DigitalData.Core/DigitalData.Core.DTO/DTOExtensions.cs

using Microsoft.Extensions.Logging;
using System.Text;

namespace DigitalData.Core.DTO
{
    public static class DTOExtensions
    {
        public static T Message<T>(this T result, string message) where T : Result
        {
            result.Messages.Add(message);
            return result;
        }

        public static T Message<T>(this T result, params string[] messages) where T : Result
        {
            result.Messages.AddRange(messages);
            return result;
        }

        public static T Notice<T>(this T result, Notice notice) where T : Result
        {
            result.Notices.Add(notice);
            return result;
        }

        public static T Notice<T>(this T result, params Notice[] notices) where T : Result
        {
            result.Notices.AddRange(notices);
            return result;
        }

        public static T Notice<T>(this T result, LogLevel level, params Enum[] flags) where T : Result
        {
            var notices = flags.Select(flag => new Notice()
            {
                Flag = flag,
                Level = level
            });
            result.Notices.AddRange(notices);
            return result;
        }

        public static T Notice<T>(this T result, LogLevel level, Enum flag, params string[] messages) where T : Result
        {
            result.Notices.Add(new Notice()
            {
                Flag = flag,
                Level = level,
                Messages = messages.ToList()
            });
            return result;
        }

        public static T Notice<T>(this T result, LogLevel level, params string[] messages) where T : Result
        {
            result.Notices.Add(new Notice()
            {
                Flag = null,
                Level = level,
                Messages = messages.ToList()
            });
            return result;
        }

        public static I Then<I>(this Result result, Func<I> Try, Func<List<string>, List<Notice>, I> Catch)
        {
            return result.IsSuccess ? Try() : Catch(result.Messages, result.Notices);
        }

        public static I Then<T, I>(this DataResult<T> result, Func<T, I> Try, Func<List<string>, List<Notice>, I> Catch)
        {
            return result.IsSuccess ? Try(result.Data) : Catch(result.Messages, result.Notices);
        }

        public static async Task<I> Then<I>(this Task<Result> tResult, Func<I> Try, Func<List<string>, List<Notice>, I> Catch)
        {
            Result result = await tResult;
            return result.IsSuccess ? Try() : Catch(result.Messages, result.Notices);
        }

        public static async Task<I> Then<T, I>(this Task<DataResult<T>> tResult, Func<T, I> Try, Func<List<string>, List<Notice>, I> Catch)
        {
            DataResult<T> result = await tResult;
            return result.IsSuccess ? Try(result.Data) : Catch(result.Messages, result.Notices);
        }
        
        public static void LogNotice<T>(this ILogger<T> logger, IEnumerable<Notice> notices, string start = ": ", string seperator = ". ", string end = ".\n")
        {
            foreach(LogLevel level in Enum.GetValues(typeof(LogLevel)))
            {
                var logNotices = notices.Where(n => n.Level == level);

                if (!logNotices.Any())
                    continue;

                var sb = new StringBuilder();
                foreach(Notice notice in logNotices)
                {
                    if (notice.Flag is not null)
                        sb.Append(notice.Flag);

                    if (notice.Messages.Any())
                        sb.Append(start).Append(string.Join(seperator, notice.Messages)).AppendLine(end);
                    else sb.Append(end);
                }
                logger.Log(level, sb.ToString());
            }
        }
    }
}