private IEnumerator FindMatchesAndCollapse(RaycastHit2D hit2)
{
//get the second item that was part of the swipe
Item hitItem2 = hit2.collider.gameObject.GetComponent <Item>();
board.Swap(hitItem.Cell, hitItem2.Cell);
//animate swapping
hitItem.transform.TweenPosition(swapDuration, hitItem2.transform.localPosition);
hitItem2.transform.TweenPosition(swapDuration, hitItem.transform.localPosition);
yield return(new WaitForSeconds(swapDuration));
//get the matches
var hitItemMatch = board.GetMatch(hitItem.Cell);
var hitItem2Match = board.GetMatch(hitItem2.Cell);
//gather matches in one list
var totalMatches = hitItemMatch.Cells.Union(hitItem2Match.Cells).Distinct();
//if user's swap didn't create at least a min matches, undo their swap
if (totalMatches.Count() < board.minMatches)
{
hitItem.transform.TweenPosition(swapDuration, hitItem2.transform.localPosition);
hitItem2.transform.TweenPosition(swapDuration, hitItem.transform.localPosition);
yield return(new WaitForSeconds(swapDuration));
board.UndoLastSwap();
}
while (totalMatches.Count() >= board.minMatches)
{
AddScore((totalMatches.Count() - board.minMatches + 1) * matchScore);
audio.Play();
foreach (var cell in totalMatches)
{
DestroyItem(cell.Item);
}
var columns = totalMatches.Select(cell => cell.Column).Distinct();
//the order the 2 methods below get called is important!!!
//collapse the ones gone
var collapse = board.CollapseColumns(columns);
//create new ones
var newItems = GenerateNewItems(columns);
int maxDistance = Mathf.Max(collapse.MaxDistance, newItems.MaxDistance);
MoveAndAnimate(newItems.Cells, maxDistance);
MoveAndAnimate(collapse.Cells, maxDistance);
//will wait for both of the above animations
yield return(new WaitForSeconds(moveDuration * maxDistance));
totalMatches = board.GetMatches(collapse.Cells).Union(board.GetMatches(newItems.Cells)).Distinct();
}
state = State.Default;
}