package jnpf.fileStorage.dms;

import jnpf.dmsEntity.download.model.DmsFileDownloadTicket;
import jnpf.dmsEntity.preview.enums.DmsWatermarkTargetType;
import jnpf.dmsEntity.preview.model.DmsFilePreviewTicket;
import jnpf.dmsEntity.preview.model.DmsWatermarkSnapshot;
import jnpf.exception.DataException;
import jnpf.onlyoffice.PageWatermarkApi;
import jnpf.onlyoffice.PageWatermarkRequest;
import jnpf.util.JsonUtil;
import jnpf.util.TicketUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.BeanUtils;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.List;
import java.util.UUID;

@Service
public class DmsFileWatermarkService {
    private final DmsDocxWatermarkService docx;
    private final DmsImageWatermarkService image;
    private final DmsPdfWatermarkService pdf;
    private final PageWatermarkApi pageRenderer;
    private final java.util.function.Function<DmsFilePreviewTicket, String> sourceTicketIssuer;

    @Autowired
    public DmsFileWatermarkService(DmsDocxWatermarkService docx, DmsImageWatermarkService image,
                                   DmsPdfWatermarkService pdf, PageWatermarkApi pageRenderer) {
        this(docx, image, pdf, pageRenderer,
                ticket -> TicketUtil.createTicket(JsonUtil.getObjectToString(ticket), 180L));
    }

    DmsFileWatermarkService(DmsDocxWatermarkService docx, PageWatermarkApi pageRenderer,
                           java.util.function.Function<DmsFilePreviewTicket, String> sourceTicketIssuer) {
        this(docx, null, null, pageRenderer, sourceTicketIssuer);
    }

    DmsFileWatermarkService(DmsDocxWatermarkService docx, DmsImageWatermarkService image,
                            PageWatermarkApi pageRenderer,
                            java.util.function.Function<DmsFilePreviewTicket, String> sourceTicketIssuer) {
        this(docx, image, null, pageRenderer, sourceTicketIssuer);
    }

    DmsFileWatermarkService(DmsDocxWatermarkService docx, DmsImageWatermarkService image,
                            DmsPdfWatermarkService pdf, PageWatermarkApi pageRenderer,
                            java.util.function.Function<DmsFilePreviewTicket, String> sourceTicketIssuer) {
        this.docx = docx;
        this.image = image;
        this.pdf = pdf;
        this.pageRenderer = pageRenderer;
        this.sourceTicketIssuer = sourceTicketIssuer;
    }

    public byte[] apply(byte[] source, DmsFilePreviewTicket ticket) {
        return apply(source, ticket.getFileName(), ticket.getMimeType(), ticket.getWatermarks(), ticket);
    }

    public byte[] apply(byte[] source, DmsFileDownloadTicket ticket) {
        return apply(source, ticket.getFileName(), ticket.getMimeType(), ticket.getWatermarks(), ticket);
    }

    public byte[] loadAndApply(DmsImageWatermarkService.SourceReader sourceReader,
                               DmsFilePreviewTicket ticket) {
        return loadAndApply(sourceReader, ticket.getFileName(), ticket.getMimeType(),
                ticket.getWatermarks(), ticket);
    }

    public byte[] loadAndApply(DmsImageWatermarkService.SourceReader sourceReader,
                               DmsFileDownloadTicket ticket) {
        return loadAndApply(sourceReader, ticket.getFileName(), ticket.getMimeType(),
                ticket.getWatermarks(), ticket);
    }

    private byte[] loadAndApply(DmsImageWatermarkService.SourceReader sourceReader,
                                String fileName, String mimeType,
                                List<DmsWatermarkSnapshot> marks, Object sourceContext) {
        DmsWatermarkTargetType targetType = DmsWatermarkTargetType.from(fileName, mimeType);
        if (marks != null && !marks.isEmpty() && targetType == DmsWatermarkTargetType.IMAGE) {
            if (image == null) {
                throw new DataException("图片水印服务未配置");
            }
            return image.loadAndApply(sourceReader, fileName, mimeType, marks);
        }
        try {
            return apply(sourceReader.read(), fileName, mimeType, marks, sourceContext);
        } catch (DataException exception) {
            throw exception;
        } catch (Exception exception) {
            throw new DataException("读取 DMS 文件失败：" + exception.getMessage());
        }
    }

    private byte[] apply(byte[] source, String fileName, String mimeType,
                         List<DmsWatermarkSnapshot> marks, Object sourceContext) {
        if (marks == null || marks.isEmpty()) {
            return source;
        }
        DmsWatermarkTargetType targetType = DmsWatermarkTargetType.from(fileName, mimeType);
        if (targetType == DmsWatermarkTargetType.IMAGE) {
            if (image == null) {
                throw new DataException("图片水印服务未配置");
            }
            return image.apply(source, fileName, mimeType, marks);
        }
        if (targetType == DmsWatermarkTargetType.PDF) {
            if (pdf == null) {
                throw new DataException("PDF 水印服务未配置");
            }
            return pdf.apply(source, marks);
        }
        if (targetType != DmsWatermarkTargetType.DOCX) {
            throw new DataException("该文件格式不支持动态水印");
        }
        List<DmsWatermarkSnapshot> everyPage = new ArrayList<>();
        List<DmsWatermarkSnapshot> selectedPages = new ArrayList<>();
        for (DmsWatermarkSnapshot mark : marks) {
            (mark.getRenderPages() == null ? everyPage : selectedPages).add(mark);
        }
        if (selectedPages.isEmpty()) return docx.apply(source, everyPage);
        try {
            List<PageWatermarkRequest.Overlay> overlays = docx.pageOverlays(source, selectedPages);
            String prefix = "DMS_CUSTOM_" + UUID.randomUUID().toString().replace("-", "");
            // This delegated ticket is only sent server-to-server. Its source has no dynamic
            // watermarks, so Document Builder fetching it cannot recursively start another job.
            DmsFilePreviewTicket delegated = new DmsFilePreviewTicket();
            BeanUtils.copyProperties(sourceContext, delegated);
            delegated.setScope(DmsFilePreviewTicket.SCOPE);
            delegated.setWatermarks(new ArrayList<>());
            delegated.setExpiresAt(System.currentTimeMillis() + 180_000L);
            String sourceTicket = sourceTicketIssuer.apply(delegated);
            jnpf.base.ActionResult<byte[]> result = pageRenderer.render(new PageWatermarkRequest(delegated.getFileVersionId(),
                    sourceTicket, prefix, overlays));
            if (result == null || result.getCode() != 200 || result.getData() == null) {
                throw new DataException(result == null || result.getMsg() == null
                        ? "OnlyOffice 指定页水印生成失败" : result.getMsg());
            }
            int expected = overlays.stream().mapToInt(overlay -> overlay.getPages().size()).sum();
            byte[] placed = DmsPageWatermarkAnchors.fix(result.getData(), prefix, expected);
            // Header overlays do not change body pagination. Apply them after the page job so
            // its source can remain the immutable original without publishing a temporary file.
            return docx.apply(placed, everyPage);
        } catch (DataException e) {
            throw e;
        } catch (Exception e) {
            throw new DataException("生成指定各页的 DOCX 水印失败");
        }
    }
}