using DiffMatchPatch;
using Microsoft.AspNetCore.Components;
using System;
using System.Collections.Generic;
using System.Text;
using System.Threading.Tasks;
using System.Web;

namespace MP.Prog.Components
{
    public partial class DiffView
    {
        #region Public Properties

        [Parameter]
        public bool CompareVers { get; set; } = false;

        [Parameter]
        public EventCallback<int> diffDone { get; set; }

        [Parameter]
        public string NewText
        {
            get => _newText;
            set => _newText = value;
        }

        [Parameter]
        public string NewTitle { get; set; } = "Attuale";

        [Parameter]
        public string OldText
        {
            get => _oldText;
            set => _oldText = value;
        }

        [Parameter]
        public string OldTitle { get; set; } = "Archivio";

        #endregion Public Properties

        #region Protected Fields

        protected string _newText = "";

        protected string _oldText = "";

        protected string newResult = "";

        protected string oldResult = "";

        protected int pHeight = 25;

        #endregion Protected Fields

        #region Protected Properties

        protected int numChanges { get; set; } = 0;

        #endregion Protected Properties

        #region Protected Methods

        protected override Task OnInitializedAsync()
        {
            ReloadData();
            return base.OnInitializedAsync();
        }

        protected override void OnParametersSet()
        {
            ReloadData();
        }

        protected void ReloadData()
        {
            numChanges = 0;
            // calcolo diff
            diff_match_patch dmp = new diff_match_patch();
            List<Diff> diff = dmp.diff_main(OldText, NewText);
            //List<Diff> diff = dmp.diff_main(oldTextFix, newTextFix);
            dmp.diff_cleanupSemantic(diff);

            // predispongo la stringa secondo l'elenco dei diff....
            StringBuilder sbNew = new StringBuilder();
            StringBuilder sbOld = new StringBuilder();
            foreach (var item in diff)
            {
                // se fosse testo vuoto --> metto spazio!
                if (string.IsNullOrEmpty(item.text))
                {
                    item.text = " ";
                }
                switch (item.operation)
                {
                    case Operation.DELETE:
                        sbOld.Append($"<span class=\"border border-success bg-success bg-opacity-25\">{HttpUtility.HtmlEncode(item.text)}</span>");
                        numChanges++;
                        break;

                    case Operation.INSERT:
                        sbNew.Append($"<span class=\"border border-danger bg-danger bg-opacity-25\">{HttpUtility.HtmlEncode(item.text)}</span>");
                        numChanges++;
                        break;

                    case Operation.EQUAL:
                        sbNew.Append($"<span class=\"text-dark\">{HttpUtility.HtmlEncode(item.text)}</span>");
                        sbOld.Append($"<span class=\"text-dark\">{HttpUtility.HtmlEncode(item.text)}</span>");
                        break;

                    default:
                        break;
                }
            }

            newResult = sbNew.ToString();
            oldResult = sbOld.ToString();
            var pUpd = Task.Run(async () =>
            {
                await diffDone.InvokeAsync(numChanges);
            });
            pUpd.Wait();
        }

        #endregion Protected Methods

        #region Private Fields

        private string sepDest = "<br />";

        #endregion Private Fields

        #region Private Methods

        private MarkupString StrFix(string origVal)
        {
            string fixVal = origVal.Trim()
                    .Replace("  ", "&nbsp;&nbsp;")
                    .Replace(Environment.NewLine, sepDest);
            return new MarkupString(fixVal);
        }

        #endregion Private Methods
    }
}