package at.procon.dip.ingestion.adapter;

import at.procon.dip.classification.spi.DetectionResult;
import at.procon.dip.domain.access.DocumentAccessContext;
import at.procon.dip.domain.access.DocumentVisibility;
import at.procon.dip.domain.document.DocumentFamily;
import at.procon.dip.domain.document.DocumentStatus;
import at.procon.dip.domain.document.DocumentType;
import at.procon.dip.domain.document.RelationType;
import at.procon.dip.domain.document.SourceType;
import at.procon.dip.domain.document.entity.Document;
import at.procon.dip.domain.document.service.DocumentRelationService;
import at.procon.dip.domain.document.repository.DocumentSourceRepository;
import at.procon.dip.domain.document.service.command.CreateDocumentRelationCommand;
import at.procon.dip.ingestion.config.DipIngestionProperties;
import at.procon.dip.ingestion.dto.ImportedDocumentResult;
import at.procon.dip.ingestion.service.GenericDocumentImportService;
import at.procon.dip.ingestion.service.MailMessageExtractionService;
import at.procon.dip.ingestion.service.MailMetadataPersistenceService;
import at.procon.dip.ingestion.mail.MailImportIdentityResolver;
import at.procon.dip.ingestion.spi.IngestionResult;
import at.procon.dip.ingestion.spi.SourceDescriptor;
import at.procon.ted.service.attachment.ZipExtractionService;
import java.nio.file.Files;
import java.nio.file.Path;
import java.time.OffsetDateTime;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.UUID;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.ArgumentCaptor;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

import static org.junit.jupiter.api.Assertions.*;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.lenient;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

@ExtendWith(MockitoExtension.class)
class MailDocumentIngestionAdapterFileSystemTest {

    @Mock
    private GenericDocumentImportService importService;

    @Mock
    private DocumentRelationService relationService;

    @Mock
    private ZipExtractionService zipExtractionService;

    @Mock
    private MailMetadataPersistenceService mailMetadataPersistenceService;

    @Mock
    private DocumentSourceRepository documentSourceRepository;

    private MailDocumentIngestionAdapter adapter;
    private final List<SourceDescriptor> importedDescriptors = new ArrayList<>();

    @BeforeEach
    void setUp() {
        var properties = new DipIngestionProperties();
        properties.setEnabled(true);
        properties.setMailAdapterEnabled(true);
        properties.setMailImportBatchId("test-mail-batch");
        properties.setDefaultOwnerTenantKey("tenant-a");
        properties.setMailDefaultVisibility(DocumentVisibility.TENANT);

        MailMessageExtractionService extractionService = new MailMessageExtractionService();
        adapter = new MailDocumentIngestionAdapter(
                properties,
                importService,
                extractionService,
                relationService,
                zipExtractionService,
                new MailImportIdentityResolver(),
                mailMetadataPersistenceService,
                documentSourceRepository
        );

        when(zipExtractionService.canHandle(any(), any())).thenReturn(false);
        lenient().when(documentSourceRepository.findBySourceTypeAndExternalSourceId(any(), any())).thenReturn(java.util.Optional.empty());
        when(relationService.ensureRelation(any())).thenReturn(null);
        when(importService.importDocument(any())).thenAnswer(invocation -> {
            SourceDescriptor descriptor = invocation.getArgument(0);
            importedDescriptors.add(descriptor);
            return new ImportedDocumentResult(
                    buildDocumentFor(descriptor),
                    new DetectionResult(inferType(descriptor), inferFamily(descriptor), descriptor.mediaType(), "en", Map.of()),
                    List.of(),
                    false
            );
        });
    }

    @Test
    @DisplayName("Should ingest filesystem-loaded mail message with text and binary attachments")
    void shouldIngestFileSystemLoadedMailMessage() throws Exception {
        Path emlPath = Path.of("src", "test", "resources", "mail", "sample-message.eml");
        assertTrue(Files.exists(emlPath), "sample .eml test file must exist");
        byte[] mimeBytes = Files.readAllBytes(emlPath);

        SourceDescriptor sourceDescriptor = new SourceDescriptor(
                null,
                SourceType.MAIL,
                "fs-mail-001",
                emlPath.toAbsolutePath().toUri().toString(),
                emlPath.getFileName().toString(),
                "message/rfc822",
                mimeBytes,
                null,
                OffsetDateTime.parse("2026-03-18T15:27:59+01:00"),
                null,
                Map.of("source", "filesystem-test")
        );

        assertTrue(adapter.supports(sourceDescriptor));

        IngestionResult result = adapter.ingest(sourceDescriptor);

        assertEquals(3, result.documents().size(), "expected root mail document plus 2 attachment documents");
        assertTrue(result.warnings().isEmpty(), "mail import should not create warnings for the sample message");
        assertEquals(3, importedDescriptors.size(), "root + notes.txt + legacy.xls should be imported");

        SourceDescriptor root = importedDescriptors.get(0);
        assertEquals("message/rfc822", root.mediaType());
        assertEquals("sample-message.eml", root.fileName());
        assertNotNull(root.textContent());
        assertTrue(root.textContent().contains("Subject: Sample mail with filesystem-loaded attachments"));
        assertTrue(root.textContent().contains("Hello from the filesystem-backed sample message."));
        assertEquals(DocumentVisibility.TENANT, root.accessContext().visibility());
        assertNotNull(root.accessContext().ownerTenant());
        assertEquals("tenant-a", root.accessContext().ownerTenant().tenantKey());

        SourceDescriptor textAttachment = importedDescriptors.stream()
                .filter(d -> "notes.txt".equals(d.fileName()))
                .findFirst()
                .orElseThrow();
        assertEquals(SourceType.MAIL_ATTACHMENT, textAttachment.sourceType());
        assertEquals("text/plain", textAttachment.mediaType());
        assertNotNull(textAttachment.textContent(), "plain text attachment should expose preview text");
        assertTrue(textAttachment.textContent().contains("attachment notes"));

        SourceDescriptor binaryAttachment = importedDescriptors.stream()
                .filter(d -> "legacy.xls".equals(d.fileName()))
                .findFirst()
                .orElseThrow();
        assertEquals(SourceType.MAIL_ATTACHMENT, binaryAttachment.sourceType());
        assertNull(binaryAttachment.textContent(), "binary old Excel attachment must not be passed as text content");
        assertEquals("application/vnd.ms-excel", binaryAttachment.mediaType());
        assertNotNull(binaryAttachment.binaryContent());
        assertTrue(binaryAttachment.binaryContent().length > 0);

        ArgumentCaptor<CreateDocumentRelationCommand> relationCaptor = ArgumentCaptor.forClass(CreateDocumentRelationCommand.class);
        verify(relationService, times(2)).ensureRelation(relationCaptor.capture());
        assertTrue(relationCaptor.getAllValues().stream().allMatch(cmd -> cmd.relationType() == RelationType.ATTACHMENT_OF));
    }

    private Document buildDocumentFor(SourceDescriptor descriptor) {
        return Document.builder()
                .id(UUID.nameUUIDFromBytes((descriptor.sourceIdentifier() + ":" + descriptor.fileName()).getBytes()))
                .visibility(descriptor.accessContext() == null ? DocumentVisibility.PUBLIC : descriptor.accessContext().visibility())
                .documentType(inferType(descriptor))
                .documentFamily(inferFamily(descriptor))
                .status(DocumentStatus.RECEIVED)
                .title(descriptor.fileName())
                .mimeType(descriptor.mediaType())
                .dedupHash(Integer.toHexString((descriptor.sourceIdentifier() + descriptor.fileName()).hashCode()))
                .build();
    }

    private DocumentType inferType(SourceDescriptor descriptor) {
        if (descriptor.sourceType() == SourceType.MAIL && "message/rfc822".equals(descriptor.mediaType())) {
            return DocumentType.EMAIL;
        }
        String fileName = descriptor.fileName() == null ? "" : descriptor.fileName().toLowerCase();
        if (fileName.endsWith(".txt")) {
            return DocumentType.TEXT;
        }
        return DocumentType.GENERIC_BINARY;
    }

    private DocumentFamily inferFamily(SourceDescriptor descriptor) {
        return descriptor.sourceType() == SourceType.MAIL ? DocumentFamily.MAIL : DocumentFamily.GENERIC;
    }
}