'use client';

import { ClipboardList } from 'lucide-react';
import * as React from 'react';
import { CreateLeadDialog } from '@/components/leads/create-lead-dialog';
import { LeadDetailDialog } from '@/components/leads/lead-detail-dialog';
import { LeadStatusBadge } from '@/components/leads/lead-status-badge';
import { Button } from '@/components/ui/button';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Select } from '@/components/ui/select';
import { useLeads, useLeadStats } from '@/lib/hooks/use-leads';
import { LEAD_STATUSES, LEAD_SOURCES, type LeadReadDto, type LeadStatus } from '@/lib/leads-api';

function getSourceLabel(source: string): string {
  const found = LEAD_SOURCES.find((s) => s.value === source);
  return found?.label ?? source;
}

function formatDate(dateStr: string): string {
  return new Date(dateStr).toLocaleDateString('vi-VN', {
    day: '2-digit',
    month: '2-digit',
    year: 'numeric',
  });
}

export default function LeadsPage() {
  const [page, setPage] = React.useState(1);
  const [statusFilter, setStatusFilter] = React.useState<LeadStatus | ''>('');
  const [createOpen, setCreateOpen] = React.useState(false);
  const [selectedLead, setSelectedLead] = React.useState<LeadReadDto | null>(null);
  const [detailOpen, setDetailOpen] = React.useState(false);

  const searchParams = React.useMemo(() => {
    const params: { page: number; limit: number; status?: LeadStatus } = { page, limit: 20 };
    if (statusFilter) params.status = statusFilter;
    return params;
  }, [page, statusFilter]);

  const { data: result, isLoading: loading } = useLeads(searchParams);
  const { data: stats, isLoading: statsLoading } = useLeadStats();

  const handleSelectLead = (lead: LeadReadDto) => {
    setSelectedLead(lead);
    setDetailOpen(true);
  };

  return (
    <div className="space-y-6">
      {/* Header */}
      <div className="flex flex-col gap-4 sm:flex-row sm:items-center sm:justify-between">
        <div>
          <h1 className="text-2xl font-bold">Quản lý lead</h1>
          <p className="text-sm text-muted-foreground">
            Theo dõi và chuyển đổi khách hàng tiềm năng
          </p>
        </div>
        <Button onClick={() => setCreateOpen(true)}>Thêm lead</Button>
      </div>

      {/* Stats */}
      <div className="grid grid-cols-2 gap-3 sm:grid-cols-4">
        <Card>
          <CardHeader className="pb-2">
            <CardDescription>Tổng lead</CardDescription>
            <CardTitle className="text-xl">
              {statsLoading ? '...' : stats?.totalLeads ?? 0}
            </CardTitle>
          </CardHeader>
        </Card>
        <Card>
          <CardHeader className="pb-2">
            <CardDescription>Tỷ lệ chuyển đổi</CardDescription>
            <CardTitle className="text-xl text-green-600">
              {statsLoading ? '...' : `${(stats?.conversionRate ?? 0).toFixed(1)}%`}
            </CardTitle>
          </CardHeader>
        </Card>
        <Card>
          <CardHeader className="pb-2">
            <CardDescription>Điểm TB</CardDescription>
            <CardTitle className="text-xl text-blue-600">
              {statsLoading ? '...' : stats?.avgScore !== null ? stats?.avgScore?.toFixed(0) : 'N/A'}
            </CardTitle>
          </CardHeader>
        </Card>
        <Card>
          <CardHeader className="pb-2">
            <CardDescription>Lead mới</CardDescription>
            <CardTitle className="text-xl text-yellow-600">
              {statsLoading ? '...' : stats?.byStatus?.['NEW'] ?? 0}
            </CardTitle>
          </CardHeader>
        </Card>
      </div>

      {/* Status breakdown */}
      {stats && !statsLoading && (
        <div className="flex flex-wrap gap-2">
          {Object.entries(stats.byStatus).map(([status, count]) => {
            const config = LEAD_STATUSES[status as LeadStatus];
            if (!config || count === 0) return null;
            return (
              <button
                key={status}
                onClick={() => {
                  setStatusFilter(status === statusFilter ? '' : (status as LeadStatus));
                  setPage(1);
                }}
                className={`inline-flex items-center gap-1.5 rounded-full border px-3 py-1 text-sm transition-colors hover:bg-accent ${
                  status === statusFilter ? 'bg-accent border-primary' : ''
                }`}
              >
                <LeadStatusBadge status={status as LeadStatus} />
                <span className="text-muted-foreground">{count}</span>
              </button>
            );
          })}
        </div>
      )}

      {/* Filters */}
      <div className="flex items-center gap-3">
        <Select
          value={statusFilter}
          onChange={(e) => {
            setStatusFilter(e.target.value as LeadStatus | '');
            setPage(1);
          }}
          className="w-44"
        >
          <option value="">Tất cả trạng thái</option>
          {Object.entries(LEAD_STATUSES).map(([value, { label }]) => (
            <option key={value} value={value}>
              {label}
            </option>
          ))}
        </Select>
        {result && (
          <span className="text-sm text-muted-foreground">
            {result.total} lead
          </span>
        )}
      </div>

      {/* Content */}
      {loading ? (
        <div className="flex min-h-[300px] items-center justify-center">
          <div className="h-8 w-8 animate-spin rounded-full border-4 border-primary border-t-transparent" />
        </div>
      ) : !result || result.data.length === 0 ? (
        <div className="flex min-h-[300px] flex-col items-center justify-center text-muted-foreground">
          <ClipboardList className="h-10 w-10 text-muted-foreground mb-3" aria-hidden="true" />
          <p>Chưa có lead nào</p>
          <Button variant="outline" size="sm" className="mt-3" onClick={() => setCreateOpen(true)}>
            Thêm lead đầu tiên
          </Button>
        </div>
      ) : (
        <>
          {/* Mobile card view */}
          <div className="space-y-3 sm:hidden">
            {result.data.map((lead) => (
              <Card
                key={lead.id}
                className="cursor-pointer transition-shadow hover:shadow-md"
                onClick={() => handleSelectLead(lead)}
              >
                <CardContent className="p-4">
                  <div className="flex items-start justify-between gap-2">
                    <div className="min-w-0 flex-1">
                      <p className="font-medium">{lead.name}</p>
                      <p className="text-xs text-muted-foreground">{lead.phone}</p>
                    </div>
                    <LeadStatusBadge status={lead.status} />
                  </div>
                  <div className="mt-2 flex flex-wrap gap-2 text-xs text-muted-foreground">
                    <span>{getSourceLabel(lead.source)}</span>
                    {lead.score !== null && <span>Điểm: {lead.score}</span>}
                    <span>{formatDate(lead.createdAt)}</span>
                  </div>
                </CardContent>
              </Card>
            ))}
          </div>

          {/* Desktop table view */}
          <Card className="hidden sm:block">
            <CardContent className="p-0">
              <div className="overflow-x-auto">
                <table className="w-full text-sm">
                  <thead>
                    <tr className="border-b text-left">
                      <th className="p-3 font-medium">Khách hàng</th>
                      <th className="p-3 font-medium">Nguồn</th>
                      <th className="p-3 font-medium text-center">Điểm</th>
                      <th className="p-3 font-medium text-center">Trạng thái</th>
                      <th className="p-3 font-medium text-right">Ngày tạo</th>
                      <th className="p-3 font-medium text-right">Cập nhật</th>
                    </tr>
                  </thead>
                  <tbody>
                    {result.data.map((lead) => (
                      <tr
                        key={lead.id}
                        className="border-b last:border-0 cursor-pointer transition-colors hover:bg-accent/50"
                        onClick={() => handleSelectLead(lead)}
                      >
                        <td className="p-3">
                          <div className="flex flex-col gap-0.5">
                            <span className="font-medium">{lead.name}</span>
                            <span className="text-xs text-muted-foreground">{lead.phone}</span>
                            {lead.email && (
                              <span className="text-xs text-muted-foreground">{lead.email}</span>
                            )}
                          </div>
                        </td>
                        <td className="p-3 text-muted-foreground">
                          {getSourceLabel(lead.source)}
                        </td>
                        <td className="p-3 text-center">
                          {lead.score !== null ? (
                            <div className="flex flex-col items-center gap-1">
                              <span className="font-medium">{lead.score}</span>
                              <div className="h-1 w-12 rounded-full bg-muted">
                                <div
                                  className="h-1 rounded-full bg-primary"
                                  style={{ width: `${lead.score}%` }}
                                />
                              </div>
                            </div>
                          ) : (
                            <span className="text-muted-foreground">—</span>
                          )}
                        </td>
                        <td className="p-3 text-center">
                          <LeadStatusBadge status={lead.status} />
                        </td>
                        <td className="p-3 text-right text-xs text-muted-foreground">
                          {formatDate(lead.createdAt)}
                        </td>
                        <td className="p-3 text-right text-xs text-muted-foreground">
                          {formatDate(lead.updatedAt)}
                        </td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            </CardContent>
          </Card>
        </>
      )}

      {/* Pagination */}
      {result && result.totalPages > 1 && (
        <div className="flex items-center justify-center gap-2">
          <Button
            variant="outline"
            size="sm"
            disabled={page <= 1}
            onClick={() => setPage((p) => p - 1)}
          >
            Trước
          </Button>
          <span className="text-sm text-muted-foreground">
            Trang {result.page} / {result.totalPages}
          </span>
          <Button
            variant="outline"
            size="sm"
            disabled={page >= result.totalPages}
            onClick={() => setPage((p) => p + 1)}
          >
            Tiếp
          </Button>
        </div>
      )}

      {/* Dialogs */}
      <CreateLeadDialog open={createOpen} onOpenChange={setCreateOpen} />
      <LeadDetailDialog
        lead={selectedLead}
        open={detailOpen}
        onOpenChange={(open) => {
          setDetailOpen(open);
          if (!open) setSelectedLead(null);
        }}
      />
    </div>
  );
}