using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.Office.Core;
using Microsoft.Office.Interop.Word;
using UtilLib;

namespace AIProofread.Model
{
    /// <summary>
    /// 文档信息 包含文档相关数据、面板及对文档的相关操作
    /// </summary>
    public class DocumentInfo
    {
        private static char[] ArticleSpecialChars = new char[4] { '\a', '\r', '\v', '\f' };

        //private Document currentDocument;
        public Document CurrentDocument { get; set; }
        private string fileName;
        private string uniqueId;

        private List<Range> ranges = new List<Range>();
        public string UniqueId
        {
            get { return uniqueId; }

        }

        // 计算uniqueId
        private void ComputeUniqueId()
        {
            string filename = CurrentDocument.FullName;
            if (!string.IsNullOrEmpty(uniqueId) || string.IsNullOrEmpty(filename))
            {
                return;
            }
            // 通过文档路径生成唯一id
            uniqueId = filename.GetHashCode().ToString();
        }

        // 初始化
        public DocumentInfo(Document doc)
        {
            this.CurrentDocument = doc;
        }

        public void Initialize()
        {
            ranges.Clear();
            ComputeUniqueId();
        }

        //处理文档选区时 判断当前选区是否有校对项 有则选择该范围
        public void ProcessSelectionChange(Selection s)
        {
            // 判断选区内是否有书签
            if (s.Bookmarks != null && s.Bookmarks.Count > 0)
            {
                // 判断是否时点击 点击的起始和结束位置相同
                if (s.Range.Start == s.Range.End)
                {
                    // 
                    var count = s.Bookmarks.Count;
                    // 原则只有一个书签
                    //foreach (Microsoft.Office.Interop.Word.Bookmark item in s.Bookmarks)
                    //{
                    //    int proofreadId = Config.GetBookmarkIdByName(item.Name);
                    //    if (proofreadId > 0)
                    //    {
                    //        //Bridge.bridge.SelectMarkById(proofreadId, 0);
                    //        return;
                    //    }
                    //}
                }
            }
        }

        // 获取当前文档文本
        public string GetText()
        {
            return CurrentDocument.Range().Text;
        }

        /// <summary>
        /// 获取当前选中文本
        /// </summary>
        /// <returns></returns>
        public string GetSelectedText()
        {
            return CurrentDocument.Range().Text;
        }

        /// <summary>
        /// 获取指定选区的文本
        /// </summary>
        /// <param name="range"></param>
        /// <returns></returns>
        public string GetRangeText(Range range)
        {
            string text = range?.Text;
            return string.IsNullOrEmpty(text) ? "" : text;
        }

        // 定位所有的校对项
        public void LocateAllProofreadItems(List<CorrectContext> list)
        {
            // 获取所有的校对项
            //List<Range> proofreadItems = GetProofreadItems();
            var prevOffset = 0;
            foreach (var item in list)
            {
                if (item.CorrectItems != null && item.CorrectItems.Count > 0)
                {
                    foreach (var correct in item.CorrectItems)
                    {
                        var range = LocateProofreadItem(correct,item,ref prevOffset);
                        if (range == null) continue;

                    }
                }
            }

        }

        /// <summary>
        /// 查找偏移量
        /// </summary>
        private static readonly int INSERT_FIND_OFFSET = 5;
        /// <summary>
        /// 定位校对项
        /// </summary>
        /// <param name="correct">校对项</param>
        /// <param name="ctx">校对上下文</param>
        /// <param name="prevOffset">上一步的</param>
        /// <returns></returns>
        private Range LocateProofreadItem(CorrectItem correct, CorrectContext ctx, ref int prevOffset)
        {
            var document = CurrentDocument;
            // 校对项的段落号超过文档的段落数，直接返回
            if (ctx.ParagraphNumber > document.Paragraphs.Count) return null;
            // 获取当前段落
            var paragraph = document.Paragraphs[ctx.ParagraphNumber];
            if (paragraph == null) return null;


            var paraRange = paragraph.Range;
            var paraText = paraRange.Text;
            var paraStart = paraRange.Start;

            var offset = paraStart + ctx.SentenceOffset;
            //var cutLength = Math.Min(c.InsertLen, paraText.Length - offset);
            var sentence = paraText.Substring(ctx.SentenceOffset, ctx.InsertLength);
            if (sentence == ctx.Insert)
            { // 比对原始内容与校对原文是否一致
                var range = document.Range(offset + correct.Start, offset + correct.End);
                // 
                if (range.Text == correct.Origin) return range;
            }

            var originText = ctx.Insert;
            // 如果是新增 则查找定位
            if (correct.Tag == "i")
            {
                // 找前缀
                var prefix1 = correct.Start > 2 ? (
                    correct.Start > INSERT_FIND_OFFSET
                        ? originText.Substring(correct.Start - INSERT_FIND_OFFSET, INSERT_FIND_OFFSET)
                        : originText.Substring(0, correct.Start)
                    ) : null;
                // 找后缀
                var suffix1 = prefix1 == null ? (
                    correct.End + INSERT_FIND_OFFSET < originText.Length
                    ? originText.Substring(correct.Start, INSERT_FIND_OFFSET)
                : originText.Substring(correct.Start, originText.Length - correct.Start)
                    ) : null;
                // 偏移量
                var start1 = prefix1 != null || suffix1 != null
                    ? paraText.IndexOf(prefix1 ?? suffix1, prevOffset)
                    : -1;
                if (start1 != -1)
                {
                    var findOffset = paraStart + start1 + (prefix1 != null ? prefix1.Length : 0);
                    return document.Range(findOffset, findOffset);
                }
            }

            // 执行查找
            int wordStart = correct.Start;
            int wordEnd = correct.End;

            // 找前缀
            var prefix = wordStart > 2 ? (
                wordStart > INSERT_FIND_OFFSET
                    ? originText.Substring(wordStart - INSERT_FIND_OFFSET, INSERT_FIND_OFFSET)
                    : originText.Substring(0, wordStart)
                ) : null;

            // 找后缀
            var suffix = prefix == null ? (
                wordEnd + INSERT_FIND_OFFSET < originText.Length
                ? originText.Substring(wordStart, INSERT_FIND_OFFSET)
                : originText.Substring(wordStart, originText.Length - wordStart)
                ) : null;
            var start = prefix != null || suffix != null
                        ? paraText.IndexOf(prefix ?? suffix, prevOffset) // item.start + 
                        : -1;
            if (start != -1)
            {
                var findOffset = paraRange.Start + start + (prefix != null ? prefix.Length : 0);
                var range = document.Range(findOffset, findOffset + wordEnd - wordStart);
                if (range.Text == correct.Origin) { return range; }
            }
            // 直接定位查找
            start = paraText.IndexOf(correct.Origin, prevOffset);
            if (start == -1) return null;
            // 定位整体开始位置
            start = paraStart + start;
            return document.Range(start, start + correct.Origin.Length);

        }


       

    }
}