import { getCalendarPagination } from "@/service/schedule/schedule";
import React, { useEffect, useState } from "react";

interface CalendarItem {
  id: number;
  title: string;
  description: string;
  assignedTo: string;
  assignedToLevel: string;
  startDate: string; 
  endDate: string;
  isActive: boolean;
  createdById: number;
  createdByName: string;
  thumbnailUrl: string;
  createdAt: string;
  updatedAt: string;
}

const EventCalender = () => {
  // Get current date
  const today = new Date();
  const currentMonth = today.getMonth();
  const currentYear = today.getFullYear();
  const currentDate = today.getDate();

  const [events, setEvents] = useState<CalendarItem[]>([]);
  const [selectedEvent, setSelectedEvent] = useState<CalendarItem | null>(null);

  // Month names in Indonesian
  const monthNames = [
    "Januari", "Februari", "Maret", "April", "Mei", "Juni",
    "Juli", "Agustus", "September", "Oktober", "November", "Desember"
  ];

  const fetchData = async () => {
    try {
      const res = await getCalendarPagination(100, 0);
      const data = res?.data?.data;
      const contentData = data?.content;
      setEvents(contentData || []);
      
      // Set first event as selected by default
      if (contentData && contentData.length > 0) {
        setSelectedEvent(contentData[0]);
      }
    } catch (error) {
      console.error("Error fetching calendar events:", error);
    }
  };
  
  useEffect(() => {
    fetchData();
  }, []);

  // Get first day of the month and number of days
  const firstDayOfMonth = new Date(currentYear, currentMonth, 1);
  const lastDayOfMonth = new Date(currentYear, currentMonth + 1, 0);
  const daysInMonth = lastDayOfMonth.getDate();
  const startingDayOfWeek = firstDayOfMonth.getDay();
  
  // Convert Sunday (0) to 7 for Monday-first week
  const adjustedStartingDay = startingDayOfWeek === 0 ? 6 : startingDayOfWeek - 1;

  // Generate calendar days
  const generateCalendarDays = () => {
    const days = [];
    
    // Empty cells for days before the first day of month
    for (let i = 0; i < adjustedStartingDay; i++) {
      days.push(null);
    }
    
    // Days of the month
    for (let day = 1; day <= daysInMonth; day++) {
      days.push(day);
    }
    
    // Fill remaining cells to complete the grid (6 rows × 7 days = 42 cells)
    while (days.length < 42) {
      days.push(null);
    }
    
    return days;
  };

  const calendarDays = generateCalendarDays();

  // Helper function to extract day from date string
  const getDateFromString = (dateString: string) => {
    try {
      const date = new Date(dateString);
      if (date.getMonth() === currentMonth && date.getFullYear() === currentYear) {
        return date.getDate();
      }
      return null;
    } catch {
      return null;
    }
  };

  // Helper function to format date range
  const formatDateRange = (startDate: string, endDate: string) => {
    try {
      const start = new Date(startDate);
      const end = new Date(endDate);
      
      const startDay = start.getDate();
      const endDay = end.getDate();
      const startMonth = monthNames[start.getMonth()];
      const endMonth = monthNames[end.getMonth()];
      
      if (startDay === endDay && startMonth === endMonth) {
        return `${startDay} ${startMonth}`;
      } else {
        return `${startDay} ${startMonth} - ${endDay} ${endMonth}`;
      }
    } catch {
      return "Tanggal tidak valid";
    }
  };

  // Helper function to format time range
  const formatTimeRange = (startDate: string, endDate: string) => {
    try {
      const start = new Date(startDate);
      const end = new Date(endDate);
      
      const startTime = start.toLocaleTimeString('id-ID', { 
        hour: '2-digit', 
        minute: '2-digit',
        timeZone: 'Asia/Jakarta'
      });
      const endTime = end.toLocaleTimeString('id-ID', { 
        hour: '2-digit', 
        minute: '2-digit',
        timeZone: 'Asia/Jakarta'
      });
      
      return `${startTime} - ${endTime} WIB`;
    } catch {
      return "Waktu tidak tersedia";
    }
  };

  // Get event dates for highlighting calendar
  const eventDates = events
    .map(event => getDateFromString(event.startDate))
    .filter(date => date !== null);

  return (
    <div className="mt-8 rounded-lg bg-white dark:bg-zinc-900 p-4 shadow">
      <h2 className="text-lg font-bold text-red-600 border-b border-red-600 mb-4 pb-2">
        KALENDER ACARA
      </h2>
      <div className="flex flex-col lg:flex-row gap-6">
        {/* Left Side - Calendar and Event List */}
        <div className="w-full lg:w-1/2">
          {/* Mini Calendar */}
          <div className="bg-gray-100 dark:bg-zinc-800 p-4 rounded-md mb-4">
            <div className="text-center font-semibold mb-2">
              {monthNames[currentMonth]} {currentYear}
            </div>
            <div className="grid grid-cols-7 gap-1 text-sm text-center">
              {["Mo", "Tu", "We", "Th", "Fr", "Sa", "Su"].map((d) => (
                <div key={d} className="font-medium p-1">
                  {d}
                </div>
              ))}
              {calendarDays?.map((day, index) => (
                <div
                  key={index}
                  className={`p-1 rounded min-h-[24px] flex items-center justify-center text-xs ${
                    day === null 
                      ? "" 
                      : eventDates.includes(day)
                      ? "bg-red-600 text-white font-semibold"
                      : day === currentDate
                      ? "bg-blue-500 text-white font-semibold"
                      : "hover:bg-gray-200 dark:hover:bg-zinc-700"
                  }`}
                >
                  {day}
                </div>
              ))}
            </div>
          </div>

          {/* Event List */}
          <div className="space-y-3 max-h-[230px] overflow-y-auto pr-5" data-lenis-prevent>
            <h3 className="text-lg font-semibold text-gray-800 dark:text-gray-200 mb-3">
              Daftar Acara
            </h3>
            {events?.length === 0 ? (
              <div className="text-center text-gray-500 dark:text-gray-400 py-8">
                Tidak ada acara yang tersedia
              </div>
            ) : (
              events.map((event) => (
                <div
                  key={event.id}
                  onClick={() => setSelectedEvent(event)}
                  className={`flex items-center rounded-xl shadow-sm p-3 cursor-pointer transition-all duration-200 hover:shadow-md ${
                    selectedEvent?.id === event.id
                      ? "bg-red-100 dark:bg-red-900/20 border-2 border-red-500"
                      : "bg-gray-200 dark:bg-zinc-800 hover:bg-gray-300 dark:hover:bg-zinc-700"
                  }`}
                >
                  <img
                    src={event.thumbnailUrl || "/images/default-event.png"}
                    alt={event.title}
                    className="w-16 h-12 object-cover rounded flex-shrink-0"
                    onError={(e) => {
                      const target = e.target as HTMLImageElement;
                      target.src = "/images/default-event.png";
                    }}
                  />
                  <div className="ml-3 flex-1 min-w-0">
                    <div className="text-sm font-semibold text-gray-800 dark:text-gray-200 line-clamp-2">
                      {event.title}
                    </div>
                    <div className="text-xs text-gray-600 dark:text-gray-400 mt-1">
                      {formatDateRange(event.startDate, event.endDate)}
                    </div>
                  </div>
                  <div className="ml-2 flex-shrink-0">
                    <div className={`w-2 h-2 rounded-full ${event.isActive ? 'bg-green-500' : 'bg-red-500'}`}></div>
                  </div>
                </div>
              ))
            )}
          </div>
        </div>

        {/* Right Side - Event Detail */}
        <div className="w-full lg:w-1/2">
          <div className="bg-gray-100 dark:bg-zinc-800 rounded-lg p-4 sticky top-4">
            <h3 className="text-lg font-semibold text-gray-800 dark:text-gray-200 mb-4">
              Detail Acara
            </h3>
            
            {selectedEvent ? (
              <div className="space-y-4">
                <img
                  src={selectedEvent.thumbnailUrl || "/images/default-event.png"}
                  alt={selectedEvent.title}
                  className="w-full h-48 object-cover rounded-lg"
                  onError={(e) => {
                    const target = e.target as HTMLImageElement;
                    target.src = "/images/default-event.png";
                  }}
                />
                
                <div>
                  <h4 className="text-lg font-bold text-gray-800 dark:text-gray-200 mb-2">
                    {selectedEvent.title}
                  </h4>
                  
                  <div className="grid grid-cols-1 gap-3 mb-4">
                    <div className="flex items-start text-sm text-gray-600 dark:text-gray-400">
                      <span className="w-20 font-semibold flex-shrink-0">Tanggal:</span>
                      <span>{formatDateRange(selectedEvent.startDate, selectedEvent.endDate)}</span>
                    </div>
                    <div className="mb-4">
                      <p className="text-sm text-gray-600 dark:text-gray-400 leading-relaxed">
                        {selectedEvent.description || "Tidak ada deskripsi tersedia."}
                      </p>
                    </div>
                  </div>
                  
                  <div className="flex gap-2">
                    <button className="px-4 py-2 bg-gray-300 dark:bg-zinc-700 text-gray-700 dark:text-gray-300 text-sm font-medium rounded-lg hover:bg-gray-400 dark:hover:bg-zinc-600 transition-colors">
                      Bagikan
                    </button>
                  </div>
                </div>
              </div>
            ) : (
              <div className="text-center text-gray-500 dark:text-gray-400 py-8">
                Pilih acara untuk melihat detail
              </div>
            )}
          </div>
        </div>
      </div>
    </div>
  );
};

export default EventCalender;