reactive-mail-server/backend/src/test/java/com/mailserver/service/SubmissionServiceTest.java

package com.mailserver.service;

import com.mailserver.domain.Attachment;
import com.mailserver.domain.User;
import com.mailserver.dto.SendRequest;
import jakarta.mail.Message;
import jakarta.mail.Session;
import jakarta.mail.internet.MimeMessage;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.io.TempDir;
import org.springframework.web.server.ResponseStatusException;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.List;
import java.util.Properties;

import static org.assertj.core.api.Assertions.assertThat;
import static org.assertj.core.api.Assertions.assertThatThrownBy;

class SubmissionServiceTest {

    @Test
    void addressesAreSplitLowercasedAndDeduplicated() {
        assertThat(SubmissionService.addresses(" Bob@Mail.test, alice@mail.test;bob@mail.test  carol@x.org "))
                .containsExactly("bob@mail.test", "alice@mail.test", "carol@x.org");
        assertThat(SubmissionService.addresses(null)).isEmpty();
        assertThat(SubmissionService.addresses("  ")).isEmpty();
    }

    @Test
    void malformedAddressIsRejected() {
        assertThatThrownBy(() -> SubmissionService.addresses("bob@mail.test, not-an-address"))
                .isInstanceOf(ResponseStatusException.class)
                .hasMessageContaining("not-an-address");
    }

    @Test
    void attachmentsGoIntoTheMessageAndComeBackOutOnDelivery(@TempDir Path dir) throws Exception {
        Path file = dir.resolve("report.pdf");
        Files.writeString(file, "%PDF-1.4 test");
        Attachment attachment = new Attachment();
        attachment.setFilename("Отчёт 2026.pdf");
        attachment.setContentType("application/pdf");
        attachment.setFilePath(file.toString());

        User user = new User();
        user.setEmail("admin@mail.test");
        user.setDisplayName("Admin");
        SendRequest request = new SendRequest();
        request.setSubject("Report");
        request.setBody("See the file");

        MimeMessage mime = SubmissionService.mime(user, List.of("bob@mail.test"), List.of("carol@mail.test"), request,
                List.of(attachment));
        ByteArrayOutputStream raw = new ByteArrayOutputStream();
        mime.writeTo(raw);

        MimeMessage parsed = new MimeMessage(Session.getInstance(new Properties()), new ByteArrayInputStream(raw.toByteArray()));
        assertThat(parsed.getRecipients(Message.RecipientType.CC)[0].toString()).isEqualTo("carol@mail.test");
        assertThat(LocalDelivery.addresses(parsed, Message.RecipientType.TO)).isEqualTo("bob@mail.test");
        assertThat(LocalDelivery.addresses(parsed, Message.RecipientType.CC)).isEqualTo("carol@mail.test");
        assertThat(LocalDelivery.body(parsed).text()).isEqualTo("See the file");
        List<LocalDelivery.FilePart> files = LocalDelivery.attachments(parsed);
        assertThat(files).hasSize(1);
        assertThat(files.get(0).name()).isEqualTo("Отчёт 2026.pdf");
        assertThat(files.get(0).contentType()).isEqualTo("application/pdf");
        assertThat(new String(files.get(0).bytes(), StandardCharsets.UTF_8)).isEqualTo("%PDF-1.4 test");
    }

    @Test
    void plainMessageHasNoAttachments() throws Exception {
        User user = new User();
        user.setEmail("admin@mail.test");
        SendRequest request = new SendRequest();
        request.setBody("Hi");
        MimeMessage mime = SubmissionService.mime(user, List.of("bob@mail.test"), List.of(), request, List.of());
        assertThat(LocalDelivery.attachments(mime)).isEmpty();
        assertThat(LocalDelivery.body(mime).text()).isEqualTo("Hi");
    }
}