Write shell command to find long if loops within a directory of php files

I have a nested directory of files in php, some of them may have if and else conditions within them

if (condition) {
  // ~100 lines of code
}

I want to quickly find those [files/start of if or else condition] within files that have long bodies within if or else conditions. Say > 100 lines within the flower brackets

Eg:

File1:
    if (condition) {
      // >100 lines of code
    } else {
     // 50 lines of code
    }
    ...
    if (condition) {
      // 10 lines of code
    }
File2:
   if (condition) {
     // 2 lines
   }

should return the line number of the first if condition from File1 because it has 100+ lines within its opening and closing brackets. There could be nested if conditions as well