'use client';

import clsx from 'clsx';
import {
  XMarkIcon,
  ClockIcon,
  QrCodeIcon,
  MagnifyingGlassIcon,
  UserPlusIcon,
  ArrowPathIcon,
} from '@heroicons/react/24/outline';
import type { DoorPaymentMethod, DoorSummary } from '@/lib/api';
import { DOOR_PAYMENT_METHODS } from '@/lib/api';
import { formatCurrency } from '@/lib/utils';

export interface SessionEntry {
  idempotencyKey: string;
  ticketId: string;
  name: string;
  at: string;
  entry: 'scan' | 'search' | 'walkin';
  method: DoorPaymentMethod | null;
  amount: number;
  /** Epoch ms the action was fired; the undo window is measured from here. */
  startedAt: number;
  undone: boolean;
  failed: boolean;
}

const ENTRY_ICONS = {
  scan: QrCodeIcon,
  search: MagnifyingGlassIcon,
  walkin: UserPlusIcon,
};

const ENTRY_LABELS = {
  scan: 'Scanned',
  search: 'Search',
  walkin: 'Walk-in',
};

const METHOD_LABELS: Record<DoorPaymentMethod, string> = {
  cash: 'Cash',
  bitcoin: 'Bitcoin',
  transfer: 'Transfer',
  guest: 'Guest',
};

/** Totals for the current shift, computed from this session's own entries. */
function sessionTotals(entries: SessionEntry[]) {
  const totals: Record<DoorPaymentMethod, { count: number; total: number }> = {
    cash: { count: 0, total: 0 },
    bitcoin: { count: 0, total: 0 },
    transfer: { count: 0, total: 0 },
    guest: { count: 0, total: 0 },
  };
  let grand = 0;
  for (const entry of entries) {
    if (entry.undone || entry.failed || !entry.method) continue;
    totals[entry.method].count += 1;
    totals[entry.method].total += entry.amount;
    grand += entry.amount;
  }
  return { totals, grand };
}

function CashUpGrid({
  totals,
  currency,
}: {
  totals: Record<DoorPaymentMethod, { count: number; total: number }>;
  currency: string;
}) {
  return (
    <div className="grid grid-cols-2 gap-2">
      {DOOR_PAYMENT_METHODS.map((method) => (
        <div key={method} className="bg-gray-800 border border-gray-700 rounded-xl px-3 py-2.5">
          <p className="text-[11px] uppercase tracking-wide text-gray-500">{METHOD_LABELS[method]}</p>
          <p className="font-bold text-white text-base leading-tight">
            {method === 'guest' ? `${totals[method].count} free` : formatCurrency(totals[method].total, currency)}
          </p>
          {method !== 'guest' && (
            <p className="text-[11px] text-gray-500">
              {totals[method].count} {totals[method].count === 1 ? 'payment' : 'payments'}
            </p>
          )}
        </div>
      ))}
    </div>
  );
}

/**
 * The end-of-night view: what this shift took, what the whole event day took,
 * and the feed of who came in and how.
 */
export function SessionSheet({
  entries,
  summary,
  summaryLoading,
  showEventTotals,
  currency,
  onRefresh,
  onClose,
}: {
  entries: SessionEntry[];
  summary: DoorSummary | null;
  summaryLoading: boolean;
  /** Whole-event takings are admin/organizer only; door staff see their own shift. */
  showEventTotals: boolean;
  currency: string;
  onRefresh: () => void;
  onClose: () => void;
}) {
  const { totals, grand } = sessionTotals(entries);
  const liveEntries = entries.filter((e) => !e.undone);

  return (
    <div className="fixed inset-0 z-50 bg-gray-950 flex flex-col" style={{ height: '100dvh' }}>
      <header className="flex-shrink-0 bg-gray-900 border-b border-gray-800 px-4 py-3 safe-area-top flex items-center justify-between">
        <div>
          <p className="font-bold text-white text-lg">Session</p>
          <p className="text-xs text-gray-500">{liveEntries.length} checked in from this device</p>
        </div>
        <div className="flex items-center gap-2">
          {showEventTotals && (
            <button
              onClick={onRefresh}
              className="min-w-[48px] min-h-[48px] flex items-center justify-center rounded-full text-gray-400 active:text-white active:scale-95 transition-all"
              aria-label="Refresh totals"
            >
              <ArrowPathIcon className={clsx('w-5 h-5', summaryLoading && 'animate-spin')} />
            </button>
          )}
          <button
            onClick={onClose}
            className="min-w-[48px] min-h-[48px] flex items-center justify-center rounded-full text-gray-400 active:text-white active:scale-95 transition-all"
            aria-label="Close session view"
          >
            <XMarkIcon className="w-6 h-6" />
          </button>
        </div>
      </header>

      <div className="flex-1 min-h-0 overflow-y-auto px-4 py-4 space-y-5 pb-safe">
        {/* This shift */}
        <section className="space-y-2">
          <div className="flex items-baseline justify-between">
            <h2 className="text-sm font-bold text-white uppercase tracking-wide">This session</h2>
            <p className="text-primary-yellow font-bold">{formatCurrency(grand, currency)}</p>
          </div>
          <CashUpGrid totals={totals} currency={currency} />
        </section>

        {/* Whole event, from the server — the number to reconcile the cash box
            against. Admin/organizer only; the API enforces the same split. */}
        {showEventTotals && (
        <section className="space-y-2">
          <div className="flex items-baseline justify-between">
            <h2 className="text-sm font-bold text-white uppercase tracking-wide">Door total, whole event</h2>
            <p className="text-primary-yellow font-bold">
              {summary ? formatCurrency(summary.door.total, summary.currency) : '—'}
            </p>
          </div>
          {summary ? (
            <>
              <CashUpGrid totals={summary.door.byMethod} currency={summary.currency} />
              <div className="flex items-center justify-between bg-gray-800 border border-gray-700 rounded-xl px-3 py-2.5">
                <div>
                  <p className="text-[11px] uppercase tracking-wide text-gray-500">Pre-sale</p>
                  <p className="font-bold text-white">
                    {formatCurrency(summary.presale.total, summary.currency)}
                  </p>
                </div>
                <div className="text-right">
                  <p className="text-[11px] uppercase tracking-wide text-gray-500">Event total</p>
                  <p className="font-bold text-white">{formatCurrency(summary.total, summary.currency)}</p>
                </div>
              </div>
            </>
          ) : (
            <p className="text-sm text-gray-500">
              {summaryLoading ? 'Loading totals…' : 'Totals unavailable — pull to refresh.'}
            </p>
          )}
        </section>
        )}

        {/* Feed */}
        <section className="space-y-2">
          <h2 className="text-sm font-bold text-white uppercase tracking-wide">Recent check-ins</h2>
          {entries.length === 0 ? (
            <div className="text-center text-gray-500 py-10">
              <ClockIcon className="w-12 h-12 mx-auto mb-3 opacity-30" />
              <p className="text-sm">No check-ins yet</p>
            </div>
          ) : (
            <div className="space-y-2">
              {entries.map((entry) => {
                const Icon = ENTRY_ICONS[entry.entry];
                return (
                  <div
                    key={entry.idempotencyKey}
                    className={clsx(
                      'rounded-xl border px-3 py-2.5 flex items-center gap-3',
                      entry.failed
                        ? 'bg-red-950/40 border-red-900'
                        : entry.undone
                          ? 'bg-gray-900 border-gray-800 opacity-50'
                          : 'bg-gray-800 border-gray-700',
                    )}
                  >
                    <Icon className="w-5 h-5 text-gray-500 flex-shrink-0" />
                    <div className="flex-1 min-w-0">
                      <p
                        className={clsx(
                          'font-medium truncate',
                          entry.undone ? 'text-gray-500 line-through' : 'text-white',
                        )}
                      >
                        {entry.name}
                      </p>
                      <p className="text-xs text-gray-500 truncate">
                        {ENTRY_LABELS[entry.entry]}
                        {entry.method ? ` · ${METHOD_LABELS[entry.method]}` : ''}
                        {entry.method && entry.method !== 'guest'
                          ? ` ${formatCurrency(entry.amount, currency)}`
                          : ''}
                        {entry.failed ? ' · failed' : entry.undone ? ' · undone' : ''}
                      </p>
                    </div>
                    <p className="text-sm text-gray-400 flex-shrink-0">{entry.at}</p>
                  </div>
                );
              })}
            </div>
          )}
        </section>
      </div>
    </div>
  );
}