phpscreenshot lua-part v2

-- Version 2

term.clear()
term.setCursorPos(1,1)


-- Uses Gopher's redirect buffer api v1.2
-- http://www.computercraft.info/forums2/index.php?/topic/5130-gophers-apis-new-ggui-beta-goroutine-redirect-ctrlkeys/page__hl__gopheratl

local trueCursor={term.getCursorPos()}

local redirectBufferBase = {
    write=
      function(buffer,...)
        local cy=buffer.curY
        if cy>0 and cy<=buffer.height then
          local text=table.concat({...}," ")
          local cx=buffer.curX
          local px, py
          if buffer.isActive and not buffer.cursorBlink then
            term.native.setCursorPos(cx+buffer.scrX, cy+buffer.scrY)
          end
          for i=1,#text do
            if cx<=buffer.width then
              local curCell=buffer[cy][cx]
              local char,textColor,backgroundColor=string.char(text:byte(i)),buffer.textColor,buffer.backgroundColor
              if buffer[cy].isDirty or curCell.char~=char or curCell.textColor~=textColor or curCell.backgroundColor~=backgroundColor then
                buffer[cy][cx].char=char
                buffer[cy][cx].textColor=textColor
                buffer[cy][cx].backgroundColor=backgroundColor
                buffer[cy].isDirty=true
              end
            end
            cx=cx+1
          end
          buffer.curX=cx
          if buffer.isActive then
            buffer.drawDirty()
            if not buffer.cursorBlink then
              trueCursor={cx+buffer.scrX-1,cy+buffer.scrY-1}
              term.native.setCursorPos(unpack(trueCursor))
            end
          end
        end
      end,

    setCursorPos=
      function(buffer,x,y)
        buffer.curX=math.floor(x)
        buffer.curY=math.floor(y)
        if buffer.isActive and buffer.cursorBlink then
          term.native.setCursorPos(x+buffer.scrX-1,y+buffer.scrY-1)
          trueCursor={x+buffer.scrX-1,y+buffer.scrY-1}
        end
      end,

    getCursorPos=
      function(buffer)
        return buffer.curX,buffer.curY
      end,

    scroll=
      function(buffer,offset)
        for j=1,offset do
          local temp=table.remove(buffer,1)
          table.insert(buffer,temp)
          for i=1,#temp do
            temp[i].char=" "
            temp[i].textColor=buffer.textColor
            temp[i].backgroundColor=buffer.backgroundColor
          end
        end
        if buffer.isActive then
          term.redirect(term.native)
          buffer.blit()
          term.restore()
        end
      end,

    isColor=
      function(buffer)
        return buffer._isColor
      end,

    isColour=
      function(buffer)
        return buffer._isColor
      end,

    clear=
      function(buffer)
        for y=1,buffer.height do
          for x=1,buffer.width do
            buffer[y][x]={char=" ",textColor=buffer.textColor,backgroundColor=buffer.backgroundColor}
          end
        end
        if buffer.isActive then
          term.redirect(term.native)
          buffer.blit()
          term.restore()
        end
      end,

    clearLine=
      function(buffer)
        local line=buffer[buffer.curY]
        local fg,bg = buffer.textColor, buffer.backgroundColor
        for x=1,buffer.width do
          line[x]={char=" ",textColor=fg,backgroundColor=bg}
        end
        buffer[buffer.curY].isDirty=true
        if buffer.isActive then
          buffer.drawDirty()
        end
      end,

    setCursorBlink=
      function(buffer,onoff)
        buffer.cursorBlink=onoff
        if buffer.isActive then
          term.native.setCursorBlink(onoff)
          if onoff then
            term.native.setCursorPos(buffer.curX,buffer.curY)
            trueCursor={buffer.curX,buffer.curY}
          end
        end
      end,

    getSize=
      function(buffer)
        return buffer.width, buffer.height
      end,

    setTextColor=
      function(buffer,color)
        buffer.textColor=color
        if buffer.isActive then
          if term.native.isColor() or color==colors.black or color==colors.white then
            term.native.setTextColor(color)
          end
        end
      end,

    setTextColour=
      function(buffer,color)
        buffer.textColor=color
        if buffer.isActive then
          if term.native.isColor() or color==colors.black or color==colors.white then
            term.native.setTextColor(color)
          end
        end
      end,

    setBackgroundColor=
      function(buffer,color)
        buffer.backgroundColor=color
        if buffer.isActive then
          if term.native.isColor() or color==colors.black or color==colors.white then
        term.native.setBackgroundColor(color)
          end
        end
      end,

    setBackgroundColour=
      function(buffer,color)
        buffer.backgroundColor=color
        if buffer.isActive then
          if term.native.isColor() or color==colors.black or color==colors.white then
        term.native.setBackgroundColor(color)
          end
        end
      end,

    resize=
      function(buffer,width,height)
        if buffer.width~=width or buffer.height~=height then
          local fg, bg=buffer.textColor, buffer.backgroundColor
          if width>buffer.width then
            for y=1,buffer.height do
              for x=#buffer[y]+1,width do
                buffer[y][x]={char=" ",textColor=fg,backgroundColor=bg}
              end
            end
          end

          if height>buffer.height then
            local w=width>buffer.width and width or buffer.width
            for y=#buffer+1,height do
              local row={}
              for x=1,width do
                row[x]={char=" ",textColor=fg,backgroundColor=bg}
              end
              buffer[y]=row
            end
          end
          buffer.width=width
          buffer.height=height
        end
      end,

    blit=
      function(buffer,sx,sy,dx, dy, width,height)
        sx=sx or 1
        sy=sy or 1
        dx=dx or buffer.scrX
        dy=dy or buffer.scrY
        width=width or buffer.width
        height=height or buffer.height

        local h=sy+height>buffer.height and buffer.height-sy or height-1
        for y=0,h do
          local row=buffer[sy+y]
          local x=0
          local cell=row[sx]
          local fg,bg=cell.textColor,cell.backgroundColor
          local str=""
          local tx=x
          while true do
            str=str..cell.char
            x=x+1
            if x==width or sx+x>buffer.width then
              break
            end
            cell=row[sx+x]
            if cell.textColor~=fg or cell.backgroundColor~=bg then
              --write
              term.setCursorPos(dx+tx,dy+y)
              term.setTextColor(fg)
              term.setBackgroundColor(bg)
              term.write(str)
              str=""
              tx=x
              fg=cell.textColor
              bg=cell.backgroundColor
            end
          end
          term.setCursorPos(dx+tx,dy+y)
          term.setTextColor(fg)
          term.setBackgroundColor(bg)
          term.write(str)
        end
      end,

    drawDirty =
      function(buffer)
        term.redirect(term.native)
        for y=1,buffer.height do
          if buffer[y].isDirty then
            term.redirect(term.native)
            buffer.blit(1,y,buffer.scrX,buffer.scrY+y-1,buffer.width,buffer.height)
            term.restore()
            buffer[y].isDirty=false
          end
        end
        term.restore()
      end,

    makeActive =
      function(buffer,posX, posY)
        posX=posX or 1
        posY=posY or 1
        buffer.scrX=posX
        buffer.scrY=posY
        term.redirect(term.native)
        buffer.blit(1,1,posX,posY,buffer.width,buffer.height)
        term.setCursorPos(buffer.curX,buffer.curY)
        term.setCursorBlink(buffer.cursorBlink)
        term.setTextColor(buffer.textColor)
        term.setBackgroundColor(buffer.backgroundColor)
        buffer.isActive=true
        term.restore()
      end,

    isBuffer = true,

  }


function createRedirectBuffer(width,height,fg,bg,isColor)
   bg=bg or colors.black
   fg=fg or colors.white
   isColor=isColor~=nil and isColor or term.isColor()
   local buffer={}

   do
     local w,h=term.getSize()
     width,height=width or w,height or h
   end

   for y=1,height do
     local row={}
     for x=1,width do
       row[x]={char=" ",textColor=fg,backgroundColor=bg}
     end
     buffer[y]=row
   end
   buffer.scrX=1
   buffer.scrY=1
   buffer.width=width
   buffer.height=height
   buffer.cursorBlink=false
   buffer.textColor=fg
   buffer.backgroundColor=bg
   buffer._isColor=isColor
   buffer.curX=1
   buffer.curY=1

   local meta={}
   local function wrap(f,o)
     return function(...)
         return f(o,...)
       end
   end
   for k,v in pairs(redirectBufferBase) do
     if type(v)=="function" then
       meta[k]=wrap(v,buffer)
     else
       meta[k]=v
     end
   end
   setmetatable(buffer,{__index=meta})
   return buffer
end



local w,h = term.getSize()
local buff = createRedirectBuffer(w,h,colors.white,colors.black,true)
term.redirect(buff)
buff.makeActive(1,1)

function screenshot()
  local function c(num) --color conversion
    return string.format("%x",math.log(num)/math.log(2))
  end
  local text = ""
  local fore = ""
  local back = ""
  for y,row in ipairs(buff) do
    for x,char in ipairs(row) do
      text=text..char.char
      fore=fore..c(char.textColor)
      back=back..c(char.backgroundColor)
    end
  end
  local file = io.open("screen.txt","a")
  local url = "\nhttp://janvanrosmalen.com/ccrender/color/"
  local function add(text)
    url = url..textutils.urlEncode(tostring(text)).."/"
  end
  add(w) add(h) add(text) add(fore) add(back) add(buff.curX) add(buff.curY)
  add(c(buff.textColor)) add(c(buff.backgroundColor)) add(buff.cursorBlink)
  file:write(url.."screenshot.png")
  file:close()
end


local roll=true
function go()
  print("Press f1 to make a screenshot.")
  print("Type exit to leave screenshot mode")
  shell.run("rom/programs/shell")
  roll=false
end

local route = coroutine.create(go)
os.queueEvent("derp")
while roll do
  local evt = {os.pullEventRaw()}
  if (evt[1]=="key") and (evt[2]==keys.f1) then
    screenshot()
  end
  coroutine.resume(route,unpack(evt))
end

term.restore()
term.clear()
term.setCursorPos(1,1)
print("Left screenshot mode")