using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Xml.Serialization;

namespace Schaad.Accounting.Models
{
    public class Transaction
    {
        public string Id { get; set; }
        public string BankTransactionId { get; set; }

        /// <summary>
        /// Needed for booking rule
        /// </summary>
        public string BankTransactionText { get; set; }

        public string RelatedParty { get; set; }

        [Display(Name = "Valuta")]
        [Required]
        public DateTime ValueDate { get; set; }

        [Display(Name = "Buchung")]
        public DateTime BookingDate { get; set; }

        [Display(Name = "Buchungstext")]
        [Required]
        public string Text { get; set; }

        [Display(Name = "Betrag")]
        [Required]
        public decimal Value { get; set; }

        [Display(Name = "Habenkonto")]
        [Required]
        public string OriginAccountId { get; set; }

        [Display(Name = "Sollkonto")]
        [Required]
        public string TargetAccountId { get; set; }

        [Display(Name = "Währungskurs")]
        public decimal? FxRate { get; set; }
        
        [XmlIgnore]
        public bool ReadOnly {get; set;}

        public Transaction()
        {
        }

        public Transaction(BankTransaction bankTransaction, List<Account> accounts)
        {
            BankTransactionId = bankTransaction.Id;
            BankTransactionText = bankTransaction.Text;
            Value = bankTransaction.Value;
            ValueDate = bankTransaction.ValueDate;
            BookingDate = bankTransaction.BookingDate;

            // Depending on positiv or negative value, set the account
            var bankAccount = accounts.FirstOrDefault(a => a.BankAccountNumber == bankTransaction.BankAccountNumber);
            if (Value >= 0)
            {
                TargetAccountId = bankAccount.Id;
                RelatedParty = bankTransaction.Debtor;
            }
            else
            {
                OriginAccountId = bankAccount.Id;
                RelatedParty = bankTransaction.Creditor;
            }
        }

        /// <summary>
        /// Returns a shallow independent copy — used to hand out defensive copies
        /// (e.g. from repository reads) without exposing the caller to later mutation.
        /// </summary>
        public Transaction Clone() => new()
        {
            Id = Id,
            BankTransactionId = BankTransactionId,
            BankTransactionText = BankTransactionText,
            RelatedParty = RelatedParty,
            OriginAccountId = OriginAccountId,
            TargetAccountId = TargetAccountId,
            Text = Text,
            Value = Value,
            ValueDate = ValueDate,
            BookingDate = BookingDate,
            FxRate = FxRate
        };
    }
}