package stirling.software.SPDF.controller.api.security;

import java.awt.Color;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.List;

import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDPageContentStream;
import org.apache.pdfbox.pdmodel.common.PDRectangle;
import org.apache.pdfbox.pdmodel.graphics.image.LosslessFactory;
import org.apache.pdfbox.pdmodel.graphics.image.PDImageXObject;
import org.apache.pdfbox.rendering.ImageType;
import org.apache.pdfbox.rendering.PDFRenderer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import io.swagger.v3.oas.annotations.Operation;
import io.swagger.v3.oas.annotations.tags.Tag;

import stirling.software.SPDF.model.PDFText;
import stirling.software.SPDF.model.api.security.RedactPdfRequest;
import stirling.software.SPDF.pdf.TextFinder;
import stirling.software.SPDF.utils.WebResponseUtils;

@RestController
@RequestMapping("/api/v1/security")
@Tag(name = "Security", description = "Security APIs")
public class RedactController {

    private static final Logger logger = LoggerFactory.getLogger(RedactController.class);

    @PostMapping(value = "/auto-redact", consumes = "multipart/form-data")
    @Operation(
            summary = "Redacts listOfText in a PDF document",
            description =
                    "This operation takes an input PDF file and redacts the provided listOfText. Input:PDF, Output:PDF, Type:SISO")
    public ResponseEntity<byte[]> redactPdf(@ModelAttribute RedactPdfRequest request)
            throws Exception {
        MultipartFile file = request.getFileInput();
        String listOfTextString = request.getListOfText();
        boolean useRegex = request.isUseRegex();
        boolean wholeWordSearchBool = request.isWholeWordSearch();
        String colorString = request.getRedactColor();
        float customPadding = request.getCustomPadding();
        boolean convertPDFToImage = request.isConvertPDFToImage();

        System.out.println(listOfTextString);
        String[] listOfText = listOfTextString.split("\n");
        byte[] bytes = file.getBytes();
        PDDocument document = PDDocument.load(new ByteArrayInputStream(bytes));

        Color redactColor;
        try {
            if (!colorString.startsWith("#")) {
                colorString = "#" + colorString;
            }
            redactColor = Color.decode(colorString);
        } catch (NumberFormatException e) {
            logger.warn("Invalid color string provided. Using default color BLACK for redaction.");
            redactColor = Color.BLACK;
        }

        for (String text : listOfText) {
            text = text.trim();
            System.out.println(text);
            TextFinder textFinder = new TextFinder(text, useRegex, wholeWordSearchBool);
            List<PDFText> foundTexts = textFinder.getTextLocations(document);
            redactFoundText(document, foundTexts, customPadding, redactColor);
        }

        if (convertPDFToImage) {
            PDDocument imageDocument = new PDDocument();
            PDFRenderer pdfRenderer = new PDFRenderer(document);
            for (int page = 0; page < document.getNumberOfPages(); ++page) {
                BufferedImage bim = pdfRenderer.renderImageWithDPI(page, 300, ImageType.RGB);
                PDPage newPage = new PDPage(new PDRectangle(bim.getWidth(), bim.getHeight()));
                imageDocument.addPage(newPage);
                PDImageXObject pdImage = LosslessFactory.createFromImage(imageDocument, bim);
                PDPageContentStream contentStream = new PDPageContentStream(imageDocument, newPage);
                contentStream.drawImage(pdImage, 0, 0);
                contentStream.close();
            }
            document.close();
            document = imageDocument;
        }

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        document.save(baos);
        document.close();

        byte[] pdfContent = baos.toByteArray();
        return WebResponseUtils.bytesToWebResponse(
                pdfContent,
                file.getOriginalFilename().replaceFirst("[.][^.]+$", "") + "_redacted.pdf");
    }

    private void redactFoundText(
            PDDocument document, List<PDFText> blocks, float customPadding, Color redactColor)
            throws IOException {
        var allPages = document.getDocumentCatalog().getPages();

        for (PDFText block : blocks) {
            var page = allPages.get(block.getPageIndex());
            PDPageContentStream contentStream =
                    new PDPageContentStream(
                            document, page, PDPageContentStream.AppendMode.APPEND, true, true);
            contentStream.setNonStrokingColor(redactColor);
            float padding = (block.getY2() - block.getY1()) * 0.3f + customPadding;
            PDRectangle pageBox = page.getBBox();
            contentStream.addRect(
                    block.getX1(),
                    pageBox.getHeight() - block.getY1() - padding,
                    block.getX2() - block.getX1(),
                    block.getY2() - block.getY1() + 2 * padding);
            contentStream.fill();
            contentStream.close();
        }
    }
}
