using System.Collections.Concurrent;
using FrontOffice.BFF.Products.Protobuf.Protos.Products;

namespace FrontOffice.Main.Utilities;

public record Product(
    long Id,
    string Title,
    string Description,
    string ImageUrl,
    long Price,
    int Discount = 0,
    int Rate = 0,
    int RemainingCount = 0);

public class ProductService
{
    private static readonly List<Product> _seed = new()
    {
        new(1, "ماسک پزشکی سه‌لایه", "ماسک سه‌لایه با فیلتراسیون بالا مناسب برای محیط‌های عمومی.", "/images/store/mask.jpg", 49000),
        new(2, "دستکش لاتکس", "دستکش لاتکس مناسب معاینات پزشکی، بدون پودر.", "/images/store/gloves.jpg", 89000),
        new(3, "محلول ضدعفونی کننده", "محلول ضدعفونی بر پایه الکل ۷۰٪ مناسب دست و سطوح.", "/images/store/sanitizer.jpg", 69000),
        new(4, "تب‌سنج دیجیتال", "تب‌سنج دیجیتال با دقت بالا و نمایشگر LCD.", "/images/store/thermometer.jpg", 299000),
        new(5, "فشارسنج دیجیتال", "فشارسنج بازویی دیجیتال با حافظه داخلی.", "/images/store/bp-monitor.jpg", 1259000)
    };

    private readonly ConcurrentDictionary<long, Product> _cache = new();
    private readonly ProductsContract.ProductsContractClient _client;

    public ProductService(ProductsContract.ProductsContractClient client)
    {
        _client = client;
        foreach (var p in _seed) _cache[p.Id] = p;
    }

    public async Task<List<Product>> GetProductsAsync(string? query = null)
    {
        try
        {
            var resp = await _client.GetAllProductsByFilterAsync(new GetAllProductsByFilterRequest
            {
                Filter = new GetAllProductsByFilterFilter
                {
                    Title = query ?? string.Empty,
                    Description = query ?? string.Empty,
                    ShortInfomation = query ?? string.Empty,
                    FullInformation = query ?? string.Empty
                }
            });
            return MapAndCache(resp.Models);
        }
        catch
        {
            IEnumerable<Product> list = _cache.Values;
            if (!string.IsNullOrWhiteSpace(query))
            {
                var q = query.Trim();
                list = list.Where(p => p.Title.Contains(q, StringComparison.OrdinalIgnoreCase) || p.Description.Contains(q, StringComparison.OrdinalIgnoreCase));
            }
            return list.OrderBy(p => p.Id).ToList();
        }
    }

    public async Task<Product?> GetByIdAsync(long id)
    {
        if (_cache.TryGetValue(id, out var cached)) return cached;

        try
        {
            // No single-get endpoint exposed: fetch list and pick
            var resp = await _client.GetAllProductsByFilterAsync(new GetAllProductsByFilterRequest { Filter = new GetAllProductsByFilterFilter() });
            var list = MapAndCache(resp.Models);
            return list.FirstOrDefault(x => x.Id == id);
        }
        catch
        {
            _cache.TryGetValue(id, out var result);
            return result;
        }
    }

    private List<Product> MapAndCache(Google.Protobuf.Collections.RepeatedField<GetAllProductsByFilterResponseModel> models)
    {
        var list = new List<Product>();
        foreach (var m in models)
        {
            var p = new Product(
                Id: m.Id,
                Title: m.Title ?? string.Empty,
                Description: m.Description ?? string.Empty,
                ImageUrl: string.IsNullOrWhiteSpace(m.ImagePath) ? string.Empty : UrlUtility.DownloadUrl + m.ImagePath,
                Price: m.Price,
                Discount: m.Discount,
                Rate: m.Rate,
                RemainingCount: m.RemainingCount
            );
            _cache[p.Id] = p;
            list.Add(p);
        }
        return list;
    }
}