using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using AsbCloudApp.Data;
using AsbCloudApp.Data.WellOperationImport;
using AsbCloudApp.Exceptions;
using AsbCloudApp.Repositories;
using AsbCloudApp.Requests;
using AsbCloudApp.Services.WellOperationImport;

namespace AsbCloudInfrastructure.Services.WellOperationImport;

public class WellOperationImportService : IWellOperationImportService
{
	private readonly IEnumerable<IWellOperationExcelParser> excelParsers;
	private readonly IWellOperationRepository wellOperationRepository;

	private static readonly DateTime dateLimitMin = new(2001, 1, 1, 0, 0, 0);
	private static readonly DateTime dateLimitMax = new(2099, 1, 1, 0, 0, 0);
	private static readonly TimeSpan drillingDurationLimitMax = TimeSpan.FromDays(366);

	public WellOperationImportService(IEnumerable<IWellOperationExcelParser> excelParsers,
		IWellOperationRepository wellOperationRepository)
	{
		this.excelParsers = excelParsers;
		this.wellOperationRepository = wellOperationRepository;
	}

	public async Task ImportAsync(int idWell, int idUser, Stream stream, WellOperationParserOptionsDto options, bool deleteBeforeImport, 
		CancellationToken cancellationToken)
	{
		var excelParser = excelParsers.FirstOrDefault(p => 
							p.IdTemplate == options.IdTemplate &&
							p.IdTypes.Contains(options.IdType))
						?? throw new ArgumentInvalidException(nameof(options.IdTemplate), "Невозможно импортировать файл");
		
		IEnumerable<RowDto> rows;
		var validationErrors = new List<string>();

		var sections = wellOperationRepository.GetSectionTypes();
		var categories = wellOperationRepository.GetCategories(false);

		rows = options.IdTemplate switch
		{
			0 => excelParser.Parse(stream, options),
			_ => excelParser.Parse(stream, options)
		};

		var operations = new List<WellOperationDto>();

		foreach (var row in rows)
		{
			try
			{
				var section = sections.FirstOrDefault(s =>
					string.Equals(s.Caption, row.Section, StringComparison.CurrentCultureIgnoreCase));

				if (section is null)
					throw new FileFormatException($"Лист '{options.SheetName}'. В строке '{row.Number}' не удалось определить секцию");

				var category = categories.FirstOrDefault(c =>
					string.Equals(c.Name, row.Category, StringComparison.CurrentCultureIgnoreCase));

				if (category is null)
					throw new FileFormatException($"Лист '{options.SheetName}'. В строке '{row.Number}' не удалось определить операцию");

				if (row.DepthStart is not (>= 0d and <= 20_000d))
					throw new FileFormatException(
						$"Лист '{options.SheetName}'. Строка '{row.Number}' некорректная глубина на начало операции");

				if (row.DepthEnd is not (>= 0d and <= 20_000d))
					throw new FileFormatException(
						$"Лист '{options.SheetName}'. Строка '{row.Number}' некорректная глубина на конец операции");

				if (row.Date < dateLimitMin && row.Date > dateLimitMax)
					throw new FileFormatException(
						$"Лист '{options.SheetName}'. Строка '{row.Number}' неправильно получена дата начала операции");

				if (operations.LastOrDefault()?.DateStart > row.Date)
					throw new FileFormatException(
						$"Лист '{options.SheetName}' строка '{row.Number}' дата позднее даты предыдущей операции");

				if (row.Duration is not (>= 0d and <= 240d))
					throw new FileFormatException($"Лист '{options.SheetName}'. Строка '{row.Number}' некорректная длительность операции");

				operations.Add(new WellOperationDto
				{
					IdWell = idWell,
					IdUser = idUser,
					IdType = options.IdType,
					IdWellSectionType = section.Id,
					IdCategory = category.Id,
					CategoryInfo = row.CategoryInfo,
					DepthStart = row.DepthStart,
					DepthEnd = row.DepthEnd,
					DateStart = row.Date,
					DurationHours = row.Duration
				});
			}
			catch (FileFormatException ex)
			{
				validationErrors.Add(ex.Message);
			}
		}

		if (operations.Any() && operations.Min(o => o.DateStart) - operations.Max(o => o.DateStart) > drillingDurationLimitMax)
			validationErrors.Add($"Лист {options.SheetName} содержит диапазон дат больше {drillingDurationLimitMax}");

		if (validationErrors.Any())
			throw new FileFormatException(string.Join("\r\n", validationErrors));

		if (!operations.Any())
			return;

		if (deleteBeforeImport)
		{
			var existingOperations = await wellOperationRepository.GetAsync(new WellOperationRequest
			{
				IdWell = idWell
			}, cancellationToken);

			await wellOperationRepository.DeleteAsync(existingOperations.Select(o => o.Id), cancellationToken);
		}

		await wellOperationRepository.InsertRangeAsync(operations, cancellationToken);
	}
}