'use client';

import { useEffect, useState } from 'react';
import dynamic from 'next/dynamic';
import { ApexOptions } from 'apexcharts';
import { useTheme } from 'next-themes';
import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
import { Button } from "@/components/ui/button";
import { ExternalLink } from "lucide-react";
import Link from "next/link";

const Chart = dynamic(() => import('react-apexcharts'), { ssr: false });

interface KelompokKeahlianStatusData {
  tahun_angkatan: number;
  nama_kelompok: string;
  jumlah_mahasiswa: number;
}

interface Props {
  selectedYear: string;
}

interface KelompokKeahlianStatusChartProps extends Props {
  height?: string;
  showDetailButton?: boolean;
}

export default function KelompokKeahlianStatusChart({ 
  selectedYear, 
  height = "h-[300px] sm:h-[300px] md:h-[300px]",
  showDetailButton = true 
}: KelompokKeahlianStatusChartProps) {
  const { theme } = useTheme();
  const [data, setData] = useState<KelompokKeahlianStatusData[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);

  useEffect(() => {
    const fetchData = async () => {
      try {
        setLoading(true);
        const response = await fetch(
          `/api/mahasiswa/kk-dashboard?tahun_angkatan=${selectedYear}`
        );
        if (!response.ok) {
          throw new Error('Failed to fetch data');
        }
        const result = await response.json();
        const sortedData = result.sort((a: KelompokKeahlianStatusData, b: KelompokKeahlianStatusData) => 
          a.nama_kelompok.localeCompare(b.nama_kelompok)
        );
        setData(sortedData);
      } catch (err) {
        setError(err instanceof Error ? err.message : 'An error occurred');
      } finally {
        setLoading(false);
      }
    };
    fetchData();
  }, [selectedYear]);

  // Get unique tahun_angkatan (series)
  const years = [...new Set(data.map(item => item.tahun_angkatan))].sort((a, b) => Number(a) - Number(b));
  // Get unique kelompok keahlian (x axis)
  const kelompokList = [...new Set(data.map(item => item.nama_kelompok))];

  // Process data for series
  const processSeriesData = () => {
    return kelompokList.map(kelompok => {
      const seriesData = years.map(tahun => {
        const found = data.find(item => item.tahun_angkatan === tahun && item.nama_kelompok === kelompok);
        return found ? found.jumlah_mahasiswa : 0;
      });
      return {
        name: kelompok,
        data: seriesData
      };
    });
  };

  const series = processSeriesData();

  const chartOptions: ApexOptions = {
    chart: {
      type: 'bar',
      stacked: true,
      toolbar: {
        show: true,
      },
      background: theme === 'dark' ? '#0F172B' : '#fff',
    },
    plotOptions: {
      bar: {
        horizontal: true,
        columnWidth: '55%',
      },
    },
    dataLabels: {
      enabled: true,
      formatter: function (val: number) {
        return val.toString();
      },
      style: {
        fontSize: '12px',
        colors: [theme === 'dark' ? '#fff' : '#000']
      }
    },
    stroke: {
      show: true,
      width: 2,
      colors: ['transparent'],
    },
    xaxis: {
        categories: years.map(y => y.toString()),
        title: {
          text: 'Jumlah Mahasiswa',
        style: {
          fontSize: '14px',
          fontWeight: 'bold',
          color: theme === 'dark' ? '#fff' : '#000'
        }
      },
      labels: {
        style: {
          fontSize: '12px',
          colors: theme === 'dark' ? '#fff' : '#000'
        }
      }
    },
    yaxis: {
      title: {
        text: 'Tahun Angkatan',
        style: {
          fontSize: '14px',
          fontWeight: 'bold',
          color: theme === 'dark' ? '#fff' : '#000'
        }
      },
      labels: {
        style: {
          fontSize: '12px',
          colors: theme === 'dark' ? '#fff' : '#000'
        }
      },
    },
    fill: {
      opacity: 1,
    },
    legend: {
      position: 'top',
      fontSize: '14px',
      markers: {
        size: 12,
      },
      itemMargin: {
        horizontal: 10,
      },
      labels: {
        colors: theme === 'dark' ? '#fff' : '#000'
      }
    },
    colors: ['#008FFB', '#00E396', '#FEB019', '#FF4560', '#775DD0', '#8B5CF6', '#EC4899', '#06B6D4', '#F97316'],
    tooltip: {
      theme: theme === 'dark' ? 'dark' : 'light',
      y: {
        formatter: function (val: number) {
          return val + ' mahasiswa';
        }
      }
    }
  };

  if (loading) {
    return (
      <Card className="bg-white dark:bg-slate-900 shadow-lg">
        <CardHeader>
          <CardTitle className="text-xl font-bold dark:text-white">
            Loading...
          </CardTitle>
        </CardHeader>
      </Card>
    );
  }

  if (error) {
    return (
      <Card className="bg-white dark:bg-slate-900 shadow-lg">
        <CardHeader>
          <CardTitle className="text-xl font-bold text-red-500">
            Error: {error}
          </CardTitle>
        </CardHeader>
      </Card>
    );
  }

  if (data.length === 0) {
    return (
      <Card className="bg-white dark:bg-slate-900 shadow-lg">
        <CardHeader>
          <CardTitle className="text-xl font-bold dark:text-white">
            Tidak ada data yang tersedia
          </CardTitle>
        </CardHeader>
      </Card>
    );
  }

  return (
    <Card className="bg-white dark:bg-slate-900 shadow-lg">
      <CardHeader>
        <div className="flex justify-between items-center">
          <CardTitle className="text-xl font-bold dark:text-white">
            Kelompok Keahlian Mahasiswa
            {selectedYear !== 'all' ? ` Angkatan ${selectedYear}` : ''}
          </CardTitle>
          {showDetailButton && (
            <Link href="/detail/kelompok-keahlian" target="_blank">
              <Button variant="outline" size="sm" className="flex items-center gap-1 dark:text-white">
                <ExternalLink className="size-3" />
                Detail
              </Button>
            </Link>
          )}
        </div>
      </CardHeader>
      <CardContent>
        <div className={`${height} w-full max-w-5xl mx-auto`}>
          {typeof window !== 'undefined' && (
            <Chart
              options={chartOptions}
              series={series}
              type="bar"
              height="100%"
              width="100%"
            />
          )}
        </div>
      </CardContent>
    </Card>
  );
}