bedit: Added scrolling around the screen and basic event handling

halyde/apps/bedit.lua

@@ -2,6 +2,7 @@ local fs = require("filesystem")
 local shell = require("shell")
 local gpu = require("component").gpu
 local event = require("event")
+local computer = require("computer")
 
 local resX, resY = gpu.getResolution()
 local textBuffer = gpu.allocateBuffer(resX, resY - 1)
@@ -58,9 +59,15 @@ gpu.setForeground(0xFFFFFF)
 gpu.setBackground(0x000000)
 gpu.set(4, resY, "Exit")
 gpu.set(13, resY, "Save")
+
+local textOffsetX = 0
+local textOffsetY = 0
+
 while true do
+  local renderBufferFlag = false -- Flag to render the whole text buffer
   -- Handle events
-  local eventArgs = {event.pull("key_down")}
+  repeat
+    local eventArgs = {event.pull("key_down", 0.05)}
 
     if eventArgs[1] == "key_down" then
       -- Mouse events might be added later, that's why this if statement is here
@@ -68,14 +75,35 @@ while true do
         -- Special commands
         print(eventArgs[4], keyboard.keys[eventArgs[4]])
         if keyboard.keys[eventArgs[4]] == "x" then
-        break
+          goto exit
         end
       end
+
+      if keyboard.keys[eventArgs[4]] == "up" and textOffsetY > 0 then
+        textOffsetY = textOffsetY - 1
+        renderBufferFlag = true
+      end
+      if keyboard.keys[eventArgs[4]] == "down" then
+        textOffsetY = textOffsetY + 1
+        renderBufferFlag = true
+      end
+      if keyboard.keys[eventArgs[4]] == "left" and textOffsetX > 0 then
+        textOffsetX = textOffsetX - 1
+        renderBufferFlag = true
+      end
+      if keyboard.keys[eventArgs[4]] == "right" then
+        textOffsetX = textOffsetX + 1
+        renderBufferFlag = true
+      end
+    end
+  until not next(eventArgs)
+  if renderBufferFlag then
+    renderText(textOffsetX, textOffsetY)
   end
-  renderText(0, 0)
 end
 
 -- Cleanup
+::exit::
 gpu.freeBuffer(textBuffer)
 gpu.setActiveBuffer(0)
 terminal.clear()