import { useEffect, useState } from 'react';
import { adminApi, type ManualRechargePreflight, type ManualRechargeResult } from '@/api/adminApi';
import { formatCents, isValidMoneyInput, yuanToMoneyUnits } from '@/utils/currency';
import { Button } from './Button';
import { Input } from './Input';
import { Modal } from './Modal';
import { Select } from './Select';
import { Textarea } from './Textarea';

export type ManualRechargeTarget = {
  id: string;
  name: string;
  code: string;
  balanceCents: number;
};

type ManualRechargeDialogProps = {
  initialTargetId?: string;
  lockTarget?: boolean;
  onClose: () => void;
  onCompleted: () => void | Promise<void>;
  open: boolean;
  targets: ManualRechargeTarget[];
};

export function ManualRechargeDialog({ initialTargetId, lockTarget = false, onClose, onCompleted, open, targets }: ManualRechargeDialogProps) {
  const [tenantId, setTenantId] = useState('');
  const [amount, setAmount] = useState('');
  const [remark, setRemark] = useState('');
  const [review, setReview] = useState<ManualRechargePreflight | null>(null);
  const [result, setResult] = useState<ManualRechargeResult | null>(null);
  const [idempotencyKey, setIdempotencyKey] = useState('');
  const [error, setError] = useState('');
  const [submitting, setSubmitting] = useState(false);

  useEffect(() => {
    if (!open) return;
    setTenantId(initialTargetId ?? targets[0]?.id ?? '');
    setAmount('');
    setRemark('');
    setReview(null);
    setResult(null);
    setIdempotencyKey('');
    setError('');
    setSubmitting(false);
  }, [initialTargetId, open]);

  if (!open) return null;
  const selectedTarget = targets.find((target) => target.id === tenantId);

  function resetReview() {
    setReview(null);
    setResult(null);
    setIdempotencyKey('');
    setError('');
  }

  function closeAndDestroyDraft() {
    if (submitting) return;
    setAmount('');
    setRemark('');
    resetReview();
    onClose();
  }

  async function preflight() {
    if (!tenantId || !Number.isFinite(Number(amount)) || !isValidMoneyInput(amount, { allowNegative: true, allowZero: false })) {
      setError('请填写非 0 的充值金额；金额支持负数冲正。');
      return;
    }
    setSubmitting(true);
    setError('');
    try {
      const preview = await adminApi.preflightManualRecharge({ tenantId, amountCents: yuanToMoneyUnits(amount) });
      setReview(preview);
      setIdempotencyKey(`manual-recharge:${crypto.randomUUID()}`);
    } catch (failure) {
      setError(failure instanceof Error ? failure.message : '人工充值资格核对失败');
    } finally {
      setSubmitting(false);
    }
  }

  async function submit() {
    if (!review || !idempotencyKey) return;
    setSubmitting(true);
    setError('');
    try {
      const nextResult = await adminApi.createManualRecharge({
        tenantId,
        amountCents: review.amountCents,
        expectedAccountUpdatedAt: review.expectedAccountUpdatedAt,
        idempotencyKey,
        remark,
      });
      setResult(nextResult);
      await onCompleted();
    } catch (failure) {
      setError(failure instanceof Error ? failure.message : '人工充值失败');
    } finally {
      setSubmitting(false);
    }
  }

  const footer = (requestClose: () => void) => result ? (
    <Button onClick={closeAndDestroyDraft}>完成</Button>
  ) : review ? (
    <>
      <Button disabled={submitting} onClick={resetReview} variant="ghost">返回修改</Button>
      <Button disabled={submitting} onClick={() => { void submit(); }}>{submitting ? '入账中...' : review.direction === 'topup' ? '确认充值' : '确认冲正'}</Button>
    </>
  ) : (
    <>
      <Button disabled={submitting} onClick={requestClose} variant="ghost">取消</Button>
      <Button disabled={submitting} onClick={() => { void preflight(); }}>{submitting ? '核对中...' : '下一步：核对信息'}</Button>
    </>
  );

  return (
    <Modal
      dirty={!result && !submitting && Boolean(amount.trim() || remark.trim() || review)}
      footer={({ requestClose }) => footer(requestClose)}
      onClose={closeAndDestroyDraft}
      open
      size="md"
      title={result ? '人工充值结果' : review ? '确认人工充值' : '企业人工充值'}
    >
      {result ? (
        <div className="manual-recharge-result" role="status">
          <strong>{result.amountCents > 0 ? '充值已入账' : '余额冲正已入账'}</strong>
          <span>订单号：{result.orderNo}</span>
          <span>充值后余额：¥{formatCents(result.balanceAfterCents)}</span>
          <span>操作单号：{result.operationId}{result.replayed ? '（幂等重放）' : ''}</span>
        </div>
      ) : review ? (
        <div className="manual-recharge-review">
          <p>请核对以下资金变更，确认后将立即写入企业账户。</p>
          <dl>
            <div><dt>充值对象</dt><dd><strong>{review.tenant.name}</strong><span>{review.tenant.code} · {review.tenant.id}</span></dd></div>
            <div><dt>操作方向</dt><dd>{review.direction === 'topup' ? '余额充值' : '余额冲正'}</dd></div>
            <div><dt>当前现金余额</dt><dd>¥{formatCents(review.balanceCents)}</dd></div>
            <div><dt>本次变动</dt><dd className={review.amountCents > 0 ? 'is-positive' : 'is-negative'}>{review.amountCents > 0 ? '+' : '-'}¥{formatCents(Math.abs(review.amountCents))}</dd></div>
            <div><dt>预计现金余额</dt><dd><strong>¥{formatCents(review.balanceAfterCents)}</strong></dd></div>
          </dl>
          {remark.trim() ? <p className="manual-recharge-review__remark"><strong>备注：</strong>{remark.trim()}</p> : null}
        </div>
      ) : (
        <div className="admin-system-modal-form">
          {lockTarget ? (
            <Input disabled label="企业名称" value={selectedTarget?.name ?? ''} />
          ) : (
            <Select label="企业名称" onChange={(event) => { setTenantId(event.target.value); resetReview(); }} options={targets.map((target) => ({ label: target.name, value: target.id }))} required value={tenantId} />
          )}
          <Input disabled label="当前现金余额" prefix="¥" value={formatCents(selectedTarget?.balanceCents ?? 0)} />
          <Input label="充值金额" onChange={(event) => { setAmount(event.target.value); resetReview(); }} prefix="¥" required step="0.0001" type="number" value={amount} />
          <Textarea className="admin-system-modal-form__wide" label="充值备注" onChange={(event) => { setRemark(event.target.value); resetReview(); }} rows={4} value={remark} />
        </div>
      )}
      {error ? <p className="form-error" role="alert">{error}</p> : null}
    </Modal>
  );
}