import React, { useRef, useState } from 'react';
import { checkLine } from '../api/client';
import { LineCheckResponse, TradeDirection } from '../api/types';
import { ErrorText, PrimaryButton, SecondaryButton, TextInput, Field, Select } from './controls';

export function CodeCheckDialog({
  open,
  onClose,
}: {
  open: boolean;
  onClose: () => void;
}) {
  const [code, setCode] = useState('');
  const [direction, setDirection] = useState<TradeDirection>(TradeDirection.IMPORT);
  const [originCountry, setOriginCountry] = useState('');
  const [destinationCountry, setDestinationCountry] = useState('');
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const [result, setResult] = useState<LineCheckResponse | null>(null);
  const dialogRef = useRef<HTMLDialogElement>(null);

  // Sync the dialog open/close with the prop
  React.useEffect(() => {
    const el = dialogRef.current;
    if (!el) return;
    if (open && !el.open) el.showModal();
    if (!open && el.open) el.close();
  }, [open]);

  const reset = () => {
    setCode('');
    setDirection(TradeDirection.IMPORT);
    setOriginCountry('');
    setDestinationCountry('');
    setError(null);
    setResult(null);
  };

  const handleClose = () => {
    reset();
    onClose();
  };

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    if (!code.trim()) return;

    setLoading(true);
    setError(null);
    setResult(null);

    try {
      const res = await checkLine({
        code: code.trim(),
        direction,
        originCountry: originCountry.trim() || null,
        destinationCountry: destinationCountry.trim() || null,
      });
      setResult(res);
    } catch (err: any) {
      setError(err?.message ?? 'Request failed');
    } finally {
      setLoading(false);
    }
  };

  if (!open) return null;

  return (
    <dialog
      ref={dialogRef}
      onClose={handleClose}
      className="w-full max-w-[520px] rounded-xl border border-line-header bg-white p-0 shadow-lg backdrop:bg-black/30"
    >
      <div className="flex items-center justify-between border-b border-line-header px-6 py-4">
        <h2 className="text-sm font-semibold">Quick code check</h2>
        <button
          type="button"
          onClick={handleClose}
          className="text-lg text-slate-400 hover:text-slate-600"
          aria-label="Close"
        >
          &times;
        </button>
      </div>

      <form onSubmit={handleSubmit} className="px-6 py-5">
        <Field label="Commodity code" htmlFor="cc-code">
          <TextInput
            id="cc-code"
            value={code}
            onChange={(e) => setCode(e.target.value)}
            placeholder="e.g. 6203 42 31"
            autoFocus
          />
        </Field>

        <Field label="Direction" htmlFor="cc-direction">
          <Select
            id="cc-direction"
            value={direction}
            onChange={(e) => setDirection(Number(e.target.value) as TradeDirection)}
          >
            <option value={TradeDirection.IMPORT}>Import</option>
            <option value={TradeDirection.EXPORT}>Export</option>
            <option value={TradeDirection.BOTH}>Both</option>
            <option value={TradeDirection.WAREHOUSE}>Warehouse</option>
          </Select>
        </Field>

        <div className="flex gap-4">
          <Field label="Origin country" htmlFor="cc-origin" className="flex-1">
            <TextInput
              id="cc-origin"
              value={originCountry}
              onChange={(e) => setOriginCountry(e.target.value)}
              placeholder="e.g. CN"
            />
          </Field>
          <Field label="Destination country" htmlFor="cc-dest" className="flex-1">
            <TextInput
              id="cc-dest"
              value={destinationCountry}
              onChange={(e) => setDestinationCountry(e.target.value)}
              placeholder="e.g. NL"
            />
          </Field>
        </div>

        <div className="flex gap-3">
          <PrimaryButton type="submit" disabled={loading || !code.trim()}>
            {loading ? 'Checking...' : 'Check'}
          </PrimaryButton>
          <SecondaryButton onClick={handleClose}>Close</SecondaryButton>
        </div>

        {error ? <ErrorText>{error}</ErrorText> : null}
      </form>

      {result ? <CodeCheckResult result={result} /> : null}
    </dialog>
  );
}

const STATUS_LABELS: Record<string, string> = {
  '1': 'OK',
  '2': 'Ambiguous',
  '3': 'Invalid',
  '4': 'Expiring',
};

const CONFIDENCE_LABELS: Record<string, string> = {
  '1': 'Red',
  '2': 'Amber',
  '3': 'Green',
};

const CONFIDENCE_COLORS: Record<string, string> = {
  '1': 'text-confidence-red',
  '2': 'text-confidence-amber',
  '3': 'text-green-600',
};

function CodeCheckResult({ result }: { result: LineCheckResponse }) {
  return (
    <div className="max-h-[45vh] overflow-y-auto border-t border-line-header px-6 py-5 text-xs">
      <div className="mb-3 grid grid-cols-[auto_1fr] gap-x-4 gap-y-2">
        <span className="text-slate-result">Input code</span>
        <span className="font-semibold">{result.inputCode}</span>

        <span className="text-slate-result">Resolved code</span>
        <span className="font-semibold">{result.formattedCode ?? result.resolvedCode ?? '-'}</span>

        <span className="text-slate-result">Description</span>
        <span>{result.codeDescription ?? '-'}</span>

        <span className="text-slate-result">Status</span>
        <span className="font-semibold">{STATUS_LABELS[String(result.status)] ?? result.status}</span>

        <span className="text-slate-result">Code confidence</span>
        <span className={`font-semibold ${CONFIDENCE_COLORS[String(result.codeConfidence)] ?? ''}`}>
          {CONFIDENCE_LABELS[String(result.codeConfidence)] ?? result.codeConfidence}
          {result.codeConfidenceReason ? ` — ${result.codeConfidenceReason}` : ''}
        </span>

        <span className="text-slate-result">Document confidence</span>
        <span className={`font-semibold ${CONFIDENCE_COLORS[String(result.documentConfidence)] ?? ''}`}>
          {CONFIDENCE_LABELS[String(result.documentConfidence)] ?? result.documentConfidence}
          {result.documentConfidenceReason ? ` — ${result.documentConfidenceReason}` : ''}
        </span>

        <span className="text-slate-result">Checked on</span>
        <span>{result.checkedOn}</span>
      </div>

      {result.warnings.length > 0 ? (
        <div className="mt-3">
          <span className="font-semibold">Warnings ({result.warnings.length})</span>
          <ul className="mt-1 list-inside list-disc space-y-1">
            {result.warnings.map((w, i) => (
              <li key={i} className={w.severity >= 2 ? 'text-confidence-amber' : ''}>
                {w.message}
              </li>
            ))}
          </ul>
        </div>
      ) : null}

      {result.documentsRequired.length > 0 ? (
        <div className="mt-3">
          <span className="font-semibold">Required documents ({result.documentsRequired.length})</span>
          <ul className="mt-1 list-inside list-disc space-y-1">
            {result.documentsRequired.map((d, i) => (
              <li key={i}>
                <span className="font-mono">{d.code}</span>
                {d.description ? ` — ${d.description}` : ''}
              </li>
            ))}
          </ul>
        </div>
      ) : null}
    </div>
  );
}