using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using EPiServer.Core;
using EPiServer.Framework;
using EPiServer.Campaign.Commerce;
using EPiServer.ServiceLocation;
using EPiServer.Web.Routing;
using EPiServer.Commerce.Catalog.ContentTypes;
using EPiServer.Commerce.Catalog.Linking;
using EPiServer.Commerce.Marketing;
using Mediachase.Commerce.Pricing;

namespace EPiServer.Reference.Commerce.Site.Infrastructure
{
    [ServiceConfiguration(ServiceType = typeof(IProductFieldsHandler), Lifecycle = ServiceInstanceScope.Singleton)]
    internal class CustomProductFieldHandler : IProductFieldsHandler
    {
        private readonly IContentLoader _contentLoader;
        private readonly IUrlResolver _urlResolver;
        private readonly IRelationRepository _relationRepository;

        /// <summary>
        /// Initializes a new instance of the <see cref="DefaultProductLoader" /> class.
        /// </summary>
        /// <param name="contentLoader">The content loader.</param>
        /// <param name="relationRepository">The relation repository.</param>
        /// <param name="urlResolver">The url resolver.</param>
        public CustomProductFieldHandler(IContentLoader contentLoader, IRelationRepository relationRepository, IUrlResolver urlResolver)
        {
            _contentLoader = contentLoader;
            _relationRepository = relationRepository;
            _urlResolver = urlResolver;
        }

        /// <inheritdoc />
        public void PopulateCategoryFields(ProductModel model, EntryContentBase entry)
        {
            const string hashSymbol = "#";
            var entryAncestors = _contentLoader.GetAncestors(entry.ContentLink);
            var entryAncestorNames = entryAncestors.Reverse().Skip(1).Take(10).Select(a => a.Name.Replace(hashSymbol, string.Empty));

            model.Category = string.Join(hashSymbol, entryAncestorNames);
        }

        /// <inheritdoc />
        public void PopulateImageFields(ProductModel model, EntryContentBase entry)
        {
            var mediaCollection = entry.CommerceMediaCollection;

            if (mediaCollection == null || !entry.CommerceMediaCollection.Any())
            {
                return;
            }

            var contentImages = _contentLoader.GetItems(mediaCollection.Select(p => p.AssetLink), new LoaderOptions() { LanguageLoaderOption.MasterLanguage() })
                                              .OfType<IContentImage>()
                                              .Take(6)
                                              .ToArray();

            model.Image1 = contentImages.Length > 0 ? new ProductImageModel { ImageUrl = _urlResolver.GetUrl(contentImages[0].ContentLink) } : null;
            model.Image2 = contentImages.Length > 1 ? new ProductImageModel { ImageUrl = _urlResolver.GetUrl(contentImages[1].ContentLink) } : null;
            model.Image3 = contentImages.Length > 2 ? new ProductImageModel { ImageUrl = _urlResolver.GetUrl(contentImages[2].ContentLink) } : null;
            model.Image4 = contentImages.Length > 3 ? new ProductImageModel { ImageUrl = _urlResolver.GetUrl(contentImages[3].ContentLink) } : null;
            model.Image5 = contentImages.Length > 4 ? new ProductImageModel { ImageUrl = _urlResolver.GetUrl(contentImages[4].ContentLink) } : null;
            model.Image6 = contentImages.Length > 5 ? new ProductImageModel { ImageUrl = _urlResolver.GetUrl(contentImages[5].ContentLink) } : null;
        }

        /// <inheritdoc />
        public void PopulateTextFields(ProductModel model, EntryContentBase entry, IPriceValue price, IEnumerable<DiscountPrice> discountedPrices)
        {
            //Customized from DefaultProductFieldsHandler class
            model.Text1 = entry.DisplayName ?? string.Empty;
            model.Text2 = entry.Code;
            model.Text3 = GetProductUrl(entry) ?? string.Empty;
            model.Text4 = price.UnitPrice.ToString();
            model.Text5 = discountedPrices?.FirstOrDefault()?.Price.ToString() ?? string.Empty;
        }

        /// <inheritdoc />
        public void PopulateAdditionalDataFields(ProductModel model, EntryContentBase entry)
        {
        }

        /// <inheritdoc />
        public void PopulateLinkFields(ProductModel model, EntryContentBase entry)
        {
        }

        private string GetProductUrl(EntryContentBase entry)
        {
            var productUrl = _urlResolver.GetUrl(entry);

            if (productUrl != null)
            {
                return productUrl;
            }

            var parentProductLink = entry.GetParentProducts(_relationRepository).FirstOrDefault();

            return parentProductLink != null ? _urlResolver.GetUrl(parentProductLink) : string.Empty;
        }
    }

}