using Microsoft.AspNetCore.WebUtilities;
using Microsoft.Extensions.Options;
using Somnia.GuestLog.Models.Configuration;
using Somnia.GuestLog.Models.DTOs;
using Somnia.GuestLog.Utils;

namespace Somnia.GuestLog.Services.AddressQuery;

public class NominatimAddressQueryService(
    IHttpClientFactory httpClientFactory,
    ILogger<NominatimAddressQueryService> logger,
    IOptions<AddressQueryConfig> configOptions
) : IAddressQueryService
{
    private const string defaultBaseAddr = "https://nominatim.openstreetmap.org";
    private const string defaultUserAgent = "Somnia-GuestLog";
    private const string apiUri = "/search";

    private readonly AddressQueryConfig config = configOptions.Value;


    public async Task<List<AddressResultDTO>> SearchAddressAsync(string query)
    {
        var http = GetHttpClient();
        List<AddressResultDTO> rsList = [];

        try
        {
            string uri = GetRequestUri(query);
            List<ApiResult> apiList = (await http.GetFromJsonAsync<List<ApiResult>>(uri)) ?? [];

            foreach (ApiResult result in apiList)
            {
                if (result.Address is null)
                {
                    logger.LogWarning("Skipping result without address details. '{result}'", result);
                    continue;
                }

                string? alpha3CountryCode = CountryCodesUtils.Alpha2ToAlpha3(result.Address.Country_code);

                rsList.Add(new()
                {
                    HouseNumber = result.Address.House_number,
                    AddressRoad = result.Address.Road ?? result.Address.Square,
                    AddressCity = result.Address.City ?? result.Address.Municipality ?? result.Address.Town ?? result.Address.Village,
                    AddressProvince = result.Address.Province,
                    AddressState = result.Address.State,
                    AddressCountry = result.Address.Country,
                    ZipCode = result.Address.Postcode,
                    AddressCountryCode = alpha3CountryCode
                });
            }

            return rsList;
        }
        catch (System.Exception ex)
        {
            logger.LogError(ex, "Error getting info from API!");
            return [];
        }
    }


    private HttpClient GetHttpClient()
    {
        HttpClient client = httpClientFactory.CreateClient();

        Uri baseAddr = new(config.ServiceURL ?? defaultBaseAddr);

        client.BaseAddress = baseAddr;
        client.DefaultRequestHeaders.UserAgent.ParseAdd(config.UserAgent ?? defaultUserAgent);
        if (config.ResultLang is not null)
        {
            client.DefaultRequestHeaders.AcceptLanguage.ParseAdd(config.ResultLang);
        }

        return client;
    }

    private static string GetRequestUri(string query)
    {
        return QueryHelpers.AddQueryString(apiUri, [
            new KeyValuePair<string, string?>("format", "jsonv2"),
            new KeyValuePair<string, string?>("addressdetails", "1"),
            new KeyValuePair<string, string?>("layer", "address"),
            new KeyValuePair<string, string?>("q", query),
        ]);
    }

    private record class ApiResultAddress(
        string? House_number = null,
        string? Road = null,
        string? Square = null,
        string? City = null,
        string? Municipality = null,
        string? Village = null,
        string? Town = null,
        string? Province = null,
        string? State = null,
        string? Country = null,
        string? Postcode = null,
        string? Country_code = null
    );

    private record class ApiResult(
        string? Osm_type = null,
        long? Osm_id = null,
        string? Category = null,
        string? AddressType = null,
        string? Name = null,
        string? Display_name = null,
        ApiResultAddress? Address = null
    );


}