import { useState, useRef, useEffect, RefObject } from 'react';

interface AnimationTarget {
  x: number;
  y: number;
}

interface UseCoachModalAnimationReturn {
  // State
  isClosingModal: boolean;
  animationTarget: AnimationTarget;
  tailTarget: AnimationTarget | null;

  // Refs to attach to elements
  coachBubbleRef: RefObject<HTMLDivElement | null>;
  coachBubbleContentRef: RefObject<HTMLDivElement | null>;

  // Handlers
  handleCloseModal: () => void;

  // Animation class names
  getOverlayClassName: (baseClass: string) => string;
  getBubbleClassName: (baseClass: string) => string;
  getBubbleStyle: () => React.CSSProperties;
}

const ANIMATION_DURATION = 400;
const ESTIMATED_BUBBLE_HEIGHT = 280;

export function useCoachModalAnimation(
  showModal: boolean,
  setShowModal: (show: boolean) => void,
  triggerRef: RefObject<HTMLButtonElement | null>
): UseCoachModalAnimationReturn {
  const [isClosingModal, setIsClosingModal] = useState(false);
  const [animationTarget, setAnimationTarget] = useState<AnimationTarget>({ x: 0, y: 0 });
  const [tailTarget, setTailTarget] = useState<AnimationTarget | null>(null);

  const coachBubbleRef = useRef<HTMLDivElement>(null);
  const coachBubbleContentRef = useRef<HTMLDivElement>(null);

  // Calculate animation targets when modal opens
  useEffect(() => {
    if (showModal && !isClosingModal) {
      // Calculate animation target
      const buttonRect = triggerRef.current?.getBoundingClientRect();
      const viewportCenterX = window.innerWidth / 2;
      const viewportCenterY = window.innerHeight / 2;

      if (buttonRect) {
        const buttonCenterX = buttonRect.left + buttonRect.width / 2;
        const buttonCenterY = buttonRect.top + buttonRect.height / 2;

        setAnimationTarget({
          x: buttonCenterX - viewportCenterX,
          y: buttonCenterY - viewportCenterY,
        });

        // Calculate tail target
        const estimatedBubbleWidth = Math.min(384, window.innerWidth - 32);
        const bubbleLeft = viewportCenterX - estimatedBubbleWidth / 2;
        const bubbleBottom = viewportCenterY + ESTIMATED_BUBBLE_HEIGHT / 2;
        const buttonTargetX = buttonRect.left + buttonRect.width * 0.5;
        const buttonTopY = buttonRect.top;

        setTailTarget({
          x: buttonTargetX - bubbleLeft,
          y: buttonTopY - bubbleBottom,
        });
      }
    } else if (!showModal) {
      setTailTarget(null);
    }
  }, [showModal, isClosingModal, triggerRef]);

  const handleCloseModal = () => {
    // Recalculate animation target for closing (bubble position may have changed)
    const buttonRect = triggerRef.current?.getBoundingClientRect();
    const bubbleRect = coachBubbleRef.current?.getBoundingClientRect();

    if (buttonRect && bubbleRect) {
      const buttonCenterX = buttonRect.left + buttonRect.width / 2;
      const buttonCenterY = buttonRect.top + buttonRect.height / 2;
      const bubbleCenterX = bubbleRect.left + bubbleRect.width / 2;
      const bubbleCenterY = bubbleRect.top + bubbleRect.height / 2;

      const targetX = buttonCenterX - bubbleCenterX;
      const targetY = buttonCenterY - bubbleCenterY;

      // Set CSS variables directly on element for immediate effect (before React re-renders)
      if (coachBubbleRef.current) {
        coachBubbleRef.current.style.setProperty('--translate-x', `${targetX}px`);
        coachBubbleRef.current.style.setProperty('--translate-y', `${targetY}px`);
      }
      // Also update state to prevent React from overwriting on re-render
      setAnimationTarget({ x: targetX, y: targetY });
    }

    setIsClosingModal(true);
    // Wait for animation to complete before actually closing
    setTimeout(() => {
      setShowModal(false);
      setIsClosingModal(false);
    }, ANIMATION_DURATION);
  };

  const getOverlayClassName = (baseClass: string): string => {
    return `${baseClass} ${isClosingModal ? 'animate-fade-out' : 'animate-fade-in'}`;
  };

  const getBubbleClassName = (baseClass: string): string => {
    return `${baseClass} ${isClosingModal ? 'animate-shrink-to-coach-button' : 'animate-expand-from-coach-button'}`;
  };

  const getBubbleStyle = (): React.CSSProperties => {
    return {
      '--translate-x': `${animationTarget.x}px`,
      '--translate-y': `${animationTarget.y}px`,
    } as React.CSSProperties;
  };

  return {
    isClosingModal,
    animationTarget,
    tailTarget,
    coachBubbleRef,
    coachBubbleContentRef,
    handleCloseModal,
    getOverlayClassName,
    getBubbleClassName,
    getBubbleStyle,
  };
}