namespace GrossesMitainesAPI.Controllers;

#region Dependencies
using Microsoft.AspNetCore.Mvc;
using GrossesMitainesAPI.Models;
using System.Linq;
using GrossesMitainesAPI.Data;
using Microsoft.Extensions.Logging;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Cors;
using GrossesMitainesAPI.Services;
using System.Collections.Immutable;

#endregion

[EnableCors("_myAllowSpecificOrigins"), ApiController, Route("api/[controller]"), 
 Authorize(AuthenticationSchemes = "Identity.Application")]
public class SearchController : Controller {
    #region Constants
    private const int PREVIEW = 4;

    #endregion

    #region DI Fields
    private readonly ILogger<SearchController> _logger;
    private readonly InventoryContext _context;
    private readonly DatabaseCacheService _cache;
    private IQueryable<ProductModel>? _searchCache = null;

    #endregion

    #region Ctor
    public SearchController(ILogger<SearchController> logger, InventoryContext context, DatabaseCacheService cache) {
        _logger = logger;
        _context = context;
        _cache = cache;
        if (_cache.isOk())
            _searchCache = _cache.queryCache();
    }

    #endregion

    #region API Methods
    [EnableCors("_myAllowSpecificOrigins"), HttpGet(Name = "Search"), AllowAnonymous]
    public IEnumerable<ProductViewModel> Get(string query, bool? preview, string? filterPrice, string? filterState, string? order = "Relevance") {
        if (preview.HasValue && preview == true)
            return _searchCache is null ?
                _context.Products.Where(x => x.Title.Contains(query)).Take(PREVIEW).Select(x => new ProductViewModel(x)).ToList() :
                _searchCache.Where(x => x.Title.Contains(query)).Take(PREVIEW).Select(x => new ProductViewModel(x)).ToList();
        return Search(query, filterPrice, filterState, order);
    }

    #endregion

    #region Internal Methods
    private List<ProductViewModel> Search(string query, string? filterPrice, string? filterState, string? order) {
        List<ProductViewModel> products = new();
        query = query.Trim();
        try {
            query = query.ToLower();
            IQueryable<ProductViewModel> ret;
            if (_searchCache is null) {
                _logger.LogError(8, "Erreur de cache.");
                ret = _context.Products.AsQueryable().Select(x => new ProductViewModel(x));
            } else ret = _searchCache.Select(x => new ProductViewModel(x));

            switch (filterPrice) {
                case "PriceUnder20":
                    ret = ret.Where(x => x.Price < 20);
                    break;
                case "Price20to49":
                    ret = ret.Where(x => x.Price >= 20 && x.Price < 50);
                    break;
                case "Price50to99":
                    ret = ret.Where(x => x.Price >= 50 && x.Price < 100);
                    break;
                case "PriceOver100":
                    ret = ret.Where(x => x.Price >= 100);
                    break;
                default: break;
            }
            switch (filterState) {
                case "isAvailable":
                    ret = ret.Where(x => x.Status == ProductModel.States.Available);
                    break;
                case "isUnavailable":
                    ret = ret.Where(x => x.Status == ProductModel.States.Unavailable);
                    break;
                case "isBackOrder":
                    ret = ret.Where(x => x.Status == ProductModel.States.BackOrder);
                    break; ;
                case "isClearance":
                    ret = ret.Where(x => x.Status == ProductModel.States.Clearance);
                    break;
                case "isDiscontinued":
                    ret = ret.Where(x => x.Status == ProductModel.States.Discontinued);
                    break;
                case "isPromoted":
                    ret = ret.Where(x => x.Status == ProductModel.States.Clearance || x.Status == ProductModel.States.Promotion);
                    break;
                default: break;
            }

            switch (order) {
                case "Relevance":
                    List<ProductViewModel> title = new(), desc = new(), cat = new();
                    foreach (ProductViewModel prod in ret.ToList()) {
                        string sTitle = prod.Title.Replace(",", " ").ToLower() + " ",
                               sCat = " " + prod.Category.ToLower() + " ",
                               sDesc = prod.Description.Replace(".", " ").Replace(",", " ").ToLower() + " ";
                        if (sTitle.StartsWith(query))
                            products.Add(prod);
                        else if (sTitle.Contains(" " + query))
                            title.Add(prod);
                        else if (sDesc.Contains(" " + query))
                            desc.Add(prod);
                        else if (sCat.Contains(" " + query))
                            cat.Add(prod);
                    }
                    products.AddRange(title);
                    products.AddRange(desc);
                    products.AddRange(cat);
                    break;
                case "Price":
                    ret = ret.OrderBy(x => x.Status == ProductModel.States.Promotion || x.Status == ProductModel.States.Clearance ? x.PromoPrice : x.Price);
                    goto default;
                case "PriceDesc":
                    ret = ret.OrderByDescending(x => x.Status == ProductModel.States.Promotion || x.Status == ProductModel.States.Clearance ? x.PromoPrice : x.Price);
                    goto default;
                case "Title":
                    ret = ret.OrderBy(x => x.Title);
                    goto default;
                case "TitleDesc":
                    ret = ret.OrderByDescending(x => x.Title);
                    goto default;
                case "Category":
                    ret = ret.OrderBy(x => x.Category);
                    goto default;
                case "CategoryDesc":
                    ret = ret.OrderByDescending(x => x.Category);
                    goto default;
                default:
                    foreach (ProductViewModel prod in ret.ToList()) {
                        string sTitle = prod.Title.Replace(",", " ").ToLower() + " ",
                               sCat = " " + prod.Category.ToLower() + " ",
                               sDesc = prod.Description.Replace(".", " ").Replace(",", " ").ToLower() + " ";
                        if (sTitle.StartsWith(query)
                         || sTitle.Contains(" " + query + " ")
                         || sDesc.StartsWith(query) || sDesc.Contains(" " + query + " ")
                         || sCat.Contains(" " + query + " "))
                            products.Add(prod);
                    }
                    break;
            }
        } catch (Exception e) {
            _logger.LogError(8, e.Message);
            return new List<ProductViewModel>();
        }
        return products;
    }

    #endregion
}