static void Map(UserGroupSave source, UserGroup target)
        {
            target.StartMediaId = source.StartMediaId;
            target.StartContentId = source.StartContentId;
            target.Icon = source.Icon;
            target.Alias = source.Alias;
            target.Name = source.Name;
            target.Permissions = source.DefaultPermissions;
            target.Key = source.Key;

            var id = GetIntId(source.Id);
            if (id > 0)
                target.Id = id;

            target.ClearAllowedSections();
            foreach (var section in source.Sections)
                target.AddAllowedSection(section);
        }

        // Umbraco.Code.MapAll -CreateDate -UpdateDate -DeleteDate
        // Umbraco.Code.MapAll -Id -TourData -StartContentIds -StartMediaIds -Language -Username
        // Umbraco.Code.MapAll -PasswordQuestion -SessionTimeout -EmailConfirmedDate -InvitedDate
        // Umbraco.Code.MapAll -SecurityStamp -Avatar -ProviderUserKey -RawPasswordValue
        // Umbraco.Code.MapAll -RawPasswordAnswerValue -Comments -IsApproved -IsLockedOut -LastLoginDate
        // Umbraco.Code.MapAll -LastPasswordChangeDate -LastLockoutDate -FailedPasswordAttempts
        private void Map(UserInvite source, IUser target, MapperContext context)
        {
            target.Email = source.Email;
            target.Key = source.Key;
            target.Name = source.Name;
            target.IsApproved = false;

            target.ClearGroups();
            var groups = _userService.GetUserGroupsByAlias(source.UserGroups.ToArray());
            foreach (var group in groups)
                target.AddGroup(group.ToReadOnlyGroup());
        }

        // Umbraco.Code.MapAll -CreateDate -UpdateDate -DeleteDate
        // Umbraco.Code.MapAll -TourData -SessionTimeout -EmailConfirmedDate -InvitedDate -SecurityStamp -Avatar
        // Umbraco.Code.MapAll -ProviderUserKey -RawPasswordValue -RawPasswordAnswerValue -PasswordQuestion -Comments
        // Umbraco.Code.MapAll -IsApproved -IsLockedOut -LastLoginDate -LastPasswordChangeDate -LastLockoutDate
        // Umbraco.Code.MapAll -FailedPasswordAttempts
        private void Map(UserSave source, IUser target, MapperContext context)
        {
            target.Name = source.Name;
            target.StartContentIds = source.StartContentIds ?? Array.Empty<int>();
            target.StartMediaIds = source.StartMediaIds ?? Array.Empty<int>();
            target.Language = source.Culture;
            target.Email = source.Email;
            target.Key = source.Key;
            target.Username = source.Username;
            target.Id = source.Id;

            target.ClearGroups();
            var groups = _userService.GetUserGroupsByAlias(source.UserGroups.ToArray());
            foreach (var group in groups)
                target.AddGroup(group.ToReadOnlyGroup());
        }

        // Umbraco.Code.MapAll
        private static void Map(IProfile source, ContentEditing.UserProfile target, MapperContext context)
        {
            target.Name = source.Name;
            target.UserId = source.Id;
        }

        // Umbraco.Code.MapAll -ContentStartNode -UserCount -MediaStartNode -Key -Sections
        // Umbraco.Code.MapAll -Notifications -Udi -Trashed -AdditionalData -IsSystemUserGroup
        private void Map(IReadOnlyUserGroup source, UserGroupBasic target, MapperContext context)
        {
            target.Alias = source.Alias;
            target.Icon = source.Icon;
            target.Id = source.Id;
            target.Name = source.Name;
            target.ParentId = -1;
            target.Path = "-1," + source.Id;
            target.IsSystemUserGroup = source.IsSystemUserGroup();

            MapUserGroupBasic(target, source.AllowedSections, source.StartContentId, source.StartMediaId, context);
        }

        // Umbraco.Code.MapAll -ContentStartNode -MediaStartNode -Sections -Notifications
        // Umbraco.Code.MapAll -Udi -Trashed -AdditionalData -IsSystemUserGroup
        private void Map(IUserGroup source, UserGroupBasic target, MapperContext context)
        {
            target.Alias = source.Alias;
            target.Icon = source.Icon;
            target.Id = source.Id;
            target.Key = source.Key;
            target.Name = source.Name;
            target.ParentId = -1;
            target.Path = "-1," + source.Id;
            target.UserCount = source.UserCount;
            target.IsSystemUserGroup = source.IsSystemUserGroup();

            MapUserGroupBasic(target, source.AllowedSections, source.StartContentId, source.StartMediaId, context);
        }

        // Umbraco.Code.MapAll -Udi -Trashed -AdditionalData -AssignedPermissions
        private void Map(IUserGroup source, AssignedUserGroupPermissions target, MapperContext context)
        {
            target.Id = source.Id;
            target.Alias = source.Alias;
            target.Icon = source.Icon;
            target.Key = source.Key;
            target.Name = source.Name;
            target.ParentId = -1;
            target.Path = "-1," + source.Id;

            target.DefaultPermissions = MapUserGroupDefaultPermissions(source);

            if (target.Icon.IsNullOrWhiteSpace())
                target.Icon = Constants.Icons.UserGroup;
        }

        // Umbraco.Code.MapAll -Trashed -Alias -AssignedPermissions
        private static void Map(EntitySlim source, AssignedContentPermissions target, MapperContext context)
        {
            target.Icon = MapContentTypeIcon(source);
            target.Id = source.Id;
            target.Key = source.Key;
            target.Name = source.Name;
            target.ParentId = source.ParentId;
            target.Path = source.Path;
            target.Udi = Udi.Create(ObjectTypes.GetUdiType(source.NodeObjectType), source.Key);

            if (source.NodeObjectType == Constants.ObjectTypes.Member && target.Icon.IsNullOrWhiteSpace())
                target.Icon = Constants.Icons.Member;
        }

        // Umbraco.Code.MapAll -ContentStartNode -MediaStartNode -Sections -Notifications -Udi
        // Umbraco.Code.MapAll -Trashed -AdditionalData -Users -AssignedPermissions
        private void Map(IUserGroup source, UserGroupDisplay target, MapperContext context)
        {
            target.Alias = source.Alias;
            target.DefaultPermissions = MapUserGroupDefaultPermissions(source);
            target.Icon = source.Icon;
            target.Id = source.Id;
            target.Key = source.Key;
            target.Name = source.Name;
            target.ParentId = -1;
            target.Path = "-1," + source.Id;
            target.UserCount = source.UserCount;
            target.IsSystemUserGroup = source.IsSystemUserGroup();

            MapUserGroupBasic(target, source.AllowedSections, source.StartContentId, source.StartMediaId, context);

            //Important! Currently we are never mapping to multiple UserGroupDisplay objects but if we start doing that
            // this will cause an N+1 and we'll need to change how this works.
            var users = _userService.GetAllInGroup(source.Id);
            target.Users = context.MapEnumerable<IUser, UserBasic>(users);

            //Deal with assigned permissions:

            var allContentPermissions = _userService.GetPermissions(source, true)
                .ToDictionary(x => x.EntityId, x => x);

            IEntitySlim[] contentEntities;
            if (allContentPermissions.Keys.Count == 0)
            {
                contentEntities = Array.Empty<IEntitySlim>();
            }
            else
            {
                // a group can end up with way more than 2000 assigned permissions,
                // so we need to break them into groups in order to avoid breaking
                // the entity service due to too many Sql parameters.

                var list = new List<IEntitySlim>();
                foreach (var idGroup in allContentPermissions.Keys.InGroupsOf(2000))
                    list.AddRange(_entityService.GetAll(UmbracoObjectTypes.Document, idGroup.ToArray()));
                contentEntities = list.ToArray();
            }

            var allAssignedPermissions = new List<AssignedContentPermissions>();
            foreach (var entity in contentEntities)
            {
                var contentPermissions = allContentPermissions[entity.Id];

                var assignedContentPermissions = context.Map<AssignedContentPermissions>(entity);
                assignedContentPermissions.AssignedPermissions = AssignedUserGroupPermissions.ClonePermissions(target.DefaultPermissions);

                //since there is custom permissions assigned to this node for this group, we need to clear all of the default permissions
                //and we'll re-check it if it's one of the explicitly assigned ones
                foreach (var permission in assignedContentPermissions.AssignedPermissions.SelectMany(x => x.Value))
                {
                    permission.Checked = false;
                    permission.Checked = contentPermissions.AssignedPermissions.Contains(permission.PermissionCode, StringComparer.InvariantCulture);
                }

                allAssignedPermissions.Add(assignedContentPermissions);
            }

            target.AssignedPermissions = allAssignedPermissions;
        }

        // Umbraco.Code.MapAll -Notifications -Udi -Icon -IsCurrentUser -Trashed -ResetPasswordValue
        // Umbraco.Code.MapAll -Alias -AdditionalData
        private void Map(IUser source, UserDisplay target, MapperContext context)
        {
            target.AvailableCultures = _textService.GetSupportedCultures().ToDictionary(x => x.Name, x => x.DisplayName);
            target.Avatars = source.GetUserAvatarUrls(_appCaches.RuntimeCache, _mediaFileSystem, _imageUrlGenerator);
            target.CalculatedStartContentIds = GetStartNodes(source.CalculateContentStartNodeIds(_entityService), UmbracoObjectTypes.Document, "content/contentRoot", context);
            target.CalculatedStartMediaIds = GetStartNodes(source.CalculateMediaStartNodeIds(_entityService), UmbracoObjectTypes.Media, "media/mediaRoot", context);
            target.CreateDate = source.CreateDate;
            target.Culture = source.GetUserCulture(_textService, _globalSettings).ToString();
            target.Email = source.Email;
            target.EmailHash = source.Email.ToLowerInvariant().Trim().GenerateHash();
            target.FailedPasswordAttempts = source.FailedPasswordAttempts;
            target.Id = source.Id;
            target.Key = source.Key;
            target.LastLockoutDate = source.LastLockoutDate;
            target.LastLoginDate = source.LastLoginDate == default ? null : (DateTime?) source.LastLoginDate;
            target.LastPasswordChangeDate = source.LastPasswordChangeDate;
            target.Name = source.Name;
            target.Navigation = CreateUserEditorNavigation();
            target.ParentId = -1;
            target.Path = "-1," + source.Id;
            target.StartContentIds = GetStartNodes(source.StartContentIds.ToArray(), UmbracoObjectTypes.Document, "content/contentRoot", context);
            target.StartMediaIds = GetStartNodes(source.StartMediaIds.ToArray(), UmbracoObjectTypes.Media, "media/mediaRoot", context);
            target.UpdateDate = source.UpdateDate;
            target.UserGroups = context.MapEnumerable<IReadOnlyUserGroup, UserGroupBasic>(source.Groups);
            target.Username = source.Username;
            target.UserState = source.UserState;
        }

        // Umbraco.Code.MapAll -Notifications -IsCurrentUser -Udi -Icon -Trashed -Alias -AdditionalData
        private void Map(IUser source, UserBasic target, MapperContext context)
        {
            //Loading in the user avatar's requires an external request if they don't have a local file avatar, this means that initial load of paging may incur a cost
            //Alternatively, if this is annoying the back office UI would need to be updated to request the avatars for the list of users separately so it doesn't look
            //like the load time is waiting.
            target.Avatars = source.GetUserAvatarUrls(_appCaches.RuntimeCache, _mediaFileSystem, _imageUrlGenerator);
            target.Culture = source.GetUserCulture(_textService, _globalSettings).ToString();
            target.Email = source.Email;
            target.EmailHash = source.Email.ToLowerInvariant().Trim().GenerateHash();
            target.Id = source.Id;
            target.Key = source.Key;
            target.LastLoginDate = source.LastLoginDate == default ? null : (DateTime?) source.LastLoginDate;
            target.Name = source.Name;
            target.ParentId = -1;
            target.Path = "-1," + source.Id;
            target.UserGroups = context.MapEnumerable<IReadOnlyUserGroup, UserGroupBasic>(source.Groups);
            target.Username = source.Username;
            target.UserState = source.UserState;
        }

        // Umbraco.Code.MapAll -SecondsUntilTimeout
        private void Map(IUser source, UserDetail target, MapperContext context)
        {
            target.AllowedSections = source.AllowedSections;
            target.Avatars = source.GetUserAvatarUrls(_appCaches.RuntimeCache, _mediaFileSystem, _imageUrlGenerator);
            target.Culture = source.GetUserCulture(_textService, _globalSettings).ToString();
            target.Email = source.Email;
            target.EmailHash = source.Email.ToLowerInvariant().Trim().GenerateHash();
            target.Name = source.Name;
            target.StartContentIds = source.CalculateContentStartNodeIds(_entityService);
            target.StartMediaIds = source.CalculateMediaStartNodeIds(_entityService);
            target.UserId = source.Id;

            //we need to map the legacy UserType
            //the best we can do here is to return the user's first user group as a IUserType object
            //but we should attempt to return any group that is the built in ones first
            target.UserGroups = source.Groups.Select(x => x.Alias).ToArray();
        }

        // helpers

        private void MapUserGroupBasic(UserGroupBasic target, IEnumerable<string> sourceAllowedSections, int? sourceStartContentId, int? sourceStartMediaId, MapperContext context)
        {
            var allSections = _sectionService.GetSections();
            target.Sections = context.MapEnumerable<ISection, Section>(allSections.Where(x => sourceAllowedSections.Contains(x.Alias)));

            if (sourceStartMediaId > 0)
                target.MediaStartNode = context.Map<EntityBasic>(_entityService.Get(sourceStartMediaId.Value, UmbracoObjectTypes.Media));
            else if (sourceStartMediaId == -1)
                target.MediaStartNode = CreateRootNode(_textService.Localize("media/mediaRoot"));

            if (sourceStartContentId > 0)
                target.ContentStartNode = context.Map<EntityBasic>(_entityService.Get(sourceStartContentId.Value, UmbracoObjectTypes.Document));
            else if (sourceStartContentId == -1)
                target.ContentStartNode = CreateRootNode(_textService.Localize("content/contentRoot"));

            if (target.Icon.IsNullOrWhiteSpace())
                target.Icon = Constants.Icons.UserGroup;
        }

        private IDictionary<string, IEnumerable<Permission>> MapUserGroupDefaultPermissions(IUserGroup source)
        {
            Permission GetPermission(IAction action)
                => new Permission
                {
                    Category = action.Category.IsNullOrWhiteSpace()
                        ? _textService.Localize($"actionCategories/{Constants.Conventions.PermissionCategories.OtherCategory}")
                        : _textService.Localize($"actionCategories/{action.Category}"),
                    Name = _textService.Localize($"actions/{action.Alias}"),
                    Description = _textService.Localize($"actionDescriptions/{action.Alias}"),
                    Icon = action.Icon,
                    Checked = source.Permissions != null && source.Permissions.Contains(action.Letter.ToString(CultureInfo.InvariantCulture)),
                    PermissionCode = action.Letter.ToString(CultureInfo.InvariantCulture)
                };

            return _actions
                .Where(x => x.CanBePermissionAssigned)
                .Select(GetPermission)
                .GroupBy(x => x.Category)
                .ToDictionary(x => x.Key, x => (IEnumerable<Permission>)x.ToArray());
        }

        private static string MapContentTypeIcon(IEntitySlim entity)
            => entity is IContentEntitySlim contentEntity ? contentEntity.ContentTypeIcon : null;

        private IEnumerable<EntityBasic> GetStartNodes(int[] startNodeIds, UmbracoObjectTypes objectType, string localizedKey, MapperContext context)
        {
            if (startNodeIds.Length <= 0)
                return Enumerable.Empty<EntityBasic>();

            var startNodes = new List<EntityBasic>();
            if (startNodeIds.Contains(-1))
                startNodes.Add(CreateRootNode(_textService.Localize(localizedKey)));

            var mediaItems = _entityService.GetAll(objectType, startNodeIds);
            startNodes.AddRange(context.MapEnumerable<IEntitySlim, EntityBasic>(mediaItems));
            return startNodes;
        }

        private IEnumerable<EditorNavigation> CreateUserEditorNavigation()
        {
            return new[]
            {
                new EditorNavigation
                {
                    Active = true,
                    Alias = "details",
                    Icon = "icon-umb-users",
                    Name = _textService.Localize("general/user"),
                    View = "views/users/views/user/details.html"
                }
            };
        }

        private static int GetIntId(object id)
        {
            var result = id.TryConvertTo<int>();
            if (result.Success == false)
            {
                throw new InvalidOperationException(
                    "Cannot convert the profile to a " + typeof(UserDetail).Name + " object since the id is not an integer");
            }
            return result.Result;
        }

        private EntityBasic CreateRootNode(string name)
        {
            return new EntityBasic
            {
                Name = name,
                Path = "-1",
                Icon = "icon-folder",
                Id = -1,
                Trashed = false,
                ParentId = -1
            };
        }
    }
}