using System.Data;
using System.IO;
using EnvelopeGenerator.Domain.Entities;
using iText.Kernel.Pdf;
using iText.Layout.Element;
using Microsoft.Data.SqlClient;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Logging.Abstractions;
using static EnvelopeGenerator.Jobs.FinalizeDocument.FinalizeDocumentExceptions;
using LayoutDocument = iText.Layout.Document;

namespace EnvelopeGenerator.Jobs.FinalizeDocument;

public class ReportCreator
{
    private readonly ILogger<ReportCreator> _logger;

    public ReportCreator() : this(NullLogger<ReportCreator>.Instance)
    {
    }

    public ReportCreator(ILogger<ReportCreator> logger)
    {
        _logger = logger;
    }

    public byte[] CreateReport(SqlConnection connection, Envelope envelope)
    {
        try
        {
            var reportItems = LoadReportItems(connection, envelope.Id);
            using var stream = new MemoryStream();
            using var writer = new PdfWriter(stream);
            using var pdf = new PdfDocument(writer);
            using var document = new LayoutDocument(pdf);

            document.Add(new Paragraph("Envelope Finalization Report").SetFontSize(16));
            document.Add(new Paragraph($"Envelope Id: {envelope.Id}"));
            document.Add(new Paragraph($"UUID: {envelope.Uuid}"));
            document.Add(new Paragraph($"Title: {envelope.Title}"));
            document.Add(new Paragraph($"Subject: {envelope.Comment}"));
            document.Add(new Paragraph($"Generated: {DateTime.UtcNow:O}"));
            document.Add(new Paragraph(" "));

            var table = new Table(4).UseAllAvailableWidth();
            table.AddHeaderCell("Date");
            table.AddHeaderCell("Status");
            table.AddHeaderCell("User");
            table.AddHeaderCell("EnvelopeId");

            foreach (var item in reportItems.OrderByDescending(r => r.ItemDate))
            {
                table.AddCell(item.ItemDate.ToString("u"));
                table.AddCell(item.ItemStatus.ToString());
                table.AddCell(item.ItemUserReference);
                table.AddCell(item.EnvelopeId.ToString());
            }

            document.Add(table);
            document.Close();
            return stream.ToArray();
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Could not create report for envelope {EnvelopeId}", envelope.Id);
            throw new CreateReportException("Could not prepare report data", ex);
        }
    }

    private List<ReportItem> LoadReportItems(SqlConnection connection, int envelopeId)
    {
        const string sql = "SELECT ENVELOPE_ID, POS_WHEN, POS_STATUS, POS_WHO FROM VWSIG_ENVELOPE_REPORT WHERE ENVELOPE_ID = @EnvelopeId";
        var result = new List<ReportItem>();

        using var command = new SqlCommand(sql, connection);
        command.Parameters.AddWithValue("@EnvelopeId", envelopeId);
        using var reader = command.ExecuteReader();
        while (reader.Read())
        {
            result.Add(new ReportItem
            {
                EnvelopeId = reader.GetInt32(0),
                ItemDate = reader.IsDBNull(1) ? DateTime.MinValue : reader.GetDateTime(1),
                ItemStatus = reader.IsDBNull(2) ? default : (EnvelopeGenerator.Domain.Constants.EnvelopeStatus)reader.GetInt32(2),
                ItemUserReference = reader.IsDBNull(3) ? string.Empty : reader.GetString(3)
            });
        }

        return result;
    }
}