using System.Text;
using System.Text.Json;

using MesaFabApproval.Shared.Models;

using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;

using static System.Net.Mime.MediaTypeNames;

namespace MesaFabApproval.Shared.Services;

public interface IMonInWorkerClient {
    void PostAverage(string metricName, double metricValue);
    void PostCount(string metricName, double metricValue);
    void PostStatus(string statusName, StatusValue statusValue);
}

public class MonInWorkerClient : IMonInWorkerClient {
    private readonly IHttpClientFactory _httpClientFactory;
    private readonly IConfiguration _config;
    private readonly ILogger<MonInWorkerClient> _logger;

    private readonly string _baseUrl;
    private readonly int _retryLimit = -1;
    private readonly int _backoffInSeconds = -1;

    private readonly string _resource;

    public MonInWorkerClient(IHttpClientFactory httpClientFactory,
                             IConfiguration config,
                             ILogger<MonInWorkerClient> logger) {
        _httpClientFactory = httpClientFactory;
        if (_httpClientFactory is null) throw new ArgumentNullException("IHttpClientFactory not injected");

        _config = config;
        if (_config is null) throw new ArgumentNullException("IConfiguration not injected");

        _logger = logger;
        if (_logger is null) throw new ArgumentNullException("ILogger not injected");

        _baseUrl = Environment.GetEnvironmentVariable("MonInWorkerUrl") ??
            throw new ArgumentNullException("MonInWorkerUrl environment variable not found");

        string monInRetries = Environment.GetEnvironmentVariable("MonInRetries") ??
            throw new ArgumentNullException("MonInRetries environment variable not found");
        if (!Int32.TryParse(monInRetries, out _retryLimit))
            throw new ArgumentException("MonInReties environment variable not an integer");

        string monInBackoffSeconds = Environment.GetEnvironmentVariable("MonInBackoffSeconds") ??
            throw new ArgumentNullException("MonInBackoffSeconds environment variable not found");
        if (!Int32.TryParse(monInBackoffSeconds, out _backoffInSeconds))
            throw new ArgumentException("MonInBackoffSeconds environment variable not an integer");

        _resource = Environment.GetEnvironmentVariable("FabApprovalApiMonInResource") ??
            throw new ArgumentNullException("OIWizardMonInResource environment variable not found");
    }

    public async void PostStatus(string statusName, StatusValue statusValue) {
        string url = _baseUrl + "status";

        StringBuilder logBuilder = new();
        logBuilder.Append($"Attempting to send MonIn status request for resource {_resource} ");
        logBuilder.Append($"with name {statusName} and value {statusValue.ToString()} to url {url}");
        _logger.LogInformation(logBuilder.ToString());

        try {
            bool success = false;
            int retries = _retryLimit;
            while (!success && retries > 0) {
                Task.Delay(TimeSpan.FromSeconds((_retryLimit - retries) * _backoffInSeconds)).Wait();

                HttpClient httpClient = _httpClientFactory.CreateClient();

                RawMonInStatusRequest statusRequest = new RawMonInStatusRequest() {
                    resource = _resource,
                    dateTime = DateTime.Now,
                    statusName = statusName,
                    statusValue = statusValue.ToString()
                };

                StringContent statusRequestJson = new StringContent(JsonSerializer.Serialize(statusRequest),
                                                          Encoding.UTF8,
                                                          Application.Json);

                using HttpResponseMessage httpResponseMessage = await httpClient.PostAsync(url, statusRequestJson);

                success = httpResponseMessage.IsSuccessStatusCode;
                retries--;
            }
        } catch (Exception ex) {
            StringBuilder errLogBuilder = new();
            errLogBuilder.Append($"An exception occurred when attempting to send MonIn status request for resource {_resource} ");
            errLogBuilder.Append($"with name {statusName} and value {statusValue.ToString()} to url {url}. Exception: {ex.Message}");
            _logger.LogError(errLogBuilder.ToString());
        }
    }

    public async void PostCount(string metricName, double metricValue) {
        string url = _baseUrl + "count";

        StringBuilder logMsgBuilder = new();
        logMsgBuilder.Append($"Attempting to send MonIn count request for resource {_resource} ");
        logMsgBuilder.Append($"with name {metricName} and value {metricValue} to url {url}");
        _logger.LogInformation(logMsgBuilder.ToString());

        try {
            bool success = false;
            int retries = _retryLimit;
            while (!success && retries > 0) {
                Task.Delay(TimeSpan.FromSeconds((_retryLimit - retries) * _backoffInSeconds)).Wait();

                HttpClient httpClient = _httpClientFactory.CreateClient();

                MonInMetricRequest metricRequest = new MonInMetricRequest() {
                    resource = _resource,
                    dateTime = DateTime.Now,
                    metricName = metricName,
                    metricValue = metricValue
                };

                StringContent metricRequestJson = new StringContent(JsonSerializer.Serialize(metricRequest),
                                                          Encoding.UTF8,
                                                          Application.Json);

                using HttpResponseMessage httpResponseMessage = await httpClient.PostAsync(url, metricRequestJson);

                success = httpResponseMessage.IsSuccessStatusCode;
                retries--;
            }
        } catch (Exception ex) {
            StringBuilder errMsgBuilder = new();
            errMsgBuilder.Append($"An exception occurred when attempting to send MonIn count request for resource {_resource} ");
            errMsgBuilder.Append($"with name {metricName} and value {metricValue} to url {url}. Exception: {ex.Message}");
            _logger.LogError(errMsgBuilder.ToString());
        }
    }

    public async void PostAverage(string metricName, double metricValue) {
        string url = _baseUrl + "average";

        StringBuilder logMsgBuilder = new();
        logMsgBuilder.Append($"Attempting to send MonIn average request for resource {_resource} ");
        logMsgBuilder.Append($"with name {metricName} and value {metricValue} to url {url}");
        _logger.LogInformation(logMsgBuilder.ToString());

        try {
            bool success = false;
            int retries = _retryLimit;
            while (!success && retries > 0) {
                Task.Delay(TimeSpan.FromSeconds((_retryLimit - retries) * _backoffInSeconds)).Wait();

                HttpClient httpClient = _httpClientFactory.CreateClient();

                MonInMetricRequest metricRequest = new MonInMetricRequest() {
                    resource = _resource,
                    dateTime = DateTime.Now,
                    metricName = metricName,
                    metricValue = metricValue
                };

                StringContent metricRequestJson = new StringContent(JsonSerializer.Serialize(metricRequest),
                                                          Encoding.UTF8,
                                                          Application.Json);

                using HttpResponseMessage httpResponseMessage = await httpClient.PostAsync(url, metricRequestJson);

                success = httpResponseMessage.IsSuccessStatusCode;
                retries--;
            }
        } catch (Exception ex) {
            StringBuilder errMsgBuilder = new();
            errMsgBuilder.Append($"An exception occurred when attempting to send MonIn average request for resource {_resource} ");
            errMsgBuilder.Append($"with name {metricName} and value {metricValue} to url {url}. Exception: {ex.Message}");
            _logger.LogError(errMsgBuilder.ToString());
        }
    }
}