using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authorization;
using Microsoft.EntityFrameworkCore;
using Sozsoft.Notifications.Domain;
using Sozsoft.Notifications.Entities;
using Volo.Abp.Application.Dtos;
using Volo.Abp.Application.Services;
using Volo.Abp.Domain.Entities;
using Volo.Abp.Domain.Repositories;
using Volo.Abp.Identity;

namespace Sozsoft.Notifications.NotificationRules;

[Authorize]
public class NotificationRuleAppService : CrudAppService<
    NotificationRule,
    NotificationRuleDto,
    Guid,
    PagedAndSortedResultRequestDto,
    CreateUpdateNotificationRuleDto>,
    INotificationRuleAppService
{
    private readonly IIdentityUserRepository repositoryUser;

    public NotificationRuleAppService(
        IRepository<NotificationRule, Guid> repository,
        IIdentityUserRepository repositoryUser
    ) : base(repository)
    {
        this.repositoryUser = repositoryUser;
    }

    /// <summary>
    /// Birimin kendi kodu ve tum ust birim kodlari. Ust birime tanimlanan kural alt birimlere de
    /// isledigi icin (<c>NotificationManager</c> birimi cocuklariyla birlikte cozer) kullanicinin
    /// gorecegi kurallar bu zincirin tamamindan gelir.
    /// </summary>
    private static void AddUnitCodeWithParents(string? code, List<string> codes)
    {
        while (!code.IsNullOrWhiteSpace())
        {
            codes.Add(code!);
            code = OrganizationUnit.GetParentCode(code!);
        }
    }

    protected override async Task<IQueryable<NotificationRule>> CreateFilteredQueryAsync(PagedAndSortedResultRequestDto input)
    {
        // Bir kullanıcının ait olduğu organization unit'lerin her bir parentının kodu lazım
        // Böylece bir kullanıcının üst birimleri de dahil alabileceği tüm bildirim tiplerini listeleyebileceğiz
        var organizationUnits = await repositoryUser.GetOrganizationUnitsAsync(CurrentUser.Id!.Value);
        var ouCodes = new List<string>();
        foreach (var unit in organizationUnits)
        {
            AddUnitCodeWithParents(unit.Code, ouCodes); //01.02.03 -> 01.02.03, 01.02, 01
        }
        ouCodes = [.. ouCodes.Distinct()];

        var query = await base.CreateFilteredQueryAsync(input);
        return query.Where(a =>
            a.RecipientType == NotificationRecipientTypes.User && a.RecipientId == CurrentUser.UserName ||
            a.RecipientType == NotificationRecipientTypes.Role && CurrentUser.Roles.Contains(a.RecipientId) ||
            a.RecipientType == NotificationRecipientTypes.OrganizationUnit && a.RecipientId != null && ouCodes.Contains(a.RecipientId) ||
            a.RecipientType == NotificationRecipientTypes.All);
    }

    public async Task<List<NotificationTypeDto>> GetMyNotificationTypesAsync()
    {
        var query = await CreateFilteredQueryAsync(new PagedAndSortedResultRequestDto());

        return await query
            .Select(a => new NotificationTypeDto
            {
                Id = a.NotificationTypeId,
                Name = a.NotificationType.Name,
                Description = a.NotificationType.Description
            })
            .Distinct()
            .OrderBy(a => a.Name)
            .ToListAsync();
    }

    public async Task<NotificationRuleSummaryDto> GetRuleSummaryAsync(Guid ruleId)
    {
        var query = await Repository.GetQueryableAsync();

        return await query
            .Where(rule => rule.Id == ruleId)
            .Select(rule => new NotificationRuleSummaryDto
            {
                Id = rule.Id,
                NotificationTypeName = rule.NotificationType.Name,
                Channel = rule.Channel,
                RecipientType = rule.RecipientType,
                RecipientId = rule.RecipientId,
                IsActive = rule.IsActive
            })
            .FirstOrDefaultAsync()
            ?? throw new EntityNotFoundException(typeof(NotificationRule), ruleId);
    }

    public async Task<List<NotificationRuleDto>> GetMyNotificationRules()
    {
        var query = await CreateFilteredQueryAsync(new PagedAndSortedResultRequestDto());
        var all = await query.ToListAsync();
        var list = all
            .GroupBy(a => new { a.NotificationTypeId, a.Channel })
            .Select(a =>
            {
                var item = a.FirstOrDefault(a => a.IsFixed)
                        ?? a.FirstOrDefault(a => a.IsCustomized)
                        ?? a.FirstOrDefault(a => a.IsActive)
                        ?? a.First();
                return new NotificationRuleDto
                {
                    Id = item.Id,
                    NotificationTypeId = a.Key.NotificationTypeId,
                    Channel = a.Key.Channel,
                    IsActive = item.IsActive,
                    IsFixed = item.IsFixed,
                    IsCustomized = item.IsCustomized,
                };
            })
            .ToList();

        return list;
    }

    public async Task PostMyNotificationRule(CreateUpdateNotificationRuleDto Input)
    {
        var query = await CreateFilteredQueryAsync(new PagedAndSortedResultRequestDto());
        var item = await query.FirstOrDefaultAsync(a =>
            a.RecipientType == NotificationRecipientTypes.User &&
            a.RecipientId == CurrentUser.UserName &&
            a.IsCustomized &&
            a.Channel == Input.Channel &&
            a.NotificationTypeId == Input.NotificationTypeId);
        if (item is null)
        {
            // insert
            item = new NotificationRule
            {
                NotificationTypeId = Input.NotificationTypeId,
                RecipientType = NotificationRecipientTypes.User,
                RecipientId = CurrentUser.UserName,
                Channel = Input.Channel,
                IsActive = Input.IsActive,
                IsFixed = false,
                IsCustomized = true
            };
            await Repository.InsertAsync(item);
        }
        else
        {
            item.IsActive = Input.IsActive;
            await Repository.UpdateAsync(item);
        }
    }

    public async Task DeleteMyNotificationRules(Guid NotificationTypeId)
    {
        var query = await CreateFilteredQueryAsync(new PagedAndSortedResultRequestDto());
        var items = await query.Where(a =>
            a.RecipientType == NotificationRecipientTypes.User &&
            a.RecipientId == CurrentUser.UserName &&
            a.IsCustomized &&
            a.NotificationTypeId == NotificationTypeId)
            .ToListAsync();

        await Repository.DeleteManyAsync(items);
    }
}