using Amazon.Lambda.Core;
using Amazon.S3;
using Amazon.S3.Model;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Net.Http;
using System.Net.Mail;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Model.ResponseModel;
using classes;

public class PaymentReceiptService
{
    Logger logger;
    SesUser smtpUser;

    public ILambdaContext context { get; }

    public PaymentReceiptService(Logger logger, ILambdaContext context)
    {
        this.logger = logger;
        this.context = context;
        this.smtpUser = SecretsManager.GetSesUser();
    }
    public async Task<bool> GenerateReceipt(List<InfringementReceipt> infringements, double convenience, string email, string transactionId, string reference)
    {

        try
        {
            var html = GetReceiptHTMLString(infringements, convenience, reference);

            var httpClient = new HttpClient();
            httpClient.Timeout = TimeSpan.FromSeconds(Constants.TimeDefaultValue);
            var body = new Dictionary<string, string>
            {
                { "html", html}
            };

            var json = JsonConvert.SerializeObject(body);
            var content = new StringContent(json, Encoding.UTF8, "application/json");

            logger.LogMessage(context, "posting to" + Constants.PDF_MICRO_BASE_URL);
            var result = httpClient.PostAsync(Constants.PDF_MICRO_BASE_URL, content).Result;

            if (result.IsSuccessStatusCode)
            {
                var response = await result.Content.ReadAsStringAsync();
                var PdfMicro = JsonConvert.DeserializeObject<PdfMicro>(response);

                try
                {
                    logger.LogMessage(context, $"path returned : {PdfMicro.path} Linked email: {email} Filename: {PdfMicro.filename}");
                    logger.WriteLog("path", PdfMicro.path, $"Linked email:{email}", "TMT");
                    CancellationTokenSource source = new CancellationTokenSource();

                    // //small delay so that the pdf is created
                    await Task.Delay(TimeSpan.FromSeconds(1.5), source.Token);

                    var stream = await ReadFromS3(PdfMicro.filename);
                    var mailSentSuccess = SendMail(email, stream);
                    logger.LogMessage(context, "mail sent:" + mailSentSuccess.ToString());
                    if (!mailSentSuccess)
                    {
                        logger.LogMessage(context, $"mail not set: {email}. S3 Path: {PdfMicro.path}");
                        return false;
                    }
                }
                catch (Exception)
                {
                    //Send only hmtl if pdf server has issues
                    if (PdfMicro.path != null)
                    {
                        logger.LogMessage(context, $"cannot access: {PdfMicro.path} attachement for {email}");
                        logger.WriteLog(email, $"cannot access: {PdfMicro.path} attachement for {email}", "hmtl mail only", "TMT");

                        var mail = SendMail(email, html);
                        if (!mail)
                        {
                            logger.LogMessage(context, $"unable to send html mail to {email} for attachment {PdfMicro.path}");
                            logger.WriteLog("sending html mail", $"unable to send html mail to {email} for attachment {PdfMicro.path}", "test", "TMT");
                        }
                    }

                }

                return true;
            }
            else
            {
                logger.WriteLog(email, $"pdf server error status code: {result.StatusCode.ToString()}.", "Mail error", "TMT");
                logger.LogMessage(context, $"pdf server error status code: {result.StatusCode.ToString()}.");
                return false; //mail not sent;
            }
        }
        catch (Exception ex)
        {
            logger.WriteLog(email, "Error from PDF Server", ex.Message, "TMT");
            logger.LogMessage(context, "pdf not reached:" + ex.Message.ToString());
            return false;
        }

    }

    private bool SendMail(string email, MemoryStream pdfattachment)
    {

        SmtpClient client = new SmtpClient()
        {
            Host = Constants.TMT_MAIL_HOST,
            Port = 587,
            EnableSsl = true,
            DeliveryMethod = SmtpDeliveryMethod.Network,
            UseDefaultCredentials = false,
            Credentials = new NetworkCredential()
            {
                UserName = smtpUser.SMTP_Username,
                Password = smtpUser.SMTP_Password
            }
        };

        MailAddress from = new MailAddress(Constants.TMT_MAIL, "PMF");
        MailAddress to = new MailAddress(email);

        MailMessage message = new MailMessage();
        message.From = from;
        message.To.Add(to);
        message.Subject = "PMF Online Payment Receipt";
        message.IsBodyHtml = true;
        message.Body = "A payment has been made on PMF website";

        message.Attachments.Add(new Attachment(pdfattachment, "PMF_Payment_Receipt.pdf"));

        try
        {
            logger.WriteLog(email, "calling send mail", "mail", "TMT");
            client.Send(message);
            return true;
        }
        catch (Exception ex)
        {
            logger.WriteLog(email, "Smtp Mail error", ex.Message, "TMT");
            logger.LogMessage(context, $"function sending mail threw an exception + {email}");
            return false;
        }
    }
    private bool SendMail(string email, string body)
    {

        SmtpClient client = new SmtpClient()
        {
            Host = Constants.TMT_MAIL_HOST,
            Port = 587,
            EnableSsl = true,
            DeliveryMethod = SmtpDeliveryMethod.Network,
            UseDefaultCredentials = false,
            Credentials = new NetworkCredential()
            {
                UserName = smtpUser.SMTP_Username,
                Password = smtpUser.SMTP_Password
            }
        };

        MailAddress from = new MailAddress(Constants.TMT_MAIL, "PMF");
        MailAddress to = new MailAddress(email);
        MailMessage message = new MailMessage();
        message.From = from;
        message.To.Add(to);
        message.Subject = "PMF Online Payment Receipt";
        message.IsBodyHtml = true;
        message.Body = body;

        try
        {
            client.Send(message);
            return true;
        }
        catch (Exception ex)
        {
            logger.WriteLog(email, "SMTP error second attempt failed", ex.Message, "TMT");
            return false;
        }
    }

    private async Task<bool> SaveToS3(MemoryStream data, string email)
    {
        try
        {
            string keyName = DateTime.Now.ToString("yyyy-MM-dd h:mm:ss") + email; //find naming format
            using (var client = new AmazonS3Client(Amazon.RegionEndpoint.EUWest1))
            {
                var request = new PutObjectRequest
                {
                    InputStream = data,
                    BucketName = "tmt-pmf-prod-invoices",
                    Key = keyName,
                    ContentType = "application/pdf"
                };
                var response = await client.PutObjectAsync(request);
                if ((int)response.HttpStatusCode == 200)
                {
                    return true;
                }
            }

            return false;
        }
        catch (Exception)
        {
            return false;
        }
    }

    private async Task<MemoryStream> ReadFromS3(string bucketKey)
    {
        try
        {
            var client = new AmazonS3Client(Amazon.RegionEndpoint.EUWest1);
            GetObjectRequest request = new GetObjectRequest();
            logger.LogMessage(context, $"error reading from S3 bucket for key: {bucketKey}");
            request.BucketName = "tmt-pmf-prod-invoices";
            request.Key = bucketKey;
            GetObjectResponse response = await client.GetObjectAsync(request);
            var result = response.ResponseStream;

            MemoryStream pdfStream = new MemoryStream();
            result.CopyTo(pdfStream);

            pdfStream.Position = 0;

            logger.LogMessage(context, $"successfully read from s3 bucket");
            logger.WriteLog("S3", "Read from S3", bucketKey, "TMT");
            return pdfStream;
        }
        catch (Exception ex)
        {
            logger.LogMessage(context, $"error reading from S3: Error:{ex.Message}");
            logger.WriteLog("S3", "Read from S3", ex.Message, "TMT");
            throw ex;
        }

    }

    private string GetReceiptHTMLString(List<InfringementReceipt> paidInfringements, double convenience, string receiptNumber)
    {
        double total = default(double);
        string open = "{";
        string close = "}";
        var serverTime = DateTime.Now;
        var paymentdate = serverTime.AddHours(2).ToString("dd MMMM yyyy,  h:mm tt");
        string cssFilePath = Path.Combine(Directory.GetCurrentDirectory(), "Assets", "pmf_logo.svg");

        //avoid using external style sheets for the convertor. Include the css into html. An old design is in ./Assets/mystyle.css

        var sb = new StringBuilder();
        sb.Append(@$"
                        <html>
                            <head>
                                <style>
                                    @import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;600;700;900&display=swap');

                                        .header {open}
                                            float:left;
                                            padding-top: 5%;
                                            padding-left: 5%;
                                            width: 45%;
                                            overflow:hidden;
                                        {close}

                                        .header-right {open}
                                            padding-top: 5%;
                                            padding-right: 5%;
                                            
                                        {close}

                                        table {open}
                                            width: 90%;
                                            border-collapse: collapse;
                                            margin-top: -3%;
                                        {close}

                                        td, th {open}
                                            padding: 5px;
                                            font-size: 11px;
                                            text-align: center;
                                            color: #5f6f7c;
                                            font-family: 'Poppins', sans-serif;
                                            font-family:  Calibri;
                                            
                                        {close}

                                        table th {open}
                                            background-color: #6c757d;
                                            color: white;
                                            font-weight: 400;
                                            font-size: 11px;
                                            font-family:  Calibri;
                                            padding: 5px;
                                        {close}

                                        table, td, th {open}
                                            border: 1px solid #6c757d;
                                        {close}

                                        tr:nth-child(even) {open} background-color: #c4cacf;{close}
                                         tr:nth-child(odd) {open} background-color: #f2f2f2;{close}

                                        .total-column {open}
                                            text-align: right;
                                            color: white;
                                             font-weight: 600;
                                              background-color: #6c757d;
                                        {close}

                                        .total-label {open}
                                            text-align: left;
                                            color: white;
                                            font-weight: 600;
                                            background-color: #6c757d;
                                        {close}

                                        .line {open}
                                            width: 90%;
                                            margin-bottom: 5%;
                                        {close}

                                        .header-text {open}
                                            color: #b1aeae;
                                            font-family:  'Poppins', sans-serif;
                                            text-align: center;
                                        {close}

                                        h1 {open}
                                            font-size: 30px;
                                            font-family: 'Poppins', sans-serif;
                                        {close}

                                        .right {open}
                                            width: 35%;
                                            float: left;
                                            font-size: 11px;
                                            margin-top: -2%;
                                            color: grey;
                                        {close}

                                        .left {open}
                                            width: 55%;
                                            float: left;
                                            margin-left: 5%;
                                            margin-top: -2%;
                                            font-size: 11px;
                                            color: grey;
                                        {close}

                                        .black {open}
                                            color: black;
                                        {close}

                                        body {open}
                                            font-family: 'Poppins', sans-serif;
                                        {close}

                                        .footer {open}
                                                position: fixed;
                                                bottom: 0;
                                                width: 100%;
                                                text-align: center;
                                                margin: auto;
                                                font-weight: 600;
                                                font-size: 10px;
                                                color: #6c757d;
                                        {close}

                                        .foo {open}
                                            font-weight: 600;
                                        {close}
                                </style>
                            </head>
                            <body>
                                <div class='main'>
                                    <div style='width: 23%; float:left; margin-left: 5% '>
                                          <img src='https://master.d39rr3ejryd4rk.amplifyapp.com/static/media/pmf_logo_pos_1.447e4375.svg' style = 'margin: auto; margin-top:20%'>
                                    </div>
                                    <div style='width: 55%; float:right;'>
                                        <h1 class='header-text'>Payment Receipt</h1>
                                    </div>
                                   <div class = 'left'> 
                                        <p><b class ='black'> Payment Enquiries:</b> 010 500 0077 or payment@paymyfines.co.za </p> <p><b class ='black'> Other Enquiries:</b> help@paymyfines.co.za </p> 
                                   </div>
                                   <div class = 'right'>
                                        <p><b class ='black'> Date: </b>  {paymentdate}</p><p><b class ='black'> Receipt Number:</b> <span  style='float:right; width: 48%'> {receiptNumber} </span></p>
                                   </div>
                                </div>
                                <hr class='line'>
                                <table align='center'>
                                    <tr>
                                        <th style='text-align:left'>INFRINGEMENT NUMBER</th>
                                        <th>ID NUMBER</th>
                                        <th>VEHICLE REGISTRATION</th>
                                        <th style='text-align:right'>AMOUNT</th>
                                    </tr>");

        foreach (var infringement in paidInfringements)
        {
            var InfringementAmount = (infringement.Amount - convenience).ToString();
            sb.AppendFormat(@"<tr>
                                    <td style='text-align:left'>{0}</td>
                                    <td>{1}</td>
                                    <td>{2}</td>
                                    <td style='text-align:right'>R {3}</td>
                                </tr>", infringement.Infringement, infringement.IdNumber, infringement.VechicleRegistration, InfringementAmount);
            total = total + (infringement.Amount - convenience);
        }

        double totalConvenience = convenience * paidInfringements.Count;
        total = total + totalConvenience;

        sb.Append(@$"
                                <tr>
                                    <td style ='text-align: left;' colspan='3'>Convenience Fee(R{convenience} per Infringement)</td>
                                    <td style ='text-align: right;' style='text-align:right'>R {totalConvenience} </td>
                                </tr>
                                <tr>
                                    <td class ='total-label' colspan='3'> TOTAL  </td>
                                    <td class ='total-column' style='text-align:right'>R {total} </td>
                                </tr>
                            </body>
                        </html>");

        sb.Append(@"
                                </table>
                                <div class='footer'>
                                    <hr style = 'width: 90%'>
                                         <p> <span style= 'float: center; margin-bottom: 1%'> Paymyfines, PO BOX 234, Century City, Cape Town, 7446, South Africa </span> </p>
                                </div>
                            </body>
                        </html>");

        return sb.ToString();
    }
}