using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using DiffPlex;
using System.IO.Packaging;
using System.Text.RegularExpressions;
using System.Linq;
using Microsoft.Office.Interop.Word;
using wispro.sp.entity.CompareCase;


namespace wispro.sp.utility
{
    /// <summary>
    /// 比较两个Docx文档中文字的不同
    /// </summary>
    public class CompareDocx
    {
        public class PatentDocument
        {
            public string FilePath {  get; set; }

            public string Abstract { get; set; }

            public string Claim { get; set; }

            public string FullText { get; set; }

            public string DocumentString { get; set; }

            public PatentDocument(string filePath) { 
                this.FilePath = filePath;

                if (!System.IO.File.Exists(this.FilePath) )
                {
                    throw new ApplicationException("指定的文件不存在！");
                }
                
                if (this.FilePath.EndsWith(".doc"))
                {
                    DocumentString = GetDocTxt(this.FilePath);
                }
                else
                {
                    if (this.FilePath.ToLower().EndsWith(".docx"))
                    {
                        DocumentString = GetDocxTxt(this.FilePath);
                    }
                }
            }

            private string GetDocTxt(string filePath)
            {
                Application word = null;
                Document doc = null;
                string content = string.Empty;

                try
                {
                    // 创建Word应用实例
                    word = new Application();
                    // 打开Word文档
                    System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);

                    if (fileInfo.Name.Contains("-保密-"))
                    {
                        return null;
                    }
                    else
                    {
                        doc = word.Documents.Open(fileInfo.FullName);
                        // 读取文档内容
                        content = doc.Content.Text;

                        List<string> lines = content.Split(new string[] { "\f", "\r" }, StringSplitOptions.None).ToList();
                        return List2String(lines);
                    }

                }
                catch (Exception ex)
                {
                    throw new Exception($"读取Word文档时发生错误: {ex.Message}");
                }
                finally
                {
                    // 关闭文档
                    if (doc != null)
                    {
                        doc.Close();
#pragma warning disable CA1416 // 验证平台兼容性
                        System.Runtime.InteropServices.Marshal.ReleaseComObject(doc);
#pragma warning restore CA1416 // 验证平台兼容性
                    }
                    // 退出Word应用
                    if (word != null)
                    {
                        word.Quit();
#pragma warning disable CA1416 // 验证平台兼容性
                        System.Runtime.InteropServices.Marshal.ReleaseComObject(word);
#pragma warning restore CA1416 // 验证平台兼容性
                    }
                }


            }

            private string GetDocxTxt(string filepath)
            {
                var oldtext = getDocxMainXml(filepath);
                var oldlines = ExtractWPTextFromXml(oldtext);
                oldtext = List2String(oldlines);

                return oldtext;
            }

            private string List2String(List<string> lines)
            {
                string[] array = { "权利要求书", "说明书摘要", "说明书" ,"背景技术","发明内容", "技术领域", "具体实施方式", "摘要附图", "说明书附图" };

                StringBuilder sb = new StringBuilder();
                string lastBlock = string.Empty;
                foreach (var line in lines)
                {
                    if (!string.IsNullOrEmpty(line))
                    {
                        sb.Append(line.Trim() + "\r\n");

                        
                        if(Array.Exists(array, element => element == line.Replace("\u0001","").Replace(" ","").Trim()))
                        {
                            lastBlock = line.Replace("\u0001", "").Replace(" ", "").Trim();
                        }
                        else
                        {
                            switch(lastBlock) {
                                case "权利要求书":
                                    this.Claim = this.Claim + "\r\n" + line;
                                    break;
                                case "说明书摘要":
                                    this.Abstract = this.Abstract + "\r\n" + line;
                                    break;
                                case "说明书":
                                case "背景技术":
                                case "发明内容":
                                case "技术领域":
                                case "具体实施方式":
                                    this.FullText = this.FullText + "\r\n" + line;
                                    break;

                            }
                        }
                    }
                }

                this.Abstract = string.IsNullOrEmpty(this.Abstract)?string.Empty: this.Abstract.Trim();
                this.Claim = string.IsNullOrEmpty(this.Claim) ? string.Empty : this.Claim.Trim();
                this.FullText = string.IsNullOrEmpty(this.FullText) ? string.Empty : this.FullText.Trim();

                return sb.ToString();
            }

            private string getDocxMainXml(string filePath)
            {
                string text = string.Empty;
                using (Package package = Package.Open(filePath, FileMode.Open))
                {
                    var Parts = package.GetParts();

                    foreach (var part in Parts)
                    {
                        if (part.ContentType.StartsWith("application/vnd.openxmlformats-officedocument.wordprocessingml.document.main"))
                        {
                            using (Stream stream = part.GetStream())
                            {
                                StreamReader reader = new StreamReader(stream);
                                text = reader.ReadToEnd();
                                break;
                            }
                        }
                    }

                    return text;
                }
            }

            private List<string> ExtractWPTextFromXml(string xmlText)
            {
                List<string> lines = new List<string>();
                // 使用正则表达式匹配 <w:t> 标签的内容
                MatchCollection matches = Regex.Matches(xmlText, "(<w:p\\s.*?>|<w:p>)(.*?)</w:p>");

                foreach (Match match in matches)
                {
                    lines.Add(ExtractWtTextFromXml(match.Groups[2].Value));
                }
                return lines;
            }

            private string ExtractWtTextFromXml(string xmlText)
            {
                // 使用正则表达式匹配 <w:t> 标签的内容
                MatchCollection matches = Regex.Matches(xmlText, "(<w:t\\s.*?>|<w:t>)(.*?)</w:t>");
                StringBuilder sb = new StringBuilder();
                foreach (Match match in matches)
                {
                    sb.Append(match.Groups[2].Value);
                }
                return sb.ToString();
            }
        }

        /// <summary>
        /// 原文档路径
        /// </summary>
        public PatentDocument oldDocument { get; set; }

        /// <summary>
        /// 修订后文档路径
        /// </summary>
        public PatentDocument newDocument { get; set; }

        /// <summary>
        /// 权力要求比较结果
        /// </summary>
        public CompareResult ClaimResult { get; set; }

        /// <summary>
        /// 摘要比较结果
        /// </summary>
        public CompareResult AbstractResult { get; set; }

        /// <summary>
        /// 说明书比较结果
        /// </summary>
        public CompareResult FulltextResult { get; set; }

        /// <summary>
        /// 所有文字比较结果
        /// </summary>
        public CompareResult AllStringResult { get; set; }

        /// <summary>
        /// 比较两个文档
        /// </summary>
        /// <param name="oldFile"></param>
        /// <param name="newFile"></param>
        public void Compare(string oldFile, string newFile)
        {
            this.oldDocument =new PatentDocument(oldFile);
            this.newDocument =new PatentDocument(newFile);

            if (!string.IsNullOrEmpty(this.oldDocument.Claim) && !string.IsNullOrEmpty(this.newDocument.Claim))
            {
                this.ClaimResult = StringCompare(this.oldDocument.Claim, this.newDocument.Claim);
            }

            if (!string.IsNullOrEmpty(this.oldDocument.Abstract) && !string.IsNullOrEmpty(this.newDocument.Abstract))
                this.AbstractResult = StringCompare(this.oldDocument.Abstract, this.newDocument.Abstract);

            if (!string.IsNullOrEmpty(this.oldDocument.FullText) && !string.IsNullOrEmpty(this.newDocument.FullText))
                this.FulltextResult = StringCompare(this.oldDocument.FullText, this.newDocument.FullText);

            if (!string.IsNullOrEmpty(this.oldDocument.DocumentString) && !string.IsNullOrEmpty(this.newDocument.DocumentString))
                this.AllStringResult = StringCompare(this.oldDocument.DocumentString, this.newDocument.DocumentString);

        }

        /// <summary>
        /// 比较两个文档
        /// </summary>
        /// <exception cref="ApplicationException"></exception>
        public CompareResult StringCompare(string oldtext,string newtext)
        {
            CompareResult result = new CompareResult();
            var differ = new Differ();

            if(oldtext == null) { oldtext = ""; }
            if(newtext == null) { newtext = ""; }

            result.oldWordCount = oldtext.Length;
            result.newWordCount = newtext.Length;
            
            var diff = differ.CreateCharacterDiffs(oldtext, newtext, true);
            //result.EditCount = diff.DiffBlocks.Count;

            int lastPos = 0;

            string _CompareResultString = "";
            string lastResult = "";
            List<string> ModifyList = new List<string>();
            foreach (var change in diff.DiffBlocks)
            {
                string strModifyStr = "";
                

                lastResult += oldtext.Substring(lastPos, change.DeleteStartA - lastPos);
                _CompareResultString += oldtext.Substring(lastPos, change.DeleteStartA - lastPos);
                lastPos = change.DeleteStartA + change.DeleteCountA;


                if (change.DeleteCountA > 0)
                {
                    strModifyStr += $"<strike  style=\"text-decoration: line-through; color: red;\">{oldtext.Substring(change.DeleteStartA, change.DeleteCountA)}</strike>";
                    _CompareResultString += $"<strike  style=\"text-decoration: line-through; color: red;\">{oldtext.Substring(change.DeleteStartA, change.DeleteCountA)}</strike>";
                }

                if (change.InsertCountB > 0)
                {
                    strModifyStr += $"<u style=\"text-decoration: underline; color: blue;\">{newtext.Substring(change.InsertStartB, change.InsertCountB)}</u>";
                    _CompareResultString += $"<u style=\"text-decoration: underline; color: blue;\">{newtext.Substring(change.InsertStartB, change.InsertCountB)}</u>";
                    lastResult += newtext.Substring(change.InsertStartB, change.InsertCountB);
                }

                if(!ModifyList.Contains(strModifyStr))
                {
                    ModifyList.Add(strModifyStr);
                    result.DeleteCount += change.DeleteCountA;
                    result.InsertCount += change.InsertCountB;
                    result.EditCount += 1;
                }
                
            }

            lastResult += oldtext.Substring(lastPos);
            _CompareResultString += oldtext.Substring(lastPos);
            _CompareResultString = _CompareResultString.Replace("\r\n", "<br/>");

            result.CompareResultString = _CompareResultString;

            result.TextSimilarity = CosineSimilarity.Calculate(oldtext, newtext);

            return result;

        }

        
    }
}