Lidarr/NzbDrone.Common/EnsureThat/EnsureStringExtensions.cs

using System;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;
using NzbDrone.Common.EnsureThat.Resources;

namespace NzbDrone.Common.EnsureThat
{
    [DebuggerStepThrough]
    public static class EnsureStringExtensions
    {
        [DebuggerStepThrough]
        public static Param<string> IsNotNullOrWhiteSpace(this Param<string> param)
        {
            if (string.IsNullOrWhiteSpace(param.Value))
                throw ExceptionFactory.CreateForParamValidation(param.Name, ExceptionMessages.EnsureExtensions_IsNotNullOrWhiteSpace);

            return param;
        }

        [DebuggerStepThrough]
        public static Param<string> IsNotNullOrEmpty(this Param<string> param)
        {
            if (string.IsNullOrEmpty(param.Value))
                throw ExceptionFactory.CreateForParamValidation(param.Name, ExceptionMessages.EnsureExtensions_IsNotNullOrEmpty);

            return param;
        }

        [DebuggerStepThrough]
        public static Param<string> HasLengthBetween(this Param<string> param, int minLength, int maxLength)
        {
            if (string.IsNullOrEmpty(param.Value))
                throw ExceptionFactory.CreateForParamValidation(param.Name, ExceptionMessages.EnsureExtensions_IsNotNullOrEmpty);

            var length = param.Value.Length;

            if (length < minLength)
                throw ExceptionFactory.CreateForParamValidation(param.Name, ExceptionMessages.EnsureExtensions_IsNotInRange_ToShort.Inject(minLength, maxLength, length));

            if (length > maxLength)
                throw ExceptionFactory.CreateForParamValidation(param.Name, ExceptionMessages.EnsureExtensions_IsNotInRange_ToLong.Inject(minLength, maxLength, length));

            return param;
        }

        [DebuggerStepThrough]
        public static Param<string> IsLongerThan(this Param<string> param, int minLength)
        {
            if (string.IsNullOrEmpty(param.Value))
                throw ExceptionFactory.CreateForParamValidation(param.Name, ExceptionMessages.EnsureExtensions_IsNotNullOrEmpty);

            var length = param.Value.Length;

            if (length < minLength)
                throw ExceptionFactory.CreateForParamValidation(param.Name, "The string is not long enough. Must be at least '{0}' but was '{1}' characters long.".Inject(minLength, length));

            return param;
        }

        [DebuggerStepThrough]
        public static Param<string> Matches(this Param<string> param, string match)
        {
            return Matches(param, new Regex(match));
        }

        [DebuggerStepThrough]
        public static Param<string> Matches(this Param<string> param, Regex match)
        {
            if (!match.IsMatch(param.Value))
            {
                throw ExceptionFactory.CreateForParamValidation(param.Name, ExceptionMessages.EnsureExtensions_NoMatch.Inject(param.Value, match));
            }
            return param;
        }


        [DebuggerStepThrough]
        public static Param<string> IsRelativePath(this Param<string> param)
        {
            if (string.IsNullOrWhiteSpace(param.Value))
                throw ExceptionFactory.CreateForParamValidation(param.Name, ExceptionMessages.EnsureExtensions_IsNotNullOrWhiteSpace);

            if (!param.Value.EndsWith("\\"))
            {
                throw ExceptionFactory.CreateForParamValidation(param.Name, string.Format("value [{0}]  is not a valid relative path. relative paths must end with \\", param.Value));
            }

            if (param.Value.Length > 1 && param.Value.StartsWith("\\"))
            {
                throw ExceptionFactory.CreateForParamValidation(param.Name, string.Format("value [{0}]  is not a valid relative path. relative paths can not start with \\", param.Value));
            }


            return param;
        }

        private static readonly Regex windowsInvalidPathRegex = new Regex(@"[/*<>""|]", RegexOptions.Compiled | RegexOptions.IgnoreCase);
        private static readonly Regex windowsPathRegex = new Regex(@"^[a-z]:\\", RegexOptions.Compiled | RegexOptions.IgnoreCase);

        [DebuggerStepThrough]
        public static Param<string> IsValidPath(this Param<string> param)
        {
            if (string.IsNullOrWhiteSpace(param.Value))
                throw ExceptionFactory.CreateForParamValidation(param.Name, ExceptionMessages.EnsureExtensions_IsNotNullOrWhiteSpace);

            if (EnvironmentProvider.IsLinux)
            {
                if (!param.Value.StartsWith(Path.DirectorySeparatorChar.ToString()))
                {
                    throw ExceptionFactory.CreateForParamValidation(param.Name, string.Format("value [{0}]  is not a valid *nix path. paths must start with /", param.Value));
                }
            }
            else
            {
                if (windowsInvalidPathRegex.IsMatch(param.Value))
                {
                    throw ExceptionFactory.CreateForParamValidation(param.Name, string.Format("value [{0}]  is not a valid Windows path. It contains invalid characters", param.Value));
                }

                //Network path
                if (param.Value.StartsWith(Path.DirectorySeparatorChar.ToString())) return param;

                if (!windowsPathRegex.IsMatch(param.Value))
                {
                    throw ExceptionFactory.CreateForParamValidation(param.Name, string.Format("value [{0}]  is not a valid Windows path. paths must be a full path eg. C:\\Windows", param.Value));
                }
            }


            return param;
        }
    }
}