refactor parallel code

openos/apis/tty.lua

@@ -0,0 +1,23 @@
+local colors = _G.colors
+local term   = _G.term
+
+local w, h = term.getSize()
+
+local cmap = {
+  [ 0xCC2200 ] = colors.red,
+  [ 0x44CC00 ] = colors.lime,
+  [ 0xB0B00F ] = colors.yellow,
+  [ 0xFFFFFF ] = colors.white,
+}
+
+return {
+  gpu = function()
+    return {
+      setForeground = function(c) term.setTextColor(cmap[c]) end,
+    }
+  end,
+  getViewport = term.getSize,
+  window = {
+    width = w, height = h,
+  }
+}