using Fitness_core_BE.DTOs.Ledger;
using Fitness_core_BE.Interfaces;
using Fitness_core_BE.Models;
using Microsoft.EntityFrameworkCore;

namespace Fitness_core_BE.Repos
{
    public class ProfitLossRepository : IProfitLossRepository
    {
        // Every method here is already scoped to a single caller-owned clientId (resolved
        // from the ambient tenant), so no cross-tenant fan-out is needed. PaymentTransactions
        // (member-payment rows), StaffPayments and LedgerEntries are tenant-bucket;
        // ClientInvoices (platform billing) is central.
        private readonly TenantDbContext _context;
        private readonly CentralDbContext _central;

        public ProfitLossRepository(TenantDbContext context, CentralDbContext central)
        {
            _context = context;
            _central = central;
        }

        public async Task<List<LedgerEntryDto>> GetDerivedEntriesAsync(
            Guid clientId,
            DateTime fromUtc,
            DateTime toUtc,
            CancellationToken ct = default)
        {
            var memberPayments = await _context.PaymentTransactions
                .AsNoTracking()
                .Where(payment =>
                    payment.FK_ClientId == clientId &&
                    payment.FK_CustomerInvoiceId != null &&
                    payment.IsApproved == true &&
                    payment.IsActive == true &&
                    payment.PayDate != null &&
                    payment.PayDate >= fromUtc &&
                    payment.PayDate < toUtc)
                .Select(payment => new LedgerEntryDto
                {
                    EntryType = "Income",
                    Category = "Member Payments",
                    Description = payment.PayNote,
                    Amount = payment.PayAmount,
                    EntryDate = payment.PayDate!.Value,
                    IsManual = false
                })
                .ToListAsync(ct);

            var platformInvoices = await _central.ClientInvoices
                .AsNoTracking()
                .Where(invoice =>
                    invoice.ClientSubscription.FKClientId == clientId &&
                    invoice.PaidAmount > 0 &&
                    invoice.ClientInvoiceDate >= fromUtc &&
                    invoice.ClientInvoiceDate < toUtc)
                .Select(invoice => new LedgerEntryDto
                {
                    EntryType = "Expense",
                    Category = "Platform Fees",
                    Description = "HexaFitness platform invoice",
                    Amount = invoice.PaidAmount,
                    EntryDate = invoice.ClientInvoiceDate,
                    IsManual = false
                })
                .ToListAsync(ct);

            var staffPayments = await _context.StaffPayments
                .AsNoTracking()
                .Where(payment =>
                    payment.Staff.FKClientId == clientId &&
                    payment.PaidAt >= fromUtc &&
                    payment.PaidAt < toUtc)
                .Select(payment => new LedgerEntryDto
                {
                    EntryType = "Expense",
                    Category = "Staff Payroll",
                    Description = payment.Note,
                    Amount = payment.Amount,
                    EntryDate = payment.PaidAt,
                    IsManual = false
                })
                .ToListAsync(ct);

            memberPayments.AddRange(platformInvoices);
            memberPayments.AddRange(staffPayments);
            return memberPayments;
        }

        public Task<List<LedgerEntry>> GetManualEntriesAsync(
            Guid clientId,
            DateTime fromUtc,
            DateTime toUtc,
            CancellationToken ct = default)
        {
            return _context.LedgerEntries
                .AsNoTracking()
                .Where(entry =>
                    entry.FKClientId == clientId &&
                    entry.EntryDate >= fromUtc &&
                    entry.EntryDate < toUtc)
                .ToListAsync(ct);
        }

        public Task<LedgerEntry?> GetManualEntryByIdAsync(
            Guid id,
            CancellationToken ct = default)
        {
            return _context.LedgerEntries.FirstOrDefaultAsync(entry => entry.Id == id, ct);
        }

        public async Task AddManualEntryAsync(
            LedgerEntry entry,
            CancellationToken ct = default)
        {
            await _context.LedgerEntries.AddAsync(entry, ct);
        }

        public void RemoveManualEntry(LedgerEntry entry)
        {
            _context.LedgerEntries.Remove(entry);
        }
    }
}