using System.Data;
using System.IO;
using DigitalData.Modules.Base;
using DigitalData.Modules.Logging;
using EnvelopeGenerator.Domain.Constants;
using EnvelopeGenerator.Domain.Entities;
using EnvelopeGenerator.ServiceHost.Exceptions;
using EnvelopeGenerator.ServiceHost.Jobs;

namespace EnvelopeGenerator.ServiceHost.Jobs.FinalizeDocument;

public class ReportCreator : BaseClass
{
    private Envelope? _envelope;
    private readonly ReportModel _reportModel;

    public ReportCreator(LogConfig logConfig, State state) : base(logConfig)
    {
        _reportModel = new ReportModel(state);
    }

    public byte[] CreateReport(Envelope envelope)
    {
        try
        {
            Logger.LogDebug("Loading report data..");
            var table = _reportModel.List(envelope.Id);
            var items = GetReportSource(table);

            _envelope = envelope;

            if (items.Count == 0)
            {
                throw new CreateReportException("No report data found!");
            }

            Logger.LogDebug("Creating report with [{0}] items..", items.Count);
            var buffer = DoCreateReport(items);
            Logger.LogDebug("Report created!");

            return buffer;
        }
        catch (Exception ex)
        {
            Logger.Error(ex);
            throw new CreateReportException("Could not prepare report data!", ex);
        }
    }

    private List<ReportItem> GetReportSource(DataTable dataTable)
    {
        Logger.LogDebug("Preparing report data");
        return dataTable.Rows
            .Cast<DataRow>()
            .Select(ToReportItem)
            .OrderByDescending(r => r.ItemDate)
            .ToList();
    }

    private byte[] DoCreateReport(List<ReportItem> reportItems)
    {
        var items = reportItems.Select(MergeEnvelope).ToList();
        var source = new ReportSource { Items = items };
        var report = new rptEnvelopeHistory { DataSource = source, DataMember = "Items" };

        Logger.LogDebug("Creating report in memory..");
        report.CreateDocument();

        Logger.LogDebug("Exporting report to stream..");
        using var stream = new MemoryStream();
        report.ExportToPdf(stream);

        Logger.LogDebug("Writing report to buffer..");
        return stream.ToArray();
    }

    private ReportItem MergeEnvelope(ReportItem item)
    {
        if (item.Envelope is null)
        {
            item.Envelope = _envelope;
        }

        return item;
    }

    private ReportItem ToReportItem(DataRow row)
    {
        try
        {
            return new ReportItem
            {
                EnvelopeId = row.ItemEx("ENVELOPE_ID", 0),
                EnvelopeTitle = row.ItemEx("HEAD_TITLE", string.Empty),
                EnvelopeSubject = row.ItemEx("HEAD_SUBJECT", string.Empty),
                ItemDate = row.ItemEx("POS_WHEN", DateTime.MinValue),
                ItemStatus = (EnvelopeStatus)row.ItemEx("POS_STATUS", 0),
                ItemUserReference = row.ItemEx("POS_WHO", string.Empty)
            };
        }
        catch (Exception ex)
        {
            Logger.Error(ex);
            throw new CreateReportException("Could not read data from database!", ex);
        }
    }
}