package com.condado.newsletter.service

import jakarta.mail.internet.InternetAddress
import jakarta.mail.internet.MimeMessage
import org.slf4j.LoggerFactory
import org.springframework.mail.javamail.JavaMailSender
import org.springframework.mail.javamail.MimeMessageHelper
import org.springframework.stereotype.Service

/**
 * Sends AI-generated emails via SMTP using Spring's [JavaMailSender].
 * Each email is sent as multipart (text/plain + text/html).
 */
@Service
class EmailSenderService(private val mailSender: JavaMailSender) {

    private val log = LoggerFactory.getLogger(javaClass)

    /**
     * Sends an email from a virtual entity to all configured recipients.
     *
     * @param from Sender email address (the virtual entity's email).
     * @param to   List of recipient email addresses.
     * @param subject Email subject line.
     * @param body Email body (may be plain text or simple HTML).
     */
    fun send(from: String, to: List<String>, subject: String, body: String) {
        log.info("Sending email from='$from' to=$to subject='$subject'")
        val message: MimeMessage = mailSender.createMimeMessage()
        val helper = MimeMessageHelper(message, true, "UTF-8")
        helper.setFrom(InternetAddress(from))
        helper.setTo(to.toTypedArray())
        helper.setSubject(subject)
        // Send as both plain text and HTML for maximum compatibility
        val plainText = body.replace(Regex("<[^>]+>"), "").trim()
        val htmlBody = if (body.contains(Regex("<[a-zA-Z]"))) body else "<pre>$body</pre>"
        helper.setText(plainText, htmlBody)
        mailSender.send(message)
        log.info("Email sent successfully from='$from' subject='$subject'")
    }
}