import React, { useMemo, useState } from 'react';
import { Avatar } from '../ui/controls';
import { Icon } from '../ui/Icon';
import { SplitBar } from '../ui/charts';
import { colorFor, formatEuro, formatHours } from '../../lib/format';
import type { GroupRow } from '../../lib/api';

type SortKey = 'name' | 'minutes' | 'billable_minutes' | 'amount' | 'utilization';

/**
 * Tabelle wie im Harvest-Report: Name, Stunden mit Doppelbalken, Auslastung,
 * abrechenbare Stunden mit Anteil, Betrag. Spaltenkoepfe sortieren.
 */
export const ReportTable: React.FC<{
  rows: GroupRow[];
  label: string;
  kind: 'clients' | 'projects' | 'tasks' | 'users' | 'team';
  showAmounts?: boolean;
  onRowClick?: (row: GroupRow) => void;
  totals?: boolean;
}> = ({ rows, label, kind, showAmounts = true, onRowClick, totals = true }) => {
  const [sort, setSort] = useState<{ key: SortKey; dir: 1 | -1 }>({ key: kind === 'users' ? 'name' : 'minutes', dir: kind === 'users' ? 1 : -1 });
  const sorted = useMemo(
    () =>
      [...rows].sort((a, b) => {
        const av = sort.key === 'name' ? a.name : (a[sort.key] ?? -1);
        const bv = sort.key === 'name' ? b.name : (b[sort.key] ?? -1);
        return (typeof av === 'string' ? av.localeCompare(bv as string, 'de') : (av as number) - (bv as number)) * sort.dir;
      }),
    [rows, sort]
  );
  const max = Math.max(1, ...rows.map((r) => r.minutes));
  const showUtil = kind === 'users';
  const sum = rows.reduce(
    (s, r) => ({ minutes: s.minutes + r.minutes, billable: s.billable + r.billable_minutes, amount: s.amount + r.amount }),
    { minutes: 0, billable: 0, amount: 0 }
  );

  const head = (key: SortKey, text: string, align: 'left' | 'right' = 'right', className = '') => (
    <th className={`px-3 py-3 ${align === 'right' ? 'text-right' : 'text-left'} ${className}`}>
      <button
        onClick={() => setSort({ key, dir: sort.key === key ? ((sort.dir * -1) as 1 | -1) : key === 'name' ? 1 : -1 })}
        className={`inline-flex items-center gap-1 font-extrabold uppercase tracking-wider hover:text-ink-700 ${sort.key === key ? 'text-ink-700' : ''}`}
      >
        {text}
        {sort.key === key && <Icon name={sort.dir === 1 ? 'chevronUp' : 'chevronDown'} className="h-3 w-3" strokeWidth={2.5} />}
      </button>
    </th>
  );

  if (rows.length === 0) return <p className="px-4 py-10 text-center text-sm text-ink-400">Keine Buchungen im Zeitraum.</p>;

  return (
    <div className="scrollbar-slim overflow-x-auto">
      <table className="w-full min-w-[900px] table-fixed text-sm">
        <thead>
          <tr className="border-b border-ink-200 text-[11px] text-ink-400">
            {head('name', label, 'left', 'pl-4')}
            {head('minutes', 'Stunden', 'right', 'w-[108px]')}
            <th className="w-[20%] px-3 py-3" />
            {showUtil && head('utilization', 'Auslastung', 'right', 'w-[116px]')}
            {head('billable_minutes', 'Billable Std.', 'right', 'w-[160px]')}
            {showAmounts && head('amount', 'Billable Betrag', 'right', 'w-[150px] pr-4')}
          </tr>
        </thead>
        <tbody>
          {sorted.map((r, i) => {
            const share = r.minutes ? Math.round((r.billable_minutes / r.minutes) * 100) : 0;
            const clickable = Boolean(onRowClick);
            return (
              <tr
                key={String(r.key)}
                onClick={() => onRowClick?.(r)}
                className={`animate-rise border-b border-ink-100 last:border-0 ${clickable ? 'cursor-pointer hover:bg-brand-50/50' : 'hover:bg-ink-50'}`}
                style={{ '--i': Math.min(i, 15) } as React.CSSProperties}
              >
                <td className="py-3 pl-4 pr-3">
                  <div className="flex min-w-0 items-center gap-2.5">
                    {kind === 'users' || kind === 'team' ? (
                      <Avatar id={r.user_id} name={r.name} color={r.color} avatar={r.avatar} size={28} external={r.is_external} />
                    ) : kind !== 'tasks' ? (
                      <span className="h-2.5 w-2.5 shrink-0 rounded-full" style={{ background: colorFor(r.customer_id ?? r.project_id ?? r.name, r.color) }} />
                    ) : null}
                    <span className="min-w-0">
                      <span className={`block break-words font-bold ${clickable ? 'text-ink-900 underline decoration-ink-200 underline-offset-4 group-hover:decoration-brand-400' : 'text-ink-800'}`}>{r.name}</span>
                      {r.customer_name && <span className="block break-words text-[11px] text-ink-400">{r.customer_name}{r.code ? ` · ${r.code}` : ''}</span>}
                    </span>
                  </div>
                </td>
                <td className="tabular whitespace-nowrap px-3 py-3 text-right font-extrabold text-ink-900">{formatHours(r.minutes)}</td>
                <td className="px-3 py-3">
                  <SplitBar a={r.billable_minutes} b={r.non_billable_minutes} max={max} delay={i * 30} />
                </td>
                {showUtil && (
                  <td className={`tabular px-3 py-3 text-right font-bold ${r.utilization == null ? 'text-ink-300' : r.utilization > 105 ? 'text-red-600' : r.utilization >= 75 ? 'text-brand-700' : 'text-ink-600'}`}>
                    {r.utilization == null ? '–' : `${r.utilization} %`}
                  </td>
                )}
                <td className="tabular whitespace-nowrap px-3 py-3 text-right text-ink-700">
                  {formatHours(r.billable_minutes)} <span className="inline-block w-14 whitespace-nowrap text-ink-400">({share} %)</span>
                </td>
                {showAmounts && <td className="tabular whitespace-nowrap py-3 pl-3 pr-4 text-right font-extrabold text-ink-900">{formatEuro(r.amount, 2)}</td>}
              </tr>
            );
          })}
        </tbody>
        {totals && (
          <tfoot>
            <tr className="border-t-2 border-ink-200 bg-ink-50/60 font-extrabold text-ink-900">
              <td className="py-3 pl-4 pr-3">Summe</td>
              <td className="tabular px-3 py-3 text-right">{formatHours(sum.minutes)}</td>
              <td />
              {showUtil && <td />}
              <td className="tabular px-3 py-3 text-right">
                {formatHours(sum.billable)} <span className="inline-block w-14 whitespace-nowrap font-normal text-ink-400">({sum.minutes ? Math.round((sum.billable / sum.minutes) * 100) : 0} %)</span>
              </td>
              {showAmounts && <td className="tabular py-3 pl-3 pr-4 text-right">{formatEuro(sum.amount, 2)}</td>}
            </tr>
          </tfoot>
        )}
      </table>
    </div>
  );
};