using AutoMapper;
using DigitalData.Core.DTO;
using EnvelopeGenerator.Application.Contracts.Services;
using EnvelopeGenerator.Application.Contracts.SQLExecutor;
using EnvelopeGenerator.Application.DTOs.Receiver;
using EnvelopeGenerator.Application.EnvelopeReceivers.Commands.Create;
using EnvelopeGenerator.Application.EnvelopeReceivers.Queries.Read;
using EnvelopeGenerator.Application.Envelopes.Queries.ReceiverName;
using EnvelopeGenerator.Domain.Entities;
using EnvelopeGenerator.GeneratorAPI.Models;
using MediatR;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Data.SqlClient;
using Microsoft.Extensions.Options;
using System.Data;
using System.Threading.Channels;

namespace EnvelopeGenerator.GeneratorAPI.Controllers;

/// <summary>
/// Controller für die Verwaltung von Umschlagempfängern.
/// </summary>
/// <remarks>
/// Dieser Controller bietet Endpunkte für das Abrufen und Verwalten von Umschlagempfängerdaten.
/// </remarks>
[Route("api/[controller]")]
[Authorize]
[ApiController]
public class EnvelopeReceiverController : ControllerBase
{
    private readonly ILogger<EnvelopeReceiverController> _logger;

    private readonly IEnvelopeReceiverService _erService;

    private readonly IMediator _mediator;

    private readonly IMapper _mapper;

    private readonly IEnvelopeExecutor _envelopeExecutor;

    private readonly IEnvelopeReceiverExecutor _erExecutor;

    private readonly IDocumentExecutor _documentExecutor;

    private readonly string _cnnStr;

    /// <summary>
    /// Konstruktor für den EnvelopeReceiverController.
    /// </summary>
    /// <param name="logger">Logger-Instanz zur Protokollierung von Informationen und Fehlern.</param>
    /// <param name="envelopeReceiverService">Service zur Verwaltung von Umschlagempfängern.</param>
    /// <param name="mediator">Mediator-Instanz zur Verarbeitung von Befehlen und Abfragen.</param>
    /// <param name="mapper"></param>
    /// <param name="envelopeExecutor"></param>
    /// <param name="erExecutor"></param>
    public EnvelopeReceiverController(ILogger<EnvelopeReceiverController> logger, IEnvelopeReceiverService envelopeReceiverService, IMediator mediator, IMapper mapper, IEnvelopeExecutor envelopeExecutor, IEnvelopeReceiverExecutor erExecutor, IDocumentExecutor documentExecutor, IOptions<ConnectionString> csOpt)
    {
        _logger = logger;
        _erService = envelopeReceiverService;
        _mediator = mediator;
        _mapper = mapper;
        _envelopeExecutor = envelopeExecutor;
        _erExecutor = erExecutor;
        _documentExecutor = documentExecutor;
        _cnnStr = csOpt.Value.Value;
    }

    /// <summary>
    /// Ruft eine Liste von Umschlagempfängern basierend auf den angegebenen Abfrageparametern ab.
    /// </summary>
    /// <param name="envelopeReceiver">Die Abfrageparameter für die Filterung von Umschlagempfängern.</param>
    /// <returns>Eine HTTP-Antwort mit der Liste der gefundenen Umschlagempfänger oder einem Fehlerstatus.</returns>
    /// <remarks>
    /// Dieser Endpunkt ermöglicht es, Umschlagempfänger basierend auf dem Benutzernamen und optionalen Statusfiltern abzurufen.
    /// Wenn der Benutzername nicht ermittelt werden kann, wird ein Serverfehler zurückgegeben.
    /// </remarks>
    /// <response code="200">Die Liste der Umschlagempfänger wurde erfolgreich abgerufen.</response>
    /// <response code="401">Wenn kein autorisierter Token vorhanden ist</response>
    /// <response code="500">Ein unerwarteter Fehler ist aufgetreten.</response>
    [Authorize]
    [HttpGet]
    public async Task<IActionResult> GetEnvelopeReceiver([FromQuery] ReadEnvelopeReceiverQuery envelopeReceiver)
    {
        try
        {
            var username = User.GetUsername();

            if (username is null)
            {
                _logger.LogError(@"Envelope Receiver dto cannot be sent because username claim is null. Potential authentication and authorization error. The value of other claims are [id: {id}], [username: {username}], [name: {name}], [prename: {prename}], [email: {email}].",
                    User.GetId(), User.GetUsername(), User.GetName(), User.GetPrename(), User.GetEmail());
                return StatusCode(StatusCodes.Status500InternalServerError);
            }

            return await _erService.ReadByUsernameAsync(
                username: username,
                min_status: envelopeReceiver.Status?.Min,
                max_status:envelopeReceiver.Status?.Max,
                envelopeQuery: envelopeReceiver.Envelope,
                receiverQuery: envelopeReceiver.Receiver,
                ignore_statuses: envelopeReceiver.Status?.Ignore ?? Array.Empty<int>())
                .ThenAsync(
                    Success: Ok,
                    Fail: IActionResult (msg, ntc) =>
                    {
                        _logger.LogNotice(ntc);
                        return StatusCode(StatusCodes.Status500InternalServerError, msg);
                    });
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "An unexpected error occurred. {message}", ex.Message);
            return new StatusCodeResult(StatusCodes.Status500InternalServerError);
        }
    }

    /// <summary>
    /// Ruft den Namen des zuletzt verwendeten Empfängers basierend auf der angegebenen E-Mail-Adresse ab.
    /// </summary>
    /// <param name="receiverName">Die Abfrage, die die E-Mail-Adresse des Empfängers enthält.</param>
    /// <returns>Eine HTTP-Antwort mit dem Namen des Empfängers oder einem Fehlerstatus.</returns>
    /// <remarks>
    /// Dieser Endpunkt ermöglicht es, den Namen des zuletzt verwendeten Empfängers basierend auf der E-Mail-Adresse abzurufen.
    /// </remarks>
    /// <response code="200">Der Name des Empfängers wurde erfolgreich abgerufen.</response>
    /// <response code="401">Wenn kein autorisierter Token vorhanden ist</response>
    /// <response code="404">Kein Empfänger gefunden.</response>
    /// <response code="500">Ein unerwarteter Fehler ist aufgetreten.</response>
    [Authorize]
    [HttpGet("salute")]
    public async Task<IActionResult> GetReceiverName([FromQuery] ReadReceiverNameQuery receiverName)
    {
        try
        {
            return await _erService.ReadLastUsedReceiverNameByMail(receiverName.EmailAddress).ThenAsync(
                            Success: res => res is null ? Ok(string.Empty) : Ok(res),
                            Fail: IActionResult (msg, ntc) =>
                            {
                                if (ntc.HasFlag(Flag.NotFound))
                                    return NotFound();

                                _logger.LogNotice(ntc);
                                return StatusCode(StatusCodes.Status500InternalServerError);
                            });
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "{message}", ex.Message);
            return StatusCode(StatusCodes.Status500InternalServerError);
        }
    }

    /// <summary>
    /// Datenübertragungsobjekt mit Informationen zu Umschlägen, Empfängern und Unterschriften.
    /// </summary>
    /// <param name="request"></param>
    /// <returns>HTTP-Antwort</returns>
    /// <remarks>
    /// Sample request:
    ///
    ///     POST /api/envelope
    ///     {
    ///        "title": "Vertragsdokument",
    ///        "message": "Bitte unterschreiben Sie dieses Dokument.",
    ///        "document": {
    ///            "dataAsBase64": "dGVzdC1iYXNlNjQtZGF0YQ=="  
    ///        },
    ///        "receivers": [
    ///            {
    ///                "emailAddress": "example@example.com",
    ///                "signatures": [
    ///                    {
    ///                        "x": 100,
    ///                        "y": 200,
    ///                        "page": 1
    ///                    }
    ///                ],
    ///                "name": "Max Mustermann",
    ///                "phoneNumber": "+49123456789"
    ///            }
    ///        ],
    ///        "tfaEnabled": false
    ///     }
    ///
    /// </remarks>
    /// <response code="202">Envelope-Erstellung und Sendeprozessbefehl erfolgreich</response>
    /// <response code="400">Wenn ein Fehler im HTTP-Body auftritt</response>
    /// <response code="401">Wenn kein autorisierter Token vorhanden ist</response>
    /// <response code="500">Es handelt sich um einen unerwarteten Fehler. Die Protokolle sollten überprüft werden.</response>
    [Authorize]
    [HttpPost]
    public async Task<IActionResult> CreateAsync([FromBody] CreateEnvelopeReceiverCommand request)
    {
        try
        {
            CancellationToken cancel = default;
            int userId = User.GetId();

            #region Create Envelope
            var envelope = await _envelopeExecutor.CreateEnvelopeAsync(userId, request.Title, request.Message, request.TFAEnabled, cancel);
            #endregion

            #region Add receivers
            List<EnvelopeReceiver> sentRecipients = new();
            List<ReceiverGetOrCreateCommand> unsentRecipients = new();

            foreach (var receiver in request.Receivers)
            {
                var envelopeReceiver = await _erExecutor.AddEnvelopeReceiverAsync(envelope.Uuid, receiver.EmailAddress, receiver.Salution, receiver.PhoneNumber, cancel);

                if (envelopeReceiver is null)
                    unsentRecipients.Add(receiver);
                else
                    sentRecipients.Add(envelopeReceiver);
            }

            var res = _mapper.Map<CreateEnvelopeReceiverResponse>(envelope);
            res.UnsentRecipients = unsentRecipients;
            res.SentRecipients = _mapper.Map<IEnumerable<ReceiverReadDto>>(sentRecipients);
            #endregion

            #region Add document
            if(request.Document.DataAsBase64 is null)
                if (request.Document.DataAsByte is null)
                    return BadRequest("No document data is found");
                else
                    request.Document.DataAsBase64 = Convert.ToBase64String(request.Document.DataAsByte);
            else if (request.Document.DataAsByte is not null)
                return BadRequest("Document data cannot be assigned as both byte data and base64 string.");
            else if (!IsBase64String(request.Document.DataAsBase64))
                return BadRequest("Document data is not a base64 string");

            var document = await _documentExecutor.CreateDocumentAsync(request.Document.DataAsBase64, envelope.Uuid, cancel);

            if(document is null)
                return StatusCode(StatusCodes.Status500InternalServerError, "Document creation is failed.");
            #endregion

            #region Add document element
            string sql = @"
                USE [DD_ECM]

                DECLARE @OUT_SUCCESS bit;

                EXEC [dbo].[PRSIG_API_ADD_DOC_RECEIVER_ELEM]
                    @DOC_ID = @DOC_ID,
                    @RECEIVER_ID = @RECEIVER_ID,
                    @POSITION_X = @POSITION_X,
                    @POSITION_Y = @POSITION_Y,
                    @PAGE = @PAGE,
                    @OUT_SUCCESS = @OUT_SUCCESS OUTPUT;

                SELECT @OUT_SUCCESS as [@OUT_SUCCESS];";

            foreach(var rcv in res.SentRecipients)
                foreach(var sign in request.Receivers.Where(r => r.EmailAddress == rcv.EmailAddress).FirstOrDefault()?.Signatures ?? Array.Empty<Signature>())
                {
                    using (SqlConnection conn = new(_cnnStr))
                    {
                        conn.Open();

                        using SqlCommand cmd = new SqlCommand(sql, conn);
                        cmd.CommandType = CommandType.Text;

                        cmd.Parameters.AddWithValue("@DOC_ID", document.Id);
                        cmd.Parameters.AddWithValue("@RECEIVER_ID", rcv.Id);
                        cmd.Parameters.AddWithValue("@POSITION_X", sign.X.ToString());
                        cmd.Parameters.AddWithValue("@POSITION_Y", sign.Y.ToString());
                        cmd.Parameters.AddWithValue("@PAGE", sign.Page.ToString());

                        using SqlDataReader reader = cmd.ExecuteReader();
                        if (reader.Read())
                        {
                            bool outSuccess = reader.GetBoolean(0);
                        }
                    }
                }
            #endregion

            #region Create history
            string connectionString = "Server=YOUR_SERVER;Database=YOUR_DATABASE;Trusted_Connection=True;";

            string sql_hist = @"
                USE [DD_ECM]

                DECLARE @OUT_SUCCESS bit;

                EXEC [dbo].[PRSIG_API_ADD_HISTORY_STATE]
                    @ENV_UID = @ENV_UID,
                    @STATUS_ID = @STATUS_ID,
                    @USER_ID = @USER_ID,
                    @OUT_SUCCESS = @OUT_SUCCESS OUTPUT;

                SELECT @OUT_SUCCESS as [@OUT_SUCCESS];";

            using (SqlConnection conn = new(connectionString))
            {
                conn.Open();

                using (SqlCommand cmd = new SqlCommand(sql_hist, conn))
                {
                    cmd.CommandType = CommandType.Text;

                    cmd.Parameters.AddWithValue("@ENV_UID", envelope.Uuid);
                    cmd.Parameters.AddWithValue("@STATUS_ID", 1003);
                    cmd.Parameters.AddWithValue("@USER_ID", userId);

                    using (SqlDataReader reader = cmd.ExecuteReader())
                    {
                        if (reader.Read())
                        {
                            bool outSuccess = reader.GetBoolean(0);
                        }
                    }
                }
            }
            #endregion

            return Ok(res);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "{Message}", ex.Message);
            return StatusCode(StatusCodes.Status500InternalServerError);
        }
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="input"></param>
    /// <returns></returns>
    public static bool IsBase64String(string input)
    {
        if (string.IsNullOrWhiteSpace(input))
            return false;

        try
        {
            Convert.FromBase64String(input);
            return true;
        }
        catch (FormatException)
        {
            return false;
        }
    }

}