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, int? index = null) where T : Result
        {
            if(index is null)
                result.Messages.Add(message);
            else
				result.Messages.Insert(index.Value, message);

			return result;
        }

        public static T Message<T>(this T result, int? index = null, params string[] messages) where T : Result
        {
            if(index is null)
                result.Messages.AddRange(messages);
            else
				result.Messages.InsertRange(index.Value, messages);

			return result;
        }

        public static T Message<T>(this T result, IEnumerable<string> messages, int? index = null) where T : Result
        {
            if(index is null)
                result.Messages.AddRange(messages);
            else
				result.Messages.InsertRange(index.Value, 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, IEnumerable<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 bool HasFlag(this IEnumerable<Notice> notices, Enum flag) => notices.Any(n => n.Flag?.ToString() == flag.ToString());

        public static bool HasAnyFlag(this IEnumerable<Notice> notices, params Enum[] flags) => flags.Any(f => notices.HasFlag(f));

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

        public static async Task<I> ThenAsync<I>(this Result result, Func<Task<I>> SuccessAsync, Func<List<string>, List<Notice>, I> Fail)
        {
            return result.IsSuccess ? await SuccessAsync() : Fail(result.Messages, result.Notices);
        }

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

        public static async Task<I> ThenAsync<T, I>(this DataResult<T> result, Func<T, Task<I>> SuccessAsync, Func<List<string>, List<Notice>, I> Fail)
        {
            return result.IsSuccess ? await SuccessAsync(result.Data) : Fail(result.Messages, result.Notices);
        }

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

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

        public static async Task<I> ThenAsync<T, I>(this Task<DataResult<T>> tResult, Func<T, I> Success, Func<List<string>, List<Notice>, I> Fail)
        {
            DataResult<T> result = await tResult;
            return result.IsSuccess ? Success(result.Data) : Fail(result.Messages, result.Notices);
        }

        public static async Task<I> ThenAsync<T, I>(this Task<DataResult<T>> tResult, Func<T, Task<I>> SuccessAsync, Func<List<string>, List<Notice>, I> Fail)
        {
            DataResult<T> result = await tResult;
            return result.IsSuccess ? await SuccessAsync(result.Data) : Fail(result.Messages, result.Notices);
        }

        public static string Join<T>(this IEnumerable<T> values, string start = "", string seperator = ". ", string end = ".") 
            => new StringBuilder(start).Append(string.Join(seperator, values)).Append(end).ToString();

        public static void LogNotice(this ILogger 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());
            }
        }

        public static void LogNotice(this ILogger logger, Result result, string start = ": ", string seperator = ". ", string end = ".\n")
            => logger.LogNotice(notices: result.Notices, start: start, seperator: seperator, end: end);

        public static bool IsRight(this DataResult<bool> bResult) => bResult.Data;

        public static bool IsWrong(this DataResult<bool> bResult) => !bResult.Data;
    }
}