Triangle distribution ifelse statement

Question

I am trying to make my own function of the triangle distribution that should return the probability, similar to the one in triangle package. The problem I have is how to incorporate the if statement of lower.tail (that should compute the lower tail) and log.p (that should compute the logarithm of the density). Is there anyone who knows how to solve this?

Thanks.

The function I have:

ptriangle3 <- function(q, a, b, c, lower.tail = T, log.p = F){
  if (!all(a <= c && c <= b && a < b)) stop("Villkoren måste uppfyllas: a <= c <= b and a < b!")
  
  ifelse(q > a & q < b,
         ifelse(q <= c,
                ((q-a)^2)/((b-a)*(c-a)),
                1-((b-q)^2)/((b-a)*(b-c))),
         ifelse(q <= a,
                0,
                1))
  
}