using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json;
using System.Threading;
using System.Threading.Tasks;
using FinlyticCore.Dtos;
using FinlyticCore.Dtos.News;
using FinlyticCore.Dtos.Sentiment;
using FinlyticCore.Dtos.Settings;
using FinlyticCore.Models;
using FinlyticCore.Services;
using FinlyticCore.Util;
using FinlyticSentiment.Entities;
using FinlyticSentiment.Services;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;

namespace FinlyticSentiment.Util;

/// <summary>
/// Managed MQTT client for sentiment evaluations and RPC queries.
/// </summary>
public class SentimentMqttClient : ManagedMqttClient, IHostedService
{
    private readonly ILogger<SentimentMqttClient> _logger;
    private readonly IConfiguration _configuration;
    private readonly IServiceScopeFactory _scopeFactory;

    public SentimentMqttClient(
        ILogger<SentimentMqttClient> logger,
        IConfiguration configuration,
        IServiceScopeFactory scopeFactory) : base(logger)
    {
        _logger = logger;
        _configuration = configuration;
        _scopeFactory = scopeFactory;
    }

    /// <summary>
    /// Starts the MQTT client and connects to the broker.
    /// </summary>
    public async Task StartAsync(CancellationToken cancellationToken)
    {
        var config = MqttConfiguration.FromConfiguration(_configuration, "FinlyticSentiment");

        _logger.LogInformation("Starting Sentiment MQTT client. Host: {Host}, ClientId: {ClientId}", config.Host, config.ClientId);
        await ConnectAsync(config);
    }

    /// <summary>
    /// Stops the MQTT client and disconnects from the broker.
    /// </summary>
    public async Task StopAsync(CancellationToken cancellationToken)
    {
        _logger.LogInformation("Stopping Sentiment MQTT client and disconnecting.");
        await DisconnectAsync();
    }

    /// <summary>
    /// Event triggered when a real-time article is broadcasted on services/news/completed.
    /// </summary>
    public event Func<NewsArticleDto, Task>? OnArticleReceived;

    /// <inheritdoc />
    protected override async Task OnConnectedAsync()
    {
        _logger.LogInformation("Sentiment MQTT client connected. Registering RPC topic subscriptions...");

        await SubscribeAsync(MqttTopics.ResponseWildcard);
        await SubscribeRpcAsync<GetSentimentByIsinRequest, IsinSentimentSummaryDto?>(MqttTopics.RequestFilter(MqttTopics.Channels.SentimentGetIsin), HandleSentimentGetIsinRpcAsync);
        await SubscribeRpcAsync<GetSectorSentimentRequest, SectorSentimentSummaryDto?>(MqttTopics.RequestFilter(MqttTopics.Channels.SentimentGetSector), HandleSentimentGetSectorRpcAsync);
        await SubscribeRpcAsync<ArticleRequest, IsinAnalysisEntry?>(MqttTopics.RequestFilter(MqttTopics.Channels.SentimentGetArticle), HandleSentimentGetArticleRpcAsync);
        await SubscribeRpcAsync<PaginatedRequest, List<CompanySentimentSummaryEntity>>(MqttTopics.RequestFilter(MqttTopics.Channels.SentimentGetAll), HandleSentimentGetAllRpcAsync);
        await SubscribeRpcAsync<JsonElement, IsinAnalysisEntry?>(MqttTopics.RequestFilter(MqttTopics.Channels.SentimentAnalyze), HandleSentimentAnalyzeRpcAsync);
        await SubscribeRpcAsync<object, List<DynamicSettingDto>>(MqttTopics.RequestFilter(MqttTopics.Channels.SentimentSettingsGetAll), HandleSettingsGetAllRpcAsync);
        await SubscribeRpcAsync<Dictionary<string, object?>, List<DynamicSettingDto>>(MqttTopics.RequestFilter(MqttTopics.Channels.SentimentSettingsUpdate), HandleSettingsUpdateRpcAsync);
        await SubscribeAsync<object>(MqttTopics.RequestFilter(MqttTopics.Channels.HealthPing), HandleHealthPingRpcAsync);
        await SubscribeAsync<NewsArticleDto>(MqttTopics.NewsCompleted, HandleNewsCompletedBroadcastAsync);

        FinlyticCore.Services.FinlyticLogBroadcaster.OnLogPublished = async (logDto) =>
        {
            if (IsConnected && string.Equals(logDto.ServiceName, "FinlyticSentiment", StringComparison.OrdinalIgnoreCase))
            {
                await PublishAsync(MqttTopics.Logs("FinlyticSentiment"), logDto);
            }
        };
    }

    /// <summary>
    /// Requests pending news articles from FinlyticNews via MQTT RPC.
    /// </summary>
    public async Task<List<NewsArticleDto>> GetPendingArticlesAsync(int limit = 10)
    {
        try
        {
            var req = new LimitRequest(limit);
            var response = await SendRpcRequestAsync<List<NewsArticleDto>, LimitRequest>(
                MqttTopics.Channels.NewsGetPending,
                req,
                TimeSpan.FromSeconds(5)
            );
            return response ?? [];
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Failed to retrieve pending articles from FinlyticNews via news_GetPending");
            return [];
        }
    }

    /// <summary>
    /// Updates the article processing status in FinlyticNews.
    /// </summary>
    public async Task UpdateArticleStatusAsync(Guid articleId, string status)
    {
        try
        {
            var req = new UpdateNewsStatusRequest(articleId, status);
            await SendRpcRequestAsync<UpdateNewsStatusResponse, UpdateNewsStatusRequest>(
                MqttTopics.Channels.NewsUpdateStatus,
                req,
                TimeSpan.FromSeconds(5)
            );
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Failed to update article status for {ArticleId} to '{Status}'", articleId, status);
        }
    }

    /// <summary>
    /// Broadcasts an updated sentiment result for an asset over MQTT.
    /// </summary>
    public async Task BroadcastSentimentResultAsync(string isin, IsinSentimentSummaryDto summary)
    {
        if (string.IsNullOrWhiteSpace(isin) || summary == null) return;
        await PublishAsync(MqttTopics.SentimentStream(isin), summary);
    }

    private async Task<IsinSentimentSummaryDto?> HandleSentimentGetIsinRpcAsync(GetSentimentByIsinRequest? req, string correlationId)
    {
        var targetIsin = req?.Isin;
        if (string.IsNullOrWhiteSpace(targetIsin)) return null;

        using var scope = _scopeFactory.CreateScope();
        var finlyticLogger = scope.ServiceProvider.GetRequiredService<IFinlyticLogger<SentimentMqttClient>>();
        var dbService = scope.ServiceProvider.GetRequiredService<ISentimentDbService>();

        await finlyticLogger.LogInfoAsync(SettingKeys.SentimentChannel, "[SentimentMqttClient] Processing RPC sentiment_GetIsin for {Isin} [CorrelationId: {CorrelationId}]", targetIsin, correlationId);
        return await dbService.GetIsinSummaryDtoAsync(targetIsin);
    }

    private async Task<SectorSentimentSummaryDto?> HandleSentimentGetSectorRpcAsync(GetSectorSentimentRequest? req, string correlationId)
    {
        var sector = req?.Sector;
        if (string.IsNullOrWhiteSpace(sector)) return null;

        using var scope = _scopeFactory.CreateScope();
        var finlyticLogger = scope.ServiceProvider.GetRequiredService<IFinlyticLogger<SentimentMqttClient>>();
        var dbService = scope.ServiceProvider.GetRequiredService<ISentimentDbService>();

        await finlyticLogger.LogInfoAsync(SettingKeys.SentimentChannel, "[SentimentMqttClient] Processing RPC sentiment_GetSector for {Sector} [CorrelationId: {CorrelationId}]", sector, correlationId);
        return await dbService.GetSectorSentimentAsync(sector);
    }

    private async Task<IsinAnalysisEntry?> HandleSentimentGetArticleRpcAsync(ArticleRequest? req, string correlationId)
    {
        var targetId = req?.ArticleId ?? req?.Id;
        if (string.IsNullOrWhiteSpace(targetId) || !Guid.TryParse(targetId, out var articleId))
            return null;

        using var scope = _scopeFactory.CreateScope();
        var finlyticLogger = scope.ServiceProvider.GetRequiredService<IFinlyticLogger<SentimentMqttClient>>();
        var dbService = scope.ServiceProvider.GetRequiredService<ISentimentDbService>();

        await finlyticLogger.LogInfoAsync(SettingKeys.SentimentChannel, "[SentimentMqttClient] Processing RPC sentiment_GetArticle for {ArticleId} [CorrelationId: {CorrelationId}]", articleId, correlationId);
        return await dbService.GetArticleSentimentEntryAsync(articleId);
    }

    private async Task<List<CompanySentimentSummaryEntity>> HandleSentimentGetAllRpcAsync(PaginatedRequest? req, string correlationId)
    {
        using var scope = _scopeFactory.CreateScope();
        var finlyticLogger = scope.ServiceProvider.GetRequiredService<IFinlyticLogger<SentimentMqttClient>>();
        var dbService = scope.ServiceProvider.GetRequiredService<ISentimentDbService>();

        await finlyticLogger.LogInfoAsync(SettingKeys.SentimentChannel, "[SentimentMqttClient] Processing RPC sentiment_GetAll [CorrelationId: {CorrelationId}]", correlationId);
        return await dbService.GetAllCompanySentimentsAsync(req?.Limit ?? 50, req?.Offset ?? 0);
    }

    private async Task<IsinAnalysisEntry?> HandleSentimentAnalyzeRpcAsync(JsonElement rawPayload, string correlationId)
    {
        if (rawPayload.ValueKind == JsonValueKind.Undefined || rawPayload.ValueKind == JsonValueKind.Null) return null;

        using var scope = _scopeFactory.CreateScope();
        var finlyticLogger = scope.ServiceProvider.GetRequiredService<IFinlyticLogger<SentimentMqttClient>>();
        var analyzer = scope.ServiceProvider.GetRequiredService<IFinBertAnalyzerService>();
        var dbService = scope.ServiceProvider.GetRequiredService<ISentimentDbService>();

        NewsArticleDto? article = null;
        try
        {
            var rawText = rawPayload.GetRawText();
            if (rawPayload.TryGetProperty("contentRaw", out _) || rawPayload.TryGetProperty("sourceUrl", out _))
            {
                article = JsonSerializer.Deserialize<NewsArticleDto>(rawText);
            }
            else if (rawPayload.TryGetProperty("articleId", out var articleIdProp))
            {
                var articleIdStr = articleIdProp.GetString();
                if (Guid.TryParse(articleIdStr, out var parsedGuid))
                {
                    article = await SendRpcRequestAsync<NewsArticleDto, ArticleRequest>(
                        MqttTopics.Channels.NewsGetById,
                        new ArticleRequest(articleIdStr, articleIdStr),
                        TimeSpan.FromSeconds(5)
                    );
                }
            }
        }
        catch (Exception ex)
        {
            await finlyticLogger.LogWarningAsync(SettingKeys.SentimentChannel, ex, "[SentimentMqttClient] Failed to deserialize payload in sentiment_Analyze");
        }

        if (article == null || article.Id == Guid.Empty) return null;

        await finlyticLogger.LogInfoAsync(SettingKeys.SentimentChannel, "[SentimentMqttClient] Processing RPC sentiment_Analyze for {ArticleId} [CorrelationId: {CorrelationId}]", article.Id, correlationId);
        var result = await analyzer.AnalyzeArticleAsync(article);

        if (result != null && article.MatchedAssets != null)
        {
            foreach (var asset in article.MatchedAssets)
            {
                if (string.IsNullOrWhiteSpace(asset.Isin)) continue;
                await dbService.SaveArticleSentimentAsync(article.Id, asset.Isin, asset.Name, null, article.PublishedAt, result);
            }

            return await dbService.GetArticleSentimentEntryAsync(article.Id);
        }

        return null;
    }

    private async Task<List<DynamicSettingDto>> HandleSettingsGetAllRpcAsync(object? _, string correlationId)
    {
        using var scope = _scopeFactory.CreateScope();
        var finlyticLogger = scope.ServiceProvider.GetRequiredService<IFinlyticLogger<SentimentMqttClient>>();
        var settingsService = scope.ServiceProvider.GetRequiredService<ISettingsService>();

        await finlyticLogger.LogInfoAsync(SettingKeys.MqttChannel, "[FinlyticSentiment] [Settings_GetAll] Retrieving service dynamic settings [CorrelationId: {CorrelationId}]", correlationId);
        return await settingsService.GetAllRegisteredSettingsAsync(new[] { typeof(SettingKeys) });
    }

    private async Task<List<DynamicSettingDto>> HandleSettingsUpdateRpcAsync(Dictionary<string, object?>? updates, string correlationId)
    {
        using var scope = _scopeFactory.CreateScope();
        var finlyticLogger = scope.ServiceProvider.GetRequiredService<IFinlyticLogger<SentimentMqttClient>>();
        var settingsService = scope.ServiceProvider.GetRequiredService<ISettingsService>();

        await finlyticLogger.LogInfoAsync(SettingKeys.MqttChannel, "[FinlyticSentiment] [Settings_Update] Processing settings update RPC [CorrelationId: {CorrelationId}]", correlationId);
        if (updates != null && updates.Count > 0)
        {
            await settingsService.UpdateSettingsAsync(updates);
            await finlyticLogger.LogInfoAsync(SettingKeys.MqttChannel, "[FinlyticSentiment] [Settings_Update] Successfully updated {Count} settings in database and cache.", updates.Count);
        }
        return await settingsService.GetAllRegisteredSettingsAsync(new[] { typeof(SettingKeys) });
    }

    private async Task HandleHealthPingRpcAsync(object? _, string topic, string correlationId)
    {
        if (topic.Contains("FinlyticSentiment", StringComparison.OrdinalIgnoreCase))
        {
            string respTopic = MqttTopics.ResponseTopic(MqttTopics.Channels.HealthPing, correlationId);
            await PublishAsync(respTopic, new ServiceHealthResponse("FinlyticSentiment", "Online", DateTime.UtcNow, "Connected"));

            using var scope = _scopeFactory.CreateScope();
            var finlyticLogger = scope.ServiceProvider.GetRequiredService<IFinlyticLogger<SentimentMqttClient>>();
            await finlyticLogger.LogInfoAsync(SettingKeys.HealthPingChannel, "Responded to live health_Ping RPC request [CorrelationId: {CorrelationId}].", correlationId);
        }
    }

    private async Task HandleNewsCompletedBroadcastAsync(NewsArticleDto? article, string topic, string correlationId)
    {
        if (article != null && OnArticleReceived != null)
        {
            await OnArticleReceived.Invoke(article);
        }
    }
}