using FrameworkDAL.DTO.MessageHub.MessageHubGenerator;
using GB5Shared.DTO.Framework.Login;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using Newtonsoft.Json;
using System;
using System.Net.Http;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace FrameworkBLL.MessageHub.MessageHubPlatforms
{
    /// <summary>
    /// Telegram Platform implementation for MessageHub
    /// Handles sending both Template and Conversation messages
    /// </summary>
    public class TelegramPlatform : IMessageHubPlatform.ITelegramPlatform
    {
        private readonly IHttpClientFactory _httpClientFactory;
        private readonly MessageHubSettings _settings;
        private readonly ILogger<TelegramPlatform> _logger;

        public TelegramPlatform(
            IHttpClientFactory httpClientFactory,
            IOptions<MessageHubSettings> settings,
            ILogger<TelegramPlatform> logger)
        {
            _httpClientFactory = httpClientFactory ?? throw new ArgumentNullException(nameof(httpClientFactory));
            _settings = settings?.Value ?? throw new ArgumentNullException(nameof(settings));
            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
        }

        // ==========================================================
        // ✅ TEMPLATE MESSAGE
        // ==========================================================
        /// <summary>
        /// Sends a Telegram Template message via MessageHub
        /// </summary>
        public async Task<MessageHubResponseDTO> SendTelegramTemplate(
            MessageHubDTO dto,
            LoginDTO login,
            CancellationToken ct)
        {
            if (dto == null) return Fail("Template DTO cannot be null");
            if (login == null) return Fail("Login info missing");

            var chatId = string.IsNullOrWhiteSpace(dto.Recipient)
                ? _settings.Telegram.DefaultRecipient
                : dto.Recipient;

            if (string.IsNullOrWhiteSpace(chatId))
                return Fail("Telegram ChatId is missing");

            var payload = new
            {
                chat_id = chatId,
                text = $"📢 TEMPLATE MESSAGE\n\n{dto.MessageText}\n\nSent by: {login.UserName}",
                parse_mode = "HTML"
            };

            try
            {
                var client = _httpClientFactory.CreateClient();
                var requestUrl =
                    $"{(_settings.Telegram.BaseUrl ?? "https://api.telegram.org")}/bot{_settings.Telegram.BotToken}/sendMessage";

                _logger.LogInformation(
                    "Sending Telegram Template | ChatId={ChatId} | ActionId={ActionId}",
                    chatId,
                    dto.ActionId);

                var response = await client.PostAsync(
                    requestUrl,
                    new StringContent(JsonConvert.SerializeObject(payload), Encoding.UTF8, "application/json"),
                    ct);

                var responseContent = await response.Content.ReadAsStringAsync(ct);

                return new MessageHubResponseDTO
                {
                    Success = response.IsSuccessStatusCode,
                    Message = response.IsSuccessStatusCode
                        ? "Telegram Template message sent successfully"
                        : $"Telegram Template message failed: {response.StatusCode}",
                    ResponseData = responseContent
                };
            }
            catch (OperationCanceledException)
            {
                _logger.LogWarning("Telegram Template send cancelled | ChatId={ChatId}", chatId);
                return Fail("Telegram request cancelled");
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Telegram Template send failed | ChatId={ChatId}", chatId);
                return Fail($"Telegram error: {ex.Message}");
            }
        }

        // ==========================================================
        // ✅ CONVERSATION MESSAGE
        // ==========================================================
        /// <summary>
        /// Sends a Telegram Conversation message via MessageHub
        /// </summary>
        public async Task<MessageHubResponseDTO> SendTelegramConversation(
            MessageHubDTO dto,
            LoginDTO login,
            CancellationToken ct)
        {
            if (dto == null)
                return Fail("MessageHubDTO cannot be null");

            if (login == null)
                return Fail("Login context is required");

            if (string.IsNullOrWhiteSpace(_settings.Telegram.BotToken))
                return Fail("Telegram BotToken is missing in configuration");

            var chatId = !string.IsNullOrWhiteSpace(dto.Recipient)
                ? dto.Recipient
                : _settings.Telegram.DefaultRecipient;

            if (string.IsNullOrWhiteSpace(chatId))
                return Fail("Telegram ChatId is missing");

            var messageText = !string.IsNullOrWhiteSpace(dto.MessageText)
                ? dto.MessageText
                : dto.TextMessage;

            if (string.IsNullOrWhiteSpace(messageText) &&
                string.IsNullOrWhiteSpace(dto.PayloadJson))
                return Fail("Telegram message content is empty");

            object payload;

            // Use pre-formed JSON payload if provided
            if (!string.IsNullOrWhiteSpace(dto.PayloadJson))
            {
                payload = JsonConvert.DeserializeObject(dto.PayloadJson)!;
            }
            else
            {
                payload = new
                {
                    chat_id = chatId,
                    text = messageText,
                    parse_mode = "HTML"
                };
            }

            try
            {
                var client = _httpClientFactory.CreateClient();
                var requestUrl =
                    $"{(_settings.Telegram.BaseUrl ?? "https://api.telegram.org")}/bot{_settings.Telegram.BotToken}/sendMessage";

                _logger.LogInformation(
                    "Sending Telegram Conversation | ChatId={ChatId} | ActionId={ActionId}",
                    chatId,
                    dto.ActionId);

                var response = await client.PostAsync(
                    requestUrl,
                    new StringContent(JsonConvert.SerializeObject(payload), Encoding.UTF8, "application/json"),
                    ct);

                var responseContent = await response.Content.ReadAsStringAsync(ct);

                _logger.LogInformation(
                    "Telegram response | Success={Success} | StatusCode={StatusCode} | ChatId={ChatId}",
                    response.IsSuccessStatusCode,
                    response.StatusCode,
                    chatId);

                return new MessageHubResponseDTO
                {
                    Success = response.IsSuccessStatusCode,
                    Message = response.IsSuccessStatusCode
                        ? "Telegram message sent successfully"
                        : $"Telegram message failed: {response.StatusCode}",
                    ResponseData = responseContent
                };
            }
            catch (OperationCanceledException)
            {
                _logger.LogWarning("Telegram send cancelled | ChatId={ChatId}", chatId);
                return Fail("Telegram request cancelled");
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Telegram send failed | ChatId={ChatId}", chatId);
                return Fail($"Telegram error: {ex.Message}");
            }
        }

        // ==========================================================
        // PRIVATE HELPER
        // ==========================================================
        private static MessageHubResponseDTO Fail(string reason)
            => new() { Success = false, Message = reason };
    }
}