use crate::app_config::AppConfig;
use lettre::message::header::ContentType;
use lettre::transport::smtp::authentication::Credentials;
use lettre::{Message, SmtpTransport, Transport};
use std::fmt::Display;

pub async fn send_mail<D: Display>(to: &str, subject: &str, body: D) -> anyhow::Result<()> {
    let conf = AppConfig::get();

    let email = Message::builder()
        .from(conf.mail_sender.parse()?)
        .to(to.parse()?)
        .subject(subject)
        .header(ContentType::TEXT_PLAIN)
        .body(body.to_string())?;

    let mut mailer = match conf.smtp_tls {
        true => SmtpTransport::relay(&conf.smtp_relay)?,
        false => SmtpTransport::builder_dangerous(&conf.smtp_relay),
    }
    .port(conf.smtp_port);

    if let (Some(username), Some(password)) = (&conf.smtp_username, &conf.smtp_password) {
        mailer = mailer.credentials(Credentials::new(username.to_string(), password.to_string()))
    }

    let mailer = mailer.build();

    mailer.send(&email)?;
    log::debug!("A mail was sent to {} (subject = {})", to, subject);

    Ok(())
}