using Elwig.Helpers;
using Elwig.Models.Entities;
using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text.Json.Nodes;
using System.Threading.Tasks;
using System.Web;

namespace Elwig.Services {
    public static class OrganicService {

        public const string TRACES_API_URL = "https://webgate.ec.europa.eu/tracesnt/directory/publication/organic-operator/for/query";
        public const string TRACES_PDF_URL_PREFIX = "https://webgate.ec.europa.eu/tracesnt/directory/publication/organic-operator/digitally-signed/";

        public enum TracesStatus {
            ISSUED, SUSPENDED, WITHDRAWN, EXPIRED
        }

        public enum TracesActivity {
            PREPARATION, EXPORT, IMPORT, STORING, PRODUCTION, DISTRIBUTION, DISTRIBUTION_PLACING_ON_THE_MARKET
        }

        public enum TracesCategoryOfProduct {
            UNPROCESSED_PLANT_PRODUCTS_INCLUDING_SEEDS, LIVESTOCK_AND_UNPROCESSED_LIVESTOCK_PRODUCTS, ALGAE_AND_UNPROCESSED_AQUACULTURE_PRODUCTS,
            PROCESSED_AGRICULTURAL_PRODUCTS_INCLUDING_AQUACULTURE_FOR_USE_AS_FOOD, FEED, WINE, OTHER_PRODUCTS_NOT_COVERED_BY_PREVIOUS_CATEGORIES
        }

        public record TracesCertificate {
            public required string Id { get; init; }
            public required string AuthorityCode { get; init; }
            public required string OperatorId { get; init; }
            public required string OperatorName { get; init; }
            public required TracesActivity[] Activities { get; init; }
            public required TracesCategoryOfProduct[] CategoriesOfProduct { get; init; }
            public required DateOnly IssuedOn { get; init; }
            public required DateOnly ExpiresOn { get; init; }
            public required DateOnly LastStatusUpdateOn { get; init; }
            public required TracesStatus Status { get; init; }

            public string PdfUrl => TRACES_PDF_URL_PREFIX + Id + ".pdf";
            public bool IsValid => Status == TracesStatus.ISSUED && IssuedOn.ToDateTime(new()) <= DateTime.Today && ExpiresOn.ToDateTime(new()) >= DateTime.Today;
            public bool IsValidForWineProduction => IsValid && Activities.Contains(TracesActivity.PRODUCTION) &&
                (CategoriesOfProduct.Contains(TracesCategoryOfProduct.UNPROCESSED_PLANT_PRODUCTS_INCLUDING_SEEDS) || CategoriesOfProduct.Contains(TracesCategoryOfProduct.WINE));
        }

        private async static Task<JsonArray> TryFetchTracesCertificates(Dictionary<string, string> query) {
            var q = HttpUtility.ParseQueryString("");
            q.Add("sort", "-issuedOn");
            q.Add("countryCode", "AT");
            foreach (var (k, v) in query) {
                q.Add(k, v);
            }

            using var client = Utils.GetHttpClient();
            using var res = await client.GetAsync($"{TRACES_API_URL}?{q}");
            res.EnsureSuccessStatusCode();
            var resJson = JsonNode.Parse(await res.Content.ReadAsStringAsync());
            var certs = resJson?.AsArray() ?? throw new Exception();
            if (certs.Count == 0)
                throw new Exception();
            return certs;
        }

        public async static Task<TracesCertificate[]> FetchTracesCertificatesOfMember(Member m, bool? tryNameAndAddress = null) {
            bool searchedByName = false;

            JsonArray? jsonCerts = null;
            if (m.OrganicOperatorId != null) {
                try {
                    jsonCerts = await TryFetchTracesCertificates(new Dictionary<string, string> {
                        { "operatorIdentifierType", "ooc_identifier" },
                        { "operatorIdentifierSearchOperator", "STRICT" },
                        { "operatorIdentifier", m.OrganicOperatorId },
                    });
                } catch {
                    jsonCerts = null;
                }
            }
            
            if (jsonCerts == null && m.LfbisNr != null) {
                try {
                    jsonCerts = await TryFetchTracesCertificates(new Dictionary<string, string> {
                        { "operatorIdentifierType", "comp_reg" },
                        { "operatorIdentifierSearchOperator", "STRICT" },
                        { "operatorIdentifier", m.LfbisNr.TrimStart('0') },
                    });
                } catch {
                    jsonCerts = null;
                }
            }
                
            if (jsonCerts == null && (tryNameAndAddress ?? m.IsOrganic)) {
                try {
                    jsonCerts = await TryFetchTracesCertificates(new Dictionary<string, string> {
                        { "operatorPostalCode", $"{(m.BillingAddress?.PostalDest ?? m.PostalDest).AtPlz?.Plz}" },
                        { "query", m.BillingAddress is BillingAddr a ? $"{a.FullName} {a.Address}" : $"{m.FullName} {m.Address}" },
                    });
                    searchedByName = true;
                } catch {
                    jsonCerts = null;
                }
            }

            if (jsonCerts == null)
                return [];

            TracesCertificate[] certs = [];
            try {
                certs = [.. jsonCerts.Select(j => new TracesCertificate {
                    Id = j!["reference"]?.GetValue<string>() ?? throw new Exception(),
                    AuthorityCode = j["issuingBody"]?["code"]?.GetValue<string>() ?? throw new Exception(),
                    OperatorId = j["operatorIdentifier"]?.GetValue<string>() ?? throw new Exception(),
                    OperatorName = j["operator"]?["name"]?.GetValue<string>() ?? throw new Exception(),
                    Activities = [.. j["activities"]?.AsArray().Select(a => Enum.Parse<TracesActivity>(a?["id"]?.GetValue<string>().ToUpper().Replace("_IMPORT", "IMPORT") ?? throw new Exception())) ?? []],
                    CategoriesOfProduct = [.. j["categoriesOfProduct"]?.AsArray().Select(c => Enum.Parse<TracesCategoryOfProduct>(c?["id"]?.GetValue<string>() ?? throw new Exception())) ?? []],
                    IssuedOn = DateOnly.FromDateTime(DateTime.ParseExact(j["issuedOn"]?.GetValue<string>() ?? throw new Exception(), "yyyy-MM-ddTHH:mm:ss.fffK", CultureInfo.InvariantCulture, DateTimeStyles.None)),
                    ExpiresOn = DateOnly.ParseExact(j["expiresOn"]?.GetValue<string>() ?? throw new Exception(), "yyyy-MM-dd"),
                    LastStatusUpdateOn = DateOnly.FromDateTime(DateTime.ParseExact(j["lastStatusUpdateDateTime"]?.GetValue<string>() ?? throw new Exception(), "yyyy-MM-ddTHH:mm:ss.fffK", CultureInfo.InvariantCulture, DateTimeStyles.None)),
                    Status = Enum.Parse<TracesStatus>(j["status"]?["id"]?.GetValue<string>() ?? throw new Exception()),
                })];
            } catch {
                return [];
            }

            return (!searchedByName || certs.Where(c => c.Status == TracesStatus.ISSUED).Select(c => c.OperatorId).ToHashSet().Count == 1) ? certs : [];
        }


    }
}