jooyunghan · September 16, 2015 16:03
diff --git a/turn_on.elm b/turn_on.elm
 import Graphics.Collage exposing (filled, rect, collage, toForm)
 import Graphics.Element exposing (image, beside, below, above, empty, Element, spacer, color)
 import Graphics.Input exposing (customButton, button)
 import Color exposing (red, yellow)
 import Signal exposing ((<~))
 import Markdown

 off_bulb = collage 30 30 [
            toForm (image 28 28 "data:image/jpeg;base64,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")
            ]
 on_bulb = collage 30 30 [
            toForm (image 28 28 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            ]

 type alias Switch = {row:Int, col:Int}
 type Click = Reset | Toggle Switch 

 click : Signal.Mailbox Click
 click = Signal.mailbox Reset

 switch_up = collage 30 30 [toForm (image 20 20 "http://www.rw-designer.com/icon-image/10454-128x128x32.png")]
 switch_hover = collage 30 30 [toForm (image 22 22 "http://www.rw-designer.com/icon-image/10455-128x128x32.png")]
 switch_down = collage 30 30 [toForm (image 20 20 "http://www.rw-designer.com/icon-image/10456-128x128x32.png")]

 switch : {row:Int, col:Int} -> Element
 switch link = customButton (Signal.message click.address (Toggle link)) switch_up switch_hover switch_down

 isOdd n = n % 2 == 1
 isEven n = n % 2 == 0

 -- model
 type alias Cell = {row:Int, col:Int, on:Bool, target:Bool}
 type alias Model = List (List Cell)

 input = {n=5, on=[(0,4), (1,0)]}

 model {n,on} = 
 List.foldl (\(row,col) model -> target (row*2+1) (col*2+1) model) (List.map (\row -> make_row row n) [1 .. 3]) on

 make_row row cols = List.map (\col -> {row=row, col=col, on=False, target=False }) [1 .. (cols*2+1)]

 model0 = model input

 toggle : Int -> Int -> Model -> Model
 toggle row col model = 
  List.map (\line -> List.map (\cell -> if .row cell == row && .col cell == col then {cell | on <- not (.on cell)} else cell) line ) model

 target : Int -> Int -> Model -> Model
 target row col model = 
  List.map (\line -> List.map (\cell -> if .row cell == row && .col cell == col then {cell | target <- True} else cell) line ) model


 app_state = {model=model, count=0}

 -- view
 view model = 
  Markdown.toElement markdown
  `above` 
  List.foldl above empty (List.map view_line model)
  `above`
  spacer 20 20
  `above`
  button (Signal.message click.address Reset) "Reset"

 view_line line = 
  List.foldl beside empty (List.map view_cell line)

 view_cell {row,col,on,target}  = 
  if | isOdd  row && isOdd col -> 
        let bulb = if on then on_bulb else off_bulb
        in if target then color yellow bulb else bulb
     | isEven  row && isEven col -> spacer 30 30
     | otherwise -> switch {row=row, col=col}

 markdown = """
 # 전구 켜기

 각 전구들 사이에 있는 스위치는 이웃한 전구 두 개를 켜거나 끌 수 있다.
 노란 테두리로 표시된 전구들만 모두 켜려면 스위치를 최소한 몇번 눌러야 할까?
 """
 -- update

 step click model = 
  case click of
    Reset -> model0
    Toggle {row,col} ->
      if | isOdd row && isEven col -> toggle row (col+1) (toggle row (col-1) model)
         | isEven row && isOdd col -> toggle (row-1) col (toggle (row+1) col model)
         | otherwise -> model

 main = view <~ Signal.foldp step model0 click.signal
	import Graphics.Collage exposing (filled, rect, collage, toForm)
	import Graphics.Element exposing (image, beside, below, above, empty, Element, spacer, color)
	import Graphics.Input exposing (customButton, button)
	import Color exposing (red, yellow)
	import Signal exposing ((<~))
	import Markdown

	off_bulb = collage 30 30 [
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	]
	on_bulb = collage 30 30 [
	toForm (image 28 28 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	]

	type alias Switch = {row:Int, col:Int}
	type Click = Reset \| Toggle Switch

	click : Signal.Mailbox Click
	click = Signal.mailbox Reset

	switch_up = collage 30 30 [toForm (image 20 20 "http://www.rw-designer.com/icon-image/10454-128x128x32.png")]
	switch_hover = collage 30 30 [toForm (image 22 22 "http://www.rw-designer.com/icon-image/10455-128x128x32.png")]
	switch_down = collage 30 30 [toForm (image 20 20 "http://www.rw-designer.com/icon-image/10456-128x128x32.png")]

	switch : {row:Int, col:Int} -> Element
	switch link = customButton (Signal.message click.address (Toggle link)) switch_up switch_hover switch_down

	isOdd n = n % 2 == 1
	isEven n = n % 2 == 0

	-- model
	type alias Cell = {row:Int, col:Int, on:Bool, target:Bool}
	type alias Model = List (List Cell)

	input = {n=5, on=[(0,4), (1,0)]}

	model {n,on} =
	List.foldl (\(row,col) model -> target (row2+1) (col2+1) model) (List.map (\row -> make_row row n) [1 .. 3]) on

	make_row row cols = List.map (\col -> {row=row, col=col, on=False, target=False }) [1 .. (cols*2+1)]

	model0 = model input

	toggle : Int -> Int -> Model -> Model
	toggle row col model =
	List.map (\line -> List.map (\cell -> if .row cell == row && .col cell == col then {cell \| on <- not (.on cell)} else cell) line ) model

	target : Int -> Int -> Model -> Model
	target row col model =
	List.map (\line -> List.map (\cell -> if .row cell == row && .col cell == col then {cell \| target <- True} else cell) line ) model


	app_state = {model=model, count=0}

	-- view
	view model =
	Markdown.toElement markdown
	`above`
	List.foldl above empty (List.map view_line model)
	`above`
	spacer 20 20
	`above`
	button (Signal.message click.address Reset) "Reset"

	view_line line =
	List.foldl beside empty (List.map view_cell line)

	view_cell {row,col,on,target} =
	if \| isOdd row && isOdd col ->
	let bulb = if on then on_bulb else off_bulb
	in if target then color yellow bulb else bulb
	\| isEven row && isEven col -> spacer 30 30
	\| otherwise -> switch {row=row, col=col}

	markdown = """
	# 전구 켜기

	각 전구들 사이에 있는 스위치는 이웃한 전구 두 개를 켜거나 끌 수 있다.
	노란 테두리로 표시된 전구들만 모두 켜려면 스위치를 최소한 몇번 눌러야 할까?
	"""
	-- update

	step click model =
	case click of
	Reset -> model0
	Toggle {row,col} ->
	if \| isOdd row && isEven col -> toggle row (col+1) (toggle row (col-1) model)
	\| isEven row && isOdd col -> toggle (row-1) col (toggle (row+1) col model)
	\| otherwise -> model

	main = view <~ Signal.foldp step model0 click.signal