const { sanitizeText, parseList } = require('./commonValidation');

const SINGLE_ASSIGNMENT_POSITION_RULES = [
  {
    key: 'head-of-department',
    label: 'Head of the Department',
    pattern: /^head of (the )?department$/i,
  },
  {
    key: 'secretary',
    label: 'Secretary',
    pattern: /^secretary$/i,
  },
  {
    key: 'head-of-laboratory',
    label: 'Head of the Laboratory',
    pattern: /^head of (the )?laboratory$/i,
  },
];

const normalizeFacultyPosition = (value = '') =>
  sanitizeText(value)
    .toLowerCase()
    .replace(/\s+/g, ' ');

const getSingleAssignmentPositionRule = (position = '') => {
  const normalized = normalizeFacultyPosition(position);
  if (!normalized) return null;
  return SINGLE_ASSIGNMENT_POSITION_RULES.find((rule) => rule.pattern.test(normalized)) || null;
};

const getSingleAssignmentPositionKey = (position = '') =>
  getSingleAssignmentPositionRule(position)?.key || '';

const getSingleAssignmentPositionLabel = (position = '') =>
  getSingleAssignmentPositionRule(position)?.label || '';

const getSingleAssignmentPositionRegex = (position = '') =>
  getSingleAssignmentPositionRule(position)?.pattern || null;

const normalizeFacultyCreateInput = (body = {}) => ({
  name: sanitizeText(body.name),
  position: sanitizeText(body.position),
  specializations: parseList(body.specializations, /\r?\n/),
  email: parseList(body.email, /[,\n]/),
  scholarProfile: sanitizeText(body.scholarProfile),
});

const normalizeFacultyUpdateInput = (body = {}) => {
  const payload = {};

  if (typeof body.name === 'string') payload.name = body.name.trim();
  if (typeof body.position === 'string') payload.position = body.position.trim();
  if (body.specializations !== undefined) payload.specializations = parseList(body.specializations, /\r?\n/);
  if (body.email !== undefined) payload.email = parseList(body.email, /[,\n]/);
  if (typeof body.scholarProfile === 'string') payload.scholarProfile = body.scholarProfile.trim();

  return payload;
};

module.exports = {
  normalizeFacultyCreateInput,
  normalizeFacultyUpdateInput,
  getSingleAssignmentPositionKey,
  getSingleAssignmentPositionLabel,
  getSingleAssignmentPositionRegex,
};