"use client";

import type { DeadlineReport } from "@/lib/types";
import Link from "next/link";
import {
  LineChart,
  Line,
  XAxis,
  YAxis,
  CartesianGrid,
  Tooltip,
  ResponsiveContainer,
  Legend,
} from "recharts";
import { CheckCircle, XCircle, Clock, AlertTriangle } from "lucide-react";

function formatMonth(period: string): string {
  const [year, month] = period.split("-");
  const months = [
    "Jan",
    "Feb",
    "Mär",
    "Apr",
    "Mai",
    "Jun",
    "Jul",
    "Aug",
    "Sep",
    "Okt",
    "Nov",
    "Dez",
  ];
  return `${months[parseInt(month, 10) - 1]} ${year.slice(2)}`;
}

function formatDate(dateStr: string): string {
  const d = new Date(dateStr);
  return d.toLocaleDateString("de-DE", {
    day: "2-digit",
    month: "2-digit",
    year: "numeric",
  });
}

export function DeadlinesTab({ data }: { data: DeadlineReport }) {
  const chartData = data.monthly.map((m) => ({
    ...m,
    name: formatMonth(m.period),
    compliance_rate: Math.round(m.compliance_rate * 10) / 10,
  }));

  const complianceColor =
    data.total.compliance_rate >= 90
      ? "text-emerald-600"
      : data.total.compliance_rate >= 70
        ? "text-amber-600"
        : "text-red-600";

  return (
    <div className="space-y-6">
      {/* Summary cards */}
      <div className="grid grid-cols-2 gap-4 sm:grid-cols-4">
        <div className="rounded-xl border border-neutral-200 bg-white p-5">
          <div className="flex items-center gap-2 text-sm text-neutral-500">
            <Clock className="h-4 w-4" />
            Gesamt
          </div>
          <p className="mt-2 text-2xl font-semibold text-neutral-900">
            {data.total.total}
          </p>
        </div>
        <div className="rounded-xl border border-neutral-200 bg-white p-5">
          <div className="flex items-center gap-2 text-sm text-neutral-500">
            <CheckCircle className="h-4 w-4" />
            Eingehalten
          </div>
          <p className="mt-2 text-2xl font-semibold text-emerald-600">
            {data.total.met}
          </p>
        </div>
        <div className="rounded-xl border border-neutral-200 bg-white p-5">
          <div className="flex items-center gap-2 text-sm text-neutral-500">
            <XCircle className="h-4 w-4" />
            Versäumt
          </div>
          <p className="mt-2 text-2xl font-semibold text-red-600">
            {data.total.missed}
          </p>
        </div>
        <div className="rounded-xl border border-neutral-200 bg-white p-5">
          <div className="flex items-center gap-2 text-sm text-neutral-500">
            <CheckCircle className="h-4 w-4" />
            Einhaltungsquote
          </div>
          <p className={`mt-2 text-2xl font-semibold ${complianceColor}`}>
            {data.total.compliance_rate.toFixed(1)}%
          </p>
        </div>
      </div>

      {/* Compliance rate over time */}
      <div className="rounded-xl border border-neutral-200 bg-white p-5">
        <h3 className="mb-4 text-sm font-medium text-neutral-900">
          Fristeneinhaltung im Zeitverlauf
        </h3>
        {chartData.length === 0 ? (
          <p className="py-8 text-center text-sm text-neutral-400">
            Keine Daten im gewählten Zeitraum
          </p>
        ) : (
          <ResponsiveContainer width="100%" height={300}>
            <LineChart data={chartData}>
              <CartesianGrid strokeDasharray="3 3" stroke="#e5e5e5" />
              <XAxis dataKey="name" tick={{ fontSize: 12 }} stroke="#a3a3a3" />
              <YAxis
                domain={[0, 100]}
                tick={{ fontSize: 12 }}
                stroke="#a3a3a3"
                unit="%"
              />
              <Tooltip
                contentStyle={{
                  border: "1px solid #e5e5e5",
                  borderRadius: 8,
                  fontSize: 13,
                }}
                formatter={(value) => [`${value}%`, "Quote"]}
              />
              <Legend wrapperStyle={{ fontSize: 13 }} />
              <Line
                type="monotone"
                dataKey="compliance_rate"
                name="Einhaltungsquote"
                stroke="#171717"
                strokeWidth={2}
                dot={{ fill: "#171717", r: 4 }}
                activeDot={{ r: 6 }}
              />
            </LineChart>
          </ResponsiveContainer>
        )}
      </div>

      {/* Missed deadlines table */}
      <div className="rounded-xl border border-neutral-200 bg-white">
        <div className="border-b border-neutral-100 px-5 py-4">
          <h3 className="text-sm font-medium text-neutral-900">
            Versäumte Fristen
          </h3>
        </div>
        {data.missed.length === 0 ? (
          <div className="px-5 py-8 text-center">
            <CheckCircle className="mx-auto h-8 w-8 text-emerald-400" />
            <p className="mt-2 text-sm text-neutral-500">
              Keine versäumten Fristen im gewählten Zeitraum
            </p>
          </div>
        ) : (
          <div className="overflow-x-auto">
            <table className="w-full text-sm">
              <thead>
                <tr className="border-b border-neutral-100 text-left text-neutral-500">
                  <th className="px-5 py-3 font-medium">Frist</th>
                  <th className="px-5 py-3 font-medium">Akte</th>
                  <th className="px-5 py-3 font-medium">Fällig am</th>
                  <th className="px-5 py-3 font-medium text-right">
                    Tage überfällig
                  </th>
                </tr>
              </thead>
              <tbody>
                {data.missed.map((d) => (
                  <tr
                    key={d.id}
                    className="border-b border-neutral-50 last:border-b-0"
                  >
                    <td className="px-5 py-3 text-neutral-900">{d.title}</td>
                    <td className="px-5 py-3">
                      <Link
                        href={`/cases/${d.case_id}`}
                        className="text-neutral-600 hover:text-neutral-900"
                      >
                        {d.case_number} — {d.case_title}
                      </Link>
                    </td>
                    <td className="px-5 py-3 text-neutral-600">
                      {formatDate(d.due_date)}
                    </td>
                    <td className="px-5 py-3 text-right">
                      <span className="inline-flex items-center gap-1 rounded-full bg-red-50 px-2 py-0.5 text-xs font-medium text-red-700">
                        <AlertTriangle className="h-3 w-3" />
                        {d.days_overdue}
                      </span>
                    </td>
                  </tr>
                ))}
              </tbody>
            </table>
          </div>
        )}
      </div>
    </div>
  );
}