import { Animation } from '../../../interface';
import { createAnimation } from '../../../utils/animation/animation';

/**
 * Md Popover Enter Animation
 */
export const mdEnterAnimation = (baseEl: HTMLElement, ev?: Event): Animation => {
  const POPOVER_MD_BODY_PADDING = 12;
  const doc = (baseEl.ownerDocument as any);
  const isRTL = doc.dir === 'rtl';

  let originY = 'top';
  let originX = isRTL ? 'right' : 'left';

  const contentEl = baseEl.querySelector('.popover-content') as HTMLElement;
  const contentDimentions = contentEl.getBoundingClientRect();
  const contentWidth = contentDimentions.width;
  const contentHeight = contentDimentions.height;

  const bodyWidth = doc.defaultView.innerWidth;
  const bodyHeight = doc.defaultView.innerHeight;

  // If ev was passed, use that for target element
  const targetDim =
    ev && ev.target && (ev.target as HTMLElement).getBoundingClientRect();

  // As per MD spec, by default position the popover below the target (trigger) element
  const targetTop =
    targetDim != null && 'bottom' in targetDim
      ? targetDim.bottom
      : bodyHeight / 2 - contentHeight / 2;

  const targetLeft =
    targetDim != null && 'left' in targetDim
      ? isRTL
        ? targetDim.left - contentWidth + targetDim.width
        : targetDim.left
      : bodyWidth / 2 - contentWidth / 2;

  const targetHeight = (targetDim && targetDim.height) || 0;

  const popoverCSS: { top: any; left: any } = {
    top: targetTop,
    left: targetLeft
  };

  // If the popover left is less than the padding it is off screen
  // to the left so adjust it, else if the width of the popover
  // exceeds the body width it is off screen to the right so adjust
  if (popoverCSS.left < POPOVER_MD_BODY_PADDING) {
    popoverCSS.left = POPOVER_MD_BODY_PADDING;

    // Same origin in this case for both LTR & RTL
    // Note: in LTR, originX is already 'left'
    originX = 'left';
  } else if (
    contentWidth + POPOVER_MD_BODY_PADDING + popoverCSS.left >
    bodyWidth
  ) {
    popoverCSS.left = bodyWidth - contentWidth - POPOVER_MD_BODY_PADDING;

    // Same origin in this case for both LTR & RTL
    // Note: in RTL, originX is already 'right'
    originX = 'right';
  }

  // If the popover when popped down stretches past bottom of screen,
  // make it pop up if there's room above
  if (
    targetTop + targetHeight + contentHeight > bodyHeight &&
    targetTop - contentHeight > 0
  ) {
    popoverCSS.top = targetTop - contentHeight - targetHeight;
    baseEl.className = baseEl.className + ' popover-bottom';
    originY = 'bottom';
    // If there isn't room for it to pop up above the target cut it off
  } else if (targetTop + targetHeight + contentHeight > bodyHeight) {
    contentEl.style.bottom = POPOVER_MD_BODY_PADDING + 'px';
  }

  const baseAnimation = createAnimation();
  const backdropAnimation = createAnimation();
  const wrapperAnimation = createAnimation();
  const contentAnimation = createAnimation();
  const viewportAnimation = createAnimation();

  backdropAnimation
    .addElement(baseEl.querySelector('ion-backdrop')!)
    .fromTo('opacity', 0.01, 'var(--backdrop-opacity)')
    .beforeStyles({
      'pointer-events': 'none'
    })
    .afterClearStyles(['pointer-events']);

  wrapperAnimation
    .addElement(baseEl.querySelector('.popover-wrapper')!)
    .fromTo('opacity', 0.01, 1);

  contentAnimation
    .addElement(contentEl)
    .beforeStyles({
      'top': `${popoverCSS.top}px`,
      'left': `${popoverCSS.left}px`,
      'transform-origin': `${originY} ${originX}`
    })
    .fromTo('transform', 'scale(0.001)', 'scale(1)');

  viewportAnimation
    .addElement(baseEl.querySelector('.popover-viewport')!)
    .fromTo('opacity', 0.01, 1);

  return baseAnimation
    .addElement(baseEl)
    .easing('cubic-bezier(0.36,0.66,0.04,1)')
    .duration(300)
    .addAnimation([backdropAnimation, wrapperAnimation, contentAnimation, viewportAnimation]);
};
