#nullable enable

using System;
using System.Linq;
using Crowdin.Plugin.Server_API.Helpers;

namespace Crowdin.Plugin.Helpers
{
    public static class ContextEntryIdHelper
    {
        private const string Marker = "Unity Entry ID: ";
        
        public static bool TryReadEntryIdFromContextString(string? context, out long? entryId, out string strippedContext)
        {
            entryId = null;
            strippedContext = context ?? string.Empty;

            if (!SettingsHelper.GetToggleStatus_PreserveEntryIdsOnImport()) return false;

            if (string.IsNullOrWhiteSpace(context)) return false;

            string[] lines = context!.Split("\n", StringSplitOptions.RemoveEmptyEntries);
            
            if (lines.Length < 2) return false;
            
            string entryIdLine = lines[1];

            if (!entryIdLine.StartsWith(Marker)) return false;

            string markerData = entryIdLine[Marker.Length..];

            if (!long.TryParse(markerData, out long parsedId)) return false;

            entryId = parsedId;
            
            strippedContext = string.Join("\n", new[] { lines[0] }.Concat(lines.Skip(2)));
            return true;
        }

        public static string AppendOrUpdateEntryIdInContextString(string? context, long entryId)
        {
            var newMarkerLine = $"{Marker}{entryId}";

            if (string.IsNullOrEmpty(context))
            {
                return newMarkerLine;
            }

            string[] lines = context!.Split("\n");

            if (lines[0].StartsWith(Marker))
            {
                lines[0] = newMarkerLine;
            }
            else
            {
                return newMarkerLine + "\n" + context;
            }

            return string.Join("\n", lines);
        }
    }
}