using Marco.Pms.Model.MongoDBModels.Expenses;
using Marco.Pms.Model.Utilities;
using Microsoft.Extensions.Configuration;
using MongoDB.Driver;

namespace Marco.Pms.Helpers.CacheHelper
{
    public class ExpenseCache
    {
        private readonly IMongoCollection<ExpenseDetailsMongoDB> _collection;
        public ExpenseCache(IConfiguration configuration)
        {

            var connectionString = configuration["MongoDB:ConnectionString"];
            var mongoUrl = new MongoUrl(connectionString);
            var client = new MongoClient(mongoUrl); // Your MongoDB connection string
            var mongoDB = client.GetDatabase(mongoUrl.DatabaseName);  // Your MongoDB Database name
            _collection = mongoDB.GetCollection<ExpenseDetailsMongoDB>("Expenses");
        }
        public async Task AddExpenseToCacheAsync(ExpenseDetailsMongoDB expense)
        {
            await _collection.InsertOneAsync(expense);

            await InitializeCollectionAsync();
        }
        public async Task AddExpensesListToCacheAsync(List<ExpenseDetailsMongoDB> expenses)
        {
            // 1. Add a guard clause to avoid an unnecessary database call for an empty list.
            if (expenses == null || !expenses.Any())
            {
                return;
            }

            // 2. Perform the insert operation. This is the only responsibility of this method.
            await _collection.InsertManyAsync(expenses);
            await InitializeCollectionAsync();
        }
        public async Task<(int totalPages, long totalCount, List<ExpenseDetailsMongoDB> expenseList)> GetExpenseListFromCacheAsync(Guid tenantId, Guid loggedInEmployeeId, bool viewAll,
            bool viewSelf, int pageNumber, int pageSize, ExpensesFilter? expenseFilter)
        {
            var filterBuilder = Builders<ExpenseDetailsMongoDB>.Filter;
            var filter = filterBuilder.Empty;

            // Permission-based filter
            if (!viewAll && viewSelf)
            {
                filter &= filterBuilder.Eq(e => e.CreatedById, loggedInEmployeeId.ToString());
            }

            // Apply filters
            if (expenseFilter != null)
            {
                if (expenseFilter.StartDate.HasValue && expenseFilter.EndDate.HasValue)
                {
                    filter &= filterBuilder.Gte(e => e.CreatedAt, expenseFilter.StartDate.Value.Date)
                           & filterBuilder.Lte(e => e.CreatedAt, expenseFilter.EndDate.Value.Date.AddDays(1).AddTicks(-1));
                }

                if (expenseFilter.ProjectIds?.Any() == true)
                {
                    filter &= filterBuilder.In(e => e.ProjectId, expenseFilter.ProjectIds.Select(p => p.ToString()).ToList());
                }

                if (expenseFilter.StatusIds?.Any() == true)
                {
                    filter &= filterBuilder.In(e => e.StatusId, expenseFilter.StatusIds.Select(p => p.ToString()).ToList());
                }

                if (expenseFilter.PaidById?.Any() == true)
                {
                    filter &= filterBuilder.In(e => e.PaidById, expenseFilter.PaidById.Select(p => p.ToString()).ToList());
                }

                if (expenseFilter.CreatedByIds?.Any() == true && viewAll)
                {
                    filter &= filterBuilder.In(e => e.CreatedById, expenseFilter.CreatedByIds.Select(p => p.ToString()).ToList());
                }
            }

            // Total count
            var totalCount = await _collection.CountDocumentsAsync(filter);
            var totalPages = (int)Math.Ceiling((double)totalCount / pageSize);

            // Fetch paginated data
            var expenses = await _collection
                .Find(filter)
                .Skip((pageNumber - 1) * pageSize)
                .Limit(pageSize)
                .SortByDescending(e => e.CreatedAt)
                .ToListAsync();

            return (totalPages, totalCount, expenses);
        }

        public async Task<ExpenseDetailsMongoDB> GetExpenseDetailsByIdAsync(Guid id, Guid tenantId)
        {
            var filter = Builders<ExpenseDetailsMongoDB>.Filter.And(
                    Builders<ExpenseDetailsMongoDB>.Filter.Eq(e => e.Id, id.ToString()),
                    Builders<ExpenseDetailsMongoDB>.Filter.Eq(e => e.TenantId, tenantId.ToString())
                );
            var expense = await _collection.Find(filter).FirstOrDefaultAsync();

            return expense;
        }

        public async Task<bool> DeleteExpenseFromCacheAsync(Guid id, Guid tenantId)
        {
            var filter = Builders<ExpenseDetailsMongoDB>.Filter.And(
                    Builders<ExpenseDetailsMongoDB>.Filter.Eq(e => e.Id, id.ToString()),
                    Builders<ExpenseDetailsMongoDB>.Filter.Eq(e => e.TenantId, tenantId.ToString())
                );
            var result = await _collection.DeleteOneAsync(filter);
            return result.DeletedCount > 0;
        }
        private async Task InitializeCollectionAsync()
        {
            var indexKeys = Builders<ExpenseDetailsMongoDB>.IndexKeys.Ascending(x => x.ExpireAt);
            var indexOptions = new CreateIndexOptions
            {
                ExpireAfter = TimeSpan.Zero // required for fixed expiration time
            };
            var indexModel = new CreateIndexModel<ExpenseDetailsMongoDB>(indexKeys, indexOptions);
            await _collection.Indexes.CreateOneAsync(indexModel);
        }
    }
}