'use client';

import { useId, useState } from 'react';
import { FDI_LOWER_LEFT_TO_RIGHT, FDI_UPPER_LEFT_TO_RIGHT, getToothShapeKind } from '@/components/treatment/fdiToothMeta';
import { ToothGlyph } from '@/components/ui/treatment/ToothGlyph';
import { Dropdown } from '@/components/ui/common/Dropdown';
import { FDI_CHART_DESIGNS, type FdiChartDesignId } from '@/components/ui/treatment/fdiChartDesigns';
import type { FdiToothId } from '@/types/treatment';

const TOOTH_NUMBER_GAP = 'mt-1';

/** Six teeth each side of the midline (anteriors): slightly larger glyph + wrapper. */
const MIDLINE_SIX = new Set<FdiToothId>([
  '13', '12', '11', '21', '22', '23',
  '43', '42', '41', '31', '32', '33',
]);

function quadrantMirrored(fdi: FdiToothId): boolean {
  const q = fdi[0];
  return q === '2' || q === '3';
}

interface FdiToothChartProps {
  selected: ReadonlySet<FdiToothId>;
  onToggle: (fdi: FdiToothId) => void;
  disabled?: boolean;
}

export function FdiToothChart({ selected, onToggle, disabled }: FdiToothChartProps) {
  const uid = useId().replace(/:/g, '');
  const archPeak = 10;
  const [chartDesign, setChartDesign] = useState<FdiChartDesignId>('clinical');

  const TOOTH_TWEAKS: Record<FdiToothId, { glyph: string; offset: number; rotate: number }> = {
    '18': { glyph: 'w-[1.9rem] h-[4.5rem]', offset: 7, rotate: -11 },
    '17': { glyph: 'w-[2rem] h-[4.75rem]', offset: 8, rotate: -8 },
    '16': { glyph: 'w-[2.1rem] h-[4.95rem]', offset: 9, rotate: -6 },
    '15': { glyph: 'w-[1.8rem] h-[4.8rem]', offset: 9, rotate: -4 },
    '14': { glyph: 'w-[1.8rem] h-[4.85rem]', offset: 9, rotate: -2 },
    '13': { glyph: 'w-[1.9rem] h-[5.28rem]', offset: 8, rotate: -1 },
    '12': { glyph: 'w-[1.8rem] h-[5.02rem]', offset: 7, rotate: -1 },
    '11': { glyph: 'w-[1.8rem] h-[5.08rem]', offset: 7, rotate: -0.5 },
    '21': { glyph: 'w-[1.8rem] h-[5.08rem]', offset: 7, rotate: 0.5 },
    '22': { glyph: 'w-[1.8rem] h-[5.02rem]', offset: 7, rotate: 1 },
    '23': { glyph: 'w-[1.9rem] h-[5.28rem]', offset: 8, rotate: 1 },
    '24': { glyph: 'w-[1.8rem] h-[4.85rem]', offset: 9, rotate: 2 },
    '25': { glyph: 'w-[1.8rem] h-[4.8rem]', offset: 9, rotate: 4 },
    '26': { glyph: 'w-[2.1rem] h-[4.95rem]', offset: 9, rotate: 6 },
    '27': { glyph: 'w-[2rem] h-[4.75rem]', offset: 8, rotate: 8 },
    '28': { glyph: 'w-[1.9rem] h-[4.5rem]', offset: 7, rotate: 11 },

    '48': { glyph: 'w-[1.9rem] h-[4.55rem]', offset: -7, rotate: -11 },
    '47': { glyph: 'w-[2rem] h-[4.8rem]', offset: -8, rotate: -8 },
    '46': { glyph: 'w-[2.15rem] h-[5rem]', offset: -9, rotate: -6 },
    '45': { glyph: 'w-[1.82rem] h-[4.85rem]', offset: -9, rotate: -4 },
    '44': { glyph: 'w-[1.82rem] h-[4.9rem]', offset: -9, rotate: -2 },
    '43': { glyph: 'w-[1.88rem] h-[5.34rem]', offset: -8, rotate: -1 },
    '42': { glyph: 'w-[1.76rem] h-[5.04rem]', offset: -7, rotate: -1 },
    '41': { glyph: 'w-[1.74rem] h-[4.98rem]', offset: -7, rotate: -0.5 },
    '31': { glyph: 'w-[1.74rem] h-[4.98rem]', offset: -7, rotate: 0.5 },
    '32': { glyph: 'w-[1.76rem] h-[5.04rem]', offset: -7, rotate: 1 },
    '33': { glyph: 'w-[1.88rem] h-[5.34rem]', offset: -8, rotate: 1 },
    '34': { glyph: 'w-[1.82rem] h-[4.9rem]', offset: -9, rotate: 2 },
    '35': { glyph: 'w-[1.82rem] h-[4.85rem]', offset: -9, rotate: 4 },
    '36': { glyph: 'w-[2.15rem] h-[5rem]', offset: -9, rotate: 6 },
    '37': { glyph: 'w-[2rem] h-[4.8rem]', offset: -8, rotate: 8 },
    '38': { glyph: 'w-[1.9rem] h-[4.55rem]', offset: -7, rotate: 11 },
  };

  const toothSizeClass = (fdi: FdiToothId) => {
    const kind = getToothShapeKind(fdi);
    const mid = MIDLINE_SIX.has(fdi);
    switch (kind) {
      case 'incisor':
        return mid
          ? { wrapper: 'w-[2.1rem]', glyph: 'w-[1.68rem] h-[4.78rem]' }
          : { wrapper: 'w-[2rem]', glyph: 'w-[1.6rem] h-[4.6rem]' };
      case 'canine':
        return mid
          ? { wrapper: 'w-[2.2rem]', glyph: 'w-[1.78rem] h-[5.05rem]' }
          : { wrapper: 'w-[2.1rem]', glyph: 'w-[1.7rem] h-[4.9rem]' };
      case 'premolar':
        return mid
          ? { wrapper: 'w-[2.34rem]', glyph: 'w-[1.93rem] h-[5.02rem]' }
          : { wrapper: 'w-[2.25rem]', glyph: 'w-[1.85rem] h-[4.85rem]' };
      case 'molar':
        return mid
          ? { wrapper: 'w-[2.52rem]', glyph: 'w-[2.12rem] h-[5.1rem]' }
          : { wrapper: 'w-[2.45rem]', glyph: 'w-[2.05rem] h-[4.95rem]' };
      default:
        return { wrapper: 'w-[2.25rem]', glyph: 'w-[1.85rem] h-[4.85rem]' };
    }
  };

  const archOffset = (index: number, count: number, upper?: boolean) => {
    const center = (count - 1) / 2;
    const dist = Math.abs(index - center) / center;
    const curve = (1 - Math.pow(dist, 1.45)) * archPeak;
    return upper ? curve : -curve;
  };

  const archRotate = (index: number, count: number) => {
    const center = (count - 1) / 2;
    const normalized = (index - center) / center;
    return normalized * 6;
  };

  const Row = ({ teeth, upper }: { teeth: FdiToothId[]; upper?: boolean }) => (
    <div className="flex flex-wrap justify-center gap-x-1 gap-y-1">
      {teeth.map((fdi, i) => {
        const kind = getToothShapeKind(fdi);
        const gid = `${uid}-g-${fdi}-${i}`;
        const isSel = selected.has(fdi);
        const size = toothSizeClass(fdi);
        const tweak = TOOTH_TWEAKS[fdi];
        const offsetY = tweak ? tweak.offset : archOffset(i, teeth.length, upper);
        const rotate = tweak ? tweak.rotate : archRotate(i, teeth.length);
        const alignItems = upper ? 'items-end' : 'items-start';
        return (
          <div key={fdi} className={`flex flex-col items-center ${size.wrapper}`}>
            <div className={`h-[5.9rem] flex ${alignItems} justify-center`}>
              <button
                type="button"
                disabled={disabled}
                onClick={() => onToggle(fdi)}
                style={{ transform: `translateY(${offsetY}px) rotate(${rotate}deg)` }}
                className={`
                  rounded-[var(--radius-sm)] p-0.5 transition-transform
                  focus:outline-none focus-visible:ring-2 focus-visible:ring-primary/50
                  ${disabled ? 'opacity-50 cursor-not-allowed' : 'hover:scale-105 active:scale-95'}
                `}
                aria-pressed={isSel}
                aria-label={`FDI tooth ${fdi}${isSel ? ', selected' : ''}`}
              >
                <ToothGlyph
                  variant={chartDesign}
                  fdi={fdi}
                  kind={kind}
                  gradientId={gid}
                  selected={isSel}
                  upper={upper}
                  mirrored={quadrantMirrored(fdi)}
                  upsideDown={upper}
                  className={tweak?.glyph ?? size.glyph}
                />
              </button>
            </div>
          </div>
        );
      })}
    </div>
  );

  return (
    <div className="surface-card p-4 space-y-6">
      <div className="flex flex-col gap-3 sm:flex-row sm:items-start sm:justify-between">
        <div>
          <h3 className="text-sm font-semibold text-text-primary">FDI tooth chart</h3>
          <p className="text-xs text-text-muted mt-0.5">
            Tap teeth to multi-select (FDI). Selection applies to the active treatment record until you save.
          </p>
        </div>
        <div className="flex flex-col gap-2 sm:items-end w-full sm:max-w-xs">
          <Dropdown
            label="Chart style (temporary)"
            value={chartDesign}
            onChange={(e) => setChartDesign(e.target.value as FdiChartDesignId)}
          >
            {FDI_CHART_DESIGNS.map((d) => (
              <option key={d.id} value={d.id}>
                {d.label}
              </option>
            ))}
          </Dropdown>
          <p className="text-xs text-text-secondary tabular-nums text-right">
            Selected: {selected.size === 0 ? '—' : [...selected].sort().join(', ')}
          </p>
        </div>
      </div>

      <p className="text-[11px] uppercase tracking-wide text-text-muted mb-1 text-center">Upper arch</p>

      <div className="relative isolate py-1">
        <div
          className="pointer-events-none absolute left-1/2 top-3 bottom-3 w-px -translate-x-1/2 bg-border/70"
          aria-hidden
        />
        <div className="relative z-10 space-y-0">
          <Row teeth={FDI_UPPER_LEFT_TO_RIGHT} upper />
          <div className={`flex justify-center gap-x-1 ${TOOTH_NUMBER_GAP}`}>
            {FDI_UPPER_LEFT_TO_RIGHT.map((fdi) => {
              const size = toothSizeClass(fdi);
              const isSel = selected.has(fdi);
              return (
                <span
                  key={`u-${fdi}`}
                  className={`text-[10px] tabular-nums text-center leading-none ${size.wrapper} ${
                    isSel ? 'text-primary' : 'text-text-muted'
                  }`}
                >
                  {fdi}
                </span>
              );
            })}
          </div>

          <div
            className="my-4 h-px w-full max-w-[min(100%,42rem)] mx-auto bg-border/70"
            role="separator"
            aria-hidden
          />

          <div className="my-4 pt-1">
            <div className="flex justify-center gap-x-1">
              {FDI_LOWER_LEFT_TO_RIGHT.map((fdi) => {
                const size = toothSizeClass(fdi);
                const isSel = selected.has(fdi);
                return (
                  <span
                    key={`l-${fdi}`}
                    className={`text-[10px] tabular-nums text-center leading-none ${size.wrapper} ${
                      isSel ? 'text-primary' : 'text-text-muted'
                    }`}
                  >
                    {fdi}
                  </span>
                );
              })}
            </div>
            <div className={TOOTH_NUMBER_GAP}>
              <Row teeth={FDI_LOWER_LEFT_TO_RIGHT} />
            </div>
          </div>
        </div>
      </div>

      <p className="text-[11px] uppercase tracking-wide text-text-muted mt-1 text-center">Lower arch</p>
    </div>
  );
}