Implement text-progress bar

gfx/textprogress.lua

@@ -0,0 +1,29 @@
+local Util = require("util")
+local Text = require("gfx.text")
+local TextProgress = Text:new()
+
+function TextProgress:getProgress()
+  return math.max(0, math.min(self.progress or 0, 1))
+end
+
+function TextProgress:setProgress(progress)
+  self.progress = progress
+end
+
+function TextProgress:draw()
+  getmetatable(getmetatable(self)).draw(self)
+  local width = self:getWidth()
+  local activePart = math.ceil(width * self:getProgress())
+
+  local fg = 0
+  local bg = 0
+
+  for i=self:getWidth(),1,-1 do
+    fg = bit.blshift(fg, 4) + (i > activePart and self:getFgColor() or self:getBgColor())
+    bg = bit.blshift(fg, 4) + (i > activePart and self:getBgColor() or self:getFgColor())
+  end
+
+  self:_getWindow().blit(self:getText(), Util.valueToHex(fg), Util.valueToHex(bg))
+end
+
+return TextProgress

util/init.lua

@@ -0,0 +1,13 @@
+local Util = {}
+
+function Util.valueToHex(value)
+  local collect = {}
+  while value > 0 do
+    local idx = value % 16
+    table.insert(collect, 1, ("0123456789ABCDEF"):sub(idx, idx))
+    value = bit.brshift(value, 4)
+  end
+  return table.concat(collect)
+end
+
+return Util