using LCU.Library.Internal.ArchiverApiLib.Repositories;
using LCU.Library.Internal.ArchiverApiModel.Entities;
using System.Data.SqlClient;
using LCU.Library.Internal.Exceptions;
using Serilog;
using System;
using System.Collections.Generic;
using System.Threading.Tasks;

namespace LCU.Api.Internal.ArchiverApi.Services;

public class RegexMappingService : IRegexMappingService
{
    private readonly IRegexMappingRepository _regexMappingRepository;
    private readonly IUnitOfWork _unitOfWork;

    public RegexMappingService(IUnitOfWork unitOfWork,
                                     IRegexMappingRepository regexMappingRepository)
    {
        _unitOfWork = unitOfWork;
        _regexMappingRepository = regexMappingRepository;
    }
    public void DeleteAsync(int regexMappingId)
    {
        try
        {
            var regexMapping = _regexMappingRepository.FindByRegexMappingIdAsync(regexMappingId).Result;
            ArgumentNullException.ThrowIfNull(regexMapping);
            _regexMappingRepository.Remove(regexMapping);
            _unitOfWork.Complete();
        }
        catch (SqlException sqlException)
        {
            Log.Error(sqlException, $"SQL failure removing regex mapping. RegexMappingId: {regexMappingId}");
            throw new ServiceException($"SQL failure removing regex mapping. RegexMappingId: {regexMappingId}");
        }
        catch (Exception exception)
        {
            Log.Error(exception, $"Failure removing regex mapping. RegexMappingId: {regexMappingId}");
            throw new ServiceException($"Failure removing regex mapping. RegexMappingId: {regexMappingId}");
        }
    }

    public async Task<IEnumerable<RegexMapping>> GetAsync()
    {
        try
        {
            return await _regexMappingRepository.ListAsync();
        }
        catch (Exception exception)
        {
            Log.Error(exception, "Failure retrieving regex mappings.");
            throw new ServiceException("Failure retrieving regex mappings.");
        }
    }

    public async Task<RegexMapping> GetByApplicationMappingIdAsync(int id)
    {
        try
        {
            var regexMapping = await _regexMappingRepository.FindByApplicationMappingIdAsync(id);
            ArgumentNullException.ThrowIfNull(regexMapping);
            return regexMapping;
        }
        catch (Exception exception)
        {
            Log.Error(exception, $"Failure retrieving regex mapping with id {id}.");
            throw new ServiceException($"Failure retrieving regex mapping with id {id}.");
        }
    }

    public async Task<RegexMapping> GetByRegexMappingIdAsync(int id)
    {
        try
        {
            var regexMapping = await _regexMappingRepository.FindByRegexMappingIdAsync(id);
            ArgumentNullException.ThrowIfNull(regexMapping);
            return regexMapping;
        }
        catch (Exception exception)
        {
            Log.Error(exception, $"Failure retrieving regex mapping with id {id}.");
            throw new ServiceException($"Failure retrieving regex mapping with id {id}.");
        }
    }

    public async Task<RegexMapping> SaveAsync(RegexMapping regexMapping)
    {
        try
        {
            if (CheckTagInvalid(regexMapping.Tag))
            {
                throw new Exception("Invalid Tag: "+regexMapping.Tag);
            }
            var result = await _regexMappingRepository.AddAsync(regexMapping);
            await _unitOfWork.CompleteAsync();

            return result;
        }
        catch (Exception exception)
        {
            Log.Error(exception, "Failure saving regex mapping");
            throw new ServiceException("Failure saving regex mapping");
        }
    }

    public RegexMapping Update(RegexMapping regexMapping)
    {
        try
        {
            if (CheckTagInvalid(regexMapping.Tag))
            {
                throw new Exception("Invalid Tag: "+regexMapping.Tag);
            }
            var existing = GetByRegexMappingIdAsync(regexMapping.RegexMappingId).Result;
            ArgumentNullException.ThrowIfNull(existing);
            
            existing.ApplicationMappingId = regexMapping.ApplicationMappingId;
            existing.Regex = regexMapping.Regex;
            existing.Tag = regexMapping.Tag;

            _regexMappingRepository.Update(existing);
            _unitOfWork.Complete();

            return existing;
        }
        catch (SqlException sqlException)
        {
            Log.Error(sqlException, "SQL Failure updating regex mapping");
            throw new ServiceException("SQL Failure updating regex mapping");
        }
        catch (Exception exception)
        {
            Log.Error(exception, "Failure updating regex mapping");
            throw new ServiceException("Failure updating regex mapping");
        }
    }

    private bool CheckTagInvalid(string tag)
    {
        var endIndex = tag.IndexOf('}');
        var sub = tag.Substring(0, 6);
        if (tag.Substring(0,6) == "{Regex" && endIndex >= 7)
        {
            var tagNumber = Int32.Parse(tag.Substring(6, endIndex - 6));
            return tagNumber >= 0 && tagNumber <= 3;
        }
        return true;
    }
}