Almost
I know nobody is going to believe me, but ... Irish spelling is completely regular and phonetic.
The problem is that Irish has twice as many consonant sounds as English, but only uses 18 letters of the alphabet (no j,k,q,v,w, x, y or z), so we have to use clusters of letters (like mh,bh for the "v" sound) for some sounds, and also, like in Italian, the sounds of consonants in Irish will change depending on the vowel next to them. In Irish there are about five or six like this, not just G and C as in Italian (and C and G in Irish don't change their sound.. Italian's not a good starting point for learning Irish!).
This broad/slender vowel rule is the reason why the S in Siobhán is soft ("shove-AWN"), but hard in "Saoirse" ("SEER-shuh") and "Sorcha" ("SUHR-kha"). C, meanwhile, is always hard, so Ciara is "KEER-a", not "SEER-a" or even "CHEER-a".
The three-letter group -aoi- always sounds like the vowel sound in "ear", so now you know how to pronounce "Aoife" too. Actually, if you ever do meet an Aoife, she'll be really impressed that you pronounced her name correctly... it's actually an easy name to say, but there's something about the mass of vowels that throws everyone who tries to read it.