import Joi from 'joi';
import Boom from '@hapi/boom';
import { requirePermission, credentials, patientScopeFilter } from '../plugins/auth.js';
import { Patient } from '../models/Patient.js';
import { Session } from '../models/Session.js';
import { User } from '../models/User.js';
import { toPatientDto, toSessionDto } from '../utils/serialize.js';
import { isMobileNumber } from '../services/cryptoPii.js';
import { importWorkbook, payloadToBuffer } from '../services/importPatients.js';

const objectId = Joi.string().hex().length(24);

const patientPayload = Joi.object({
  sourcePatientId: Joi.string().trim(),
  name: Joi.string().trim().min(1).required(),
  mobile: Joi.string().allow('', null),
  age: Joi.number().allow(null),
  gender: Joi.string().allow('', null),
  lungCondition: Joi.string().allow('', null),
  otherHealthCondition: Joi.string().allow('', null),
  language: Joi.string().allow('', null),
  sessionLanguage: Joi.string().allow('', null),
  consentType: Joi.string().allow('', null),
  isNewOrOld: Joi.string().allow('', null),
  doctor: Joi.object({
    sourceId: Joi.string().allow('', null),
    name: Joi.string().allow('', null),
    uin: Joi.string().allow('', null),
  }),
  assignedEducator: objectId.allow(null, ''),
});

function applyPatientFields(patient, body, canAssign) {
  patient.name = body.name;
  if (body.mobile && !isMobileNumber(body.mobile)) throw Boom.badRequest('Mobile must be 10 digits.');
  patient.mobile = body.mobile ? String(body.mobile).trim() : '';
  patient.age = body.age ?? null;
  patient.gender = body.gender || '';
  patient.lungCondition = body.lungCondition || '';
  patient.otherHealthCondition = body.otherHealthCondition || '';
  patient.sessionLanguage = body.sessionLanguage || body.language || '';
  patient.consentType = body.consentType || '';
  patient.isNewOrOld = body.isNewOrOld || '';
  if (body.doctor) {
    patient.doctor = {
      sourceId: body.doctor.sourceId || '',
      name: body.doctor.name || '',
      uin: body.doctor.uin || '',
    };
  }
  if (canAssign && 'assignedEducator' in body) {
    patient.assignedEducator = body.assignedEducator || null;
  }
}

export function patientRoutes(server) {
  server.route({
    method: 'GET',
    path: '/api/patients',
    options: { pre: [{ method: requirePermission('patients', 'view') }] },
    handler: async (request) => {
      const {
        search = '',
        gender,
        lungCondition,
        educator,
        unassigned,
        page = 1,
        limit = 20,
      } = request.query;
      const filter = { ...patientScopeFilter(request) };
      if (search) {
        const rx = new RegExp(search.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'), 'i');
        filter.$or = [{ name: rx }, { mobile: rx }, { sourcePatientId: rx }];
      }
      if (gender) filter.gender = gender;
      if (lungCondition) filter.lungCondition = lungCondition;
      if (educator) filter.assignedEducator = educator;
      if (unassigned === 'true' || unassigned === true) filter.assignedEducator = null;
      const skip = (Number(page) - 1) * Number(limit);
      const [items, total] = await Promise.all([
        Patient.find(filter).populate('assignedEducator', 'firstName lastName email').sort({ lastVisitDate: -1, createdAt: -1 }).skip(skip).limit(Number(limit)),
        Patient.countDocuments(filter),
      ]);
      return { items: items.map(toPatientDto), total, page: Number(page), limit: Number(limit) };
    },
  });

  server.route({
    method: 'GET',
    path: '/api/patients/filters',
    options: { pre: [{ method: requirePermission('patients', 'view') }] },
    handler: async (request) => {
      const scope = patientScopeFilter(request);
      const [genders, conditions] = await Promise.all([
        Patient.distinct('gender', scope),
        Patient.distinct('lungCondition', scope),
      ]);
      return {
        genders: genders.filter(Boolean),
        lungConditions: conditions.filter(Boolean),
      };
    },
  });

  server.route({
    method: 'POST',
    path: '/api/patients/import',
    options: {
      pre: [{ method: requirePermission('patients', 'import') }],
      payload: {
        output: 'data',
        parse: true,
        multipart: true,
        maxBytes: 25 * 1024 * 1024,
        allow: 'multipart/form-data',
        timeout: false,
      },
    },
    handler: async (request) => {
      const file = request.payload?.file || request.payload?.upload;
      if (!file) throw Boom.badRequest('Upload an .xlsx file in the "file" field');
      const buffer = await payloadToBuffer(file);
      if (!buffer?.length) throw Boom.badRequest('Empty file');
      const result = await importWorkbook(buffer);
      if (!result.ok) throw Boom.badRequest(result.error);
      return result;
    },
  });

  server.route({
    method: 'GET',
    path: '/api/patients/{id}',
    options: {
      pre: [{ method: requirePermission('patients', 'view') }],
      validate: { params: Joi.object({ id: objectId.required() }) },
    },
    handler: async (request) => {
      const patient = await Patient.findOne({ _id: request.params.id, ...patientScopeFilter(request) })
        .populate('assignedEducator', 'firstName lastName email');
      if (!patient) throw Boom.notFound('Patient not found');
      const sessions = await Session.find({ patient: patient._id }).sort({ visitDate: -1, createdAt: -1 });
      return { ...toPatientDto(patient), sessions: sessions.map(toSessionDto) };
    },
  });

  server.route({
    method: 'POST',
    path: '/api/patients',
    options: {
      pre: [{ method: requirePermission('patients', 'add') }],
      validate: { payload: patientPayload },
    },
    handler: async (request) => {
      const creds = credentials(request);
      const body = request.payload;
      const sourcePatientId = body.sourcePatientId || `MANUAL-${Date.now()}`;
      if (await Patient.findOne({ sourcePatientId })) {
        throw Boom.conflict('Patient ID already exists');
      }
      const patient = new Patient({ sourcePatientId });
      const canAssign = creds.isSuperAdmin || (creds.modules?.patients || []).includes('edit');
      applyPatientFields(patient, body, canAssign && creds.scopes?.patients !== 'assigned');
      if (creds.scopes?.patients === 'assigned') {
        patient.assignedEducator = creds.user._id;
      }
      await patient.save();
      await patient.populate('assignedEducator', 'firstName lastName email');
      return toPatientDto(patient);
    },
  });

  server.route({
    method: 'PATCH',
    path: '/api/patients/{id}',
    options: {
      pre: [{ method: requirePermission('patients', 'edit') }],
      validate: {
        params: Joi.object({ id: objectId.required() }),
        payload: patientPayload,
      },
    },
    handler: async (request) => {
      const creds = credentials(request);
      const patient = await Patient.findOne({ _id: request.params.id, ...patientScopeFilter(request) });
      if (!patient) throw Boom.notFound('Patient not found');
      const canAssign = creds.isSuperAdmin || creds.scopes?.patients !== 'assigned';
      applyPatientFields(patient, request.payload, canAssign);
      if (request.payload.assignedEducator && canAssign) {
        const educator = await User.findById(request.payload.assignedEducator).populate('role');
        if (!educator) throw Boom.badRequest('Invalid PRT');
      }
      await patient.save();
      await patient.populate('assignedEducator', 'firstName lastName email');
      return toPatientDto(patient);
    },
  });

  server.route({
    method: 'DELETE',
    path: '/api/patients/{id}',
    options: {
      pre: [{ method: requirePermission('patients', 'delete') }],
      validate: { params: Joi.object({ id: objectId.required() }) },
    },
    handler: async (request) => {
      const patient = await Patient.findOne({ _id: request.params.id, ...patientScopeFilter(request) });
      if (!patient) throw Boom.notFound('Patient not found');
      await Session.deleteMany({ patient: patient._id });
      await patient.deleteOne();
      return { ok: true };
    },
  });
}