using API.Services.Interfaces;
using DAL.Contexts;
using DAL.Models;
using System.Linq.Expressions;

namespace API.Services
{
	public class GrantManager : IGrantManager
	{
		private readonly SASGContext _context;
		private ILogger<GrantManager> _logger;

		public GrantManager(ILogger<GrantManager> logger, SASGContext context)
		{
			_logger = logger;
			_context = context;
		}

		public bool hasGrant(ulong permissionId, string grantName)
		{
			return getGrant(x => x.permissionId == permissionId && x.name.Equals(grantName)).Any();
		}

		public List<string> getValues(ulong permissionId, string grantName)
		{
			List<Grant> grants = getGrant(x => x.permissionId == permissionId && x.name.StartsWith(grantName + ".")).ToList();

			List<string> values = [];
			foreach (Grant grant in grants)
			{
				string value = grant.name.Substring(grantName.Length + 1);
				if (value.Contains('.'))
					// Were not looking at a value and instead another grant
					continue;

				values.Add(value);
			}

			return values;
		}

		public List<string> getStringValues(ulong permissionId, string grantName)
		{
			List<string> values = getValues(permissionId, grantName);

			// Get rid of numbers
			values = values.Where(x => !Int32.TryParse(x, out int _)).ToList();

			return values;
		}

		public List<int> getIntValues(ulong permissionId, string grantName)
		{
			List<string> values = getValues(permissionId, grantName);
			List<int> intValues = [];

			Parallel.ForEach(values, x =>
			{
				if (Int32.TryParse(x, out int parsed))
					intValues.Add(parsed);
			});

			return intValues;
		}

		public List<ulong> getULongValues(ulong permissionId, string grantName)
		{
			List<string> values = getValues(permissionId, grantName);
			List<ulong> uLongValues = [];

			Parallel.ForEach(values, x =>
			{
				if (UInt64.TryParse(x, out ulong parsed))
					uLongValues.Add(parsed);
			});

			return uLongValues;
		}

		private IEnumerable<Grant> getGrant(Expression<Func<Grant, bool>> whereClause)
		{
			return _context.Set<Grant>().Where(whereClause);
		}
	}
}