import { createHash } from 'node:crypto';
import { existsSync } from 'node:fs';
import { resolve } from 'node:path';
import PDFDocument = require('pdfkit');

export interface ActPdfImage {
  id: string;
  findingId?: string;
  assetId?: string;
  signerName?: string;
  title?: string;
  capturedAt?: string | Date | null;
  sha256: string;
  buffer: Buffer;
}

export interface ActPdfContext {
  companyName?: string | null;
  departmentName?: string | null;
  areaName?: string | null;
  scopeName?: string | null;
  scopeCode?: string | null;
  scopeTypeName?: string | null;
  scopeTypeCode?: string | null;
  yacimientoName?: string | null;
  yacimientoCode?: string | null;
  leadInspectorName?: string | null;
}

function asRecord(value: unknown): Record<string, unknown> {
  return value && typeof value === 'object' && !Array.isArray(value) ? value as Record<string, unknown> : {};
}
function asArray(value: unknown): Array<Record<string, unknown>> {
  return Array.isArray(value) ? value.map(asRecord) : [];
}
function text(value: unknown, fallback = ''): string {
  return String(value ?? '').trim() || fallback;
}
function date(value: unknown): string {
  const parsed = new Date(String(value ?? ''));
  return Number.isFinite(parsed.getTime())
    ? new Intl.DateTimeFormat('es-AR', {
        timeZone: 'America/Argentina/Mendoza', day: '2-digit', month: '2-digit', year: 'numeric',
        hour: '2-digit', minute: '2-digit', hour12: false,
      }).format(parsed)
    : '-';
}
function fullName(value: Record<string, unknown>): string {
  return `${text(value.firstName)} ${text(value.lastName)}`.trim() || text(value.username);
}
function isPlaceholder(value: unknown): boolean {
  return text(value).startsWith('Acta de inspección en curso. Los Hallazgos');
}
function urgency(value: unknown): string {
  return text(value) === 'URGENT' ? 'Urgente' : text(value) === 'NON_URGENT' ? 'No urgente' : '-';
}
function dayType(value: unknown): string {
  return text(value) === 'BUSINESS' ? 'días hábiles' : text(value) === 'CALENDAR' ? 'días corridos' : '';
}
function deadlineBasis(value: unknown): string {
  return text(value) === 'ACT_DATE' ? 'Desde la fecha del Acta' : text(value) === 'GEDO_DATE' ? 'Desde la notificación formal' : '';
}
function manifestation(value: unknown): string {
  return text(value) === 'CONFORMITY' ? 'Firma sin disconformidad' : text(value) === 'DISSENT' ? 'Firma en disconformidad' : '';
}
function signatureStatus(value: unknown): string {
  return text(value) === 'SIGNED' ? 'Firmó' : text(value) === 'REFUSED' ? 'Se negó a firmar' : text(value) === 'ABSENT' ? 'Ausente' : 'No firmó';
}

// %PDF-1.4 is the document-version contract for consolidated Actas.
export async function buildInspectionActPdf(
  snapshot: Record<string, unknown>,
  images: ActPdfImage[] = [],
  fallbackContext: ActPdfContext = {},
): Promise<{ buffer: Buffer; sha256: string }> {
  const sealed = asRecord(snapshot);
  const locked = asRecord(sealed.lockedSnapshot ?? sealed.preparedSnapshot);
  const act = asRecord(locked.act);
  const inspection = asRecord(act.inspection ?? act.visit);
  const context = asRecord(locked.context);
  const company = asRecord(context.company);
  const department = asRecord(context.department);
  const area = asRecord(context.area);
  const scope = asRecord(context.scope);
  const leadInspector = asRecord(context.leadInspector);
  const inspectors = asArray(context.inspectors);
  const responsible = asRecord(locked.responsible);
  const inventories = asArray(locked.inventories);
  const findings = asArray(locked.findings);
  const signatures = asArray(sealed.signatures);
  const seal = asRecord(sealed.seal);
  const hash = text(sealed.finalSha256 ?? sealed.lockedSha256);
  const logo = resolve(process.cwd(), 'assets/logo-mendoza.png');

  const doc = new PDFDocument({ size: 'A4', pdfVersion: '1.4', margins: { top: 146, bottom: 80, left: 54, right: 54 }, compress: true });
  doc.registerFont('body', resolve(process.cwd(), 'assets/fonts/DejaVuSans.ttf'));
  doc.registerFont('body-bold', resolve(process.cwd(), 'assets/fonts/DejaVuSans-Bold.ttf'));
  const chunks: Buffer[] = [];
  doc.on('data', (part: Buffer) => chunks.push(part));
  const done = new Promise<Buffer>((complete, reject) => { doc.on('end', () => complete(Buffer.concat(chunks))); doc.on('error', reject); });
  const blue = '#162D69';
  const ink = '#202939';
  const muted = '#5A667C';

  const header = () => {
    doc.font('body-bold').fillColor(blue).fontSize(11).text('MINISTERIO DE ENERGÍA Y AMBIENTE', 54, 42);
    doc.text('DIRECCIÓN DE HIDROCARBUROS', 54, 58);
    if (existsSync(logo)) doc.image(logo, 474, 32, { fit: [62, 82] });
    doc.moveTo(54, 121).lineTo(540, 121).strokeColor('#BAC5DA').stroke();
    doc.y = 146;
  };
  doc.on('pageAdded', header);
  header();

  const need = (height: number) => { if (doc.y + height > doc.page.height - 85) doc.addPage(); };
  const section = (label: string) => {
    need(46);
    doc.moveDown(0.9);
    doc.font('body-bold').fillColor(blue).fontSize(12).text(label.toUpperCase());
    doc.moveTo(54, doc.y + 3).lineTo(540, doc.y + 3).strokeColor('#D5DCE8').stroke();
    doc.moveDown(0.55);
  };
  const body = (value: unknown) => {
    need(24);
    doc.font('body').fillColor(ink).fontSize(10.2).text(text(value, '-'), { lineGap: 3 });
    doc.moveDown(0.4);
  };
  const label = (name: string, value: unknown, allowEmpty = false) => {
    const rendered = text(value);
    if (!rendered && !allowEmpty) return;
    need(24);
    doc.font('body-bold').fillColor(ink).fontSize(9.8).text(`${name}: `, { continued: true });
    doc.font('body').text(rendered || '-');
    doc.moveDown(0.28);
  };
  const subheading = (value: string) => {
    need(32);
    doc.font('body-bold').fillColor(blue).fontSize(10.8).text(value);
    doc.moveDown(0.25);
  };
  const image = (entry: ActPdfImage, caption: string) => {
    need(235);
    const y = doc.y;
    doc.image(entry.buffer, 58, y, { fit: [470, 190] });
    doc.y = y + 195;
    doc.font('body').fontSize(8).fillColor(muted).text(`${caption} · SHA-256 ${entry.sha256}`, 58, doc.y, { width: 475 });
    doc.moveDown(0.5);
  };

  doc.font('body-bold').fillColor(ink).fontSize(18.5).text(`ACTA DE INSPECCIÓN ${text(act.code)}`);
  doc.moveDown(0.15);
  doc.font('body').fillColor(muted).fontSize(9).text('Documento consolidado de actuación inspectiva');

  section('1. Identificación del Acta');
  label('Código del Acta', act.code);
  if (act.actNumber || act.actYear) label('Número / Año', `${text(act.actNumber, '-')} / ${text(act.actYear, '-')}`);
  label('Inspección', inspection.code);
  label('Fecha y hora de actuación', date(act.occurredAt));
  label('Estado documental', 'Sellada');
  label('Versión de esquema', locked.schemaVersion ?? sealed.schemaVersion);

  section('2. Contexto territorial y operativo');
  label('Empresa / Operadora', company.name ?? fallbackContext.companyName);
  label('Departamento', department.name ?? fallbackContext.departmentName);
  label('Área', area.name ?? fallbackContext.areaName);
  const pathYacimientos = inventories.flatMap((inventory) => asArray(inventory.path))
    .filter((node) => text(node.typeCode).toLowerCase() === 'yacimiento');
  const scopeTypeCode = text(scope.typeCode ?? fallbackContext.scopeTypeCode).toLowerCase();
  const yacimientoNames = Array.from(new Set([
    ...(scopeTypeCode === 'yacimiento' ? [text(scope.name ?? fallbackContext.scopeName)] : []),
    ...pathYacimientos.map((node) => text(node.name)),
    text(fallbackContext.yacimientoName),
  ].filter(Boolean)));
  const yacimientoCodes = Array.from(new Set([
    ...(scopeTypeCode === 'yacimiento' ? [text(scope.code ?? fallbackContext.scopeCode)] : []),
    ...pathYacimientos.map((node) => text(node.code)),
    text(fallbackContext.yacimientoCode),
  ].filter(Boolean)));
  if (yacimientoNames.length) label(yacimientoNames.length > 1 ? 'Yacimientos' : 'Yacimiento', yacimientoNames.join(', '));
  if (yacimientoCodes.length) label(yacimientoCodes.length > 1 ? 'Códigos de yacimiento' : 'Código de yacimiento', yacimientoCodes.join(', '));
  if (scopeTypeCode && scopeTypeCode !== 'yacimiento') {
    const scopeLabel = `${text(scope.typeName ?? fallbackContext.scopeTypeName)} - ${text(scope.name ?? fallbackContext.scopeName)}${text(scope.code ?? fallbackContext.scopeCode) ? ` [${text(scope.code ?? fallbackContext.scopeCode)}]` : ''}`;
    label('Alcance de la inspección', scopeLabel);
  }
  label('Inicio efectivo de la inspección', date(inspection.actualStartedAt));

  section('3. Intervinientes');
  const leadName = fullName(leadInspector) || fallbackContext.leadInspectorName || '';
  label('Inspector/a responsable', leadName);
  const otherInspectors = inspectors.map(fullName).filter((name) => name && name !== leadName);
  if (otherInspectors.length) label('Otros inspectores actuantes', otherInspectors.join(', '));
  label('Situación del representante', text(responsible.attendanceStatus) === 'ABSENT' ? 'Ausente' : 'Presente');
  label('Representante de la empresa', responsible.fullName);
  const document = [text(responsible.documentType), text(responsible.documentNumber)].filter(Boolean).join(' ');
  label('Documento', document);
  label('Cargo o función', responsible.position);
  label('Correo electrónico', responsible.email);
  label('Teléfono', responsible.phone);
  if (text(responsible.attendanceStatus) === 'ABSENT') label('Motivo de ausencia', responsible.absenceReason);

  section('4. Datos del Acta');
  label('Objeto / Denominación', act.title);
  label('Urgencia', urgency(act.urgency));
  if (act.deadlineDays != null) {
    const duration = `${text(act.deadlineDays)} ${dayType(act.deadlineDayType)}`.trim();
    label('Plazo', duration);
    label('Cómputo del plazo', deadlineBasis(act.deadlineBasis));
    if (act.deadlineBaseAt) label('Fecha base', date(act.deadlineBaseAt));
    if (act.deadlineAt) label('Vencimiento', date(act.deadlineAt));
  }
  subheading('Descripción de lo actuado');
  if (text(act.summary) && !isPlaceholder(act.summary)) body(act.summary);
  else body(`Se realizó la inspección ${text(inspection.code)}. El contenido constatado se detalla en los hallazgos registrados a continuación.`);
  if (text(act.observations)) {
    subheading('Observaciones generales');
    body(act.observations);
  }

  section('5. Hallazgos');
  if (!findings.length) body('No se registraron hallazgos en esta Acta.');
  for (const finding of findings) {
    const inventory = inventories.find((item) => text(item.id) === text(finding.assetId)) ?? {};
    const catalog = asRecord(finding.catalog);
    const recurrence = asRecord(finding.recurrence);
    const path = asArray(inventory.path);
    const route = path.map((node) => `${text(node.typeName)}: ${text(node.name)}${text(node.code) ? ` [${text(node.code)}]` : ''}`).filter(Boolean).join(' > ');
    const number = text(finding.findingNumber, '?');
    need(100);
    doc.font('body-bold').fillColor(blue).fontSize(12).text(`HALLAZGO N° ${number} · ${text(finding.code)}`);
    doc.moveDown(0.2);
    label('Elemento afectado', `${text(inventory.typeName)} - ${text(inventory.name)}${text(inventory.code) ? ` [${text(inventory.code)}]` : ''}`);
    if (text(inventory.installationTypeName)) label('Tipo de instalación', inventory.installationTypeName);
    if (route) label('Ubicación / Ruta jerárquica', route);
    label('Denominación del hallazgo', finding.title);
    subheading('Qué se constató');
    body(finding.description);
    if (text(catalog.id)) {
      const source = [text(catalog.categoryName), text(catalog.title), text(catalog.code), catalog.sourceNumber ? `Ítem ${text(catalog.sourceNumber)}` : ''].filter(Boolean).join(' · ');
      label('Referencia de catálogo', source);
    } else {
      label('Referencia de catálogo', 'OTROS / hallazgo cargado en campo');
    }
    if (text(finding.glossary)) label('Criterio / Referencia técnica', finding.glossary);
    if (text(finding.legalBasis)) label('Normativa / Base legal', finding.legalBasis);
    if (finding.severity != null) label('Gravedad', `${text(finding.severity)}/10`);
    if (finding.isRecurrence) {
      label('Reincidencia', 'Sí');
      if (text(recurrence.code) || text(recurrence.title)) label('Antecedente relacionado', `${text(recurrence.code)}${text(recurrence.title) ? ` - ${text(recurrence.title)}` : ''}`);
    } else {
      label('Reincidencia', 'No');
    }
    const photos = images.filter((item) => item.findingId === text(finding.id));
    if (photos.length) {
      subheading(`Evidencia fotográfica (${photos.length})`);
      for (const photo of photos) image(photo, `Fotografía del hallazgo ${text(finding.code)}${photo.capturedAt ? ` · ${date(photo.capturedAt)}` : ''}`);
    } else {
      label('Evidencia fotográfica', 'Sin fotografías asociadas');
    }
    doc.moveDown(0.7);
  }

  section('6. Firmas y manifestaciones');
  for (const signature of signatures) {
    const name = text(signature.signerName);
    const inspector = text(signature.signerType) === 'INSPECTOR';
    const role = inspector ? 'Inspector/a' : 'Representante de la empresa';
    subheading(`${role}: ${name}`);
    const signedDocument = [text(signature.documentType), text(signature.documentNumber)].filter(Boolean).join(' ');
    if (signedDocument) label('Documento', signedDocument);
    label('Cargo o función', signature.position);
    label('Resultado', signatureStatus(signature.status));
    if (!inspector && text(signature.companyManifestation)) label('Manifestación', manifestation(signature.companyManifestation));
    if (signature.companyManifestation === 'DISSENT') label('Fundamento de la disconformidad', signature.companyStatement);
    if (text(signature.status) === 'REFUSED' || text(signature.status) === 'ABSENT') label('Motivo', signature.reason);
    label('Fecha y hora de la constancia', date(signature.signedAt ?? signature.createdAt));
    if (text(signature.source)) label('Origen de la constancia', text(signature.source) === 'ANDROID' ? 'Aplicación móvil' : 'Dashboard web');
    const signatureImage = images.find((item) => item.signerName === name && item.sha256 === text(signature.imageSha256));
    if (signatureImage) {
      need(100);
      const y = doc.y;
      doc.image(signatureImage.buffer, 60, y, { fit: [230, 60] });
      doc.y = y + 66;
    }
    doc.moveDown(0.5);
  }

  section('7. Integridad y cierre');
  label('Contenido bloqueado', date(locked.lockedAt));
  label('Sellado en servidor', date(seal.serverSealedAt));
  label('Fecha informada por dispositivo', date(seal.deviceSealedAt));
  label('Modo de cierre', seal.uploadMode);
  body(`SHA-256 del cierre: ${hash}`);
  body(`SHA-256 del contenido bloqueado: ${text(sealed.lockedSha256)}`);
  need(28);
  doc.fontSize(8).fillColor(muted).text(`Acta ${text(act.code)} · plantilla consolidada v3 · ${date(seal.serverSealedAt)}`, 54, doc.y);

  doc.end();
  const buffer = await done;
  return { buffer, sha256: createHash('sha256').update(buffer).digest('hex') };
}