'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 MKBelumDiambilData {
  tahun_angkatan: number;
  jenis_mk: string;
  jumlah_belum_diambil: number;
  total_mata_kuliah: number;
  total_mahasiswa: number;
}

interface MKBelumDiambilChartProps {
  selectedYear?: string;
  height?: string;
  showDetailButton?: boolean;
}

export default function MKBelumDiambilChart({ 
  selectedYear = 'all',
  height = "h-[300px] sm:h-[350px] md:h-[300px]",
  showDetailButton = true 
}: MKBelumDiambilChartProps) {
  const { theme } = useTheme();
  const [mounted, setMounted] = useState(false);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);
  const [data, setData] = useState<MKBelumDiambilData[]>([]);
  const [series, setSeries] = useState<ApexAxisChartSeries>([]);
  const [options, setOptions] = useState<ApexOptions>({
    chart: {
      type: 'bar',
      stacked: true,
      toolbar: {
        show: true,
      },
      background: theme === 'dark' ? '#0F172B' : '#fff',
    },
    plotOptions: {
      bar: {
        horizontal: true,
        barHeight: '70%',
      },
    },
    dataLabels: {
      enabled: true,
      formatter: function (val: number, opts: any) {
        const dataPointIndex = opts.dataPointIndex;
        
        // Hitung total untuk tahun angkatan ini
        const allSeries = opts.w.config.series;
        let totalForYear = 0;
        allSeries.forEach((series: any) => {
          totalForYear += series.data[dataPointIndex] || 0;
        });
        
        if (totalForYear === 0 || val === 0) return '';
        
        const percentage = ((val / totalForYear) * 100).toFixed(0);
        return percentage + '%';
      },
      style: {
        fontSize: '12px',
        colors: [theme === 'dark' ? '#fff' : '#000']
      }
    },
    stroke: {
      show: true,
      width: 2,
      colors: ['transparent'],
    },
    xaxis: {
      categories: [],
      title: {
        text: 'Jumlah Mata Kuliah Belum Diambil',
        style: {
          fontSize: '14px',
          fontWeight: 'bold',
          color: theme === 'dark' ? '#fff' : '#000'
        }
      },
      labels: {
        style: {
          fontSize: '12px',
          colors: theme === 'dark' ? '#fff' : '#000'
        }
      },
      min: 0,
      tickAmount: 5
    },
    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: ['#3B82F6', '#10B981', '#F59E0B'], // Wajib (blue), Pilihan Wajib (green), Pilihan (amber)
    tooltip: {
      theme: theme === 'dark' ? 'dark' : 'light',
      shared: true,
      intersect: false,
      custom: function({ series, seriesIndex, dataPointIndex, w }: any) {
        const tahun = w.globals.labels[dataPointIndex];
        const isDark = theme === 'dark';
        
        // Hitung total untuk tahun ini
        let total = 0;
        series.forEach((seriesData: number[]) => {
          total += seriesData[dataPointIndex] || 0;
        });
        
        const jenisMKNames = w.config.series.map((s: any) => s.name);
        const jenisMKColors = w.config.colors;
        
        let tooltipContent = `
          <div style="
            padding: 12px 16px; 
            background: ${isDark ? 'rgba(30, 41, 59, 0.95)' : 'rgba(255, 255, 255, 0.95)'}; 
            backdrop-filter: blur(10px);
            border: none; 
            border-radius: 12px; 
            box-shadow: 0 8px 32px ${isDark ? 'rgba(0, 0, 0, 0.3)' : 'rgba(0, 0, 0, 0.1)'};
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            min-width: 200px;
          ">
            <div style="
              font-size: 13px; 
              font-weight: 600; 
              color: ${isDark ? '#f1f5f9' : '#1f2937'}; 
              margin-bottom: 8px;
              text-align: center;
            ">Angkatan ${tahun}</div>`;
        
        // Tambahkan setiap jenis MK
        series.forEach((seriesData: number[], index: number) => {
          const value = seriesData[dataPointIndex] || 0;
          if (value > 0) {
            const percentage = total > 0 ? ((value / total) * 100).toFixed(1) : '0';
            tooltipContent += `
              <div style="display: flex; align-items: center; margin-bottom: 4px;">
                <div style="width: 8px; height: 8px; background: ${jenisMKColors[index]}; border-radius: 50%; margin-right: 8px;"></div>
                <span style="font-size: 12px; color: ${isDark ? '#cbd5e1' : '#374151'};">${jenisMKNames[index]}</span>
                <span style="font-size: 12px; font-weight: 600; color: ${isDark ? '#f1f5f9' : '#1f2937'}; margin-left: auto;">${value} (${percentage}%)</span>
              </div>`;
          }
        });
        
        // Tambahkan total
        tooltipContent += `
            <div style="
              border-top: 1px solid ${isDark ? '#475569' : '#e5e7eb'}; 
              margin-top: 8px; 
              padding-top: 8px;
              display: flex; 
              align-items: center;
            ">
              <div style="width: 8px; height: 8px; background: #6366f1; border-radius: 50%; margin-right: 8px;"></div>
              <span style="font-size: 12px; font-weight: 600; color: ${isDark ? '#f1f5f9' : '#1f2937'};">Total MK Belum Diambil</span>
              <span style="font-size: 13px; font-weight: 700; color: #6366f1; margin-left: auto;">${total}</span>
            </div>
          </div>
        `;
        
        return tooltipContent;
      }
    }
  });

  // Update theme when it changes
  useEffect(() => {
    const currentTheme = theme;
    setOptions(prev => ({
      ...prev,
      chart: {
        ...prev.chart,
        background: currentTheme === 'dark' ? '#0F172B' : '#fff',
      },
      dataLabels: {
        ...prev.dataLabels,
        formatter: function (val: number, opts: any) {
          const dataPointIndex = opts.dataPointIndex;
          
          // Hitung total untuk tahun angkatan ini
          const allSeries = opts.w.config.series;
          let totalForYear = 0;
          allSeries.forEach((series: any) => {
            totalForYear += series.data[dataPointIndex] || 0;
          });
          
          if (totalForYear === 0 || val === 0) return '';
          
          const percentage = ((val / totalForYear) * 100).toFixed(0);
          return percentage + '%';
        },
        style: {
          ...prev.dataLabels?.style,
          colors: [currentTheme === 'dark' ? '#fff' : '#000']
        }
      },
      xaxis: {
        ...prev.xaxis,
        title: {
          ...prev.xaxis?.title,
          style: {
            ...prev.xaxis?.title?.style,
            color: currentTheme === 'dark' ? '#fff' : '#000'
          }
        },
        labels: {
          ...prev.xaxis?.labels,
          style: {
            ...prev.xaxis?.labels?.style,
            colors: currentTheme === 'dark' ? '#fff' : '#000'
          }
        }
      },
      yaxis: {
        ...prev.yaxis,
        title: {
          ...(Array.isArray(prev.yaxis) ? prev.yaxis[0]?.title : prev.yaxis?.title),
          style: {
            ...(Array.isArray(prev.yaxis) ? prev.yaxis[0]?.title?.style : prev.yaxis?.title?.style),
            color: currentTheme === 'dark' ? '#fff' : '#000'
          }
        },
        labels: {
          ...(Array.isArray(prev.yaxis) ? prev.yaxis[0]?.labels : prev.yaxis?.labels),
          style: {
            ...(Array.isArray(prev.yaxis) ? prev.yaxis[0]?.labels?.style : prev.yaxis?.labels?.style),
            colors: currentTheme === 'dark' ? '#fff' : '#000'
          }
        }
      },
      legend: {
        ...prev.legend,
        labels: {
          ...prev.legend?.labels,
          colors: currentTheme === 'dark' ? '#fff' : '#000'
        }
      },
      tooltip: {
        ...prev.tooltip,
        theme: currentTheme === 'dark' ? 'dark' : 'light',
        custom: function({ series, seriesIndex, dataPointIndex, w }: any) {
          const tahun = w.globals.labels[dataPointIndex];
          const isDark = currentTheme === 'dark';
          
          // Hitung total untuk tahun ini
          let total = 0;
          series.forEach((seriesData: number[]) => {
            total += seriesData[dataPointIndex] || 0;
          });
          
          const jenisMKNames = w.config.series.map((s: any) => s.name);
          const jenisMKColors = w.config.colors;
          
          let tooltipContent = `
            <div style="
              padding: 12px 16px; 
              background: ${isDark ? 'rgba(30, 41, 59, 0.95)' : 'rgba(255, 255, 255, 0.95)'}; 
              backdrop-filter: blur(10px);
              border: none; 
              border-radius: 12px; 
              box-shadow: 0 8px 32px ${isDark ? 'rgba(0, 0, 0, 0.3)' : 'rgba(0, 0, 0, 0.1)'};
              font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
              min-width: 200px;
            ">
              <div style="
                font-size: 13px; 
                font-weight: 600; 
                color: ${isDark ? '#f1f5f9' : '#1f2937'}; 
                margin-bottom: 8px;
                text-align: center;
              ">Angkatan ${tahun}</div>`;
          
          // Tambahkan setiap jenis MK
          series.forEach((seriesData: number[], index: number) => {
            const value = seriesData[dataPointIndex] || 0;
            if (value > 0) {
              const percentage = total > 0 ? ((value / total) * 100).toFixed(1) : '0';
              tooltipContent += `
                <div style="display: flex; align-items: center; margin-bottom: 4px;">
                  <div style="width: 8px; height: 8px; background: ${jenisMKColors[index]}; border-radius: 50%; margin-right: 8px;"></div>
                  <span style="font-size: 12px; color: ${isDark ? '#cbd5e1' : '#374151'};">${jenisMKNames[index]}</span>
                  <span style="font-size: 12px; font-weight: 600; color: ${isDark ? '#f1f5f9' : '#1f2937'}; margin-left: auto;">${value} (${percentage}%)</span>
                </div>`;
            }
          });
          
          // Tambahkan total
          tooltipContent += `
              <div style="
                border-top: 1px solid ${isDark ? '#475569' : '#e5e7eb'}; 
                margin-top: 8px; 
                padding-top: 8px;
                display: flex; 
                align-items: center;
              ">
                <div style="width: 8px; height: 8px; background: #6366f1; border-radius: 50%; margin-right: 8px;"></div>
                <span style="font-size: 12px; font-weight: 600; color: ${isDark ? '#f1f5f9' : '#1f2937'};">Total MK Belum Diambil</span>
                <span style="font-size: 13px; font-weight: 700; color: #6366f1; margin-left: auto;">${total}</span>
              </div>
            </div>
          `;
          
          return tooltipContent;
        }
      }
    }));
  }, [theme]);

  useEffect(() => {
    setMounted(true);
  }, []);

  useEffect(() => {
    const fetchData = async () => {
      try {
        setLoading(true);
        setError(null);
        
        const url = selectedYear === 'all'
          ? '/api/mahasiswa/mkbelumdiambil'
          : `/api/mahasiswa/mkbelumdiambil?tahun_angkatan=${selectedYear}`;
        
        const response = await fetch(url);
        
        if (!response.ok) {
          throw new Error(`Failed to fetch data: ${response.status} ${response.statusText}`);
        }
        
        const result = await response.json();
        
        if (!Array.isArray(result)) {
          throw new Error('Invalid data format received from server');
        }
        
        setData(result);

        // Ambil tahun angkatan unik dan urutkan
        const tahunAngkatan = [...new Set(result.map(item => item.tahun_angkatan))].sort((a, b) => a - b);
        
        // Ambil jenis MK unik dan urutkan sesuai urutan: Wajib, Pilihan Wajib, Pilihan
        const jenisMKOrder = ['Wajib', 'Pilihan Wajib', 'Pilihan'];
        const jenisMK = [...new Set(result.map(item => item.jenis_mk))].sort((a, b) => {
          return jenisMKOrder.indexOf(a) - jenisMKOrder.indexOf(b);
        });
        
        // Buat series data
        const seriesData = jenisMK.map(jenis => ({
          name: jenis,
          data: tahunAngkatan.map(tahun => {
            const item = result.find(d => d.tahun_angkatan === tahun && d.jenis_mk === jenis);
            return item ? item.jumlah_belum_diambil : 0;
          }),
        }));

        setSeries(seriesData);
        
        setOptions(prev => ({
          ...prev,
          xaxis: {
            ...prev.xaxis,
            categories: tahunAngkatan,
          },
        }));
      } catch (err) {
        console.error('Error in fetchData:', err);
        setError(err instanceof Error ? err.message : 'An error occurred while fetching data');
      } finally {
        setLoading(false);
      }
    };

    fetchData();
  }, [selectedYear]);

  if (!mounted) {
    return null;
  }

  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>
    );
  }

  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">
            Mata Kuliah Belum Diambil
            {selectedYear !== 'all' ? ` Angkatan ${selectedYear}` : ''}
          </CardTitle>
        </CardHeader>
        <CardContent>
          <p className="text-sm text-muted-foreground">
            Tidak ada data yang tersedia untuk periode ini.
          </p>
        </CardContent>
      </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">
            Mata Kuliah Belum Diambil Berdasarkan Jenis MK
            {selectedYear !== 'all' ? ` Angkatan ${selectedYear}` : ''}
          </CardTitle>
          {showDetailButton && (
            <Link href="/detail/mk-belum-diambil" target="_blank">
              <Button variant="outline" size="sm" className="flex items-center gap-1 dark:text-white">
                <ExternalLink className="size-3" />
                Detail
              </Button>
            </Link>
          )}
        </div>
      </CardHeader>
      <CardContent>
        <div className={`${height} w-full max-w-5xl mx-auto`}>
          <Chart
            options={options}
            series={series}
            type="bar"
            height="100%"
            width="100%"
          />
        </div>
      </CardContent>
    </Card>
  );
}