using System;
using System.Collections.Generic;
using System.Text;

namespace Biff8Excel.Excel
{
    /// <summary>
    /// 用于定义Excel页眉的内容及格式
    /// </summary>
    public class ExcelHeader: IDisposable 
    {
        Biff8Excel.Records.Header m_header;
        StringBuilder m_headerString;

        internal byte[] WriteRecord()
        {
            if (m_headerString.Length == 0)
            //if (m_headerString.Length == 0)
                return null ;

            //  make sure the string starts in one of the three sections
            //  in case we forget put it in the left section
            switch (m_headerString.ToString().Substring(0, 2))
            {
                case "&L":
                case "&C":
                case "&R":
                    break;
                default :
                    m_headerString.Append("&L");
                    break;
            }

            m_header.Head = Globals.GetUnicodeBytes(m_headerString.ToString());
            m_header.TextLen = (ushort)m_headerString.ToString().Length;
            return m_header.GetByte();
        }


        public void AddText(string sText)
        {
            if (sText.Length == 0)
                return;

            int pos;

            //Check fot the & character, needs to be duplicated in the string
            pos = 0;

            while(true)
            {
                pos = sText.IndexOf('&',pos);
                if (pos < 0)
                    break;

                //add an extra & character
                sText = sText.Substring(0,pos+1) + sText.Substring(pos);
                pos += 2;
            }

            m_headerString.Append(sText);
        }
     

        public void SetFont(string fontName)
        {
            SetFont(fontName, EnumFontStyle.Regular);
        }

        public void SetFont(string fontName, EnumFontStyle fontStyle)
        {
            m_headerString.Append("&" + (char)(0x22));          // Quotes 双引号
            m_headerString.Append(fontName + ",");

            string s ="";
            switch (fontStyle)
            {
                case EnumFontStyle.Regular:
                    s = "Regular";
                    break;
                case EnumFontStyle.Bold:
                    s = "Bold";
                    break;
                case EnumFontStyle.Italic:
                    s = "Italic";
                    break;
                case EnumFontStyle.BoldItalic:
                    s = "Bold Italic";
                    break;
            }

            m_headerString.Append(s + (char)(0x22));
        }

        public void SetFontSize(ushort fontSize)
        {
            m_headerString.Append("&" + fontSize.ToString());
        }

        public void StartLeftSection()
        {
            m_headerString.Append("&L");
        }

        public void StartCenterSection()
        {
            m_headerString.Append("&C");
        }

        public void StartRightSection()
        {
            m_headerString.Append("&R");
        }

        public void AddPageNumber()
        {
            m_headerString.Append("&P");
        }

        public void AddPageCount()
        {
            m_headerString.Append("&N");
        }

        public void AddCurrentDate()
        {
            m_headerString.Append("&D");
        }

        public void AddCurrentTime()
        {
            m_headerString.Append("&T");
        }

        public void AddSheetName()
        {
            m_headerString.Append("&A");
        }

        public void AddFileName()
        {
            m_headerString.Append("&F");
        }
       
        // This is the same for both on and off, but makes code clearer to define then separately
        public void SetUnderlineOn()
        {
            m_headerString.Append("&U");
        }

        public void SetUnderlineOff()
        {
            m_headerString.Append("&U");
        }

        public void SetDoubleUnderlineOn()
        {
            m_headerString.Append("&E");
        }

        public void SetDoubleUnderlineOff()
        {
            m_headerString.Append("&E");
        }

        public void SetStrikeOutOnOff()
        {
            m_headerString.Append("&S");
        }

        public void SetSuperScriptOutOnOff()
        {
            m_headerString.Append("&X");
        }

        public void SetSubScriptOutOnOff()
        {
            m_headerString.Append("&Y");
        }

        public ExcelHeader()
        {
            m_header = new Biff8Excel.Records.Header();
            m_headerString = new StringBuilder();
        }

        #region IDisposable 成员

        public void Dispose()
        {
            m_header = null;
            m_headerString = null;
        }

        #endregion
    }
}