import {
  DocumentStatus,
  EnvelopeType,
  RecipientRole,
  SigningStatus,
  WebhookTriggerEvents,
} from '@prisma/client';
import { nanoid } from 'nanoid';
import path from 'node:path';
import { PDFDocument } from 'pdf-lib';

import PostHogServerClient from '@documenso/lib/server-only/feature-flags/get-post-hog-server-client';
import { DOCUMENT_AUDIT_LOG_TYPE } from '@documenso/lib/types/document-audit-logs';
import { createDocumentAuditLogData } from '@documenso/lib/utils/document-audit-logs';
import { prisma } from '@documenso/prisma';
import { signPdf } from '@documenso/signing';

import {
  ZWebhookDocumentSchema,
  mapEnvelopeToWebhookDocumentPayload,
} from '../../types/webhook-payload';
import type { RequestMetadata } from '../../universal/extract-request-metadata';
import { getFileServerSide } from '../../universal/upload/get-file.server';
import { putPdfFileServerSide } from '../../universal/upload/put-file.server';
import { fieldsContainUnsignedRequiredField } from '../../utils/advanced-fields-helpers';
import {
  type EnvelopeIdOptions,
  mapSecondaryIdToDocumentId,
  unsafeBuildEnvelopeIdQuery,
} from '../../utils/envelope';
import { getAuditLogsPdf } from '../htmltopdf/get-audit-logs-pdf';
import { getCertificatePdf } from '../htmltopdf/get-certificate-pdf';
import { addRejectionStampToPdf } from '../pdf/add-rejection-stamp-to-pdf';
import { flattenAnnotations } from '../pdf/flatten-annotations';
import { flattenForm } from '../pdf/flatten-form';
import { insertFieldInPDF } from '../pdf/insert-field-in-pdf';
import { legacy_insertFieldInPDF } from '../pdf/legacy-insert-field-in-pdf';
import { normalizeSignatureAppearances } from '../pdf/normalize-signature-appearances';
import { getTeamSettings } from '../team/get-team-settings';
import { triggerWebhook } from '../webhooks/trigger/trigger-webhook';
import { sendCompletedEmail } from './send-completed-email';

export type SealDocumentOptions = {
  id: EnvelopeIdOptions;
  sendEmail?: boolean;
  isResealing?: boolean;
  requestMetadata?: RequestMetadata;
};

export const sealDocument = async ({
  id,
  sendEmail = true,
  isResealing = false,
  requestMetadata,
}: SealDocumentOptions) => {
  const envelope = await prisma.envelope.findFirstOrThrow({
    where: unsafeBuildEnvelopeIdQuery(id, EnvelopeType.DOCUMENT),
    include: {
      envelopeItems: {
        select: {
          id: true,
          documentData: true,
        },
        include: {
          field: {
            include: {
              signature: true,
            },
          },
        },
      },
      documentMeta: true,
      recipients: {
        where: {
          role: {
            not: RecipientRole.CC,
          },
        },
      },
    },
  });

  // Todo: Envelopes
  const envelopeItemToSeal = envelope.envelopeItems[0];

  // Todo: Envelopes
  if (envelope.envelopeItems.length !== 1 || !envelopeItemToSeal) {
    throw new Error(`Document ${envelope.id} needs exactly 1 envelope item`);
  }

  const legacyDocumentId = mapSecondaryIdToDocumentId(envelope.secondaryId);
  const documentData = envelopeItemToSeal.documentData;
  const fields = envelopeItemToSeal.field; // Todo: Envelopes - This only takes in the first envelope item fields.
  const recipients = envelope.recipients;

  const settings = await getTeamSettings({
    userId: envelope.userId,
    teamId: envelope.teamId,
  });

  // Determine if the document has been rejected by checking if any recipient has rejected it
  const rejectedRecipient = recipients.find(
    (recipient) => recipient.signingStatus === SigningStatus.REJECTED,
  );

  const isRejected = Boolean(rejectedRecipient);

  // Get the rejection reason from the rejected recipient
  const rejectionReason = rejectedRecipient?.rejectionReason ?? '';

  // If the document is not rejected, ensure all recipients have signed
  if (
    !isRejected &&
    recipients.some((recipient) => recipient.signingStatus !== SigningStatus.SIGNED)
  ) {
    throw new Error(`Envelope ${envelope.id} has unsigned recipients`);
  }

  // Skip the field check if the document is rejected
  if (!isRejected && fieldsContainUnsignedRequiredField(fields)) {
    throw new Error(`Document ${envelope.id} has unsigned required fields`);
  }

  if (isResealing) {
    // If we're resealing we want to use the initial data for the document
    // so we aren't placing fields on top of eachother.
    documentData.data = documentData.initialData;
  }

  // !: Need to write the fields onto the document as a hard copy
  const pdfData = await getFileServerSide(documentData);

  const certificateData = settings.includeSigningCertificate
    ? await getCertificatePdf({
        documentId: legacyDocumentId,
        language: envelope.documentMeta.language,
      }).catch((e) => {
        console.log('Failed to get certificate PDF');
        console.error(e);

        return null;
      })
    : null;

  const auditLogData = settings.includeAuditLog
    ? await getAuditLogsPdf({
        documentId: legacyDocumentId,
        language: envelope.documentMeta.language,
      }).catch((e) => {
        console.log('Failed to get audit logs PDF');
        console.error(e);

        return null;
      })
    : null;

  const doc = await PDFDocument.load(pdfData);

  // Normalize and flatten layers that could cause issues with the signature
  normalizeSignatureAppearances(doc);
  await flattenForm(doc);
  flattenAnnotations(doc);

  // Add rejection stamp if the document is rejected
  if (isRejected && rejectionReason) {
    await addRejectionStampToPdf(doc, rejectionReason);
  }

  if (certificateData) {
    const certificate = await PDFDocument.load(certificateData);

    const certificatePages = await doc.copyPages(certificate, certificate.getPageIndices());

    certificatePages.forEach((page) => {
      doc.addPage(page);
    });
  }

  if (auditLogData) {
    const auditLog = await PDFDocument.load(auditLogData);

    const auditLogPages = await doc.copyPages(auditLog, auditLog.getPageIndices());

    auditLogPages.forEach((page) => {
      doc.addPage(page);
    });
  }

  for (const field of fields) {
    envelope.useLegacyFieldInsertion
      ? await legacy_insertFieldInPDF(doc, field)
      : await insertFieldInPDF(doc, field);
  }

  // Re-flatten post-insertion to handle fields that create arcoFields
  await flattenForm(doc);

  const pdfBytes = await doc.save();

  const pdfBuffer = await signPdf({ pdf: Buffer.from(pdfBytes) });

  // Todo: Envelopes use EnvelopeItem title instead.
  const { name } = path.parse(envelope.title);

  // Add suffix based on document status
  const suffix = isRejected ? '_rejected.pdf' : '_signed.pdf';

  const { data: newData } = await putPdfFileServerSide({
    name: `${name}${suffix}`,
    type: 'application/pdf',
    arrayBuffer: async () => Promise.resolve(pdfBuffer),
  });

  const postHog = PostHogServerClient();

  if (postHog) {
    postHog.capture({
      distinctId: nanoid(),
      event: 'App: Document Sealed',
      properties: {
        documentId: envelope.id,
        isRejected,
      },
    });
  }

  await prisma.$transaction(async (tx) => {
    await tx.envelope.update({
      where: {
        id: envelope.id,
      },
      data: {
        status: isRejected ? DocumentStatus.REJECTED : DocumentStatus.COMPLETED,
        completedAt: new Date(),
      },
    });

    await tx.documentData.update({
      where: {
        id: documentData.id,
      },
      data: {
        data: newData,
      },
    });

    await tx.documentAuditLog.create({
      data: createDocumentAuditLogData({
        type: DOCUMENT_AUDIT_LOG_TYPE.DOCUMENT_COMPLETED,
        envelopeId: envelope.id,
        requestMetadata,
        user: null,
        data: {
          transactionId: nanoid(),
          ...(isRejected ? { isRejected: true, rejectionReason } : {}),
        },
      }),
    });
  });

  if (sendEmail && !isResealing) {
    await sendCompletedEmail({ id, requestMetadata });
  }

  const updatedDocument = await prisma.envelope.findFirstOrThrow({
    where: {
      id: envelope.id,
    },
    include: {
      documentMeta: true,
      recipients: true,
    },
  });

  await triggerWebhook({
    event: isRejected
      ? WebhookTriggerEvents.DOCUMENT_REJECTED
      : WebhookTriggerEvents.DOCUMENT_COMPLETED,
    data: ZWebhookDocumentSchema.parse(mapEnvelopeToWebhookDocumentPayload(updatedDocument)),
    userId: envelope.userId,
    teamId: envelope.teamId ?? undefined,
  });
};