using System;
using System.Text;
using System.Net.Mail;
using System.Net;
using System.IO;
using FastReport.Utils;


namespace FastReport.Export.Email
{
    /// <summary>
    /// Represents the email export.
    /// </summary>
    /// <remarks>
    /// In order to use this class, you need to set up at least the following properties:
    /// <see cref="Address"/>, <see cref="Subject"/>, <see cref="Account"/>. Use the <see cref="Export"/>
    /// property to choose the format of an attachment. If you leave it empty, the attachment will be
    /// in the .FRP format (FastReport prepared report). When you done with settings, call the
    /// <see cref="SendEmail"/> method to send an email.
    /// </remarks>
    /// <example>
    /// This example demonstrates the bare minimum required to send an email.
    /// <code>
    /// EmailExport export = new EmailExport();
    /// export.Account.Address = "my@address.net";
    /// export.Account.Host = "myhost";
    /// export.Address = "recipient@address.net";
    /// export.Subject = "Re: analysis report";
    /// // the report1 report must be prepared at this moment
    /// export.SendEmail(report1);
    /// </code>
    /// </example>
    public partial class EmailExport : IFRSerializable
    {
        #region Fields
        private string address;
        private string[] fcc;
        private string subject;
        private string messageBody;
        private string nameAttachmentFile;
        private ExportBase export;
        private EmailSettings account;
        private Report report;
        #endregion

        #region Properties
        /// <summary>
        /// Gets or sets the recipient's address.
        /// </summary>
        /// <remarks>
        /// This property must contain value in form "john@url.com".
        /// </remarks>
        public string Address
        {
            get { return address; }
            set { address = value; }
        }

        /// <summary>
        /// Gets or sets the carbon copy adresses.
        /// </summary>
        /// <remarks>
        /// This property must contain an array of values in form "john@url.com".
        /// </remarks>
        public string[] CC
        {
            get { return fcc; }
            set { fcc = value; }
        }

        /// <summary>
        /// Gets or sets the subject of the message.
        /// </summary>
        public string Subject
        {
            get { return subject; }
            set { subject = value; }
        }

        /// <summary>
        /// Gets or sets the message body.
        /// </summary>
        public string MessageBody
        {
            get { return messageBody; }
            set { messageBody = value; }
        }

        /// <summary>
        /// Gets or sets the name attachment file.
        /// </summary>
        public string NameAttachmentFile
        {
            get { return nameAttachmentFile; }
            set { nameAttachmentFile = value; }
        }

        /// <summary>
        /// Gets or sets the export filter which will be used to export a report.
        /// </summary>
        /// <remarks>
        /// Set this property to instance of any export filter. When you send the email, the report
        /// will be exported using that export filter. 
        /// <para/>By default, this property is set to <b>null</b>. In this case the report will be send
        /// in .FRP format.
        /// </remarks>
        public ExportBase Export
        {
            get { return export; }
            set { export = value; }
        }

        /// <summary>
        /// Gets the email account settings such as host, user name, password.
        /// </summary>
        public EmailSettings Account
        {
            get { return account; }
            set
            {
                if (value == null)
                    throw new ArgumentNullException("Account");
                account = value;
            }
        }

        /// <summary>
        /// Gets the parent Report object
        /// </summary>
        public Report Report
        {
            get { return report; }
        }
        #endregion

        #region Public Methods

        /// <summary>
        /// Sends an email.
        /// </summary>
        /// <param name="reports">Reports that will be sent as attachments.</param>
        /// <remarks>
        /// Before using this method, set up the following properties (it's a bare minimum):
        /// <see cref="Address"/>, <see cref="Subject"/>, <see cref="Account"/>.
        /// <para/>The report that you pass in this method must be prepared using the <b>Prepare</b> method.
        /// </remarks>
        public void SendEmail(params Report[] reports)
        {
            if (reports == null || reports.Length == 0)
                return;

            SmtpClient email = new SmtpClient();
            using (MailMessage message = new MailMessage(new MailAddress(Account.Address, Account.Name), new MailAddress(Address)))
            {
                if (CC != null)
                    foreach (string cc in CC)
                        message.CC.Add(new MailAddress(cc));

                message.Subject = Subject;
                message.SubjectEncoding = Encoding.UTF8;
                message.Body = MessageBody;
                message.BodyEncoding = Encoding.UTF8;

                foreach (Report report in reports)
                {
                    MemoryStream attachStream = new MemoryStream();

                    // export the report
                    if (Export != null)
                    {
                        Export.OpenAfterExport = false;
                        if (Export.HasMultipleFiles)
                            Export.ExportAndZip(report, attachStream);
                        else
                            Export.Export(report, attachStream);
                    }
                    else
                    {
                        report.PreparedPages.Save(attachStream);
                    }

                    // form an attachment name
                    string attachName = nameAttachmentFile != "" ? nameAttachmentFile : report.FileName;
                    if (String.IsNullOrEmpty(attachName))
                        attachName = "Report";
                    else
                        attachName = Path.GetFileNameWithoutExtension(attachName);

                    string extension = ".fpx";
                    if (Export != null)
                    {
                        extension = Export.FileFilter;
                        extension = extension.Substring(extension.LastIndexOf('.'));
                        if (Export.HasMultipleFiles)
                            extension = ".zip";
                    }

                    attachName += extension;
                    attachStream.Position = 0;

                    message.Attachments.Add(new Attachment(attachStream, attachName));
                }

                email.Host = Account.Host;
                email.Port = Account.Port;

                if (!String.IsNullOrEmpty(Account.UserName) && !String.IsNullOrEmpty(Account.Password))
                    email.Credentials = new NetworkCredential(Account.UserName, Account.Password);
                if (Account.EnableSSL)
                    email.EnableSsl = true;

                email.Send(message);
            }
        }

        /// <inheritdoc/>
        public void Serialize(FRWriter writer)
        {
            writer.WriteStr("Address", Address);
            writer.WriteStr("CC", CC == null ? "" : string.Join(";", CC));
            writer.WriteStr("Subject", Subject);
            writer.WriteStr("MessageBody", MessageBody);

            writer.WriteStr("AccountAddress", Account.Address);
            writer.WriteStr("AccountName", Account.Name);
            writer.WriteStr("AccountHost", Account.Host);
            writer.WriteInt("AccountPort", Account.Port);
            writer.WriteStr("AccountUserName", Crypter.EncryptString(Account.UserName));
            writer.WriteStr("AccountPassword", Crypter.EncryptString(Account.Password));
            writer.WriteStr("AccountMessageTemplate", Account.MessageTemplate);
            writer.WriteBool("AccountEnableSSL", Account.EnableSSL);
        }

        /// <inheritdoc/>
        public void Deserialize(FRReader reader)
        {
            Address = reader.ReadStr("Address");
            CC = reader.ReadStr("CC").Split(new string[] { ";" }, StringSplitOptions.RemoveEmptyEntries);
            Subject = reader.ReadStr("Subject");
            MessageBody = reader.ReadStr("MessageBody");

            Account.Address = reader.ReadStr("AccountAddress");
            Account.Name = reader.ReadStr("AccountName");
            Account.Host = reader.ReadStr("AccountHost");

            int port;
            if (int.TryParse(reader.ReadStr("AccountPort"), out port))
                Account.Port = port;

            Account.UserName = Crypter.DecryptString(reader.ReadStr("AccountUserName"));
            Account.Password = Crypter.DecryptString(reader.ReadStr("AccountPassword"));
            Account.MessageTemplate = reader.ReadStr("AccountMessageTemplate");
            Account.EnableSSL = reader.ReadBool("AccountEnableSSL");
        }
        #endregion

        /// <summary>
        /// Initializes a new instance of the <see cref="EmailExport"/> class with default settings.
        /// </summary>
        public EmailExport(Report report)
        {
            this.report = report;
            address = "";
            subject = "";
            messageBody = "";
            account = new EmailSettings();
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="EmailExport"/> class with default settings.
        /// </summary>
        public EmailExport()
        {
            address = "";
            subject = "";
            messageBody = "";
            account = new EmailSettings();
        }
    }
}