using Fitness_core_BE.Exceptions;
using Fitness_core_BE.Interfaces;
using Fitness_core_BE.Models;
using Microsoft.EntityFrameworkCore;

namespace Fitness_core_BE.Repos
{
    public class AccessDeviceRepo : IAccessDeviceRepo
    {
        private readonly TenantDbContext _dbContext;
        private readonly CentralDbContext _central;

        public AccessDeviceRepo(TenantDbContext dbContext, CentralDbContext central)
        {
            _dbContext = dbContext;
            _central = central;
        }

        public async Task<object> AddDeviceAsync(AccessDevice device)
        {
            var result = await _dbContext.AddAsync(device);
            return result;
        }

        public async Task<AccessDevice> RemoveDeviceAsync(Guid clientId)
        {
            AccessDevice? device = await _dbContext.AccessDevices
                .Where(ad => ad.FKClientId == clientId)
                .FirstOrDefaultAsync();

            if (device == null)
                throw new NotFoundException($"{clientId} don't have a Device in the System");

            device.IsActive = false;

            _dbContext.Update(device);

            return device;

        }

        public async Task<AccessDevice> GetDeviceByDId(Guid deviceId)
        {
            AccessDevice? device = await _dbContext.AccessDevices
                .Where(d => d.DeviceId == deviceId && d.IsActive == true)
                .FirstOrDefaultAsync();

            if (device == null)
                throw new NotFoundException($"{deviceId} is not found");

            return device;
        }

        public Task<AccessDevice?> GetDeviceByIdAsync(
            Guid deviceId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessDevices
                .FirstOrDefaultAsync(device => device.DeviceId == deviceId, ct);
        }

        public Task<AccessDevice?> GetDeviceByHardwareIdAsync(
            Guid clientId,
            string hardwareId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessDevices.FirstOrDefaultAsync(device =>
                device.FKClientId == clientId &&
                device.HardwareId == hardwareId, ct);
        }

        public Task<AccessDevice?> GetActiveDeviceForClientAsync(
            Guid clientId,
            Guid deviceId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessDevices.FirstOrDefaultAsync(device =>
                device.DeviceId == deviceId &&
                device.FKClientId == clientId &&
                device.IsActive, ct);
        }

        public Task<List<AccessDevice>> GetAgentDevicesAsync(
            Guid clientId,
            Guid agentId,
            IReadOnlyCollection<Guid> deviceIds,
            CancellationToken ct = default)
        {
            return _dbContext.AccessDevices
                .Where(device =>
                    device.FKClientId == clientId &&
                    device.FKAgentId == agentId &&
                    deviceIds.Contains(device.DeviceId))
                .ToListAsync(ct);
        }
        public async Task<AccessDevice> GetDeviceByCId(Guid clientId)
        {
            AccessDevice? device = await _dbContext.AccessDevices
                .Where(d => d.FKClientId == clientId && d.IsActive == true)
                .FirstOrDefaultAsync();

            if (device == null)
                throw new NotFoundException($"{clientId} don't have a device in the system");

            return device;
        }

        public async Task<CustomerAccess> AddCustomerAccessAsync(CustomerAccess customerAccess)
        {
            await _dbContext.CustomerAccess.AddAsync(customerAccess);
            return customerAccess;
        }

        public async Task<CustomerAccess> GetByIdAsync(int deviceUserId)
        {
            CustomerAccess? record = await _dbContext.CustomerAccess
                .FindAsync(deviceUserId);

            if (record == null)
                throw new NotFoundException($"{deviceUserId} cannot find in the system");
            return record;
        }
        // Maps a device's employeeNo (== CustomerAccess.Id) back to its CustomerAccess,
        // scoped to the device so the same employeeNo on a different panel can't collide.
        // Returns null (rather than throwing) when there is no mapping for this device user.
        public async Task<CustomerAccess?> GetByDeviceAndUserIdAsync(Guid deviceId, int deviceUserId)
        {
            return await _dbContext.CustomerAccess
                .FirstOrDefaultAsync(c => c.FKDeviceId == deviceId && c.Id == deviceUserId);
        }

        public async Task<CustomerAccess> GetByCusGuidAsync(Guid CusId)
        {
            // No IsActive filter here: this is the lookup WhiteListMember/BlackListMember use
            // to find the record whose IsActive flag they're about to flip. Filtering on
            // IsActive == true made it impossible to ever find (and re-activate) a customer
            // who had already been locked, since locking sets IsActive = false.
            CustomerAccess? record = await _dbContext.CustomerAccess
                .Where(c => c.FKCustomerId == CusId)
                .FirstOrDefaultAsync();

            if (record == null)
                throw new NotFoundException($"record cannot find in the system");
            return record;
        }

        public async Task<CustomerAccess> UpdateAsync(CustomerAccess customerAccess)
        {
            _dbContext.CustomerAccess.Update(customerAccess);
            return customerAccess;
        }

        public async Task<List<AccessDevice>> GetDevicesByClientAsync(Guid clientId)
        {
            return await _dbContext.AccessDevices
                .AsNoTracking()
                .Where(d => d.FKClientId == clientId && d.IsActive == true)
                .ToListAsync();
        }

        public async Task<bool> DeviceBelongsToClientAsync(Guid deviceId, Guid clientId)
        {
            return await _dbContext.AccessDevices
                .AnyAsync(d => d.DeviceId == deviceId && d.FKClientId == clientId);
        }

        public Task<Customer?> GetCustomerByIdAsync(
            Guid customerId,
            CancellationToken ct = default)
        {
            return _central.Customer
                .FirstOrDefaultAsync(customer => customer.CusId == customerId, ct);
        }

        public async Task<Staff?> GetStaffByIdAsync(
            Guid clientId,
            Guid staffId,
            CancellationToken ct = default)
        {
            var staff = await _dbContext.Staff
                .AsNoTracking()
                .FirstOrDefaultAsync(s =>
                    s.StaffId == staffId &&
                    s.FKClientId == clientId, ct);
            if (staff == null)
                return null;

            // Staff.User is central-bucket -- attach it in memory so callers reading
            // staff.User.* still see the right data.
            staff.User = await _central.Users.AsNoTracking().FirstOrDefaultAsync(u => u.UserId == staff.FKUserId, ct);
            return staff;
        }

        // Access on a shared plan is all-or-nothing: the subscription is the unit that was
        // paid for, so locking one person on a couple/group plan has to take their co-members
        // with it, or the locked member simply walks in on their partner's fingerprint.
        public async Task<List<Guid>> GetCoMembersOnSharedSubscriptionsAsync(
            Guid clientId,
            Guid customerId,
            CancellationToken ct = default)
        {
            var sharedSubscriptionIds = await _dbContext.SubscriptionMembers
                .AsNoTracking()
                .Where(member =>
                    member.FKCustomerId == customerId &&
                    member.IsActive &&
                    member.Subscription.IsActive &&
                    member.Subscription.CustomerPlan.FKClientId == clientId &&
                    member.Subscription.CustomerPlan.PlanScope == "Group")
                .Select(member => member.FKSubscriptionId)
                .Distinct()
                .ToListAsync(ct);

            if (sharedSubscriptionIds.Count == 0)
                return new List<Guid>();

            return await _dbContext.SubscriptionMembers
                .AsNoTracking()
                .Where(member =>
                    sharedSubscriptionIds.Contains(member.FKSubscriptionId) &&
                    member.FKCustomerId != customerId &&
                    member.IsActive)
                .Select(member => member.FKCustomerId)
                .Distinct()
                .ToListAsync(ct);
        }

        public Task<bool> IsActiveCustomerMemberAsync(
            Guid clientId,
            Guid customerId,
            CancellationToken ct = default)
        {
            return _dbContext.SubscriptionMembers.AnyAsync(member =>
                member.FKCustomerId == customerId &&
                member.IsActive &&
                member.Subscription.IsActive &&
                member.Subscription.CustomerPlan.FKClientId == clientId, ct);
        }

        public async Task<Guid?> GetLatestActiveClientIdForCustomerAsync(
            Guid customerId,
            CancellationToken ct = default)
        {
            var clientId = await _dbContext.SubscriptionMembers
                .Where(member =>
                    member.FKCustomerId == customerId &&
                    member.IsActive &&
                    member.Subscription.IsActive)
                .OrderByDescending(member => member.Subscription.OnboardDate)
                .Select(member => member.Subscription.CustomerPlan.FKClientId)
                .FirstOrDefaultAsync(ct);
            return clientId == Guid.Empty ? null : clientId;
        }

        public Task<AccessProfile?> GetAccessProfileAsync(
            Guid clientId,
            Guid userId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessProfiles
                .Include(profile => profile.DeviceBindings)
                .FirstOrDefaultAsync(profile =>
                    profile.FKClientId == clientId &&
                    profile.FKUserId == userId, ct);
        }

        public Task<AccessProfile?> GetAccessStatusProfileAsync(
            Guid clientId,
            Guid userId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessProfiles
                .AsNoTracking()
                .Include(profile => profile.DeviceBindings)
                    .ThenInclude(binding => binding.AccessDevice)
                .FirstOrDefaultAsync(profile =>
                    profile.FKClientId == clientId &&
                    profile.FKUserId == userId, ct);
        }

        public Task<List<AccessProfile>> GetAccessProfilesByClientAsync(
            Guid clientId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessProfiles
                .Include(profile => profile.DeviceBindings)
                .Where(profile => profile.FKClientId == clientId)
                .ToListAsync(ct);
        }

        public async Task AddAccessProfileAsync(
            AccessProfile profile,
            CancellationToken ct = default)
        {
            await _dbContext.AccessProfiles.AddAsync(profile, ct);
        }

        public Task<AccessDeviceBinding?> GetBindingAsync(
            long accessProfileId,
            Guid deviceId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessDeviceBindings.FirstOrDefaultAsync(binding =>
                binding.FKAccessProfileId == accessProfileId &&
                binding.FKDeviceId == deviceId, ct);
        }

        public Task<AccessDeviceBinding?> GetBindingByEmployeeNoAsync(
            Guid deviceId,
            string employeeNo,
            CancellationToken ct = default)
        {
            return _dbContext.AccessDeviceBindings
                .Include(binding => binding.AccessProfile)
                .FirstOrDefaultAsync(binding =>
                    binding.FKDeviceId == deviceId &&
                    binding.DeviceEmployeeNo == employeeNo, ct);
        }

        public Task<List<AccessDeviceBinding>> GetBindingsForDeviceAsync(
            Guid deviceId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessDeviceBindings
                .Include(binding => binding.AccessProfile)
                .Where(binding => binding.FKDeviceId == deviceId)
                .ToListAsync(ct);
        }

        public async Task AddBindingAsync(
            AccessDeviceBinding binding,
            CancellationToken ct = default)
        {
            await _dbContext.AccessDeviceBindings.AddAsync(binding, ct);
        }

        public Task<bool> IsDeviceEmployeeNoOccupiedAsync(
            Guid deviceId,
            string employeeNo,
            Guid exceptUserId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessDeviceBindings.AnyAsync(binding =>
                binding.FKDeviceId == deviceId &&
                binding.DeviceEmployeeNo == employeeNo &&
                binding.AccessProfile.FKUserId != exceptUserId, ct);
        }

        public Task<List<UnlinkedDeviceEnrollment>> GetDuplicateUnlinkedEnrollmentsAsync(
            Guid deviceId,
            string employeeNo,
            int deviceUserId,
            CancellationToken ct = default)
        {
            return _dbContext.UnlinkedDeviceEnrollments
                .Where(enrollment =>
                    enrollment.FKDeviceId == deviceId &&
                    enrollment.LinkedAt == null &&
                    (enrollment.DeviceEmployeeNo == employeeNo ||
                     (enrollment.DeviceEmployeeNo == "" &&
                      enrollment.DeviceUserId == deviceUserId)))
                .ToListAsync(ct);
        }

        public Task<UnlinkedDeviceEnrollment?> GetUnlinkedEnrollmentByEmployeeNoAsync(
            Guid deviceId,
            string employeeNo,
            CancellationToken ct = default)
        {
            var tracked = _dbContext.UnlinkedDeviceEnrollments.Local
                .FirstOrDefault(enrollment =>
                    enrollment.FKDeviceId == deviceId &&
                    enrollment.DeviceEmployeeNo == employeeNo &&
                    enrollment.LinkedAt == null);

            return tracked != null
                ? Task.FromResult<UnlinkedDeviceEnrollment?>(tracked)
                : _dbContext.UnlinkedDeviceEnrollments.FirstOrDefaultAsync(enrollment =>
                    enrollment.FKDeviceId == deviceId &&
                    enrollment.DeviceEmployeeNo == employeeNo &&
                    enrollment.LinkedAt == null, ct);
        }

        public async Task AddUnlinkedEnrollmentAsync(
            UnlinkedDeviceEnrollment enrollment,
            CancellationToken ct = default)
        {
            await _dbContext.UnlinkedDeviceEnrollments.AddAsync(enrollment, ct);
        }

        public async Task<Guid?> GetCustomerIdForUserAtClientAsync(
            Guid userId,
            Guid clientId,
            CancellationToken ct = default)
        {
            // Central lookup for the customer identity, then a tenant-scoped membership
            // check -- these used to be a single cross-table query before the split.
            var cusId = await _central.Customer
                .Where(customer => customer.FKUserId == userId)
                .Select(customer => (Guid?)customer.CusId)
                .FirstOrDefaultAsync(ct);
            if (cusId == null)
                return null;

            var belongs = await _dbContext.SubscriptionMembers.AnyAsync(member =>
                member.FKCustomerId == cusId.Value &&
                member.IsActive &&
                member.Subscription.IsActive &&
                member.Subscription.CustomerPlan.FKClientId == clientId, ct);

            return belongs ? cusId : null;
        }

        public Task<bool> IsDeviceCommandableAsync(
            Guid deviceId,
            CancellationToken ct = default)
        {
            return _dbContext.AccessDevices.AnyAsync(device =>
                device.DeviceId == deviceId &&
                device.IsActive &&
                device.FKAgentId != null, ct);
        }

        public async Task UpsertUnlinkedEnrollmentAsync(Guid deviceId, int deviceUserId, string? reportedName)
        {
            // Check already-tracked-but-unsaved entities first: a single attendance-ingest
            // batch can carry several events for the same not-yet-linked device user (e.g.
            // multiple punches since the last sync), and SaveChanges only runs once after the
            // whole batch. A DB-only lookup wouldn't see an earlier Add() in this same batch
            // and would insert a duplicate row per repeated punch.
            var existing = _dbContext.UnlinkedDeviceEnrollments.Local
                .FirstOrDefault(e => e.FKDeviceId == deviceId && e.DeviceUserId == deviceUserId && e.LinkedAt == null)
                ?? await _dbContext.UnlinkedDeviceEnrollments
                    .FirstOrDefaultAsync(e => e.FKDeviceId == deviceId && e.DeviceUserId == deviceUserId && e.LinkedAt == null);

            if (existing != null)
            {
                if (!string.IsNullOrWhiteSpace(reportedName))
                    existing.DeviceReportedName = reportedName;
                return;
            }

            await _dbContext.UnlinkedDeviceEnrollments.AddAsync(new UnlinkedDeviceEnrollment
            {
                Id = Guid.NewGuid(),
                FKDeviceId = deviceId,
                DeviceUserId = deviceUserId,
                DeviceReportedName = reportedName,
                DiscoveredAt = DateTime.UtcNow
            });
        }

        public async Task<List<UnlinkedDeviceEnrollment>> GetUnlinkedEnrollmentsByClientAsync(Guid clientId)
        {
            var enrollments = await _dbContext.UnlinkedDeviceEnrollments
                .AsNoTracking()
                .Include(e => e.AccessDevice)
                .Where(e => e.LinkedAt == null && e.AccessDevice.FKClientId == clientId)
                .OrderByDescending(e => e.DiscoveredAt)
                .ToListAsync();

            // Collapse any duplicate rows already sitting in the table (from before the
            // upsert dedup fix above) so the same physical fingerprint doesn't show up
            // multiple times in the link picker; keep the most recently discovered one.
            return enrollments
                .GroupBy(e => (
                    e.FKDeviceId,
                    EmployeeNo: string.IsNullOrWhiteSpace(e.DeviceEmployeeNo)
                        ? e.DeviceUserId.ToString()
                        : e.DeviceEmployeeNo))
                .Select(g => g.First())
                .ToList();
        }

        public async Task<UnlinkedDeviceEnrollment?> GetUnlinkedEnrollmentByIdAsync(Guid id)
        {
            return await _dbContext.UnlinkedDeviceEnrollments
                .Include(e => e.AccessDevice)
                .FirstOrDefaultAsync(e => e.Id == id);
        }

        public async Task<bool> CustomerAccessIdExistsAsync(int id)
        {
            return await _dbContext.CustomerAccess.AnyAsync(c => c.Id == id);
        }
    }
}