import { useRouter } from 'next/router';
import { useEffect, useState, useRef } from 'react';
import Image from 'next/image';
import Link from 'next/link';
import { X } from 'lucide-react';
import { getAuth } from '~/libs/auth';
import useDevice from '@/core/hooks/useDevice';
import { createPortal } from 'react-dom';

const PagePopupInformation = () => {
  const router = useRouter();
  const isHomePage = router.pathname === '/';
  const auth = getAuth();
  const { isDesktop } = useDevice();

  const [active, setActive] = useState(false);
  const [data, setData] = useState(null);
  const [loading, setLoading] = useState(true);

  const popupRef = useRef(null);
  const [position, setPosition] = useState({ x: 20, y: window.innerHeight - 170 });
  const dragStartPos = useRef({ x: 0, y: 0 });
  const isDragging = useRef(false);
  const isTouching = useRef(false);
  const [isSnapping, setIsSnapping] = useState(false);
  const [containerLeft, setContainerLeft] = useState(0);
  
  const [isClient, setIsClient] = useState(false);

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

  useEffect(() => {
    if (isHomePage && !auth) {
      setActive(true);
      fetchData();
    }
  }, [isHomePage, auth]);

  const fetchData = async () => {
    try {
      const res = await fetch(`/api/hero-banner?type=dragable-banner`);
      const { data } = await res.json();
      if (Array.isArray(data) && data[0]?.image) {
        setData(data[0]);
      } else {
        setActive(false);
      }
    } catch (error) {
      console.error('Failed to fetch popup banner:', error);
    } finally {
      setLoading(false);
    }
  };

  useEffect(() => {
    const handleResizeOrZoom = () => {
      if (!popupRef.current) return;

      const popupWidth = popupRef.current.offsetWidth || 85;
      const popupHeight = popupRef.current.offsetHeight || 85;

      setPosition({
        x: 20,
        y: window.innerHeight - popupHeight - 20,
      });
    };

    window.addEventListener('resize', handleResizeOrZoom);

    return () => {
      window.removeEventListener('resize', handleResizeOrZoom);
    };
  }, []);


  const updateContainerLeft = () => {
    const container = document.querySelector('.container');
    if (container) {
      setContainerLeft(container.getBoundingClientRect().left);
    }
  };

  useEffect(() => {
    updateContainerLeft();
    window.addEventListener('resize', updateContainerLeft);
    window.addEventListener('scroll', updateContainerLeft);
    return () => {
      window.removeEventListener('resize', updateContainerLeft);
      window.removeEventListener('scroll', updateContainerLeft);
    };
  }, []);

  useEffect(() => {
    if (isDesktop && containerLeft) {
      const popupWidth = popupRef.current?.offsetWidth || 85;
      setPosition({
        x: containerLeft - popupWidth - 20,
        y: window.innerHeight - 130,
      });
    }
  }, [isDesktop, containerLeft]);

  const startDrag = (clientX, clientY) => {
    dragStartPos.current = { x: clientX - position.x, y: clientY - position.y };
    isDragging.current = false;
    setIsSnapping(false);
  };

  const moveDrag = (clientX, clientY) => {
    isDragging.current = true;
    const popupWidth = popupRef.current?.offsetWidth || 85;
    const popupHeight = popupRef.current?.offsetHeight || 85;
    const maxX = window.innerWidth - popupWidth - 20;

    const topPadding = isDesktop ? 0 : 130;
    const bottomPadding = isDesktop ? 0 : 80;
    const maxY = window.innerHeight - popupHeight - bottomPadding;

    const minX = 0;

    let newX = clientX - dragStartPos.current.x;
    let newY = clientY - dragStartPos.current.y;

    newX = Math.max(minX, Math.min(newX, maxX));
    newY = Math.max(topPadding, Math.min(newY, maxY));

    setPosition({ x: newX, y: newY });
  };

  const endDrag = () => {
    if (isDragging.current) {
      setIsSnapping(true);

      if (isDesktop) {
        const popupWidth = popupRef.current?.offsetWidth || 85;
        setPosition({
          x: containerLeft - popupWidth - 20,
          y: window.innerHeight - 130,
        });
      } else {
        const popupWidth = popupRef.current?.offsetWidth || 85;
        const screenMiddle = window.innerWidth / 2;

        setPosition(pos => ({
          x: pos.x + popupWidth / 2 < screenMiddle ? 20 : window.innerWidth - popupWidth - 20,
          y: pos.y,
        }));
      }
    }
    isDragging.current = false;
    isTouching.current = false;
  };



  const handleMouseDown = e => {
    e.preventDefault();
    startDrag(e.clientX, e.clientY);
    window.addEventListener('mousemove', handleMouseMove);
    window.addEventListener('mouseup', handleMouseUp);
  };

  const handleMouseMove = e => moveDrag(e.clientX, e.clientY);

  const handleMouseUp = () => {
    endDrag();
    window.removeEventListener('mousemove', handleMouseMove);
    window.removeEventListener('mouseup', handleMouseUp);
  };

  const handleTouchStart = e => {
    if (e.touches.length === 1) {
      isTouching.current = true;
      startDrag(e.touches[0].clientX, e.touches[0].clientY);
    }
  };

  useEffect(() => {
    const handleTouchMove = e => {
      if (isTouching.current) {
        e.preventDefault();
        moveDrag(e.touches[0].clientX, e.touches[0].clientY);
      }
    };

    const handleTouchEnd = () => endDrag();

    window.addEventListener('touchmove', handleTouchMove, { passive: false });
    window.addEventListener('touchend', handleTouchEnd);
    return () => {
      window.removeEventListener('touchmove', handleTouchMove);
      window.removeEventListener('touchend', handleTouchEnd);
    };
  }, []);

  if (!active || !data || loading) return null;

  const popupContent = (
    <div
      ref={popupRef}
      className={`relative pointer-events-auto ${isSnapping ? 'transition-transform duration-300 ease-out' : ''}`}
      style={{
        transform: `translate(${position.x}px, ${position.y}px)`,
        cursor: 'grab',
        width: '85px',
      }}
      onMouseDown={handleMouseDown}
      onTouchStart={handleTouchStart}
    >
      <Link
        href={typeof data.url === 'boolean' && data.url === false ? '/' : data.url}
        onClick={e => {
          if (isDragging.current) {
            e.preventDefault();
            isDragging.current = false;
          } else {
            setActive(false);
          }
        }}
        draggable="false"
      >
        <Image
          src={data.image}
          alt={data.name || 'popup'}
          width={85}
          height={85}
          className="w-full h-auto select-none"
          draggable="false"
        />
      </Link>

      <button
        onClick={() => setActive(false)}
        className="absolute -top-2 -right-2 z-10 p-1 bg-red-500 rounded-full hover:bg-red-600 transition-colors"
        aria-label="Close popup"
      >
        <X className="w-3 h-3 text-white" />
      </button>
    </div>
  );

  if (isDesktop && isClient) {
    return createPortal(
      <div className="fixed z-[9999] pointer-events-none top-0 left-0 w-screen h-screen">
        {popupContent}
      </div>,
      document.body
    );
  }

  return (
    <div className="fixed z-[9999] pointer-events-none top-[40px] left-0">
      {popupContent}
    </div>
  );
};

export default PagePopupInformation;