transition to kernel

sys/apis/terminal.lua

@@ -1,38 +1,227 @@
 local colors = _G.colors
 local term   = _G.term
 local _gsub  = string.gsub
+local _rep = string.rep
+local _sub = string.sub
 
 local Terminal = { }
 
-function Terminal.scrollable(win, parent)
-  local w, h = win.getSize()
-  local _, ph = parent.getSize()
+-- add scrolling functions to a window
+function Terminal.scrollable(win, maxScroll)
+  local lines = { }
   local scrollPos = 0
-  local scp = win.setCursorPos
+  local oblit, oreposition = win.blit, win.reposition
 
-  win.setCursorPos = function(x, y)
-  _G._p = y
-    if y > scrollPos + ph then
-      win.scrollTo(y - ph)
+  local palette = { }
+  for n = 1, 16 do
+    palette[2 ^ (n - 1)] = _sub("0123456789abcdef", n, n)
+  end
+
+  maxScroll = maxScroll or 100
+
+  -- should only do if window is visible...
+  local function redraw()
+    local _, h = win.getSize()
+    local x, y = win.getCursorPos()
+    for i = 1, h do
+      local line = lines[i + scrollPos]
+      if line and line.dirty then
+        win.setCursorPos(1, i)
+        oblit(line.text, line.fg, line.bg)
+        line.dirty = false
+      end
     end
-    scp(x, y)
+    win.setCursorPos(x, y)
   end
 
-  win.scrollUp = function()
-    win.scrollTo(scrollPos - 1)
-  end
+  local function scrollTo(p, forceRedraw)
+    local _, h = win.getSize()
+    local ms = #lines - h            -- max scroll
+    p = math.min(math.max(p, 0), ms) -- normalize
 
-  win.scrollDown = function()
-    win.scrollTo(scrollPos + 1)
-  end
-
-  win.scrollTo = function(p)
-    p = math.min(math.max(p, 0), h - ph)
-    if p ~= scrollPos then
+    if p ~= scrollPos or forceRedraw then
       scrollPos = p
-      win.reposition(1, -scrollPos + 1, w, h)
+      for _, line in pairs(lines) do
+        line.dirty = true
+      end
     end
   end
+
+  function win.write(text)
+    local _, h = win.getSize()
+
+    scrollTo(#lines - h)
+    win.blit(tostring(text),
+      _rep(palette[win.getTextColor()], #text),
+      _rep(palette[win.getBackgroundColor()], #text))
+    local x, y = win.getCursorPos()
+    win.setCursorPos(x + #text, y)
+  end
+
+  function win.clearLine()
+    local w, h = win.getSize()
+    local _, y = win.getCursorPos()
+
+    scrollTo(#lines - h)
+    lines[y + scrollPos] = {
+      text = _rep(' ', w),
+      fg = _rep(palette[win.getTextColor()], w),
+      bg = _rep(palette[win.getBackgroundColor()], w),
+      dirty = true,
+    }
+    redraw()
+  end
+
+  function win.blit(text, fg, bg)
+    local x, y = win.getCursorPos()
+    local w, h = win.getSize()
+
+    if y > 0 and y <= h and x <= w then
+      local width = #text
+
+      -- fix ffs
+      if x < 1 then
+        text = _sub(text, 2 - x)
+        if bg then
+          bg = _sub(bg, 2 - x)
+        end
+        if bg then
+          fg = _sub(fg, 2 - x)
+        end
+        width = width + x - 1
+        x = 1
+      end
+
+      if x + width - 1 > w then
+        text = _sub(text, 1, w - x + 1)
+        if bg then
+          bg = _sub(bg, 1, w - x + 1)
+        end
+        if bg then
+          fg = _sub(fg, 1, w - x + 1)
+        end
+        width = #text
+      end
+
+      if width > 0 then
+        local function replace(sstr, pos, rstr)
+          if pos == 1 and width == w then
+            return rstr
+          elseif pos == 1 then
+            return rstr .. _sub(sstr, pos+width)
+          elseif pos + width > w then
+            return _sub(sstr, 1, pos-1) .. rstr
+          end
+          return _sub(sstr, 1, pos-1) .. rstr .. _sub(sstr, pos+width)
+        end
+
+        local line = lines[y + scrollPos]
+        line.dirty = true
+        line.text = replace(line.text, x, text, width)
+        if fg then
+          line.fg = replace(line.fg, x, fg, width)
+        end
+        if bg then
+          line.bg = replace(line.bg, x, bg, width)
+        end
+      end
+    end
+    redraw()
+  end
+
+  function win.clear()
+    local w, h = win.getSize()
+
+    local text = _rep(' ', w)
+    local fg = _rep(palette[win.getTextColor()], w)
+    local bg = _rep(palette[win.getBackgroundColor()], w)
+    lines = { }
+    for y = 1, h do
+      lines[y] = {
+        dirty = true,
+        text = text,
+        fg = fg,
+        bg = bg,
+      }
+    end
+    scrollPos = 0
+    redraw()
+  end
+
+  -- doesn't support negative scrolling...
+  function win.scroll(n)
+    local w = win.getSize()
+
+    for _ = 1, n do
+      lines[#lines + 1] = {
+        text = _rep(' ', w),
+        fg = _rep(palette[win.getTextColor()], w),
+        bg = _rep(palette[win.getBackgroundColor()], w),
+      }
+    end
+
+    while #lines > maxScroll do
+      table.remove(lines, 1)
+    end
+
+    scrollTo(maxScroll, true)
+    redraw()
+  end
+
+  function win.scrollUp()
+    scrollTo(scrollPos - 1)
+    redraw()
+  end
+
+  function win.scrollDown()
+    scrollTo(scrollPos + 1)
+    redraw()
+  end
+
+  function win.reposition(x, y, nw, nh)
+    local w, h = win.getSize()
+    local D = (nh or h) - h
+
+    if D > 0 then
+      for _ = 1, D do
+        lines[#lines + 1] = {
+          text = _rep(' ', w),
+          fg = _rep(palette[win.getTextColor()], w),
+          bg = _rep(palette[win.getBackgroundColor()], w),
+        }
+      end
+    elseif D < 0 then
+      for _ = D, -1 do
+        lines[#lines] = nil
+      end
+    end
+    return oreposition(x, y, nw, nh)
+  end
+
+  win.clear()
+end
+
+-- get windows contents
+function Terminal.getContents(win, parent)
+  local oblit, oscp = parent.blit, parent.setCursorPos
+  local lines = { }
+
+  parent.blit = function(text, fg, bg)
+    lines[#lines + 1] = {
+      text = text,
+      fg = fg,
+      bg = bg,
+    }
+  end
+  parent.setCursorPos = function() end
+
+  win.setVisible(true)
+  win.redraw()
+
+  parent.blit = oblit
+  parent.setCursorPos = oscp
+
+  return lines
 end
 
 function Terminal.toGrayscale(ct)