'use client';

import { useEffect, useState, useCallback } from 'react';
import { toast } from 'sonner';
import { PageHeader } from '@/components/navigation/page-header';
import { Card, CardContent } from '@/components/ui/card';
import { Badge } from '@/components/ui/badge';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Switch } from '@/components/ui/switch';
import { Skeleton } from '@/components/ui/skeleton';
import { Alert, AlertDescription, AlertTitle } from '@/components/ui/alert';
import {
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableHeader,
  TableRow,
} from '@/components/ui/table';
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from '@/components/ui/select';
import { Search, RefreshCw, Building2, EyeOff } from 'lucide-react';

interface Company {
  id: string;
  companyName: string;
  companyType: number | null;
  companyTypeLabel: string | null;
  inScope: boolean;
}

type ScopeFilter = 'all' | 'in' | 'out';

export default function ClientScopePage() {
  const [companies, setCompanies] = useState<Company[]>([]);
  const [total, setTotal] = useState(0);
  const [excluded, setExcluded] = useState(0);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);
  const [search, setSearch] = useState('');
  const [typeFilter, setTypeFilter] = useState<string>('all');
  const [scopeFilter, setScopeFilter] = useState<ScopeFilter>('all');
  const [toggling, setToggling] = useState<string | null>(null);

  const load = useCallback(async () => {
    setLoading(true);
    setError(null);
    try {
      const params = new URLSearchParams();
      if (search) params.set('search', search);
      if (typeFilter !== 'all') params.set('type', typeFilter);
      const res = await fetch(`/api/admin/company-scope?${params}`);
      if (!res.ok) {
        const d = await res.json().catch(() => ({})) as { error?: string };
        throw new Error(d.error ?? `Request failed: ${res.status}`);
      }
      const data = await res.json() as { companies: Company[]; total: number; excluded: number };
      setCompanies(data.companies);
      setTotal(data.total);
      setExcluded(data.excluded);
    } catch (err) {
      setError(err instanceof Error ? err.message : 'Failed to load');
    } finally {
      setLoading(false);
    }
  }, [search, typeFilter]);

  useEffect(() => {
    void load();
  }, [load]);

  async function toggle(company: Company, next: boolean) {
    setToggling(company.id);
    try {
      const res = await fetch(`/api/admin/company-scope/${company.id}`, {
        method: 'PATCH',
        headers: { 'content-type': 'application/json' },
        body: JSON.stringify({ inScope: next }),
      });
      if (!res.ok) {
        const d = await res.json().catch(() => ({})) as { error?: string };
        throw new Error(d.error ?? `Failed: ${res.status}`);
      }
      setCompanies((prev) =>
        prev.map((c) => (c.id === company.id ? { ...c, inScope: next } : c))
      );
      setExcluded((n) => (next ? Math.max(0, n - 1) : n + 1));
      toast.success(`${company.companyName} ${next ? 'included in' : 'excluded from'} scope`);
    } catch (err) {
      toast.error(err instanceof Error ? err.message : 'Toggle failed');
    } finally {
      setToggling(null);
    }
  }

  const visible = companies.filter((c) => {
    if (scopeFilter === 'in') return c.inScope;
    if (scopeFilter === 'out') return !c.inScope;
    return true;
  });

  const uniqueTypes = Array.from(new Set(companies.map((c) => c.companyType).filter(Boolean))).sort() as number[];

  return (
    <>
      <PageHeader
        title="Client scope"
        description="Mark which companies count as Wulf recurring-revenue clients. Excluded companies are hidden from dashboard KPIs and ticket analytics."
        breadcrumbs={[{ label: 'Admin', href: '/admin' }, { label: 'Client scope' }]}
        accent
        actions={
          <Button variant="outline" size="sm" onClick={() => void load()} disabled={loading}>
            <RefreshCw className={`h-4 w-4 mr-2 ${loading ? 'animate-spin' : ''}`} />
            Refresh
          </Button>
        }
      />

      <div className="container mx-auto px-6 py-6 max-w-5xl space-y-6">
        {/* Summary */}
        <div className="flex items-center gap-6 text-sm">
          <div className="flex items-center gap-2">
            <Building2 className="h-4 w-4 text-muted-foreground" />
            <span className="text-muted-foreground">Total companies:</span>
            <span className="font-semibold num">{total}</span>
          </div>
          <div className="flex items-center gap-2">
            <EyeOff className="h-4 w-4 text-amber-500" />
            <span className="text-muted-foreground">Excluded from analytics:</span>
            <span className="font-semibold num text-amber-600 dark:text-amber-400">{excluded}</span>
          </div>
        </div>

        <Card>
          {/* Filters */}
          <div className="flex flex-wrap items-center gap-3 p-4 border-b">
            <div className="relative flex-1 min-w-[200px] max-w-sm">
              <Search className="absolute left-2.5 top-2.5 h-4 w-4 text-muted-foreground" />
              <Input
                placeholder="Search companies…"
                value={search}
                onChange={(e) => setSearch(e.target.value)}
                className="pl-8"
              />
            </div>
            <Select value={typeFilter} onValueChange={setTypeFilter}>
              <SelectTrigger className="w-[150px]">
                <SelectValue placeholder="All types" />
              </SelectTrigger>
              <SelectContent>
                <SelectItem value="all">All types</SelectItem>
                {uniqueTypes.map((t) => (
                  <SelectItem key={t} value={String(t)}>
                    Type {t}
                  </SelectItem>
                ))}
              </SelectContent>
            </Select>
            <Select value={scopeFilter} onValueChange={(v) => setScopeFilter(v as ScopeFilter)}>
              <SelectTrigger className="w-[160px]">
                <SelectValue />
              </SelectTrigger>
              <SelectContent>
                <SelectItem value="all">All companies</SelectItem>
                <SelectItem value="in">In scope only</SelectItem>
                <SelectItem value="out">Excluded only</SelectItem>
              </SelectContent>
            </Select>
            <span className="text-xs text-muted-foreground ml-auto">
              {visible.length} shown
            </span>
          </div>

          {error && (
            <div className="p-4">
              <Alert variant="destructive">
                <AlertTitle>Failed to load</AlertTitle>
                <AlertDescription>{error}</AlertDescription>
              </Alert>
            </div>
          )}

          <CardContent className="p-0">
            {loading ? (
              <div className="p-6 space-y-3">
                {[1, 2, 3, 4, 5].map((i) => (
                  <Skeleton key={i} className="h-10 w-full" />
                ))}
              </div>
            ) : visible.length === 0 ? (
              <div className="py-12 text-center text-sm text-muted-foreground">
                No companies match the current filters.
              </div>
            ) : (
              <Table>
                <TableHeader>
                  <TableRow>
                    <TableHead>Company</TableHead>
                    <TableHead className="w-32">Type</TableHead>
                    <TableHead className="w-40 text-right">Include in analytics</TableHead>
                  </TableRow>
                </TableHeader>
                <TableBody>
                  {visible.map((company) => (
                    <TableRow
                      key={company.id}
                      className={!company.inScope ? 'opacity-50' : undefined}
                    >
                      <TableCell className="font-medium">{company.companyName}</TableCell>
                      <TableCell>
                        {company.companyTypeLabel ? (
                          <Badge variant="outline" className="text-xs">
                            {company.companyTypeLabel}
                          </Badge>
                        ) : (
                          <span className="text-muted-foreground text-xs">—</span>
                        )}
                      </TableCell>
                      <TableCell className="text-right">
                        <Switch
                          checked={company.inScope}
                          disabled={toggling === company.id}
                          onCheckedChange={(next) => void toggle(company, next)}
                          aria-label={`Include ${company.companyName} in analytics`}
                        />
                      </TableCell>
                    </TableRow>
                  ))}
                </TableBody>
              </Table>
            )}
          </CardContent>
        </Card>
      </div>
    </>
  );
}