import { IContainerModel } from '../../../Interfaces/IContainerModel';
import { ReversePairwise } from '../../../utils/itertools';
import { Flex } from './FlexBehaviors';

/**
 * Try to push the siblings
 * @param container
 * @returns
 */
export function PushContainers(container: IContainerModel): IContainerModel {
  if (container.parent === null) {
    return container;
  }

  if (container.parent.children.length <= 1) {
    return container;
  }

  const prevIndex = container.parent.children.length - 2;
  const prev: IContainerModel = container.parent.children[prevIndex];
  const isOverlapping = prev.properties.x + prev.properties.width > container.properties.x;
  if (!isOverlapping) {
    return container;
  }

  // find hole
  let lastContainer: IContainerModel | null = null;
  let space: number = 0;

  while (space.toFixed(2) < container.properties.width.toFixed(2)) {
    // FIXME: possible infinite loop due to floating point
    // FIXME: A fix was applied using toFixed(2).
    // FIXME: A coverture check must be done to ensure that all scenarios are covered

    const it = ReversePairwise<IContainerModel>(container.parent.children.filter(child => child !== container));

    for (const { cur, next } of it) {
      const hasSpaceBetween = next.properties.x + next.properties.width < cur.properties.x;
      if (hasSpaceBetween) {
        lastContainer = cur;
        space = cur.properties.x - (next.properties.x + next.properties.width);
        break;
      }
    }

    if (lastContainer === null) {
      // no space between
      break;
    }

    const indexLastContainer = container.parent.children.indexOf(lastContainer);
    for (let i = indexLastContainer; i <= container.parent.children.length - 2; i++) {
      const sibling = container.parent.children[i];
      sibling.properties.x -= space;
    }
  }

  const hasNoSpaceBetween = lastContainer === null;
  if (hasNoSpaceBetween) {
    // test gap between the left of the parent and the first container
    space = container.parent.children[0].properties.x;
    if (space > 0) {
      for (let i = 0; i <= container.parent.children.length - 2; i++) {
        const sibling = container.parent.children[i];
        sibling.properties.x -= space;
      }
      return container;
    }
  }

  Flex(container);
  return container;
}