module skeleton4

/*
	Advanced Programming.
	Skeleton for assignment 4.
	To be used in a project with the environment iTasks.
	Pieter Koopman, pieter@cs.ru.nl
*/

import StdArray
import iTasks

:: Idea	= { title :: String, desc :: Maybe Note }
:: Name	:== String

:: FullIdea = { user :: Name, number :: Int, idea :: Idea}
:: RawIdea = {data :: FullIdea}

:: NamedIdea = { name :: Name, ideas :: [Idea]}
derive class iTask NamedIdea // generic magic
derive class iTask Idea
derive class iTask FullIdea
derive class iTask RawIdea

doIdentified :: (Name -> Task x) -> Task x | iTask x
doIdentified task
	=   enterInformation "Enter your name" []
	>>= task

editIdea :: Name -> Task (Name, [Idea])
editIdea name
	=           enterInformation (name +++ " add your idea") []
	>>= \val . return (name, val)

buildOutput :: (Name, [Idea]) -> Task [RawIdea]
buildOutput (name, ideas) = return (buildIdeas name 1 ideas)

mainTask =   doIdentified editIdea
		 >>= buildOutput
		 >>= viewInformation "The result" [ViewWith filterIdeas]

buildIdeas :: Name Int [Idea] -> [RawIdea]
buildIdeas _ _ [] = []
buildIdeas usr nr [i:xs] = [{data = {user = usr, number = nr, idea = i}} : buildIdeas usr (nr+1) xs]

filterIdeas :: [RawIdea] -> [FullIdea]
filterIdeas [{data = idea=:{idea = {desc = Nothing}}}:xs] = filterIdeas xs
filterIdeas [{data = idea=:{idea = {desc = Just d}}}:xs] | size (toString d) > 10 = [idea:filterIdeas xs]
                                                         | otherwise = filterIdeas xs
filterIdeas [] = []

Start :: *World -> *World 
Start world = startEngine mainTask world