'use client';

import { useEffect, useState } from 'react';
import dynamic from 'next/dynamic';
import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
import { useTheme } from "next-themes";

// Import ApexCharts secara dinamis untuk menghindari error SSR
const Chart = dynamic(() => import('react-apexcharts'), { ssr: false });

interface MahasiswaStatistik {
  tahun_angkatan: number;
  total_mahasiswa: number;
  pria: number;
  wanita: number;
}

export default function StatistikMahasiswaChart() {
  const { theme, systemTheme } = useTheme();
  const [statistikData, setStatistikData] = useState<MahasiswaStatistik[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);
  const [chartOptions, setChartOptions] = useState({
    chart: {
      type: 'bar' as const,
      stacked: false,
      toolbar: {
        show: true,
        tools: {
          download: true,
          selection: true,
          zoom: true,
          zoomin: true,
          zoomout: true,
          pan: true,
          reset: true
        },
      },
      zoom: {
        enabled: true,
        type: 'x' as const,
        autoScaleYaxis: true
      },
    },
    markers: {
      size: 10,
      shape: 'circle' as const,
      strokeWidth: 0,
      hover: {
        size: 10
      }
    },
    plotOptions: {
      bar: {
        horizontal: false,
        columnWidth: '55%',     
      },
    },
    dataLabels: {
      enabled: true,
      formatter: function (val: number) {
        return val.toString()
      },
      position: 'top',
      style: {
        fontSize: '12px',
        colors: ['#000']
      },
    },
    stroke: {
      show: false,
      width: [0, 0, 0],
      colors: ['transparent', 'transparent', 'transparent'],
      curve: 'straight' as const
    },
    xaxis: {
      categories: [] as number[],
      title: {
        text: 'Tahun Angkatan',
        style: {
          fontSize: '14px',
          fontWeight: 'bold',
          color: '#000'
        }
      },
      labels: {
        style: {
          fontSize: '12px',
          colors: '#000'
        }
      }
    },
    yaxis: [
      {
        title: {
          text: 'Jumlah Mahasiswa',
          style: {
            fontSize: '14px',
            fontWeight: 'bold',
            color: '#000'
          }
        },
        labels: {
          style: {
            fontSize: '12px',
            colors: '#000'
          }
        },
        min:0,
        tickAmount: 5
      }
    ],
    fill: {
      opacity: 1
    },
    legend: {
      position: 'top' as const,
      fontSize: '14px',
      markers: {
        size: 12,
      },
      itemMargin: {
        horizontal: 10,
      },
      labels: {
        colors: '#000'
      }
    },
    colors: ['#3B82F6', '#10B981', '#EC4899'],
    tooltip: {
      theme: 'light',
      y: [
        {
          formatter: function (val: number) {
            return val + " mahasiswa"
          }
        },
        {
          formatter: function (val: number) {
            return val + " mahasiswa"
          }
        },
        {
          formatter: function (val: number) {
            return val + " mahasiswa"
          }
        }
      ]
    }
  });

  useEffect(() => {
    const fetchData = async () => {
      try {
        const statistikResponse = await fetch('/api/mahasiswa/statistik', {
          cache: 'no-store',
        });
        
        if (!statistikResponse.ok) {
          throw new Error('Failed to fetch statistik data');
        }
        
        const statistikData = await statistikResponse.json();
        setStatistikData(statistikData);
      } catch (err) {
        setError(err instanceof Error ? err.message : 'An error occurred');
        console.error('Error fetching data:', err);
      } finally {
        setLoading(false);
      }
    };

    fetchData();
  }, []);

  // Update theme when it changes
  useEffect(() => {
    const currentTheme = theme === 'system' ? systemTheme : theme;
    const textColor = currentTheme === 'dark' ? '#fff' : '#000';
    const tooltipTheme = currentTheme === 'dark' ? 'dark' : 'light';

    setChartOptions(prev => ({
      ...prev,
      chart: {
        ...prev.chart,
        background: currentTheme === 'dark' ? '#0F172B' : '#fff',
      },
      dataLabels: {
        ...prev.dataLabels,
        style: {
          ...prev.dataLabels.style,
          colors: [textColor]
        },
      },
      xaxis: {
        ...prev.xaxis,
        title: {
          ...prev.xaxis.title,
          style: {
            ...prev.xaxis.title.style,
            color: textColor
          }
        },
        labels: {
          ...prev.xaxis.labels,
          style: {
            ...prev.xaxis.labels.style,
            colors: textColor
          }
        }
      },
      yaxis: [
        {
          ...prev.yaxis[0],
          title: {
            ...prev.yaxis[0].title,
            style: {
              ...prev.yaxis[0].title.style,
              color: textColor
            }
          },
          labels: {
            ...prev.yaxis[0].labels,
            style: {
              ...prev.yaxis[0].labels.style,
              colors: textColor
            }
          }
        }
      ],
      legend: {
        ...prev.legend,
        labels: {
          ...prev.legend.labels,
          colors: textColor
        }
      },
      tooltip: {
        ...prev.tooltip,
        theme: tooltipTheme
      }
    }));
  }, [theme, systemTheme]);

  // Update categories when data changes
  useEffect(() => {
    if (statistikData.length > 0) {
      
      setChartOptions(prev => ({
        ...prev,
        xaxis: {
          ...prev.xaxis,
          categories: statistikData.map(item => item.tahun_angkatan)
        },
        yaxis: [
          {
            ...prev.yaxis[0],
          }
        ]
      }));
    }
  }, [statistikData]);

  const chartSeries = [
    {
      name: 'Laki-laki',
      type: 'bar' as const,
      data: statistikData.map(item => item.pria)
    },
    {
      name: 'Total',
      type: 'bar' as const,
      data: statistikData.map(item => item.total_mahasiswa)
    },
    {
      name: 'Perempuan',
      type: 'bar' as const,
      data: statistikData.map(item => item.wanita)
    }
  ];

  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 dark:text-red-400">
            Error: {error}
          </CardTitle>
        </CardHeader>
      </Card>
    );
  }

  return (
    <Card className="bg-white dark:bg-slate-900 shadow-lg">
      <CardHeader>
        <CardTitle className="text-xl font-bold dark:text-white">
          Total Mahasiswa
        </CardTitle>
      </CardHeader>
      <CardContent>
        <div className="h-[300px] sm:h-[350px] md:h-[400px] w-full max-w-5xl mx-auto">
          <Chart
            options={chartOptions}
            series={chartSeries}
            type="bar"
            height="100%"
            width="100%"
          />
        </div>
      </CardContent>
    </Card>
  );
}