using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Text;
using System.Text.RegularExpressions;
using BLL;

namespace FineUIPro.Web.HSSE.PDFDOC
{
    /// <summary>
    /// PDF 书籍维护页：左侧多级目录树 + 右侧富文本内容编辑（UMEditor，可输入文字、上传图片）。
    /// 章节与内容全部手动录入维护：新增书籍 / 新增·编辑·删除章节 / 保存章节富文本内容。
    /// 数据存 Sys_PdfBook / Sys_PdfChapter（内容为 HTML；上传图片在保存时转为 base64 内嵌，正文自包含）。
    /// </summary>
    public partial class PdfBookView : PageBase
    {
        #region 页面加载
        /// <summary>
        /// 页面加载。
        /// </summary>
        protected void Page_Load(object sender, EventArgs e)
        {
            // 显式指定 UTF-8 编码，避免个别环境下中文乱码
            this.Response.ContentEncoding = System.Text.Encoding.UTF8;
            this.Response.Charset = "utf-8";

            if (!IsPostBack)
            {
                BindBooks();
                if (this.drpBook.Items.Count > 0)
                {
                    this.drpBook.SelectedIndex = 0;
                    InitTree(this.drpBook.SelectedValue);
                }
                this.lblProgress.Text = "";
            }
        }
        #endregion

        #region 绑定书籍
        /// <summary>
        /// 绑定书籍下拉框。
        /// </summary>
        private void BindBooks()
        {
            this.drpBook.Items.Clear();
            foreach (PdfBook book in PdfBookService.GetBooks())
            {
                this.drpBook.Items.Add(new FineUIPro.ListItem(book.Title, book.BookId));
            }
        }
        #endregion

        #region 目录树
        /// <summary>
        /// 初始化目录树（按父章节/层级递归建树，支持多级目录）。
        /// </summary>
        private void InitTree(string bookId)
        {
            this.trCatalog.Nodes.Clear();
            this.trCatalog.SelectedNodeID = "";
            var chapters = PdfBookService.GetChapters(bookId);

            // 1) 先为每个章节创建节点
            var nodeMap = new Dictionary<string, FineUIPro.TreeNode>();
            foreach (PdfChapter c in chapters)
            {
                var node = new FineUIPro.TreeNode
                {
                    Text = c.Title,
                    NodeID = c.ChapterId,
                    CommandName = "chapter",
                    CommandArgument = c.ChapterId,
                    ToolTip = c.PageStart > 0 ? ("第" + c.PageStart + " - " + c.PageEnd + " 页") : "",
                    EnableClickEvent = true,
                    Expanded = true   // 页面默认全部展开
                };
                nodeMap[c.ChapterId] = node;
            }

            // 2) 按父章节挂接，没有父级(或父级不在列表)的作为顶级
            var roots = new List<FineUIPro.TreeNode>();
            foreach (PdfChapter c in chapters)
            {
                var node = nodeMap[c.ChapterId];
                if (!string.IsNullOrWhiteSpace(c.ParentChapterId) && nodeMap.ContainsKey(c.ParentChapterId))
                {
                    nodeMap[c.ParentChapterId].Nodes.Add(node);
                }
                else
                {
                    roots.Add(node);
                }
            }

            // 3) 顶级节点加入树
            foreach (var r in roots)
                this.trCatalog.Nodes.Add(r);
        }
        #endregion

        #region 下拉切换
        /// <summary>
        /// 切换书籍。
        /// </summary>
        protected void drpBook_SelectedIndexChanged(object sender, EventArgs e)
        {
            InitTree(this.drpBook.SelectedValue);
            this.htmlContent.Text = "";
            this.hfCurrentChapterId.Text = "";
            this.lblProgress.Text = "";
        }
        #endregion

        #region 目录点击 → 加载章节内容
        /// <summary>
        /// 点击目录节点，把章节富文本内容加载到编辑器。
        /// 所有章节（含带子章节的目录章节）均可编辑自身正文，点击即加载。
        /// </summary>
        protected void trCatalog_NodeCommand(object sender, FineUIPro.TreeCommandEventArgs e)
        {
            if (e.Node == null)
                return;

            string chapterId = e.Node.CommandArgument;
            if (string.IsNullOrWhiteSpace(chapterId))
                chapterId = e.Node.NodeID;

            PdfChapterDetail detail = PdfBookService.GetChapterContent(chapterId);
            this.htmlContent.Text = detail == null ? "" : (detail.Content ?? "");
            this.hfCurrentChapterId.Text = chapterId;
            this.trCatalog.SelectedNodeID = e.Node.NodeID;
            this.lblProgress.Text = "正在编辑：" + (detail == null ? e.Node.Text : detail.Title);
        }
        #endregion

        #region 保存章节内容（富文本）
        /// <summary>
        /// 保存当前章节的富文本内容（HTML；本站上传图片引用自动转为 base64 内嵌存储）。
        /// </summary>
        protected void btnSaveContent_Click(object sender, EventArgs e)
        {
            string chapterId = this.hfCurrentChapterId.Text;
            if (string.IsNullOrWhiteSpace(chapterId))
            {
                FineUIPro.Alert.Show("请先在左侧目录选择章节。");
                return;
            }

            // 本地上传图片转 base64 后入库，正文自包含（不依赖 upload 目录文件）
            string html = EmbedLocalImagesAsBase64(this.htmlContent.Text);

            SQLHelper.ExecutSql("UPDATE dbo.Sys_PdfChapter SET Text=N'" + SqlEsc(html)
                + "' WHERE ChapterId='" + SqlEsc(chapterId) + "'");
            this.lblProgress.Text = "内容已保存：" + DateTime.Now.ToString("HH:mm:ss");
        }

        /// <summary>
        /// 把 HTML 中指向本站 UMeditor 上传相关路径（/res/umeditor/net/..，含 ../../../upload 形态）的图片引用替换为 base64 内嵌。
        /// 已是 data: 的图片与外部 http(s) 图片原样保留；路径非图片扩展名或文件不存在时不做替换（回退原引用）。
        /// </summary>
        private static readonly Regex LocalUploadImgSrcRegex = new Regex(
            "src\\s*=\\s*([\"'])([^\"']*?/res/umeditor/net/[^\"']*?)\\1",
            RegexOptions.IgnoreCase | RegexOptions.Compiled);

        private string EmbedLocalImagesAsBase64(string html)
        {
            if (string.IsNullOrEmpty(html) ||
                html.IndexOf("/res/umeditor/net/", StringComparison.OrdinalIgnoreCase) < 0)
                return html;

            return LocalUploadImgSrcRegex.Replace(html, delegate(Match m)
            {
                string quote = m.Groups[1].Value;
                string raw = m.Groups[2].Value;
                int i = raw.IndexOf("/res/umeditor/net/", StringComparison.OrdinalIgnoreCase);
                if (i < 0)
                    return m.Value;
                string virtualPath = raw.Substring(i);
                int q = virtualPath.IndexOf('?');
                if (q >= 0) virtualPath = virtualPath.Substring(0, q);

                string extCheck = System.IO.Path.GetExtension(virtualPath).ToLowerInvariant();
                if (extCheck != ".png" && extCheck != ".jpg" && extCheck != ".jpeg" && extCheck != ".gif" && extCheck != ".bmp")
                    return m.Value;

                try
                {
                    string physical = Server.MapPath(virtualPath);
                    if (!System.IO.File.Exists(physical))
                        return m.Value;
                    byte[] bytes = System.IO.File.ReadAllBytes(physical);
                    if (bytes.Length == 0)
                        return m.Value;

                    string ext = System.IO.Path.GetExtension(physical).ToLowerInvariant();
                    string mime = ext == ".png" ? "image/png"
                        : ext == ".gif" ? "image/gif"
                        : ext == ".bmp" ? "image/bmp"
                        : "image/jpeg";
                    return "src=" + quote + "data:" + mime + ";base64," + Convert.ToBase64String(bytes) + quote;
                }
                catch
                {
                    return m.Value;
                }
            });
        }
        #endregion

        #region 书籍新增
        /// <summary>
        /// 打开新增书籍弹窗。
        /// </summary>
        protected void btnAddBook_Click(object sender, EventArgs e)
        {
            this.txtBookTitle.Text = "";
            this.WindowBook.Hidden = false;
        }

        /// <summary>
        /// 保存新增书籍。
        /// </summary>
        protected void btnSaveBook_Click(object sender, EventArgs e)
        {
            string title = this.txtBookTitle.Text.Trim();
            if (title.Length == 0)
            {
                FineUIPro.Alert.Show("请输入书名。");
                return;
            }

            string bookId = NewId("PB");
            SQLHelper.ExecutSql(
                "INSERT INTO dbo.Sys_PdfBook (BookId, Title, FilePath, TotalPages, IndexStatus, CreateUser, CreateTime) VALUES ('"
                + SqlEsc(bookId) + "',N'" + SqlEsc(title) + "',NULL,0,2,N'test',GETDATE())");

            this.WindowBook.Hidden = true;
            BindBooks();
            this.drpBook.SelectedValue = bookId;
            InitTree(bookId);
            this.htmlContent.Text = "";
            this.hfCurrentChapterId.Text = "";
            this.lblProgress.Text = "已新增书籍：《" + title + "》，请继续添加章节。";
        }

        /// <summary>
        /// 关闭新增书籍弹窗。
        /// </summary>
        protected void btnCloseBook_Click(object sender, EventArgs e)
        {
            this.WindowBook.Hidden = true;
        }
        #endregion

        #region 章节新增/编辑/删除
        /// <summary>
        /// 打开新增章节弹窗（父级=目录树选中节点，未选中则为顶级章节）。
        /// </summary>
        protected void btnAddChapter_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrEmpty(this.drpBook.SelectedValue))
            {
                FineUIPro.Alert.Show("请先新增/选择书籍。");
                return;
            }

            this.hfEditChapterId.Text = "";
            this.txtChapterTitle.Text = "";
            string parentId = this.trCatalog.SelectedNodeID;
            this.lblParentChapter.Text = string.IsNullOrEmpty(parentId) ? "顶级章节" : "选中节点的子章节";
            this.WindowChapter.Title = "新增章节";
            this.WindowChapter.Hidden = false;
        }

        /// <summary>
        /// 打开编辑章节弹窗（修改选中章节名称）。
        /// </summary>
        protected void btnEditChapter_Click(object sender, EventArgs e)
        {
            string chapterId = this.trCatalog.SelectedNodeID;
            if (string.IsNullOrEmpty(chapterId))
            {
                FineUIPro.Alert.Show("请先在目录中选择要编辑的章节。");
                return;
            }

            DataTable dt = SQLHelper.GetDataTableRunText(
                "SELECT ChapterTitle FROM dbo.Sys_PdfChapter WHERE ChapterId=@id",
                new[] { new SqlParameter("@id", chapterId) });
            if (dt == null || dt.Rows.Count == 0)
            {
                FineUIPro.Alert.Show("未找到该章节。");
                return;
            }

            this.hfEditChapterId.Text = chapterId;
            this.txtChapterTitle.Text = dt.Rows[0]["ChapterTitle"].ToString();
            this.lblParentChapter.Text = "修改章节名称";
            this.WindowChapter.Title = "编辑章节";
            this.WindowChapter.Hidden = false;
        }

        /// <summary>
        /// 保存章节（新增：挂在选中节点下，层级=父级+1；编辑：仅改名）。
        /// 保存后保持选中刚保存的章节：叶子章节加载其内容，目录章节仅刷新选中、不动编辑器。
        /// </summary>
        protected void btnSaveChapter_Click(object sender, EventArgs e)
        {
            string title = this.txtChapterTitle.Text.Trim();
            if (title.Length == 0)
            {
                FineUIPro.Alert.Show("请输入章节名称。");
                return;
            }

            string bookId = this.drpBook.SelectedValue;
            string affectedId;

            if (this.hfEditChapterId.Text != "")
            {
                // 编辑：仅改名称
                affectedId = this.hfEditChapterId.Text;
                SQLHelper.ExecutSql("UPDATE dbo.Sys_PdfChapter SET ChapterTitle=N'" + SqlEsc(title)
                    + "' WHERE ChapterId='" + SqlEsc(affectedId) + "'");
            }
            else
            {
                // 新增：父级为目录树选中节点
                string parentId = this.trCatalog.SelectedNodeID;
                int level = 1;
                if (!string.IsNullOrEmpty(parentId))
                {
                    int parentLevel = SQLHelper.GetIntValue(
                        "SELECT ISNULL([Level],1) FROM dbo.Sys_PdfChapter WHERE ChapterId='" + SqlEsc(parentId) + "'");
                    level = parentLevel + 1;
                }
                int sort = SQLHelper.GetIntValue(
                    "SELECT ISNULL(MAX(SortNo),0) FROM dbo.Sys_PdfChapter WHERE BookId='" + SqlEsc(bookId) + "'") + 1;
                affectedId = NewId("CH");

                SQLHelper.ExecutSql(
                    "INSERT INTO dbo.Sys_PdfChapter (ChapterId, BookId, ParentChapterId, [Level], ChapterTitle, PageStart, PageEnd, Text, SortNo) VALUES ('"
                    + SqlEsc(affectedId) + "','" + SqlEsc(bookId) + "',"
                    + (string.IsNullOrEmpty(parentId) ? "NULL" : "'" + SqlEsc(parentId) + "'")
                    + "," + level + ",N'" + SqlEsc(title) + "',NULL,NULL,N''," + sort + ")");
            }

            this.WindowChapter.Hidden = true;
            InitTree(bookId);

            // 保持选中刚保存的章节并加载其正文（目录章节同样可编辑正文）
            this.trCatalog.SelectedNodeID = affectedId;
            PdfChapterDetail detail = PdfBookService.GetChapterContent(affectedId);
            this.htmlContent.Text = detail == null ? "" : (detail.Content ?? "");
            this.hfCurrentChapterId.Text = affectedId;
            this.lblProgress.Text = "章节已保存，正在编辑：" + (detail == null ? title : detail.Title);
        }

        /// <summary>
        /// 删除选中章节及其全部子章节。
        /// </summary>
        protected void btnDelChapter_Click(object sender, EventArgs e)
        {
            string chapterId = this.trCatalog.SelectedNodeID;
            if (string.IsNullOrEmpty(chapterId))
            {
                FineUIPro.Alert.Show("请先在目录中选择要删除的章节。");
                return;
            }

            string bookId = this.drpBook.SelectedValue;
            var all = PdfBookService.GetChapters(bookId);

            // 递归收集要删除的章节（自身+全部后代）
            var ids = new List<string> { chapterId };
            bool changed = true;
            while (changed)
            {
                changed = false;
                foreach (PdfChapter c in all)
                {
                    if (!ids.Contains(c.ChapterId) && ids.Contains(c.ParentChapterId ?? ""))
                    {
                        ids.Add(c.ChapterId);
                        changed = true;
                    }
                }
            }

            var sb = new StringBuilder();
            foreach (string id in ids)
            {
                if (sb.Length > 0)
                    sb.Append(",");
                sb.Append("'").Append(id.Replace("'", "''")).Append("'");
            }
            SQLHelper.ExecutSql("DELETE FROM dbo.Sys_PdfChapter WHERE ChapterId IN (" + sb + ")");

            InitTree(bookId);
            this.htmlContent.Text = "";
            this.hfCurrentChapterId.Text = "";
            this.lblProgress.Text = "章节已删除（含子章节 " + (ids.Count - 1) + " 个）。";
        }

        /// <summary>
        /// 关闭章节弹窗。
        /// </summary>
        protected void btnCloseChapter_Click(object sender, EventArgs e)
        {
            this.WindowChapter.Hidden = true;
        }
        #endregion

        #region 工具
        /// <summary>SQL 字符串转义。</summary>
        private static string SqlEsc(string s)
        {
            return (s ?? "").Replace("'", "''");
        }

        /// <summary>生成业务主键（前缀+时间+随机）。</summary>
        private static string NewId(string prefix)
        {
            return prefix + DateTime.Now.ToString("yyyyMMddHHmmss")
                + Guid.NewGuid().ToString("N").Substring(0, 4);
        }
        #endregion
    }
}