using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Runtime.InteropServices;
using Outlook = Microsoft.Office.Interop.Outlook;

namespace MiscTools
{
    /// <summary>
    /// 從 Outloook 郵件 .msg 檔擷取 HTML 內容
    /// </summary>
    public static class MsgHtmlExtrator
    {
        public static Dictionary<string, string> ConvToHtmls(string[] msgFilePaths)
        {
            //若 Outlook 已開啟，用現成的 Instance，否則新建
            var existing = Process.GetProcessesByName("OUTLOOK").Any();
            Outlook.Application outlookApp =
                existing ? 
                Marshal.GetActiveObject("Outlook.Application") as Outlook.Application:
                new Outlook.Application();
            var result = new Dictionary<string, string>();
            foreach (var msgFilePath in msgFilePaths)
            {
                var mail = (Outlook.MailItem)outlookApp.Session.OpenSharedItem(msgFilePath);
                result.Add(msgFilePath, mail.HTMLBody);
            }
            if (!existing) outlookApp.Quit();
            return result;
        }

        public static string ConvToHtml(string msgFilePath)
        {
            return ConvToHtmls(new string[] { msgFilePath }).First().Value;
        }

    }
}