initial commit

luigi/widget.lua

@@ -0,0 +1,246 @@
+local ROOT = (...):gsub('[^.]*$', '')
+
+local Base = require(ROOT .. 'base')
+local Event = require(ROOT .. 'event')
+
+local Widget = Base:extend()
+
+Widget.isWidget = true
+
+Widget.registeredTypes = {
+    sash = ROOT .. 'widget.sash',
+    slider = ROOT .. 'widget.slider',
+    text = ROOT .. 'widget.text',
+}
+
+function Widget.create (layout, data)
+    local path = data.type and Widget.registeredTypes[data.type]
+
+    if path then
+        return require(path)(layout, data)
+    end
+
+    return Widget(layout, data)
+end
+
+function Widget:constructor (layout, data)
+    self.type = 'generic'
+    self.layout = layout
+    self.children = {}
+    self.position = { x = nil, y = nil }
+    self.dimensions = { width = nil, height = nil }
+    self:extract(data)
+    layout:addWidget(self)
+    local widget = self
+    local meta = getmetatable(self)
+    local metaIndex = meta.__index
+    function meta:__index(property)
+        local value = metaIndex[property]
+        local style = widget.layout.style
+        local theme = widget.layout.theme
+        if value ~= nil then return value end
+        value = style and style:getProperty(self, property)
+        if value ~= nil then return value end
+        return theme and theme:getProperty(self, property)
+    end
+end
+
+function Widget:extract (data)
+    function toWidget(t)
+        if t.isWidget then return t end
+        return Widget.create(self.layout, t)
+    end
+
+    for k, v in pairs(data) do
+        if type(k) == 'number' then
+            self.children[k] = toWidget(v)
+            self.children[k].parent = self
+        else
+            self[k] = v
+        end
+    end
+end
+
+function Widget:getPrevious ()
+    local siblings = self.parent.children
+    for i, widget in ipairs(siblings) do
+        if widget == self then return siblings[i - 1] end
+    end
+end
+
+function Widget:getNext ()
+    local siblings = self.parent.children
+    for i, widget in ipairs(siblings) do
+        if widget == self then return siblings[i + 1] end
+    end
+end
+
+function Widget:addChild (data)
+    local layout = self.layout
+    local child = Widget.create(layout, data)
+
+    table.insert(self.children, child)
+    child.parent = self
+    layout:addWidget(child)
+end
+
+function Widget:calculateDimension (name)
+    function clamp(value, min, max)
+        if value < min then
+            value = min
+        elseif value > max then
+            value = max
+        end
+        return value
+    end
+    if self[name] then
+        self.dimensions[name] = clamp(self[name], 0, self.layout.root[name])
+    end
+    if self.dimensions[name] then
+        return self.dimensions[name]
+    end
+    local parent = self.parent
+    if not parent then
+        return self.layout
+    end
+    local parentDimension = parent:calculateDimension(name)
+    local parentFlow = parent.flow or 'y'
+    if (parentFlow == 'y' and name == 'width') or
+        (parentFlow == 'x' and name == 'height')
+    then
+        return parentDimension
+    end
+    local claimed = 0
+    local unsized = 1
+    for i, widget in ipairs(self.parent.children) do
+        if widget ~= self then
+            if widget[name] then
+                claimed = claimed + widget:calculateDimension(name)
+                if claimed > parentDimension then
+                    claimed = parentDimension
+                end
+            else
+                unsized = unsized + 1
+            end
+        end
+    end
+    local size = (self.parent:calculateDimension(name) - claimed) / unsized
+    self.dimensions[name] = clamp(size, 0, self.layout.root[name])
+    return size
+end
+
+function Widget:calculatePosition (axis)
+    if self.position[axis] then
+        return self.position[axis]
+    end
+    local parent = self.parent
+    if not parent then
+        self.position[axis] = 0
+        return 0
+    end
+    local parentPos = parent:calculatePosition(axis)
+    local p = parentPos
+    local parentFlow = parent.flow or 'y'
+    for i, widget in ipairs(parent.children) do
+        if widget == self then
+            self.position[axis] = p
+            return p
+        end
+        if parentFlow == axis then
+            local dimension = (axis == 'x') and 'width' or 'height'
+            p = p + widget:calculateDimension(dimension)
+        end
+    end
+    self.position[axis] = 0
+    return 0
+end
+
+function Widget:getX ()
+    return self:calculatePosition('x')
+end
+
+function Widget:getY ()
+    return self:calculatePosition('y')
+end
+
+function Widget:getWidth ()
+    return self:calculateDimension('width')
+end
+
+function Widget:getHeight ()
+    return self:calculateDimension('height')
+end
+
+function Widget:setDimension (name, size)
+    local parentDimension = self.parent:calculateDimension(name)
+    local claimed = 0
+    for i, widget in ipairs(self.parent.children) do
+        if widget ~= self and widget[name] then
+            claimed = claimed + widget[name]
+        end
+    end
+    if claimed + size > parentDimension then
+        size = parentDimension - claimed
+    end
+    self[name] = size
+end
+
+function Widget:setWidth (size)
+    return self:setDimension('width', size)
+end
+
+function Widget:setHeight (size)
+    return self:setDimension('height', size)
+end
+
+function Widget:getOrigin ()
+    return self:getX(), self:getY()
+end
+
+function Widget:getExtent ()
+    local x, y = self:getX(), self:getY()
+    return x + self:getWidth(), y + self:getHeight()
+end
+
+function Widget:getRectangle (useMargin, usePadding)
+    local x1, y1 = self:getOrigin()
+    local x2, y2 = self:getExtent()
+    local function shrink(amount)
+        x1 = x1 + amount
+        y1 = y1 + amount
+        x2 = x2 - amount
+        y2 = y2 - amount
+    end
+    if useMargin then
+        shrink(self.margin or 0)
+    end
+    if usePadding then
+        shrink(self.padding or 0)
+    end
+    return x1, y1, x2, y2
+end
+
+function Widget:isAt (x, y)
+    local x1, y1, x2, y2 = self:getRectangle()
+    return (x1 < x) and (x2 > x) and (y1 < y) and (y2 > y)
+end
+
+function Widget:getAncestors (includeSelf)
+    local instance = includeSelf and self or self.parent
+    return function()
+        local widget = instance
+        if not widget then return end
+        instance = widget.parent
+        return widget
+    end
+end
+
+function Widget:update ()
+    self.layout:update()
+end
+
+-- event binders
+
+Event.injectBinders(Widget)
+
+return Widget