using System.Text.Json;

namespace MesaFabApproval.Client.Services;

public interface IECNService {
    Task<string> ECNNumberIsValidStr(int ecnNumber);
    Task<bool> ECNNumberIsValid(int number);
}

public class ECNService : IECNService {
    private readonly IHttpClientFactory _httpClientFactory;

    public ECNService(IHttpClientFactory httpClientFactory) {
        _httpClientFactory = httpClientFactory ??
            throw new ArgumentNullException("IHttpClientFactory not injected");
    }

    public async Task<string> ECNNumberIsValidStr(int ecnNumber) {
        if (ecnNumber <= 0 || !await ECNNumberIsValid(ecnNumber))
            return $"{ecnNumber} is not a valid ECN#";

        return null;
    }

    public async Task<bool> ECNNumberIsValid(int number) {
        if (number <= 0) return false;

        try {
            HttpClient httpClient = _httpClientFactory.CreateClient("API");

            HttpRequestMessage requestMessage = new(HttpMethod.Get, $"ecn/isValidEcnNumber?number={number}");

            HttpResponseMessage responseMessage = await httpClient.SendAsync(requestMessage);

            if (responseMessage.IsSuccessStatusCode) {
                string responseContent = await responseMessage.Content.ReadAsStringAsync();

                JsonSerializerOptions jsonSerializerOptions = new() {
                    PropertyNameCaseInsensitive = true
                };

                bool isValid = JsonSerializer.Deserialize<bool>(responseContent, jsonSerializerOptions);

                return isValid;
            } else {
                throw new Exception(responseMessage.ReasonPhrase);
            }
        } catch (Exception ex) {
            throw new Exception($"Unable to determine if {number} is a valid ECN#, because {ex.Message}");
        }
    }
}