import React, { useState, useEffect } from 'react';
import { toast } from 'sonner';
import { api } from '@/api';
import { Button } from '@/components/ui/button';
import { Card, CardHeader, CardTitle, CardContent } from '@/components/ui/card';
import { Toggle } from './adminShared';

export default function BankSyncAdminCard() {
  const [config, setConfig]   = useState(null);
  const [loading, setLoading] = useState(true);
  const [saving, setSaving]   = useState(false);
  const [enabled, setEnabled] = useState(false);

  useEffect(() => {
    api.bankSyncConfig()
      .then(d => {
        setConfig(d);
        setEnabled(!!d.enabled);
      })
      .catch(() => {})
      .finally(() => setLoading(false));
  }, []);

  const handleSave = async () => {
    setSaving(true);
    try {
      const result = await api.setBankSyncConfig({ enabled });
      setConfig(result);
      setEnabled(!!result.enabled);
      toast.success(enabled ? 'Bank sync enabled.' : 'Bank sync disabled.');
    } catch (err) {
      toast.error(err.message || 'Failed to update bank sync setting.');
    } finally {
      setSaving(false);
    }
  };

  if (loading) {
    return (
      <Card>
        <CardContent className="py-8 text-center text-muted-foreground text-sm">
          Loading…
        </CardContent>
      </Card>
    );
  }

  const keySet = config?.encryption_key_set;
  const changed = enabled !== !!config?.enabled;

  return (
    <Card>
      <CardHeader className="pb-4">
        <CardTitle>Bank Sync (SimpleFIN)</CardTitle>
        <p className="text-sm text-muted-foreground mt-1">
          Allow users to connect their own SimpleFIN Bridge account to sync
          read-only bank transactions. Each user manages their own connection
          from the Data page — no bank credentials are stored.
        </p>
      </CardHeader>
      <CardContent className="space-y-5">

        {/* Encryption key status */}
        <div className={`rounded-lg border px-4 py-3 text-sm ${
          keySet
            ? 'border-emerald-500/25 bg-emerald-500/10 text-emerald-700 dark:text-emerald-400'
            : 'border-amber-500/25 bg-amber-500/10 text-amber-700 dark:text-amber-400'
        }`}>
          {keySet
            ? 'TOKEN_ENCRYPTION_KEY is configured. Bank sync can be enabled.'
            : 'TOKEN_ENCRYPTION_KEY is not set. Add a 32+ character key to your environment before enabling bank sync.'}
        </div>

        {/* Enable toggle */}
        <div className="flex items-center justify-between">
          <div>
            <p className="text-sm font-medium">Allow users to connect SimpleFIN</p>
            <p className="text-xs text-muted-foreground mt-0.5">
              When enabled, users see a Bank Sync section on their Data page.
            </p>
          </div>
          <Toggle
            checked={enabled}
            onChange={v => setEnabled(v)}
            disabled={!keySet}
            label="Enable bank sync"
          />
        </div>

        <div className="flex justify-end pt-2">
          <Button onClick={handleSave} disabled={saving || !changed || (!enabled ? false : !keySet)}>
            {saving ? 'Saving…' : 'Save'}
          </Button>
        </div>

      </CardContent>
    </Card>
  );
}