using System.Diagnostics.CodeAnalysis;
using System.Text.Json;
using MailKit.Net.Smtp;
using MailKit.Security;
using MimeKit;

namespace InnovEnergy.Lib.Mailer;

public static class Mailer
{
    [UnconditionalSuppressMessage("Trimming", "IL2026:Members annotated with 'RequiresUnreferencedCodeAttribute' require dynamic access otherwise can break functionality when trimming application code", Justification = "<Pending>")]
    public static async Task Send(string recipientName, string recipientEmailAddress, string subject, string body)
    {
        var config = await ReadMailerConfig();
        
        Console.WriteLine("=============== SMTP CONFIG LOADED ==============");
        Console.WriteLine($"Config full path: {Path.GetFullPath(MailerConfig.DefaultFile)}");
        Console.WriteLine($"SMTP host: {config!.SmtpServerUrl}");
        Console.WriteLine($"SMTP port: {config.SmtpPort}");
        Console.WriteLine($"SMTP username: {config.SmtpUsername}");
        Console.WriteLine($"Sender: {config.SenderName} <{config.SenderAddress}>");
        Console.WriteLine("==================================================");


        var from = new MailboxAddress(config!.SenderName, config.SenderAddress);
        var to   = new MailboxAddress(recipientName, recipientEmailAddress);

        var msg = new MimeMessage
        {
            From    = { from },
            To      = { to },
            Subject = subject,
            Body    = new TextPart("plain") { Text = body }
        };

        using var smtp = new SmtpClient();

        try
        {
            await smtp.ConnectAsync(config.SmtpServerUrl, config.SmtpPort, SecureSocketOptions.StartTls);
            await smtp.AuthenticateAsync(config.SmtpUsername, config.SmtpPassword);
            await smtp.SendAsync(msg);
            await smtp.DisconnectAsync(true);
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
            throw; // keep while testing
        }
    }

    [RequiresUnreferencedCode("Calls System.Text.Json.JsonSerializer.DeserializeAsync<TValue>(Stream, JsonSerializerOptions, CancellationToken)")]
    private static async Task<MailerConfig?> ReadMailerConfig()
    {
        await using var fileStream = File.OpenRead(MailerConfig.DefaultFile);
        return await JsonSerializer.DeserializeAsync<MailerConfig>(fileStream);
    }
}