"The pkg-config package poppler-glib version >=0.12.4 is required but it
could not be found."
I don't know how to fix this, as "poppler-glib" is not a package
(and not a dependency).
It's not a Haskell package, but a C package. pkg-config is a mostly portable mechanism C programs can use to find out the location of a C library package, and how to link against that package. One thing it can *not* help you with, though, is figuring out how to install said library on your platform.
(And all I can recommend is, don't try to use MacPorts to install poppler, because you'll end up with a conflicting version of iconv. Fink or Homebrew may work better.)