/branches/0.15.x/src/MDownloader.Hostings/Providers/EasyShare/SiteBrowser.cs

using System;

using System.Collections.Generic;

using System.IO;

using System.Linq;

using System.Text;

using System.Text.RegularExpressions;

using Html.Engine.Browsing;

using Html.Engine.Domain;

using Html.Engine.Domain.Core;

using Html.Engine.Domain.Forms;

using MDownloader.Hostings.Common;

using MDownloader.Hostings.Core;

using MDownloader.Hostings.Exceptions;

using MDownloader.Hostings.Providers.EasyShare.Stages;

using Melon.Commons.Extensions;

using Html.Engine.Domain.Scripting;



namespace MDownloader.Hostings.Providers.EasyShare

{

    [HostingProvider]

    public sealed class SiteBrowser : HostingBase<SiteInfo>

    {

        #region Constants

        private static readonly string MainPage = @"http://www.easy-share.com/";

        private static readonly Regex GeneratedResourceRegex = new Regex("\"(?<link>http://www.easy-share.com/[0-9]+/[^\"]+)\"");

        private static readonly Regex DeleteLinkRegex = new Regex("http://www.easy-share.com/del/[0-9a-zA-Z]+.html");

        #endregion



        #region Overriden Members

        public override IHostingInfo GetInfo()

        {

            return SiteInfo.Instance;

        }



        protected override bool OnCanHandle(Uri link)

        {

            return link.Host.EndsWith("easy-share.com");

        }



        public override ResourceMetadata GetResourceMetadata(IDownloadContext context, IRetrievable target, DownloadSpecification specification)

        {

            var browser = context.CreateBrowser();

            this.ConfigureBrowser(browser, specification);



            var page = browser.NavigateTo(target.Link.ToString());

            this.CheckIfRemoved(page);



            var section = page.GetElementById("ucontent");

            var iName = section.GetDescendants<Literal>().First(x => x.GetOwner().ClassName == "px18 pb10");

            var iSize = iName.GetOwner().GetDescendants<Literal>().Last();



            var size = ResourceSizeHelper.FindSizeFromTheEnd(iSize.Content);

            var name = ResourceNameHelper.RemoveStringReferences(iName.Content);



            return new ResourceMetadata(name, size);

        }



        protected override ResourceData OnGetResourceData(IDownloadContext context, IRetrievable target, DownloadSpecification specification)

        {

            byte[] iCaptcha = null;

            string tCaptcha = null;



            var browser = context.CreateBrowser();

            this.ConfigureBrowser(browser, specification);



            var configuration = SiteInfo.Instance.GetConfiguration();

            var page = browser.NavigateTo(target.Link.ToString());



            // If user wants to use registered account we must log in first.

            if (configuration.Accounts.Preferences == AccountsSectionPart.UsagePreferences.Registered)

            {

                var account = configuration.Accounts.GetAccounts().RandomOrDefault();



                if (account != null)

                {

                    var loginStage = new LogInStage(page);



                    loginStage.SetCredentials(account.Username, account.Password);

                    loginStage.LogIn(browser);

                }

            }



            this.CheckIfRemoved(page);

            this.CheckIfBusy(page);



            context.Wait(TimeSpan.FromSeconds(20));



            var tRegex = new Regex("w\\s*=\\s*'(?<seconds>[0-9]+)'");

            var tQuery = from script in page.GetScripts()

                         where !String.IsNullOrEmpty(script.Content)

                         let tMatch = tRegex.Match(script.Content)

                         where tMatch.Success

                         select Int32.Parse(tMatch.Groups["seconds"].Value);



            context.Wait(TimeSpan.FromSeconds(tQuery.FirstOrDefault()));



            var cRegex = new Regex("u\\s*=\\s*'(?<url>[^']+)'");

            var cQuery = from script in page.GetScripts()

                         where !String.IsNullOrEmpty(script.Content)

                         let cMatch = cRegex.Match(script.Content)

                         where cMatch.Success

                         select cMatch.Groups["url"].Value;



            var cForm = browser.NavigateToAs<Form>(cQuery.First());

            var cFormId = new Uri(cForm.Action.Location).Segments[4].Trim('/');

            var cScript = browser.NavigateToAs<ScriptElement>(cQuery.First());

            var hRegex = new Regex("Recaptcha\\.create\\s*\\(\\s*\"(?<id>[^\"]+)\"");

            var hQuery = hRegex.Match(cScript.Content).Groups["id"].Value;



            var gUrl = String.Format("http://www.google.com/recaptcha/api/challenge?k={0}&ajax=1&cachestop=0.03379133495216441", hQuery);

            var iUrl = String.Empty;

            var iChallenge = String.Empty;



            using (var resource = browser.GetResourceData(gUrl, ResourceRange.Default))

            {

                var java = resource.OpenStream().ReadStringToEnd();

                var regex = new Regex("challenge\\s*:\\s*'(?<id>[^']*)'");

                var match = regex.Match(java);



                iChallenge = match.Groups["id"].Value;

                iUrl = String.Format(@"http://api.recaptcha.net/image?c={0}", iChallenge);

            }



            using (var resource = browser.GetResourceData(iUrl, ResourceRange.Default))

            {

                iCaptcha = resource.OpenStream().ReadBytesToEnd();

                tCaptcha = context.Recognize(CaptchaRecognitionMode.Default, iCaptcha, new CaptchaDescriptor());

            }

            

            using (var resource = browser.GetResourceData(new CaptchaRequest(cForm.Action.Location, cFormId, iChallenge, tCaptcha), this.GetResourceRange(specification)))

            {

                if (!resource.IsBinaryStream())

                    throw new BadPasscodeException(iCaptcha, tCaptcha, this.GetInfo());



                return new ResourceData(resource.OpenStream(), resource.Size, ResourceDataType.Binary);

            }

        }



        protected override Common.AccountInfo[] OnGetAvailableAccounts()

        {

            var accounts = from account in SiteInfo.Instance.GetConfiguration().Accounts.GetAccounts()

                           select new Common.AccountInfo(account.Id, account.Username);



            return accounts.ToArray();

        }



        protected override UploadResult OnUploadData(IDownloadContext context, IUploadable target, UploadSpecification specification)

        {

            var browser = context.CreateBrowser(TimeSpan.FromMinutes(2));

            this.ConfigureBrowser(browser, specification);



            var configuration = SiteInfo.Instance.GetConfiguration();

            var uploadPage = browser.NavigateTo(SiteBrowser.MainPage);

            var account = configuration.Accounts.GetAccounts().FirstOrDefault(x => x.Id == target.Account);



            if (account != null)

            {

                var loginStage = new LogInStage(uploadPage);



                loginStage.SetCredentials(account.Username, account.Password);

                loginStage.LogIn(browser);

            }



            var uploadStage = new UploadStage(uploadPage);

            var form = uploadStage.SetData(target.Name, target.Description, target.Size, target.OpenDataStream());



            using (var result = browser.GetResourceData(form, ResourceRange.Default))

            {

                var data = result.OpenStream().ReadStringToEnd();

                var link = SiteBrowser.GeneratedResourceRegex.Match(data).Groups["link"].Value;

                var delete = SiteBrowser.DeleteLinkRegex.Match(data).Value;



                return new UploadResult(new Uri(link), new Uri(delete));

            }

        }

        #endregion

        #region Private Members

        private void CheckIfRemoved(Page page)

        {

            if (page.GetElementById("tabCaptcha") == null)

                throw new NotFoundException();

        }



        private void CheckIfBusy(Page page)

        {

            var form = page.GetElementById("tabCaptcha");

            //var timer = page.GetElementById("freeTimer").GetChildren().First() as Literal;



            //if (form == null && timer != null)

            //    throw new PostponeException(Convert.ToInt32(ResourceSizeHelper.FindNumberFromTheBeginning(timer.Content)));



            //if (form == null)

            //    throw new PostponeException();

        }

        #endregion



        private class CaptchaRequest : ISubmittable

        {

            private readonly string location;

            private readonly string id;

            private readonly string challenge;

            private readonly string response;



            public CaptchaRequest(string location, string id, string challenge, string response)

            {

                this.location = location;

                this.id = id;

                this.challenge = challenge;

                this.response = response;

            }



            #region IResourceable Members

            public string Location

            {

                get { return this.location; }

            }



            public string Method

            {

                get { return @"POST"; }

            }



            public string Encoding

            {

                get { return @"application/x-www-form-urlencoded"; }

            }



            public ResourceParameter[] Parameters

            {

                get 

                {

                    return new[]

                    {

                        new ResourceParameter("id", this.id),

                        new ResourceParameter("recaptcha_challenge_field", this.challenge),

                        new ResourceParameter("recaptcha_response_field", this.response),

                    };

                }

            }



            ResourceParameter[] IResourceable.Headers

            {

                get { return new ResourceParameter[] { }; }

            }

            #endregion

        }

    }

}