using System.Collections.Generic;
using Microsoft.EntityFrameworkCore;
using CMSMicroservice.Application.Common.Interfaces;
using CMSMicroservice.Application.Common.Interfaces.Repositories;
using CMSMicroservice.Domain.Entities;
using CMSMicroservice.Domain.Enums;

namespace CMSMicroservice.Infrastructure.Persistence.Repositories;

/// <summary>
/// Repository implementation برای مدیریت حرکات موجودی
/// </summary>
public class StockMovementRepository : IStockMovementRepository
{
    private readonly IApplicationDbContext _context;

    public StockMovementRepository(IApplicationDbContext context)
    {
        _context = context;
    }

    #region Read Operations

    public async Task<StockMovement?> GetByIdAsync(long id, CancellationToken cancellationToken = default)
    {
        return await _context.StockMovements
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.Product)
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.DiscountProduct)
            .FirstOrDefaultAsync(m => m.Id == id, cancellationToken);
    }

    public async Task<List<StockMovement>> GetByInventoryItemIdAsync(
        long inventoryItemId,
        StockMovementType? movementType = null,
        DateTime? fromDate = null,
        DateTime? toDate = null,
        int skip = 0,
        int take = 100,
        CancellationToken cancellationToken = default)
    {
        var query = _context.StockMovements
            .Include(m => m.InventoryItem)
            .Where(m => m.InventoryItemId == inventoryItemId);

        if (movementType.HasValue)
        {
            query = query.Where(m => m.MovementType == movementType.Value);
        }

        if (fromDate.HasValue)
        {
            query = query.Where(m => m.Created >= fromDate.Value);
        }

        if (toDate.HasValue)
        {
            query = query.Where(m => m.Created <= toDate.Value);
        }

        return await query
            .OrderByDescending(m => m.Created)
            .Skip(skip)
            .Take(take)
            .ToListAsync(cancellationToken);
    }

    public async Task<List<StockMovement>> GetByOrderIdAsync(long orderId, CancellationToken cancellationToken = default)
    {
        return await _context.StockMovements
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.Product)
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.DiscountProduct)
            .Where(m => m.OrderId == orderId)
            .OrderByDescending(m => m.Created)
            .ToListAsync(cancellationToken);
    }

    public async Task<List<StockMovement>> GetByDiscountOrderIdAsync(long discountOrderId, CancellationToken cancellationToken = default)
    {
        return await _context.StockMovements
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.Product)
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.DiscountProduct)
            .Where(m => m.DiscountOrderId == discountOrderId)
            .OrderByDescending(m => m.Created)
            .ToListAsync(cancellationToken);
    }

    public async Task<List<StockMovement>> GetByReferenceNumberAsync(string referenceNumber, CancellationToken cancellationToken = default)
    {
        return await _context.StockMovements
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.Product)
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.DiscountProduct)
            .Where(m => m.ReferenceNumber == referenceNumber)
            .OrderByDescending(m => m.Created)
            .ToListAsync(cancellationToken);
    }

    public async Task<List<StockMovement>> GetByMovementTypeAsync(
        StockMovementType movementType,
        DateTime? fromDate = null,
        DateTime? toDate = null,
        int skip = 0,
        int take = 100,
        CancellationToken cancellationToken = default)
    {
        var query = _context.StockMovements
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.Product)
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.DiscountProduct)
            .Where(m => m.MovementType == movementType);

        if (fromDate.HasValue)
        {
            query = query.Where(m => m.Created >= fromDate.Value);
        }

        if (toDate.HasValue)
        {
            query = query.Where(m => m.Created <= toDate.Value);
        }

        return await query
            .OrderByDescending(m => m.Created)
            .Skip(skip)
            .Take(take)
            .ToListAsync(cancellationToken);
    }

    public async Task<List<StockMovement>> GetRecentMovementsAsync(
        int count = 50,
        StockMovementType? movementType = null,
        CancellationToken cancellationToken = default)
    {
        var query = _context.StockMovements
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.Product)
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.DiscountProduct)
            .AsQueryable();

        if (movementType.HasValue)
        {
            query = query.Where(m => m.MovementType == movementType.Value);
        }

        return await query
            .OrderByDescending(m => m.Created)
            .Take(count)
            .ToListAsync(cancellationToken);
    }

    public async Task<List<StockMovement>> SearchAsync(
        long? inventoryItemId = null,
        StockMovementType? movementType = null,
        DateTime? fromDate = null,
        DateTime? toDate = null,
        string? referenceNumber = null,
        long? orderId = null,
        long? discountOrderId = null,
        long? performedByUserId = null,
        int skip = 0,
        int take = 100,
        CancellationToken cancellationToken = default)
    {
        var query = _context.StockMovements
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.Product)
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.DiscountProduct)
            .AsQueryable();

        if (inventoryItemId.HasValue)
        {
            query = query.Where(m => m.InventoryItemId == inventoryItemId.Value);
        }

        if (movementType.HasValue)
        {
            query = query.Where(m => m.MovementType == movementType.Value);
        }

        if (fromDate.HasValue)
        {
            query = query.Where(m => m.Created >= fromDate.Value);
        }

        if (toDate.HasValue)
        {
            query = query.Where(m => m.Created <= toDate.Value);
        }

        if (!string.IsNullOrWhiteSpace(referenceNumber))
        {
            query = query.Where(m => m.ReferenceNumber != null && m.ReferenceNumber.Contains(referenceNumber));
        }

        if (orderId.HasValue)
        {
            query = query.Where(m => m.OrderId == orderId.Value);
        }

        if (discountOrderId.HasValue)
        {
            query = query.Where(m => m.DiscountOrderId == discountOrderId.Value);
        }

        if (performedByUserId.HasValue)
        {
            query = query.Where(m => m.PerformedByUserId == performedByUserId.Value);
        }

        return await query
            .OrderByDescending(m => m.Created)
            .Skip(skip)
            .Take(take)
            .ToListAsync(cancellationToken);
    }

    public async Task<int> CountAsync(
        long? inventoryItemId = null,
        StockMovementType? movementType = null,
        DateTime? fromDate = null,
        DateTime? toDate = null,
        string? referenceNumber = null,
        long? orderId = null,
        long? discountOrderId = null,
        long? performedByUserId = null,
        CancellationToken cancellationToken = default)
    {
        var query = _context.StockMovements.AsQueryable();

        if (inventoryItemId.HasValue)
        {
            query = query.Where(m => m.InventoryItemId == inventoryItemId.Value);
        }

        if (movementType.HasValue)
        {
            query = query.Where(m => m.MovementType == movementType.Value);
        }

        if (fromDate.HasValue)
        {
            query = query.Where(m => m.Created >= fromDate.Value);
        }

        if (toDate.HasValue)
        {
            query = query.Where(m => m.Created <= toDate.Value);
        }

        if (!string.IsNullOrWhiteSpace(referenceNumber))
        {
            query = query.Where(m => m.ReferenceNumber != null && m.ReferenceNumber.Contains(referenceNumber));
        }

        if (orderId.HasValue)
        {
            query = query.Where(m => m.OrderId == orderId.Value);
        }

        if (discountOrderId.HasValue)
        {
            query = query.Where(m => m.DiscountOrderId == discountOrderId.Value);
        }

        if (performedByUserId.HasValue)
        {
            query = query.Where(m => m.PerformedByUserId == performedByUserId.Value);
        }

        return await query.CountAsync(cancellationToken);
    }

    #endregion

    #region Write Operations

    public async Task<StockMovement> AddAsync(StockMovement stockMovement, CancellationToken cancellationToken = default)
    {
        _context.StockMovements.Add(stockMovement);
        await _context.SaveChangesAsync(cancellationToken);
        return stockMovement;
    }

    public async Task DeleteAsync(long id, CancellationToken cancellationToken = default)
    {
        var stockMovement = await _context.StockMovements.FindAsync(new object[] { id }, cancellationToken);
        if (stockMovement != null)
        {
            _context.StockMovements.Remove(stockMovement);
            await _context.SaveChangesAsync(cancellationToken);
        }
    }

    public async Task<List<StockMovement>> BulkAddAsync(List<StockMovement> stockMovements, CancellationToken cancellationToken = default)
    {
        _context.StockMovements.AddRange(stockMovements);
        await _context.SaveChangesAsync(cancellationToken);
        return stockMovements;
    }

    #endregion

    #region Analytics & Reports

    public async Task<Dictionary<StockMovementType, int>> GetMovementSummaryAsync(
        DateTime fromDate,
        DateTime toDate,
        long? inventoryItemId = null,
        CancellationToken cancellationToken = default)
    {
        var query = _context.StockMovements
            .Where(m => m.Created >= fromDate && m.Created <= toDate);

        if (inventoryItemId.HasValue)
        {
            query = query.Where(m => m.InventoryItemId == inventoryItemId.Value);
        }

        var movements = await query
            .GroupBy(m => m.MovementType)
            .Select(g => new { MovementType = g.Key, TotalQuantity = g.Sum(m => m.Quantity) })
            .ToListAsync(cancellationToken);

        return movements.ToDictionary(x => x.MovementType, x => x.TotalQuantity);
    }

    public async Task<List<(DateTime Date, int InboundQuantity, int OutboundQuantity)>> GetDailyMovementVolumeAsync(
        DateTime fromDate,
        DateTime toDate,
        long? inventoryItemId = null,
        CancellationToken cancellationToken = default)
    {
        var query = _context.StockMovements
            .Where(m => m.Created >= fromDate && m.Created <= toDate);

        if (inventoryItemId.HasValue)
        {
            query = query.Where(m => m.InventoryItemId == inventoryItemId.Value);
        }

        var movements = await query.ToListAsync(cancellationToken);

        // نوع‌های ورودی (افزایش موجودی)
        var inboundTypes = new[]
        {
            StockMovementType.InitialStock,
            StockMovementType.Restock,
            StockMovementType.Return,
            StockMovementType.TransferIn,
            StockMovementType.AdjustmentPlus,
            StockMovementType.Released
        };

        // نوع‌های خروجی (کاهش موجودی)
        var outboundTypes = new[]
        {
            StockMovementType.Sale,
            StockMovementType.Damaged,
            StockMovementType.Lost,
            StockMovementType.TransferOut,
            StockMovementType.AdjustmentMinus,
            StockMovementType.Reserved
        };

        var dailyVolumes = movements
            .GroupBy(m => m.Created.Date)
            .Select(g => (
                Date: g.Key,
                InboundQuantity: g.Where(m => inboundTypes.Contains(m.MovementType)).Sum(m => m.Quantity),
                OutboundQuantity: g.Where(m => outboundTypes.Contains(m.MovementType)).Sum(m => m.Quantity)
            ))
            .OrderBy(x => x.Date)
            .ToList();

        return dailyVolumes;
    }

    public async Task<List<(long InventoryItemId, string ProductName, int MovementCount, int TotalQuantityChange)>> GetTopMovingProductsAsync(
        DateTime fromDate,
        DateTime toDate,
        int count = 10,
        StockMovementType? movementType = null,
        CancellationToken cancellationToken = default)
    {
        var query = _context.StockMovements
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.Product)
            .Include(m => m.InventoryItem)
                .ThenInclude(i => i.DiscountProduct)
            .Where(m => m.Created >= fromDate && m.Created <= toDate);

        if (movementType.HasValue)
        {
            query = query.Where(m => m.MovementType == movementType.Value);
        }

        var movements = await query.ToListAsync(cancellationToken);

        var topProducts = movements
            .GroupBy(m => m.InventoryItemId)
            .Select(g =>
            {
                var firstItem = g.First().InventoryItem;
                var productName = firstItem.Product?.Title ?? firstItem.DiscountProduct?.Title ?? "Unknown";
                return (
                    InventoryItemId: g.Key,
                    ProductName: productName,
                    MovementCount: g.Count(),
                    TotalQuantityChange: g.Sum(m => m.Quantity)
                );
            })
            .OrderByDescending(x => x.MovementCount)
            .Take(count)
            .ToList();

        return topProducts;
    }

    #endregion
}