using System.Globalization;
using MimeKit;
using SQLInsight.Notifications;

namespace SQLInsight.Reports;

/// <summary>Sends the management report as a PDF attachment through the same SMTP server as notifications.</summary>
public static class ReportMailer
{
    private static readonly CultureInfo Danish = CultureInfo.GetCultureInfo("da-DK");

    public static MimeMessage Build(EmailOptions smtp, IEnumerable<string> recipients, ReportData data, string periodName)
    {
        ArgumentNullException.ThrowIfNull(smtp);
        ArgumentNullException.ThrowIfNull(recipients);
        ArgumentNullException.ThrowIfNull(data);
        var message = new MimeMessage();
        message.From.Add(MailboxAddress.Parse(smtp.From));
        foreach (var to in recipients)
        {
            message.To.Add(MailboxAddress.Parse(to));
        }

        message.Subject = $"SQLInsight: Driftsrapport for {data.Organization}, {periodName}";
        var body = new BodyBuilder
        {
            TextBody = $"Driftsrapport for SQL Server, {periodName}.\n\n"
                + string.Join("\n", ManagementReport.SummarySentences(data).Select(s => "• " + s))
                + "\n\nDen fulde rapport er vedhæftet som PDF.\n\nSendt af SQLInsight Pro",
        };
        body.Attachments.Add($"driftsrapport-{data.From.ToString("yyyy-MM", CultureInfo.InvariantCulture)}.pdf", ManagementReport.Render(data), new ContentType("application", "pdf"));
        message.Body = body.ToMessageBody();
        return message;
    }

    public static string MonthName(DateTimeOffset firstOfMonth) => firstOfMonth.ToString("MMMM yyyy", Danish);

    public static Task SendAsync(EmailOptions smtp, MimeMessage message, CancellationToken cancellationToken) =>
        EmailChannel.SendMessageAsync(smtp, message, cancellationToken);
}