using MagicCarpetContracts.Enums;
using MagicCarpetContracts.Exceptions;
using MagicCarpetContracts.Extensions;
using MagicCarpetContracts.Infrastructure;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MagicCarpetContracts.DataModels;

public class SaleDataModel : IValidation
{
    private readonly ClientDataModel? _client;

    private readonly EmployeeDataModel? _employee;

    public string Id { get; private set; }

    public string EmployeeId { get; private set; }

    public string? ClientId { get; private set; }

    public DateTime SaleDate { get; private set; } = DateTime.UtcNow;

    public double Sum { get; private set; }

    public DiscountType DiscountType { get; private set; }

    public double Discount { get; private set; }

    public bool IsCancel { get; private set; }

    public List<SaleTourDataModel>? Tours { get; private set; }

    public string ClientFIO => _client?.FIO ?? string.Empty;

    public string EmployeeFIO => _employee?.FIO ?? string.Empty;

    public SaleDataModel(string id, string employeeId, string? clientId, DiscountType discountType, bool isCancel, List<SaleTourDataModel> saleTours)
    {
        Id = id;
        EmployeeId = employeeId;
        ClientId = clientId;
        DiscountType = discountType;
        IsCancel = isCancel;
        Tours = saleTours;
        var percent = 0.0;
        foreach (DiscountType elem in Enum.GetValues<DiscountType>())
        {
            if ((elem & discountType) != 0)
            {
                switch (elem)
                {
                    case DiscountType.None:
                        break;
                    case DiscountType.OnSale:
                        percent += 0.1;
                        break;
                    case DiscountType.RegularCustomer:
                        percent += 0.5;
                        break;
                    case DiscountType.Certificate:
                        percent += 0.3;
                        break;
                }
            }
        }
        Sum = Tours?.Sum(x => x.Price * x.Count) ?? 0;
        Discount = Sum * percent;
    }

    public SaleDataModel(string id, string employeeId, string? clientId, double sum, DiscountType discountType, double discount, bool isCancel,
        List<SaleTourDataModel> saleTours, EmployeeDataModel employee, ClientDataModel? client) : this(id, employeeId, clientId, discountType, isCancel, saleTours)
    {
        Sum = sum;
        Discount = discount;
        _employee = employee;
        _client = client;
    }

    public SaleDataModel(string id, string employeeId, string? clientId, int discountType, 
        List<SaleTourDataModel> tours) : this(id, employeeId, clientId, (DiscountType)discountType, false, tours) { }

    public void Validate()
    {
        if (Id.IsEmpty())
            throw new ValidationException("Field Id is empty");

        if (!Id.IsGuid())
            throw new ValidationException("The value in the field Id is not a unique identifier");

        if (EmployeeId.IsEmpty())
            throw new ValidationException("Field EmployeeId is empty");

        if (!EmployeeId.IsGuid())
            throw new ValidationException("The value in the field EmployeeId is not a unique identifier");

        if (!ClientId?.IsGuid() ?? !ClientId?.IsEmpty() ?? false)
            throw new ValidationException("The value in the field BuyerId is not a unique identifier");

        if (Sum <= 0)
            throw new ValidationException("Field Sum is less than or equal to 0");

        if ((Tours?.Count ?? 0) == 0)
            throw new ValidationException("The sale must include tours");
    }
}