-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | HTML5 Canvas Graphics Library - forked Blank Canvas
--   
--   A Haskell port of the HTML5 Canvas API. blank-canvas works by
--   providing a web service that displays the users' Haskell commands
--   inside a browser.
@package null-canvas
@version 0.2.4

module Graphics.Blank

-- | blankCanvas is the main entry point into blank-canvas. A typical
--   invocation would be
--   
--   <pre>
--   module Main where
--   
--   import Graphics.Blank
--   
--   main = blankCanvas 3000 $ \ context -&gt; do
--           send context $ do
--                   moveTo(50,50)
--                   lineTo(200,100)
--                   lineWidth 10
--                   strokeStyle "red"
--                   stroke()
--   </pre>
blankCanvas :: Int -> (Context -> IO ()) -> IO ()
blankCanvasParams :: Int -> (Context -> IO ()) -> FilePath -> Bool -> IO ()

-- | <a>Context</a> is our abstact handle into a specific 2d-context inside
--   a browser.
data Context

-- | Sends a set of Canvas commands to the canvas. Attempts to common up as
--   many commands as possible.
send :: Context -> Canvas a -> IO a

-- | <a>events</a> gets the raw event queue for a specific event type.
events :: Context -> EventName -> IO EventQueue
data Canvas :: * -> *
arc :: (Float, Float, Float, Float, Float, Bool) -> Canvas ()
beginPath :: () -> Canvas ()
bezierCurveTo :: (Float, Float, Float, Float, Float, Float) -> Canvas ()
clearRect :: (Float, Float, Float, Float) -> Canvas ()
closePath :: () -> Canvas ()
fill :: () -> Canvas ()
fillRect :: (Float, Float, Float, Float) -> Canvas ()
fillStyle :: String -> Canvas ()
fillText :: (String, Float, Float) -> Canvas ()
font :: String -> Canvas ()
globalAlpha :: Float -> Canvas ()
lineCap :: String -> Canvas ()
lineJoin :: String -> Canvas ()
lineTo :: (Float, Float) -> Canvas ()
lineWidth :: Float -> Canvas ()
miterLimit :: Float -> Canvas ()
moveTo :: (Float, Float) -> Canvas ()
restore :: () -> Canvas ()
rotate :: Float -> Canvas ()
scale :: (Float, Float) -> Canvas ()
save :: () -> Canvas ()
stroke :: () -> Canvas ()
strokeRect :: (Float, Float, Float, Float) -> Canvas ()
strokeText :: (String, Float, Float) -> Canvas ()
strokeStyle :: String -> Canvas ()
textAlign :: String -> Canvas ()
textBaseline :: String -> Canvas ()
transform :: (Float, Float, Float, Float, Float, Float) -> Canvas ()
translate :: (Float, Float) -> Canvas ()

-- | read a specific event; wait for it if the event is not in queue.
readEvent :: EventName -> Canvas Event

-- | read a specific event; or return Nothing if the event is not in queue.
tryReadEvent :: EventName -> Canvas (Maybe Event)

-- | size of the canvas
size :: Canvas (Float, Float)

-- | Basic Event from Browser, the code is event-type specific.
data Event
Event :: Int -> Maybe (Int, Int) -> Event
jsCode :: Event -> Int
jsMouse :: Event -> Maybe (Int, Int)

-- | <a>EventName</a> mirrors event names from jquery, where 'map toLower
--   (show name)' gives the jquery event name.
data EventName
KeyPress :: EventName
KeyDown :: EventName
KeyUp :: EventName
MouseDown :: EventName
MouseEnter :: EventName
MouseMove :: EventName
MouseOut :: EventName
MouseOver :: EventName
MouseUp :: EventName

-- | EventQueue is a STM channel (<a>TChan</a>) of <a>Event</a>s.
--   Intentionally, <a>EventQueue</a> is not abstract.
type EventQueue = TChan Event
readEventQueue :: EventQueue -> IO Event
tryReadEventQueue :: EventQueue -> IO (Maybe Event)