1 files changed, 89 insertions, 0 deletions
diff --git a/keyboard.lua b/keyboard.lua
new file mode 100644
index 0000000..0b20570
--- /dev/null
+++ b/keyboard.lua
@@ -0,0 +1,89 @@
+--[[
+Copyright (c) 2012 Matthias Richter
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+Except as contained in this notice, the name(s) of the above copyright holders
+shall not be used in advertising or otherwise to promote the sale, use or
+other dealings in this Software without prior written authorization.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+]]--
+
+local key,code = nil, -1
+local focus, lastwidget
+
+local cycle = {
+	-- binding = {key = key, modifier1, modifier2, ...} XXX: modifiers are OR-ed!
+	prev = {key = 'tab', 'lshift', 'rshift'},
+	next = {key = 'tab'},
+}
+
+local function pressed(...)   key, code = ... end
+local function setFocus(id)   focus = id end
+local function disableFocus() focus = NO_WIDGET end
+local function clearFocus()   focus = nil end
+local function hasFocus(id)   return id == focus end
+
+local function tryGrab(id)
+	if not focus then
+		setFocus(id)
+	end
+end
+
+local function isBindingDown(bind)
+	local modifiersDown = #bind == 0 or love.keyboard.isDown(unpack(bind))
+	return key == bind.key and modifiersDown
+end
+
+local function makeCyclable(id)
+	tryGrab(id)
+	if hasFocus(id) then
+		if isBindingDown(cycle.prev) then
+			setFocus(lastwidget)
+			key = nil
+		elseif isBindingDown(cycle.next) then
+			setFocus(nil)
+			key = nil
+		end
+	end
+	lastwidget = id
+end
+
+local function beginFrame()
+	-- for future use?
+end
+
+local function endFrame()
+	key, code = nil, -1
+end
+
+return setmetatable({
+	cycle         = cycle,
+	pressed       = pressed,
+	tryGrab       = tryGrab,
+	isBindingDown = isBindingDown,
+	setFocus      = setFocus,
+	disableFocus  = disableFocus,
+	enableFocus   = clearFocus,
+	clearFocus    = clearFocus,
+	hasFocus      = hasFocus,
+	makeCyclable  = makeCyclable,
+
+	beginFrame   = beginFrame,
+	endFrame     = endFrame,
+}, {__index = function(_,k) return ({key = key, code = code})[k] end})