import React from 'react';
import type { Patient } from 'fhir/r4';
import { Video } from 'lucide-react';
import type { RowStatusTone } from '../../../components/ui/row-meta';
import type { ActionDescriptor, QueueItem } from './encounterLifecycle';
import { appointmentIsVirtual, encounterIsVirtual } from '../../../utils/encounterClass';

// Shared focus-panel display helpers - used by both EncounterFocusPanel (provider tier) and
// SupportFocusPanel (support tier). Kept here so the two panels can't drift out of sync.

/** Button-variant `btn` class mapping for a focus panel's action bar. */
export const BTN_CLASS: Record<ActionDescriptor['variant'], string> = {
  go: 'btn btn-green',
  primary: 'btn btn-blue',
  // Was hand-rolled Tailwind borders, which rendered as no border at all: `#...root .btn` sets
  // `border: 1px solid transparent` at (1,1,0) and a utility class scores (0,1,0), so the colour
  // silently lost and these actions drew as plain text. `.btn-blue-ghost` is ID-scoped like the
  // other variants, and blue-ghost is the standard for secondary acts since grey was retired.
  outline: 'btn btn-blue-ghost',
  amber: 'btn bg-amber-100 text-amber-800 border border-amber-300 hover:bg-amber-200',
};

/** "48 - M" - age in years + sex initial, from a Patient (empty string when unknown). */
export const ageSex = (patient?: Patient): string => {
  const sex = patient?.gender ? patient.gender[0].toUpperCase() : '';
  if (!patient?.birthDate) return sex;
  const age = Math.floor((Date.now() - new Date(patient.birthDate).getTime()) / (365.25 * 864e5));
  return [String(age), sex].filter(Boolean).join(' · ');
};

/**
 * WHICH KIND OF VISIT THIS IS, beside which stage it is at.
 *
 * A row that says only "In progress" does not tell a clinician whether the patient is in a room
 * down the corridor or waiting in a meeting window, and those are different next actions. Read from
 * the Encounter's own class rather than re-derived from the appointment's location, for the same
 * reason the video door is: the class is the settled answer and it is settled from two directions.
 *
 * Absent rather than "In person" when it is not virtual. Naming the ordinary case on every row buys
 * nothing and costs the exception its contrast, which is the whole job of this chip.
 */
export const ModalityBadge: React.FC<{ item: QueueItem; virtualLocationId?: string }> = ({ item, virtualLocationId }) => {
  if (!queueItemIsVirtual(item, virtualLocationId)) return null;
  return (
    <span className="inline-flex items-center gap-1.5 text-xs font-bold px-2.5 py-1 rounded-full bg-sky-100 text-sky-800 dark:bg-sky-900/40 dark:text-sky-300">
      <Video className="w-3.5 h-3.5" />Video visit
    </span>
  );
};

// A row with no Encounter yet is still a video visit when its booking names the virtual Location.
export const queueItemIsVirtual = (item: QueueItem, virtualLocationId?: string): boolean =>
  item.encounter ? encounterIsVirtual(item.encounter) : appointmentIsVirtual(item.appointment, virtualLocationId);

const QUEUE_STATUS: Record<QueueItem['status'], { label: string; tone: RowStatusTone }> = {
  'in-progress': { label: 'In progress', tone: 'attention' },
  onleave: { label: 'On leave', tone: 'plain' },
  triaged: { label: 'Roomed · ready', tone: 'done' },
  arrived: { label: 'Checked in', tone: 'done' },
  finished: { label: 'Finished', tone: 'plain' },
  scheduled: { label: 'Scheduled', tone: 'plain' },
};

/* The header pill's tone for each row tone - the same tones the working chart's header uses (b4030fa1d). */
const PILL_TONE: Record<RowStatusTone, string> = {
  attention: 'ak-pill--warn',
  done: 'ak-pill--ok',
  ended: '',
  danger: 'ak-pill--bad',
  plain: '',
};

/**
 * A visit's state in a focus panel header: the SHARED pill, as the deck draws it and as the working chart's
 * header already does (P06, Captain + Codex 2026-09-30). On leave reads as info there too. Queue rows keep
 * their coloured words (`RowStatus`); only the header changed.
 */
export const VisitStatus: React.FC<{ item: QueueItem }> = ({ item }) => {
  const { label, tone } = QUEUE_STATUS[item.status] ?? QUEUE_STATUS.scheduled;
  const toneClass = item.status === 'onleave' ? 'ak-pill--info' : PILL_TONE[tone];
  return <span className={toneClass ? `ak-pill ${toneClass}` : 'ak-pill'}>{label}</span>;
};