using AsbCloudDb.Model;
using ClosedXML.Excel;
using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Threading;
using System.Threading.Tasks;
using AsbCloudInfrastructure.Services.DetectOperations.Detectors;

namespace AsbCloudInfrastructure.Services.DetectOperations;

public class DetectedOperationExportService
{
	private readonly DetectorAbstract[] detectors = { new DetectorDrilling(), new DetectorSlipsTime() };

	private readonly IDictionary<int, string> domains = new Dictionary<int, string>
	{
		{ 1, "https://cloud.digitaldrilling.ru" },
		{ 2, "https://cloud.autodrilling.ru" }
	};

	private const int headerRowsCount = 1;

	private const string cellDepositName = "B1";
	private const string cellClusterName = "B2";
	private const string cellWellName = "B3";
	private const string cellDeltaDate = "H2";

	private const int columnOperationName = 1;
	private const int columnDateStart = 2;
	private const int columnDateEnd = 3;
	private const int columnDuration = 4;
	private const int columnDepthStart = 5;
	private const int columnDepthEnd = 6;
	private const int columnDeltaDepth = 7;
	private const int columnDepth = 8;
	private const int columnIdReasonOfEnd = 9;

	private readonly IAsbCloudDbContext dbContext;

	public DetectedOperationExportService(IAsbCloudDbContext dbContext)
	{
		this.dbContext = dbContext;
	}

	public async Task<Stream> ExportAsync(int idWell, int idDomain, CancellationToken cancellationToken)
	{
		var well = await dbContext.Wells
			.Include(w => w.Cluster)
			.ThenInclude(c => c.Deposit)
			.SingleOrDefaultAsync(w => w.Id == idWell, cancellationToken);

		if (well is null)
			throw new ArgumentNullException(nameof(well));

		if (!well.IdTelemetry.HasValue)
			throw new ArgumentNullException(nameof(well));

		var operations = await DetectOperationsAsync(well.IdTelemetry.Value, new DateTime(2023, 10, 14)
			.ToUtcDateTimeOffset(well.Timezone.Hours), cancellationToken);

		return await GenerateExcelFileStreamAsync(well, idDomain, operations, cancellationToken);
	}

	private async Task<Stream> GenerateExcelFileStreamAsync(Well well, int idDomain, IEnumerable<DetectedOperation> detectedOperations,
		CancellationToken cancellationToken)
	{
		using var excelTemplateStream = await GetExcelTemplateStreamAsync(cancellationToken);

		using var workbook = new XLWorkbook(excelTemplateStream, XLEventTracking.Disabled);

		await AddToWorkbookAsync(workbook, well, idDomain, detectedOperations, cancellationToken);

		MemoryStream memoryStream = new MemoryStream();
		workbook.SaveAs(memoryStream, new SaveOptions { });
		memoryStream.Seek(0, SeekOrigin.Begin);
		return memoryStream;
	}

	private async Task AddToWorkbookAsync(XLWorkbook workbook, Well well, int idDomain, IEnumerable<DetectedOperation> detectedOperations,
		CancellationToken cancellationToken)
	{
		const string sheetName = "Операции";

		if (!detectedOperations.Any())
			return;

		var sheet = workbook.Worksheets.FirstOrDefault(ws => ws.Name == sheetName)
					?? throw new FileFormatException($"Книга excel не содержит листа {sheetName}.");

		await AddToSheetAsync(sheet, well, idDomain, detectedOperations.OrderBy(x => x.DateStart).ThenBy(x => x.DepthStart).ToArray(),
			cancellationToken);
	}

	private async Task AddToSheetAsync(IXLWorksheet sheet, Well well, int idDomain, IList<DetectedOperation> detectedOperations,
		CancellationToken cancellationToken)
	{
		var wellOperationCategories = await dbContext.WellOperationCategories.ToListAsync(cancellationToken);

		sheet.Cell(cellDepositName).Value = well.Cluster.Deposit.Caption;
		sheet.Cell(cellClusterName).Value = well.Cluster.Caption;
		sheet.Cell(cellWellName).Value = well.Caption;
		sheet.Cell(cellDeltaDate).Value = detectedOperations.Max(o => o.DateEnd) - detectedOperations.Min(o => o.DateStart);

		var timeZoneWell = TimeSpan.FromHours(well.Timezone.Hours);

		for (int i = 0; i < detectedOperations.Count; i++)
		{
			var dateStart = detectedOperations[i].DateStart.ToOffset(timeZoneWell);
			var dateEnd = detectedOperations[i].DateEnd.ToOffset(timeZoneWell);

			var row = sheet.Row(5 + i + headerRowsCount);

			row.Cell(columnOperationName).Value = detectedOperations[i].IdCategory == 12000
				? "Бурение в слайде с осцилляцией"
				: wellOperationCategories.Single(o => o.Id == detectedOperations[i].IdCategory).Name;
			row.Cell(columnDateEnd).Value = dateEnd;
			row.Cell(columnDuration).Value = (dateEnd - dateStart).TotalMinutes;
			row.Cell(columnDepthStart).Value = detectedOperations[i].DepthStart;
			row.Cell(columnDepthEnd).Value = detectedOperations[i].DepthEnd;
			row.Cell(columnDepth).Value = detectedOperations[i].DepthEnd - detectedOperations[i].DepthStart;
			row.Cell(columnIdReasonOfEnd).Value = detectedOperations[i].IdReasonOfEnd;

			var link =
				$"{domains[idDomain]}/well/{well.Id}/telemetry/monitoring?end={Uri.EscapeDataString(dateStart.AddSeconds(3544).ToString("yyyy-MM-ddTHH:mm:ss.fff"))}&range=3600";

			row.Cell(columnDateStart).Value = dateStart;
			row.Cell(columnDateStart).SetHyperlink(new XLHyperlink(link));

			row.Cell(columnDeltaDepth).Value = i > 0 && i + 1 < detectedOperations.Count
				? detectedOperations[i].DepthStart - detectedOperations[i - 1].DepthEnd
				: 0;
		}
	}
	
	private async Task<Stream> GetExcelTemplateStreamAsync(CancellationToken cancellationToken)
	{
		string resourceName = Assembly.GetExecutingAssembly()
			.GetManifestResourceNames()
			.FirstOrDefault(n => n.EndsWith("DetectOperations.xlsx"))!;

		using var stream = Assembly.GetExecutingAssembly()
			.GetManifestResourceStream(resourceName)!;

		var memoryStream = new MemoryStream();
		await stream.CopyToAsync(memoryStream, cancellationToken);
		memoryStream.Position = 0;

		return memoryStream;
	}

	private async Task<IEnumerable<DetectedOperation>> DetectOperationsAsync(int idTelemetry, DateTimeOffset begin,
		CancellationToken token)
	{
		var query = dbContext.TelemetryDataSaub
			.AsNoTracking()
			.Where(d => d.IdTelemetry == idTelemetry)
			.Where(d => d.BlockPosition >= 0)
			.Select(d => new DetectableTelemetry
			{
				DateTime = d.DateTime,
				IdUser = d.IdUser,
				WellDepth = d.WellDepth,
				Pressure = d.Pressure,
				HookWeight = d.HookWeight,
				BlockPosition = d.BlockPosition,
				BitDepth = d.BitDepth,
				RotorSpeed = d.RotorSpeed,
			})
			.OrderBy(d => d.DateTime);

		var startDate = begin;
		var detectedOperations = new List<DetectedOperation>(8);
		DetectedOperation? lastDetectedOperation = null;
		const int minOperationLength = 5;
		const int maxDetectorsInterpolationFrameLength = 30;
		const int gap = maxDetectorsInterpolationFrameLength + minOperationLength;

		while (true)
		{
			var data = await query
				.Where(d => d.DateTime > startDate)
				.ToArrayAsync(token);

			if (data.Length < gap)
				break;

			var isDetected = false;
			var positionBegin = 0;
			var positionEnd = data.Length - gap;
			var step = 10;
			while (positionEnd > positionBegin)
			{
				step++;
				foreach (var detector in detectors)
				{
					if (!detector.TryDetect(idTelemetry, data, positionBegin, positionEnd, lastDetectedOperation, out var result))
						continue;
					
					detectedOperations.Add(result!.Operation);
					lastDetectedOperation = result.Operation;
					isDetected = true;
					step = 1;
					positionBegin = result.TelemetryEnd;
					break;
				}

				if (step > 20)
					step = 10;
				positionBegin += step;
			}

			if (isDetected)
				startDate = lastDetectedOperation!.DateEnd;
			else
				startDate = data[positionEnd].DateTime;
		}

		return detectedOperations;
	}
}