/**
 * Last Updated: 22/04/20221
 */
package com.example.controller;

import com.example.payload.UploadFileResponse;
import com.example.service.FileStorageService;
import com.example.usbtoken.Notary;
import com.example.usbtoken.UsbToken;
import com.example.usbtoken.UsbTokenMSCAPI;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.Resource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.support.ServletUriComponentsBuilder;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.itextpdf.text.Image;
import com.itextpdf.text.pdf.PdfStamper;
import com.itextpdf.text.pdf.security.ExternalDigest;
import com.itextpdf.text.pdf.security.ExternalSignature;
import com.itextpdf.text.pdf.security.MakeSignature;
import com.itextpdf.text.pdf.security.MakeSignature.CryptoStandard;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;

import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.Security;
import java.security.cert.Certificate;
import java.util.UUID;
import org.bouncycastle.jce.provider.BouncyCastleProvider;

/**
 *
 * @author Tuoi-cm File Controller
 * @version 1.0
 */
@CrossOrigin(maxAge = 3600)
@RestController
@RequestMapping(value = "/api/file")
public class FileController {

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

    @Autowired
    private FileStorageService fileStorageService;

    /**
     * Upload file and Sign PDF File
     *
     * @param file
     * @param llx
     * @param ury
     * @param lly
     * @param urx
     * @return UploadFileResponse
     */
    @PostMapping("/uploadFile")
    public UploadFileResponse uploadFile(
            @RequestParam("file") MultipartFile file,
            @RequestParam("llx") int llx,
            @RequestParam("lly") int lly,
            @RequestParam("urx") int urx,
            @RequestParam("ury") int ury,
            @RequestParam("checkUsbToken") String checkUsbToken,
            @RequestParam("indexAlias") int indexAlias,
            @RequestParam("mscapi") String mscapi) throws JsonMappingException, JsonProcessingException, IOException {
        UUID uuid = UUID.randomUUID();
        String uuidAsString = uuid.toString();
        String fileName = this.fileStorageService.storeFile(file, uuidAsString);

        //Location Save PDF File Signed.
        String fNameSign = "D:\\temp\\" + "Signed_" + fileName;
        String subStringFNameString = subStringFNameString = fNameSign.substring(8);

        if (file.getContentType().equals("application/pdf")) {
            if (checkUsbToken.equals("n")) {
                signPDF(convertMultiPartToFile(file), fNameSign, llx, lly, urx, ury);
            } else {
                if (mscapi.equals("mscapi")) {
                    UsbTokenMSCAPI mSCAPI = new UsbTokenMSCAPI("C:\\Windows\\System32\\eps2003csp11.dll");
                    byte[] signValue = mSCAPI.signText("text to sign...", "12345678");
                    boolean valid = new Notary().verifySignature("text to sign...".getBytes(), signValue,
                            mSCAPI.publicKey());
                    System.out.println("is valid?: " + valid);
                     if (valid) {
                        mSCAPI.multipleSignPdfUsbTokenMSCAPI(convertMultiPartToFile(file), fNameSign, llx, lly, urx, ury, checkUsbToken, indexAlias);
                    } else {
                        return new UploadFileResponse(fileName, file.getContentType(), file.getSize(),
                                fileName + " ERROR", 1);
                    }
                } else {
                    UsbToken usbToken = new UsbToken("C:\\Windows\\System32\\eps2003csp11.dll");
                    byte[] signValue = usbToken.signText("text to sign...", "12345678");
                    boolean valid = new Notary().verifySignature("text to sign...".getBytes(), signValue,
                            usbToken.publicKey("12345678"));
                    System.out.println("is valid?: " + valid);
                    if (valid) {
                        usbToken.multipleSignPdfUsbToken(convertMultiPartToFile(file), fNameSign, "12345678", llx, lly, urx, ury, checkUsbToken, indexAlias);
                    } else {
                        return new UploadFileResponse(fileName, file.getContentType(), file.getSize(),
                                fileName + " ERROR", 1);
                    }
                }
            }
        } else {
            return new UploadFileResponse(fileName, file.getContentType(), file.getSize(),
                    fileName + " is not a PDF File", 1);
        }
        String fileDownloadUri = ServletUriComponentsBuilder.fromCurrentContextPath()
                .path("/api/file/downloadFile/")
                .path(subStringFNameString)
                .toUriString();

        return new UploadFileResponse(subStringFNameString, fileDownloadUri,
                file.getContentType(), file.getSize(), "Upload File Successfully", 0);
    }

//    @PostMapping("/uploadMultipleFiles")
//    public List<UploadFileResponse> uploadMultipleFiles(@RequestParam("files") MultipartFile[] files) {
//        return Arrays.asList(files)
//                .stream()
//                .map(file -> uploadFile(file))
//                .collect(Collectors.toList());
//    }
    /**
     * Download file and Sign PDF File
     *
     * @param fileName, request
     * @return ResponseEntity
     */
    @GetMapping("/downloadFile/{fileName:.+}")
    public ResponseEntity<Resource> downloadFile(@PathVariable String fileName, HttpServletRequest request) {
        // Load file as Resource
        Resource resource = fileStorageService.loadFileAsResource(fileName);

        // Try to determine file's content type
        String contentType = null;
        try {
            contentType = request.getServletContext().getMimeType(resource.getFile().getAbsolutePath());
        } catch (IOException ex) {
            logger.info("Could not determine file type.");
        }

        // Fallback to the default content type if type could not be determined
        if (contentType == null) {
            contentType = "application/octet-stream";
        }

        return ResponseEntity.ok()
                .contentType(MediaType.parseMediaType(contentType))
                .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + resource.getFilename() + "\"")
                .body(resource);
    }

    /**
     * Sign PDF File
     *
     * @param file, fNameSign
     */
    public static void signPDF(File file, String fNameSign, int llx, int lly, int urx, int ury) {
        CryptoStandard subfilter = CryptoStandard.CMS;
        //Field Name PDF
        String fiedName = "";
        // Processing PDF File Here
        System.out.println("START");
        //The access path to pkcs12 key
        String fileP12 = "D:\\ProjectKyPDF\\vudp.p12";
        //Passhare
        String passFileP12 = "12345678";

        try {
            //Create KeyStore
            KeyStore ks = KeyStore.getInstance("pkcs12");
            //Download the p12 certificate in the store
            ks.load(new FileInputStream(fileP12), passFileP12.toCharArray());
            String alias = (String) ks.aliases().nextElement();
            //Get Private Key
            PrivateKey pk = (PrivateKey) ks.getKey(alias, passFileP12.toCharArray());
            //Certificate chain
            Certificate[] chain = ks.getCertificateChain(alias);
            //Check PDF File Sign
            com.itextpdf.text.pdf.PdfReader pdfReader = new com.itextpdf.text.pdf.PdfReader(file.getAbsolutePath());
            File outputFile = new File(fNameSign);
            //Read the source documentation
//            com.itextpdf.text.pdf.PdfReader pdfReader = new com.itextpdf.text.pdf.PdfReader(file.getAbsolutePath());
//            File outputFile = new File(fNameSign);

            //Create signature seal
            PdfStamper pdfStamper;
            pdfStamper = PdfStamper.createSignature(pdfReader, null, '\0', outputFile, true);
            //**
            com.itextpdf.text.pdf.PdfSignatureAppearance sap = pdfStamper.getSignatureAppearance();
            sap.setReason("Test SignPDF");
            sap.setLocation("VN");
            sap.setCertificationLevel(com.itextpdf.text.pdf.PdfSignatureAppearance.NOT_CERTIFIED);
            //The position of the stamp on the page (lower left of page 1)
            com.itextpdf.text.Rectangle rectangle = new com.itextpdf.text.Rectangle(llx, lly, urx, ury);
            UUID uuid = UUID.randomUUID();
            String uuidAsString = uuid.toString();
            fiedName = file.getName().equals(fNameSign.substring(file.getName().length())) ? "EDIT_" + uuidAsString : "NEW_" + uuidAsString;
            //Test
            System.out.println("File: " + file.getName());
            System.out.println("FNameSing: " + fNameSign.substring(file.getName().length()));
            sap.setVisibleSignature(rectangle, 1, fiedName);
            //
            //True allows to have 1 single reverse flase signature
//            pdfStamper.setFormFlattening();
            // Set the rendering mode for this signature.
            sap.setRenderingMode(com.itextpdf.text.pdf.PdfSignatureAppearance.RenderingMode.GRAPHIC_AND_DESCRIPTION);
            // Set the Image object to render when the rendering mode is set to RenderingMode.GRAPHIC
            // or RenderingMode.GRAPHIC_AND_DESCRIPTION.
            String img = "D:\\ProjectKyPDF\\signature-523237_960_720.jpg";
//            sap.setLayer2Font(new Font(Font.FontFamily.COURIER, 6));
            sap.setSignatureGraphic(Image.getInstance(img));
            sap.setImageScale(200);
            //Sgin
            //Provider 
            BouncyCastleProvider provider = new BouncyCastleProvider();
            Security.addProvider(provider);
            // Creating the signature
            ExternalSignature pks = new com.itextpdf.text.pdf.security.PrivateKeySignature(pk, "SHA512", BouncyCastleProvider.PROVIDER_NAME);
            ExternalDigest digest = new com.itextpdf.text.pdf.security.BouncyCastleDigest();
            MakeSignature.signDetached(sap, digest, pks, chain,
                    null, null, null, 0, subfilter);
            System.out.println("DONE!!!");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * Convert MultiPartFile to File
     *
     * @param file
     * @return File Converted
     */
    private File convertMultiPartToFile(MultipartFile file) throws IOException {
        File convFile = new File(file.getOriginalFilename());
        FileOutputStream fos = new FileOutputStream(convFile);
        fos.write(file.getBytes());
        fos.close();
        return convFile;
    }
}