using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Text.RegularExpressions;
using System.Web;
using System.Web.Caching;
using System.Web.Configuration;
using OnlineEditorsExampleMVC.Models;

namespace OnlineEditorsExampleMVC.Helpers
{
    public class DocManagerHelper
    {
        public static long MaxFileSize
        {
            get
            {
                long size;
                long.TryParse(WebConfigurationManager.AppSettings["filesize-max"], out size);
                return size > 0 ? size : 5 * 1024 * 1024;
            }
        }

        public static List<string> FileExts
        {
            get { return ViewedExts.Concat(EditedExts).Concat(ConvertExts).ToList(); }
        }

        public static List<string> ViewedExts
        {
            get { return (WebConfigurationManager.AppSettings["files.docservice.viewed-docs"] ?? "").Split(new char[] { '|', ',' }, StringSplitOptions.RemoveEmptyEntries).ToList(); }
        }

        public static List<string> EditedExts
        {
            get { return (WebConfigurationManager.AppSettings["files.docservice.edited-docs"] ?? "").Split(new char[] { '|', ',' }, StringSplitOptions.RemoveEmptyEntries).ToList(); }
        }

        public static List<string> ConvertExts
        {
            get { return (WebConfigurationManager.AppSettings["files.docservice.convert-docs"] ?? "").Split(new char[] { '|', ',' }, StringSplitOptions.RemoveEmptyEntries).ToList(); }
        }

        public static string CurUserHostAddress(string userAddress = null)
        {
            return Regex.Replace(userAddress ?? HttpContext.Current.Request.UserHostAddress, "[^0-9a-zA-Z.=]", "_");
        }

        public static string StoragePath(string fileName, string userAddress = null)
        {
            var directory = HttpRuntime.AppDomainAppPath + WebConfigurationManager.AppSettings["storage-path"] + CurUserHostAddress(userAddress) + "\\";
            if (!Directory.Exists(directory))
            {
                Directory.CreateDirectory(directory);
            }
            return directory + fileName;
        }

        public static string GetCorrectName(string fileName)
        {
            var baseName = Path.GetFileNameWithoutExtension(fileName);
            var ext = Path.GetExtension(fileName);
            var name = baseName + ext;

            for (var i = 1; File.Exists(StoragePath(name)); i++)
            {
                name = baseName + " (" + i + ")" + ext;
            }
            return name;
        }

        public static string CreateDemo(string fileExt)
        {
            var demoName = "sample." + fileExt;

            var fileName = GetCorrectName(demoName);

            File.Copy(HttpRuntime.AppDomainAppPath + "app_data\\" + demoName, StoragePath(fileName));

            return fileName;
        }

        public static string GetFileUri(string fileName)
        {
            var uri = new UriBuilder(HttpContext.Current.Request.Url)
                {
                    Path = HttpRuntime.AppDomainAppVirtualPath + "/App_Data/"
                           + CurUserHostAddress() + "/"
                           + fileName,
                    Query = ""
                };

            if (HaveExternalIP())
            {
                return uri.ToString();
            }

            return GetExternalUri(uri.ToString());
        }

        public static string GetCallback(string fileName)
        {
            var callbackUrl = new UriBuilder(HttpContext.Current.Request.Url)
            {
                Path =
                    HttpRuntime.AppDomainAppVirtualPath
                    + (HttpRuntime.AppDomainAppVirtualPath.EndsWith("/") ? "" : "/")
                    + "webeditor.ashx",
                Query = "type=track"
                        + "&userAddress=" + HttpUtility.UrlEncode(HttpContext.Current.Request.UserHostAddress)
                        + "&fileName=" + HttpUtility.UrlEncode(fileName)
            };
            return callbackUrl.ToString();
        }

        private static bool? _haveExternalIP;

        public static bool HaveExternalIP()
        {
            if (!_haveExternalIP.HasValue)
            {
                string convertUri;
                try
                {
                    var uri = new UriBuilder(HttpContext.Current.Request.Url)
                    {
                        Path = HttpRuntime.AppDomainAppVirtualPath + "/App_Data/demo.docx",
                        Query = ""
                    };
                    var fileUri = uri.ToString();

                    ServiceConverter.GetConvertedUri(fileUri, "docx", "docx", Guid.NewGuid().ToString(), false, out convertUri);
                }
                catch
                {
                    convertUri = string.Empty;
                }

                _haveExternalIP = !string.IsNullOrEmpty(convertUri);
            }

            return _haveExternalIP.Value;
        }

        public static string GetExternalUri(string localUri)
        {
            try
            {
                var uri = HttpRuntime.Cache.Get(localUri) as string;
                if (string.IsNullOrEmpty(uri))
                {

                    var webRequest = WebRequest.Create(localUri);
                    using (var response = webRequest.GetResponse())
                    using (var responseStream = response.GetResponseStream())
                    {
                        var key = ServiceConverter.GenerateRevisionId(localUri);
                        uri = ServiceConverter.GetExternalUri(responseStream, response.ContentLength, response.ContentType, key);
                    }
                    HttpRuntime.Cache.Insert(localUri, uri, null, DateTime.Now.Add(TimeSpan.FromMinutes(2)), Cache.NoSlidingExpiration);
                }
                return uri;
            }
            catch (Exception)
            {

            }
            return localUri;
        }

        public static string GetInternalExtension(FileUtility.FileType fileType)
        {
            switch (fileType)
            {
                case FileUtility.FileType.Text:
                    return ".docx";
                case FileUtility.FileType.Spreadsheet:
                    return ".xlsx";
                case FileUtility.FileType.Presentation:
                    return ".pptx";
                default:
                    return ".docx";
            }
        }
    }
}