Function IsSmithingStyleKnown(styleItemIndex, patternIndex) from Update 4 accepts argument patternIndex, which refers to chapters. However I couldn't get it working correctly, so I'm using achievement instead. Something like:
Lua Code:
local chapters = {}
for i = 1, 14 do
--chapters[i] = IsSmithingStyleKnown(ITEMSTYLE_AREA_DWEMER, i)
local _, numCompleted = GetAchievementCriterion(1144, i)
chapters[i] = numCompleted == 1
end