Bar chart for React

'use client';

import { round } from '@/lib/kit';
import { CartesianFrame, barPath, numberFormatter, rampColor, seriesColor, seriesOpacity, textWidth, useIntlLocale, type ChartA11y, type ChartSeries, type Datum } from '@/components/ui/chart';

export interface BarChartProps extends ChartA11y {
  /** Rows, one per category, e.g. { month: '2026-03', online: 21400, store: 9800 } */
  data: Datum[];
  /** Key of the category. "2026-03" and "2026-03-14" are read as dates and formatted per language. */
  xKey: string;
  /** One bar per series and category, in slot order (accent, grey, two accent tones) */
  series: ChartSeries[];
  /** Value format, e.g. { style: 'currency', currency: 'EUR', maximumFractionDigits: 0 } */
  format?: Intl.NumberFormatOptions;
  xFormat?: Intl.DateTimeFormatOptions;
  tooltipXFormat?: Intl.DateTimeFormatOptions;
  /** Several series side by side (default) or stacked to a total */
  stacked?: boolean;
  /** vertical columns (default) or horizontal bars with the labels on the left */
  orientation?: 'vertical' | 'horizontal';
  /** Value at the bar end. Single series and stacked totals, only where it fits. */
  valueLabels?: boolean;
  /** Single series: the category (x value) that keeps the accent, the others step back */
  highlight?: string;
  /** Vertical: plot height in px, axis labels included */
  height?: number;
  /** Horizontal: height of one row in px */
  rowHeight?: number;
  /** Legend above the plot. Default: for two series and more. */
  legend?: boolean;
  /** Header of the first table column */
  xLabel?: string;
  className?: string;
}

const GAP = 2;
const MAX = 24;

/**
 * Columns or bars: simple, grouped, stacked and horizontal.
 *   <BarChart data={rows} xKey="month" series={[{ key: 'online', label: 'Online' }, { key: 'store', label: 'Store' }]} stacked />
 */
export function BarChart({ data, xKey, series, format, xFormat, tooltipXFormat, stacked = false, orientation = 'vertical', valueLabels, highlight, height = 260, rowHeight = 40, legend, xLabel, label, summary, labels, animate, className }: BarChartProps) {
  const intl = useIntlLocale();
  const fmt = numberFormatter(intl, format);
  const horizontal = orientation === 'horizontal';
  const num = (d: Datum, k: string) => (typeof d[k] === 'number' ? (d[k] as number) : 0);
  const totals = data.map((d) => series.reduce((a, s) => a + Math.max(0, num(d, s.key)), 0));
  const all = data.flatMap((d) => series.map((s) => num(d, s.key)));
  const extent: [number, number] = stacked ? [0, Math.max(0, ...totals)] : [Math.min(0, ...all), Math.max(0, ...all)];
  const single = series.length === 1;
  const tipValue = (i: number) => (stacked ? totals[i] : single ? num(data[i], series[0].key) : null);
  const labelW = valueLabels ? Math.max(0, ...data.map((_, i) => { const v = tipValue(i); return v === null ? 0 : textWidth(fmt(v), 12); })) + 10 : 0;
  const plotHeight = horizontal ? data.length * rowHeight + 30 : height;
  const dim = (i: number, si: number) => (highlight !== undefined && single && String(data[i][xKey]) !== highlight ? rampColor(1) : seriesColor(si, series[si].color));

  return (
    <CartesianFrame
      data={data}
      xKey={xKey}
      series={series}
      format={format}
      xFormat={xFormat}
      tooltipXFormat={tooltipXFormat}
      height={plotHeight}
      scale="band"
      horizontal={horizontal}
      extent={extent}
      legend={legend}
      legendShape="rect"
      padRight={horizontal ? labelW : 0}
      padTop={!horizontal && valueLabels ? 12 : 0}
      total={stacked}
      xLabel={xLabel}
      label={label}
      summary={summary}
      labels={labels}
      animate={animate}
      className={className}
      marks={({ cat, band, val, animated, n, active, focus }) => {
        const zero = val(0);
        const thick = stacked || single ? Math.min(MAX, band * (horizontal ? 0.56 : 0.6)) : Math.min(MAX, (band * 0.72 - GAP * (series.length - 1)) / series.length);
        const groupW = stacked || single ? thick : thick * series.length + GAP * (series.length - 1);
        const delay = (i: number) => (animated ? ({ '--kitch-d': `${round((i / Math.max(1, n)) * 420, 0)}ms` } as React.CSSProperties) : undefined);
        return data.map((d, i) => {
          const c = cat(i);
          const start = round(c - groupW / 2);
          const faded = active !== null && active !== i;
          let marks: React.ReactNode;
          if (stacked) {
            let acc = 0;
            const visible = series.map((s, si) => ({ s, si, v: Math.max(0, num(d, s.key)) })).filter((x) => x.v > 0);
            marks = visible.map(({ s, si, v }, k) => {
              const a = val(acc);
              acc += v;
              const b = val(acc);
              const isTop = k === visible.length - 1;
              // The 2px surface gap sits on top of every segment but the last
              const len = Math.abs(b - a) - (isTop ? 0 : GAP);
              if (len <= 0) return null;
              const path = horizontal ? barPath(a, start, len, thick, isTop ? 4 : 0, 'right') : barPath(start, b + (isTop ? 0 : GAP), thick, len, isTop ? 4 : 0, 'up');
              return <path key={s.key} d={path} fill={seriesColor(si, s.color)} className="kitch-series" opacity={seriesOpacity(si, focus)} />;
            });
          } else {
            marks = series.map((s, si) => {
              const v = num(d, s.key);
              const p = val(v);
              const off = round(start + si * (thick + GAP));
              const len = Math.abs(p - zero);
              if (len < 0.5) return null;
              const path = horizontal ? barPath(Math.min(p, zero), off, len, thick, 4, v >= 0 ? 'right' : 'left') : barPath(off, Math.min(p, zero), thick, len, 4, v >= 0 ? 'up' : 'down');
              return <path key={s.key} d={path} fill={dim(i, si)} className="kitch-series" opacity={seriesOpacity(si, focus)} />;
            });
          }
          const tip = tipValue(i);
          const text = valueLabels && tip !== null ? fmt(tip) : null;
          const fits = text && (horizontal || textWidth(text, 11) <= band - 2);
          const highlighted = highlight !== undefined && String(d[xKey]) === highlight;
          return (
            <g key={i} className="transition-opacity duration-200 motion-reduce:transition-none" opacity={faded ? 0.55 : 1}>
              <g className={animated ? (horizontal ? 'kitch-grow-x' : tip !== null && tip < 0 ? 'kitch-grow-y-down' : 'kitch-grow-y') : undefined} style={delay(i)}>
                {marks}
              </g>
              {fits && (
                <text
                  x={horizontal ? val(tip!) + 8 : c}
                  y={horizontal ? c : val(Math.max(0, tip!)) - 7}
                  dy={horizontal ? '0.34em' : undefined}
                  textAnchor={horizontal ? 'start' : 'middle'}
                  className={`tabular-nums ${horizontal ? 'text-[12px]' : 'text-[11px]'} ${animated ? 'kitch-rise' : ''}`}
                  fontWeight={highlighted ? 600 : 500}
                  fill={highlighted || horizontal ? 'var(--foreground)' : 'var(--muted-foreground)'}
                  style={animated ? ({ '--kitch-d': `${round(380 + (i / Math.max(1, n)) * 420, 0)}ms` } as React.CSSProperties) : undefined}
                >
                  {text}
                </text>
              )}
            </g>
          );
        });
      }}
    />
  );
}