Spreadsheet Script, match with wildcard and different cases

I am having trouble executing the Spreadsheet script below. I think there are two mistakes but I do not know how to fix. Could anyone help it to fix it?

1:Wildcard

if(original_date=='....-..-..')

2:if synteax

if(original_date=='....-..-..')
 {condition="matched"}

Detail

On the spreadsheet, there are two columns. The first columns have dates in a format as YYYY-MM-DD such as 2020-04-21. But sometimes, they have different formats such as 04/21/2020. The second columns are empty. Only when the first column cell has the "YYYY-MM-DD" format, I want to copy the cell into the second cell in the second column. *They have 10 rows.

Here is the script.

  var sheet = SpreadsheetApp.getActive().getSheetByName('Sheet1')
  for(let i=1; i<=10; i++)
  {
  original_date_range = sheet.getRange(i, 1);
  original_date = original_date_range.getValue();
  cleaned_date_range = sheet.getRange(i, 2);
  var condition = "";

  if(original_date=='....-..-..')
  {condition="matched"}

  switch(condition)
  {
  case "matched":
  cleaned_date_range.setValue(original_date);
  case "":
  cleaned_date_range.setValue("");
  break;
  }

  }