gedit v0.4a (computercraft lua)

--[[ gedit
advanced editor with undo, page views with word wrap, keyboard shortcuts, and
advanced printing functions (coming soon)

based on edit by dan200+cloudy, enhancements by GopherAtl

Do whatever you want, unless you want to take credit, in which case screw you, jerk.

--]]
-- Get file to edit
local tArgs = { ... }
if #tArgs == 0 then
    print( "Usage: edit <path>" )
    return
end

-- Error checking
local sPath = shell.resolve( tArgs[1] )
local bReadOnly = fs.isReadOnly( sPath )
if fs.exists( sPath ) and fs.isDir( sPath ) then
    print( "Cannot edit a directory." )
    return
end

local x,y = 1,1
local w,h = term.getSize()
local scrollX, scrollY = 0,0

local tLinesRaw = {} --raw lines - end in implied \ns
local tLinesDrawn = {} --modified version for current draw view, with addl. metadata

local bRunning = true
local bChanged = false
local tViewModes = {"code","document","page"}
local nViewMode = 0

--undo related
local tUndo={}
local tRedo={}
local hChangeTimer=0
local sLastChangeType=""

--conveinence guys
local function fTrue() return true end
local function fFalse() return false end
local function fNil() end
local function hasChanged() return bChanged end

-- Menus and other fierce creatures
local nMenuItem = 1
local onConfirm=fNil
local sMenuTitle=""

local tMenuStack = {}

--confirmation menu
local tConfirm = {
  {hotkey="n", sLabel="No", fConfirm=fFalse, onSelect=fNil},
  {hotkey="y", sLabel="Yes", fConfirm=fFalse, onSelect=fNil},
}

--forms
local tActiveForm=nil
local nSelectedField=1
local nFieldCursorX=1
local nFieldCursorY=1


--printer settings
local tFormPrintSettings = {
    { sLabel="Tab Size", type="number", value=2,
      x=2, y=3, nLabelWidth=10, nFieldWidth=3 },
    { sLabel="Indent", type="number", value=0,
      x=2, y=4, nLabelWidth=10, nFieldWidth=3 },
    { sLabel="Copies", type="number", value=1,
      x=2, y=5, nLabelWidth=10, nFieldWidth=3 },
    { sLabel="Color", type="boolean", value=false,
      x=2, y=6, nLabelWidth=10, nFieldWidth=3 },
    width=31,height=17,
    x=(w-31)/2, y=(h-17)/2,

  }

local tPrintSettings={tabSize=2,indent=0,numCopies=1,color=true}

local sStatus = "Press Ctrl to access menu"


local function onChange(sType,sChar,x,y)
  bChanged=true
  if sType==sLastChangeType then
    --append to current change
    if sType=="backspace" then --backspace deletes from right to left
      tUndo[#tUndo].sText=sChar..tUndo[#tUndo].sText
    else
      tUndo[#tUndo].sText=tUndo[#tUndo].sText..sChar
    end
    tUndo[#tUndo].nCount=tUndo[#tUndo].nCount+1
  else
    --start new change
    tUndo[#tUndo+1]={sType=sType,sText=sChar,nCount=1,x=x,y=y}
  end
  --any changes obliterate any redo hist..., er, future.
  tRedo={}
  sLastChangeType=sType
  hChangeTimer=os.startTimer(1)
end

local function closeChange()
  hChangeTimer=0
  sLastChangeType=""
end



local function load(_sPath)
    tLinesRaw = {}
    if fs.exists( _sPath ) then
        local file = io.open( _sPath, "r" )
        local sLine = file:read()
        while sLine do
      table.insert( tLinesRaw, sLine )
            sLine = file:read()
        end
        file:close()
    end

  if #tLinesRaw == 0 then
    table.insert( tLinesRaw, "" )
    end
end

local function save( _sPath )
    -- Create intervening folder
    local sDir = sPath:sub(1, sPath:len() - fs.getName(sPath):len() )
    if not fs.exists( sDir ) then
        fs.makeDir( sDir )
    end

    -- Save
    local file = nil
    local function innerSave()
        file = fs.open( _sPath, "w" )
        if file then
            for n, sLine in ipairs( tLinesRaw ) do
                file.write( sLine .. "\n" )
            end
        else
            error( "Failed to open ".._sPath )
        end
    end

    local ok = pcall( innerSave )
    if file then
        file.close()
    end
    return ok
end


--======= Drawing functions =======--

function getWrapCol(str,w)
  --start at w and work back
  for i=w,1,-1 do
    if string.sub(str,i,i)==' ' or string.sub(str,i,i)=='\t' then
      return i
    end
  end
  --whole thing had no breaks, so interrupt word :(
  return w
end


function getStrippedLine(rawLine,viewMode)
  local outStr=""
  local i=1
  local wrapW=viewMode==3 and 25 or w
  while i<=#rawLine do
    local ch=string.sub(rawLine,i,i)
    if viewMode==3 and ch=="%" then
      i=i+1
      ch=string.sub(rawLine,i,i)
      if ch=="%" or ch=="" then
        outStr=outStr..ch
      elseif ch=="<" then
        outStr=""
      end
    elseif ch=="\t" then
      local spaces=tFormPrintSettings[1].value-#outStr%tFormPrintSettings[1].value
      outStr=outStr..string.rep(" ",spaces)
    elseif ch=="\n" then
      if i>1 then
        error("somehow a \n got left in a line, should've been split before it got to getStrippedLine!")
      end
      outStr=string.rep(" ",tFormPrintSettings[2].value)
    else
      outStr=outStr..ch
    end

    i=i+1
  end
  local outLines={}
  local offset=0
  local offScr=0
  local i=1
  if viewMode>1 and #outStr>wrapW then
    local nSub=0 --subline number
    while #outStr>wrapW do
      wrapPos=getWrapCol(outStr,wrapW)
      outLines[i]={s=string.sub(outStr,1,wrapPos).."",offsetRaw=offset, offsetScr=offScr}
      offset=offset+wrapPos
      offScr=offScr+#outLines[i].s
      i=i+1
      outStr=string.sub(outStr,wrapPos+1)..""
    end
  end
  outLines[i]={s=outStr,offsetRaw=offset, offsetScr=offScr}
  return outLines
end


function scrPosToRaw(x,y,view)
  if view==nil then view=nVieWMode end
  local rawY=tLinesDrawn[y].raw
  local sLine = tLinesRaw[rawY]
  local rawX=scrColToIndex(sLine,tLinesDrawn[y].offsetScr+x,view)
  return rawX,rawY
end

function scrColToIndex(rawLine,col,viewMode)
  if viewMode==nil then viewMode=nViewMode end
  local index, curCol=1,1
  while curCol<col and index<=#rawLine do
    local ch=string.sub(rawLine,index,index)
    if ch=="\n" then
      curCol=curCol+tPrintSettings.indent
    elseif ch=="\t" then
      curCol=curCol-(curCol-1)%tPrintSettings.tabSize + tPrintSettings.tabSize
      index=index+1
    elseif viewMode==3 and ch=="%" then
      if #rawLine>index and string.sub(rawLine,index+1,index+1)=="%" then
        curCol=curCol+1
      end
      index=index+2
    else
      index=index+1
      curCol=curCol+1
    end
  end

  if viewMode==3 then
    while index<=#rawLine and string.sub(rawLine,index,index)=="%" do
      if index<#rawLine and string.sub(rawLine,index+1,index+1)=="%" then
        break
      end
      index=index+2
    end
  end
  return index
end

function rawToScrPos(rawX,rawY,viewMode)
  if viewMode==nil then viewMode=nViewMode end
  local sLine=tLinesRaw[rawY]
  local x,y=0,1
  --get the initial y for the line rawY
  while rawY>tLinesDrawn[y].raw do
    y=y+1
  end
  --zero in on actual line
  local offset=0
  while y<#tLinesDrawn and tLinesDrawn[y+1].raw==rawY and tLinesDrawn[y+1].offsetRaw<rawX do
    offset=tLinesDrawn[y+1].offsetRaw
    y=y+1
  end
  --loop through raw to find this actual offset
  while offset<rawX do
    local ch=string.sub(sLine,offset,offset)
    if ch=="%" and viewMode==3 then
      if #sLine>offset and string.sub(sLine,offset+1,offset+1)=="%" then
        x=x+1
      end
      offset=offset+2
    elseif ch=="\n" then
      x=x+tPrintSettings.indent
      offset=offset+1
    elseif ch=="\t" then
      x=x-(x-1)%tPrintSettings.tabSize+tPrintSettings.tabSize
      offset=offset+1
    else
      x=x+1
      offset=offset+1
    end
  end
  return x,y
end

local function redrawText()
    for y=1,h-1 do
        term.setCursorPos( 1 - scrollX, y )
        term.clearLine()

        local sLine = tLinesDrawn[ y + scrollY ]
        if sLine ~= nil then
            term.write( sLine.s )
        end
    end
    term.setCursorPos( x - scrollX, y - scrollY )
end

local function rebuildText()
  tLinesDrawn={}

  local iDrawn=1
  for i,sLine in ipairs(tLinesRaw) do
    --if it fits, just copy it
    local stripped=getStrippedLine(sLine,nViewMode)

    for j=1,#stripped do
      tLinesDrawn[iDrawn]=stripped[j]
      tLinesDrawn[iDrawn].raw=i
      iDrawn=iDrawn+1
    end
  end
  redrawText()
end


local function updateFormCursorPos()
  local tField=tActiveForm[nSelectedField]
  if tField.type=="number" or tField.type=="boolean" then
    nFieldCursorX=tField.nFieldWidth
    nFieldCursorY=1
  else
    nFieldCursorX=#tField.value
  end
end

local function redrawForm(all)
   --draw the frame
   local x,y=tActiveForm.x,tActiveForm.y
   local width,height=tActiveForm.width,tActiveForm.height
   if all then
     --error("redrawing all,"..x..","..y..")
     term.setCursorPos(x,y)
     term.write("+"..string.rep("-",width-2).."+")
     for i=1,height-2 do
       term.setCursorPos(x,y+i)
       term.write("|"..string.rep(" ",width-2).."|")
     end
     term.setCursorPos(x,y+2)
     term.write("+"..string.rep("-",width-2).."+")
     term.setCursorPos(x,y+height-1)
     term.write("+"..string.rep("-",width-2).."+")
     term.setCursorPos(x+6,y+1)
     term.write("Print preferences")
   end

   --fields and values
   for i=1,#tActiveForm do
     local field=tActiveForm[i]
     term.setCursorPos(x+field.x,y+field.y)
     term.write(field.sLabel)
     term.setCursorPos(x+field.x+field.nLabelWidth,y+field.y)
     --generate value string
     local fieldStr=""
     if field.type=="number" then
       fieldStr=tostring(field.value)
       fieldStr=string.rep(" ",field.nFieldWidth-#fieldStr)..fieldStr
     elseif field.type=="boolean" then
       fieldStr=field.value and "Yes" or "No"
       fieldStr=fieldStr..string.rep(" ",field.nFieldWidth-#fieldStr)
     else
       fieldStr=field.value..string.rep(" ",field.nFieldWidth-#field.value)
     end

     if nSelectedField==i then
       fieldStr="["..fieldStr.."]"
     else
       fieldStr=" "..fieldStr.." "
     end
     term.write(fieldStr)
   end

   --set the cursor position into the active field
   local tField=tActiveForm[nSelectedField]
   term.setCursorPos(
        x+tField.x+tField.nLabelWidth+1+nFieldCursorX,
        y+tField.y+nFieldCursorY-1)

end

local function redrawLine(_nY)
    local sLine = tLinesDrawn[_nY].s
    term.setCursorPos( 1 - scrollX, _nY - scrollY )
    term.clearLine()
    term.write( sLine )
    term.setCursorPos( x - scrollX, _nY - scrollY )
end

local function redrawRawLine(rawY)
  local sLine=tLinesRaw[rawY]
  local startLine
  for i=1,#tLinesDrawn do
    if tLinesDrawn[i].raw==rawY then
      startLine=i
      break
    end
  end
  local endLine=startLine
  while endLine<#tLinesDrawn and tLinesDrawn[endLine+1].raw==rawY do
    endLine=endLine+1
  end

  local newLines=getStrippedLine(sLine,nViewMode)
  for i=1,#newLines do
    if tLinesDrawn[startLine+i-1]==nil or tLinesDrawn[startLine+i-1].raw~=rawY then
      table.insert(tLinesDrawn,startLine+i-1,newLines[i])
    else
      tLinesDrawn[startLine+i-1]=newLines[i]
    end
    tLinesDrawn[startLine+i-1].raw=rawY
  end
  if endLine-startLine+1 == #newLines then
    for j=startLine,endLine do
      redrawLine(j)
    end
  else
    redrawText()
  end
end

local function redrawMenu()
  local prevX,prevY=term.getCursorPos()
  term.setCursorPos( 1, h )
    term.clearLine()
    local sLeft, sRight
    if #tMenuStack>0 then
    local tActiveMenu=tMenuStack[#tMenuStack]
    local sMenu = sMenuTitle
        for n,tItem in ipairs( tActiveMenu ) do
            if n == nMenuItem then
        sMenu = sMenu.."["..tItem.sLabel.."]"
            else
        sMenu = sMenu.." "..tItem.sLabel.." "
            end
        end
        sLeft = sMenu
  else
        sLeft = sStatus
    end
    sRight = "Ln "..y

    -- Left goes last so that it can overwrite the line numbers.
    if sRight then
        term.setCursorPos( w-sRight:len()+1, h )
        term.write(sRight)
    end
    if sLeft then
        term.setCursorPos( 1, h )
        term.write(sLeft)
    end

    -- Cursor highlights selection
    term.setCursorPos( prevX,prevY)
end


local function menuStub()
  sStatus = "feature not implemented"
end

local function confirmAndDo(item)
  if not item.fConfirm() then
    item.onSelect()
    return true
  else
    tMenuStack[#tMenuStack+1]=tConfirm
    nMenuItem=1
    tConfirm[2].onSelect=item.onSelect
    sMenuTitle=item.sConfirm
    return false
  end
end

local function doMenuItem( _n )
  local tMenu=tMenuStack[#tMenuStack]
  local bClosed=true
  if type(tMenu[_n].onSelect)=="table" then
    --open submenu
    tMenuStack[#tMenuStack+1]=tMenu[_n].onSelect
    bClosed=false
    nMenuItem=1
  else
    bClosed=confirmAndDo(tMenu[_n])
  end
    if #tMenuStack>0 and bClosed then
        tMenuStack = {}
        term.setCursorBlink( true )
    end
    redrawMenu()
end

local function setCursor( x, y )
    local screenX = x - scrollX
    local screenY = y - scrollY

    local bRedraw = false
    if screenX < 1 then
        scrollX = x - 1
        screenX = 1
        bRedraw = true
    elseif screenX > w then
        scrollX = x - w
        screenX = w
        bRedraw = true
    end

    if screenY < 1 then
        scrollY = y - 1
        screenY = 1
        bRedraw = true
    elseif screenY > h-1 then
        scrollY = y - (h-1)
        screenY = h-1
        bRedraw = true
    end

    if bRedraw then
        redrawText()
    end
    term.setCursorPos( screenX, screenY )

    -- Statusbar now pertains to menu, it would probably be safe to redraw the menu on every key event.
    redrawMenu()
end

local function switchViewMode(nNewMode)
  --convert current cursor pos to raw
  local rawY=tLinesDrawn[y].raw
  local sLine = tLinesRaw[rawY]
  local rawX=scrColToIndex(sLine,tLinesDrawn[y].offsetScr+x,nViewMode)

  if nNewMode==nViewMode then
    return
  end
  nViewMode=nNewMode
  rebuildText()
  --convert raw position back to screen
  x,y=rawToScrPos(rawX,rawY,nViewMode)
  setCursor(x,y)
end



-- modification functions - called on keystroke, also by undo/redo
local function backspace()
  local rawY=tLinesDrawn[y].raw
  local sLine = tLinesRaw[rawY]
  local rawX=scrColToIndex(sLine,tLinesDrawn[y].offsetScr+x,nViewMode)

  local ch=""
  if rawX > 1 then
    -- Remove character
    local sLine = tLinesRaw[rawY]
    local prevRawX=scrColToIndex(sLine,tLinesDrawn[y].offsetScr+x-1,nViewMode)
    ch=string.sub(sLine,prevRawX,rawX-1)
    tLinesRaw[rawY] = string.sub(sLine,1,prevRawX-1) .. string.sub(sLine,rawX)
    redrawRawLine(rawY)

    rawX = prevRawX
    x,y=rawToScrPos(rawX,rawY,nViewMode)
    setCursor( x, y )
  elseif y > 1 then
    -- Remove newline
    local sPrevLen = string.len( tLinesRaw[rawY-1] )
    tLinesRaw[rawY-1] = tLinesRaw[rawY-1] .. tLinesRaw[rawY]
    table.remove( tLinesRaw, rawY )
    rebuildText()
    redrawText()
    ch="\n"
    rawX = sPrevLen + 1
    rawY = rawY - 1
    x,y=rawToScrPos(rawX,rawY,nViewMode)
    setCursor( x, y )
  end
  return ch
end

local function delete()
  local rawY=tLinesDrawn[y].raw
  local sLine = tLinesRaw[rawY]
  local rawX=scrColToIndex(sLine,tLinesDrawn[y].offsetScr+x,nViewMode)
  local ch=""
  if  rawX < string.len( tLinesRaw[rawY] ) + 1 then
    local sLine = tLinesRaw[rawY]
    ch=string.sub(sLine,rawX,rawY)
    tLinesRaw[rawY] = string.sub(sLine,1,x-1) .. string.sub(sLine,x+1)
    redrawRawLine(rawY)
  elseif y<#tLinesRaw then
    tLinesRaw[rawY] = tLinesRaw[rawY] .. tLinesRaw[rawY+1]
    ch="\n"
    table.remove( tLinesRaw, rawY+1 )
    rebuildText()
  end
  return ch
end

local function insert(text, bRight)
  local rawY=tLinesDrawn[y].raw
  local sLine = tLinesRaw[rawY]
  local rawX=scrColToIndex(sLine,tLinesDrawn[y].offsetScr+x,nViewMode)
  tLinesRaw[rawY] = string.sub(sLine,1,rawX-1) .. text .. string.sub(sLine,rawX)
  sLine=tLinesRaw[rawY]
  local i=0

  --rebuild and draw raw line
  redrawRawLine(rawY)
  --update cursor
  if not bRight then
    rawX=rawX+ string.len( text )
    x,y=rawToScrPos(rawX,rawY,nViewMode)
  end
  setCursor( x, y )
end


local function newline()
  -- Newline
  local rawY=tLinesDrawn[y].raw
  local sLine = tLinesRaw[rawY]
  local rawX=scrColToIndex(sLine,tLinesDrawn[y].offsetScr+x,nViewMode)
  local _,spaces=string.find(sLine,"^[ ]+")
  if not spaces then
    spaces=0
  end
  tLinesRaw[rawY] = string.sub(sLine,1,rawX-1)
  table.insert( tLinesRaw, rawY+1, string.rep(' ',spaces)..string.sub(sLine,rawX) )
  rebuildText()

  rawX = 1
  rawY = rawY + 1
  x,y=rawToScrPos(rawX,rawY,nViewMode)
  setCursor( x, y )
end

--File menu
function fileSave()
  if bReadOnly then
    sStatus = "Access denied"
  else
    local ok, err = save( sPath )
    if ok then
      sStatus="Saved to "..sPath
      bChanged=false
    else
      sStatus="Error saving to "..sPath
    end
  end
  redrawMenu()
end

fileSaveAs=menuStub

function fileRevert()
  if bChanged then
    load( sPath )
    redrawText()
    sStatus="Reverted to last saved version"
    bChanged=false
  else
    sStatus="No changes to revert"
  end
end

fileOpen=menuStub

--print menu
function printPrint()
  local sPrinterSide = nil
  for n,sSide in ipairs(rs.getSides()) do
    if peripheral.isPresent(sSide) and peripheral.getType(sSide) == "printer" then
      sPrinterSide = sSide
      break
    end
  end

  if not sPrinterSide then
    sStatus = "No printer attached"
    return
  end

  local nPage = 0
  local sName = fs.getName( sPath )
  local printer = peripheral.wrap(sPrinterSide)
  if printer.getInkLevel() < 1 then
    sStatus = "Printer out of ink"
    return
  elseif printer.getPaperLevel() < 1 then
    sStatus = "Printer out of paper"
    return
  end

  local terminal = {
    getCursorPos = printer.getCursorPos,
    setCursorPos = printer.setCursorPos,
    getSize = printer.getPageSize,
    write = printer.write,
  }
  terminal.scroll = function()
    if nPage == 1 then
      printer.setPageTitle( sName.." (page "..nPage..")" )
    end

    while not printer.newPage() do
      if printer.getInkLevel() < 1 then
        sStatus = "Printer out of ink, please refill"
      elseif printer.getPaperLevel() < 1 then
        sStatus = "Printer out of paper, please refill"
      else
        sStatus = "Printer output tray full, please empty"
      end

      term.restore()
      redrawMenu()
      term.redirect( terminal )

      local timer = os.startTimer(0.5)
      sleep(0.5)
    end

    nPage = nPage + 1
    if nPage == 1 then
      printer.setPageTitle( sName )
    else
      printer.setPageTitle( sName.." (page "..nPage..")" )
    end
  end

  bMenu = false
  term.redirect( terminal )
  local ok, error = pcall( function()
    term.scroll()
    for n, sLine in ipairs( tLinesRaw ) do
      print( sLine )
    end
  end )
  term.restore()
  if not ok then
    print( error )
  end

  while not printer.endPage() do
    sStatus = "Printer output tray full, please empty"
    redrawMenu()
    sleep( 0.5 )
  end
  bMenu = true

  if nPage > 1 then
    sStatus = "Printed "..nPage.." Pages"
  else
    sStatus = "Printed 1 Page"
  end
  redrawMenu()
end

printPreview=menuStub

local function printSettings()
  tActiveForm=tFormPrintSettings
  nSelectedField=1
  updateFormCursorPos()
  redrawForm(true)
end


--other main
function _exit()
  bRunning = false
end

function _undo()
  if #tUndo==0 then
    sStatus="Nothing to undo!"
  else
    bChanged=false
    --grab it and move to the redo stack
    local tUndoing=tUndo[#tUndo]
    tUndo[#tUndo]=nil
    tRedo[#tRedo+1]=tUndoing
    --set cursor where it was
    x,y=rawToScrPos(tUndoing.x,tUndoing.y)
    --now undo it
    if tUndoing.sType=="char" then
      --move cursor to the end of the inserted text
      x=x+#tUndoing.sText
      --undo with a backspace!
      for i=1,#tUndoing.sText do
        backspace()
      end
    elseif tUndoing.sType=="backspace" then
      x=x-#tUndoing.sText
      --insert the text that was removed
      insert(tUndoing.sText)
    elseif tUndoing.sType=="delete" then
      --insert the snipped text to the right
      insert(tUndoing.sText,true)
    elseif tUndoing.sType=="backspaceNewline" then
      newline()
    elseif tUndoing.sType=="deleteNewline" then
      newline()
    elseif tUndoing.sType=="newline" then
      x=1
      y=y+1
      backspace()
    end

    sStatus=""
  end
end

function _redo()
  if #tRedo==0 then
    sStatus="Nothing to redo!"
  else
    bChanged=false
    --grab it and move to the redo stack
    local tRedoing=tRedo[#tRedo]
    tRedo[#tRedo]=nil
    tUndo[#tUndo+1]=tRedoing
    --set cursor where it was
    x,y=rawToScrPos(tRedoing.x,tRedoing.y)
    --now undo it
    if tRedoing.sType=="char" then
      insert(tRedoing.sText)
    elseif tRedoing.sType=="backspace" then
      --undo with a backspace!
      for i=1,tRedoing.nCount do
        backspace()
      end
    elseif tRedoing.sType=="delete" then
      --undo with a backspace!
      for i=1,tRedoing.nCount do
        delete()
      end
    elseif tRedoing.sType=="backspaceNewline" then
      y=y+1
      x=1
      backspace()
    elseif tRedoing.sType=="deleteNewline" then
      delete()
    elseif tRedoing.sType=="newline" then
      newline()
    end

    sStatus=""
  end
end

local sConfirmDiscard="Discard unsaved changes? "

local tMenuItems = {
  {hotkey="f", sLabel="File", fConfirm=fFalse,
      onSelect={
        {hotkey="s",sLabel="(S)ave", fConfirm=fFalse,onSelect=fileSave},
        {hotkey="a",sLabel="Save (A)s", fConfirm=fFalse,onSelect=fileSaveAs},
        {hotkey="r",sLabel="(R)evert",fConfirm=hasChanged,sConfirm=sConfirmDiscard,onSelect=fileRevert},
        {hotkey="o",sLabel="(O)pen", fConfirm=hasChanged,sConfirm=sConfirmDiscard,onSelect=fileOpen},
        {hotkey="x", sLabel="E(x)it",fConfirm=hasChanged,sConfirm=sConfirmDiscard,onSelect=_exit},
      },
    },
  {hotkey="e", sLabel="Edit", fConfirm=false,
      onSelect={
        {hotkey="z", sLabel="Undo(Z)",fConfirm=fFalse,onSelect=_undo},
        {hotkey="y", sLabel="Redo(Y)",fConfirm=fFalse,onSelect=_redo},
      },
    },
  {hotkey="v", sLabel="View", fConfirm=false,
      onSelect={
        {hotkey="c", sLabel="Code view",fConfirm=fFalse,onSelect=function() switchViewMode(1) end},
        {hotkey="d", sLabel="Document view",fConfirm=fFalse,onSelect=function() switchViewMode(2) end},
        {hotkey="p", sLabel="Page view",fConfirm=fFalse,onSelect=function() switchViewMode(3) end},
      },
    },
  {hotkey="p", sLabel="Print", fConfirm=fFalse,
      onSelect={
        {hotkey="p",sLabel="(P)rint",fConfirm=fFalse,onSelect=printPrint},
        {hotkey="r",sLabel="P(r)eview...",fConfirm=fFalse,onSelect=printPreview},
        {hotkey="s",sLabel="(S)ettings...",fConfirm=fFalse,onSelect=printSettings},
      }
    },
}

--table of ctrl-key events handled in the doc view - also handled in menu while not in a form?
local tDocCtrlKeys={
    one={fConfirm=fFalse,onSelect=function() switchViewMode(1) end},
    two={fConfirm=fFalse,onSelect=function() switchViewMode(2) end},
    three={fConfirm=fFalse,onSelect=function() switchViewMode(3) end},

    r={fConfirm=hasChanged,sConfirm=sConfirmDiscard,onSelect=fileRevert},
    x={fConfirm=hasChanged,sConfirm=sConfirmDiscard,onSelect=_exit},
    s={fConfirm=fFalse,onSelect=fileSave},
    a={fConfirm=fFalse,onSelect=fileSaveAs},
    p={fConfirm=fFales,onSelect=printPrint},

    z={fConfirm=fFalse,onSelect=_undo},
    y={fConfirm=fFalse,onSelect=_redo},

}

function docInputHandler(sEvent,param)
  if sEvent == "key" then
    if param == 200 then --up
      closeChange()
      -- Up
      if y > 1 then
        -- Move cursor up
        y = y - 1
        x = math.min( x, string.len( tLinesDrawn[y].s ) + 1 )
        setCursor( x, y )
      end
    elseif param == 208 then --down
      closeChange()
      -- Down
      -- Move cursor down
      if y < #tLinesDrawn then
        y = y + 1
        x = math.min( x, string.len( tLinesDrawn[y].s ) + 1 )
        setCursor( x, y )
      end
    elseif param == 15 then --tab
      -- Tab
      --[[local sLine = tLinesRaw[y]

      -- Indent line
      -- IN CASE OF INSERT TAB IN PLACE:
      -- tLinesRaw[y] = string.sub(sLine,1,x-1) .. "  " .. string.sub(sLine,x)
      local nSpaces=2-x%2
      local sSpaces=string.rep(" ",nSpaces)
      local px,py=x,y
      tLinesRaw[y]=sSpaces..tLinesRaw[y]
      x = x+nSpaces
      setCursor( x, y )
      redrawLine(y)
      --]]
      local px,py=scrPosToRaw(x,y)
      insert("\t")
      onChange("char","\t",px,py)
    elseif param == 201 then --pageUp
      closeChange()
      -- Page Up
      -- Move up a page
      local sx,sy=term.getSize()
      y=y-sy-1
      if y<1 then y=1 end
      x = math.min( x, string.len( tLinesDrawn[y].s ) + 1 )
      setCursor( x, y )
    elseif param == 209 then --pageDown
      closeChange()
      -- Page Down
      -- Move down a page
      local sx,sy=term.getSize()
      if y<#tLinesDrawn-sy-1 then
        y = y+sy-1
      else
        y = #tLinesDrawn
      end
      x = math.min( x, string.len( tLinesDrawn[y].s ) + 1 )
      setCursor( x, y )
    elseif param == 199 then --home
      closeChange()
      -- Home
      -- [TODO] respect indentation here
      -- Move cursor to the beginning
      x=1
      setCursor(x,y)
    elseif param == 207 then --end
      closeChange()
      -- End
      -- Move cursor to the end
      x = string.len( tLinesDrawn[y].s ) + 1
      setCursor(x,y)
    elseif param == 203 then --left
      closeChange()
      -- Left
      if x > 1 then
        -- Move cursor left
        x = x - 1
      elseif x==1 and y>1 then
        x = string.len( tLinesDrawn[y-1].s ) + 1
        y = y - 1
      end
      setCursor( x, y )
    elseif param == 205 then --right
      closeChange()
      -- Right
      if x < string.len( tLinesDrawn[y].s ) + 1 then
        -- Move cursor right
        x = x + 1
      elseif x==string.len( tLinesDrawn[y].s ) + 1 and y<#tLinesDrawn then
        x = 1
        y = y + 1
      end
      setCursor( x, y )
    elseif param == 211 then --delete
      -- Delete
      local px,py=scrPosToRaw(x,y)
      local ch=delete()
      if ch=="\n" then
        closeChange()
        onChange("deleteNewline",ch,px,py)
        closeChange()
      else
        onChange("delete",ch,px,py)
      end
    elseif param == 14 then --backspace
      -- Backspace
      local px,py=scrPosToRaw(x,y)
      local ch=backspace()
      if ch=="\n" then
        closeChange()
        --NOTE this special case uses x,y, not px,py!
        onChange("backspaceNewline","",x,y)
        closeChange()
      else
        onChange("backspace",ch,px,py)
      end
    elseif param == 28 then --enter
      -- Enter
      local px,py=scrPosToRaw(x,y)
      newline()
      onChange("newline","",px,py)
      closeChange() --never group enters together
    elseif param == 29 or param == 157 then  --left or right ctrl
      closeChange()
      -- open top level menus
      bMenu = true
      sMenuTitle=""
      tMenuStack[1]=tMenuItems
      term.setCursorBlink( false )
      nMenuItem = 1
      redrawMenu()
    end
  elseif sEvent == "char" then
    -- Input text
    local px,py=scrPosToRaw(x,y)
    if param=="%" and nViewMode==3 then
      insert("%%")
    else
      insert(param)
    end
    onChange("char",param,px,py)
  elseif sEvent == "timer" and param==hChangeTimer then
    closeChange()
  elseif sEvent == "ctrl-char" then
    if tDocCtrlKeys[param] then
      confirmAndDo(tDocCtrlKeys[param])
      redrawMenu()
    end
  end
end


function formInputHandler(sEvent,param)
  if sEvent=="key" then
    if param==keys.leftCtrl or param==keys.rightCtrl then
      tActiveForm=nil
      redrawText()
    elseif param==208 then --down
      nSelectedField=nSelectedField+1
      if nSelectedField>#tActiveForm then
        nSelectedField=1
      end
      updateFormCursorPos()
      redrawForm()
    elseif param==200 then --up
      nSelectedField=nSelectedField-1
      if nSelectedField==0 then
        nSelectedField=#tActiveForm
        updateFormCursorPos()
      end
      redrawForm()
    elseif param==14 then --backspace
      local tField=tActiveForm[nSelectedField]
      if tField.type=="number" then
        if tField.value>0 then
          tField.value=math.floor(tField.value/10)
          redrawForm()
        end
      elseif tField.type=="string" then
        if #tField.value>0 then
          tField.value=string.sub(tField.value,1,#tField.value-1)
          nFieldCursorX=nFieldCursorX-1
          redrawForm()
        end
      end
    end
  elseif sEvent=="char" then
    --edit the field's value...fun stuff here
    local tField=tActiveForm[nSelectedField]
    if tField.type=="number" then
      --numbers only
      if param>="0" and param<="9" then
        if #tostring(tField.value)<tField.nFieldWidth then
          tField.value=tField.value*10+tonumber(param)
          redrawForm()
        end
      end

    elseif tField.type=="boolean" then
      if param=="n" or param=="N" then
        tField.value=false
        redrawForm()
      elseif param=="y" or param=="Y" then
        tField.value=true
        redrawForm()
      elseif param==" " then
        tField.value=not tField.value
        redrawForm()
      end
    end
  elseif tField.type=="string" then
    if #tField.value<tField.nFieldWidth then
      tField.value=tField.value..param
      nFieldCursorX=nFieldCursorX+1
      redrawForm()
    end
  end
end

function menuInputHandler(sEvent,param)
  if sEvent == "key" then
    if param == 203 then --left
      -- Move menu left
      nMenuItem = nMenuItem - 1
      if nMenuItem < 1 then
        nMenuItem = #tMenuStack[#tMenuStack]
      end
      redrawMenu()
    elseif param == 205 then --right
      -- Move menu right
      nMenuItem = nMenuItem + 1
      if nMenuItem > #tMenuStack[#tMenuStack] then
        nMenuItem = 1
      end
      redrawMenu()
    elseif param == 28 then --enter
      -- Menu selection
      doMenuItem( nMenuItem )
    elseif param == 29 or param == 157 then  --left or right control
      -- Menu toggle
      if #tMenuStack>1 then
        tMenuStack[#tMenuStack]=nil
        nMenuItem=1
      else
        tMenuStack={}
        term.setCursorBlink( true )
      end
      redrawMenu()
    end
  elseif sEvent == "char" then
    -- Select menu items
    local tMenu=tMenuStack[#tMenuStack]
    for n,sMenuItem in ipairs( tMenu ) do
      if sMenuItem.hotkey == string.lower(param) then
        doMenuItem( n )
        break
      end
    end
  elseif sEvent == "ctrl-char" then
    -- Menu toggle
    tMenuStack={}
    term.setCursorBlink( true )
    if tActiveForm==nil then
      if tDocCtrlKeys[param] then
        confirmAndDo(tDocCtrlKeys[param])
      end
    end
    redrawMenu()
  end
end


--[[
local line="[%%%1]"
print("line : \n"..line)
print("---")
local lines=getStrippedLine(line,1)
print("stripped line mode 1: \n123456789012345678901234567890123456789\n"..lines[1].s)


tLinesRaw={line}
local stripped=getStrippedLine(line,1)
tLinesDrawn={{s=stripped[1].s,raw=1,offsetRaw=0,offsetCol=0}}

local first=nil
for i=1,#stripped[1].s do
  local sCh=string.sub(line,i,i)
  local ri=scrColToIndex(line,i,1)
  local rCh=string.sub(line,ri,ri)
  --back to index
  local px,py=  rawToScrPos(ri,1,3)

  print("col "..i.."=> index "..ri.." => "..px)
end

if first then print("first error at "..first) end

--]]
---[[

-- Actual program functionality begins
load(sPath)

nViewMode=1
rebuildText()

term.clear()
term.setCursorPos(x,y)
term.setCursorBlink( true )

redrawText()
redrawMenu()

--key->char lookup table for keys that map to chars
local keyToChar={[2]="1",[3]="2",[4]="3",[5]="4",[6]="5",[7]="6",[8]="7",[9]="8",[10]="9",[11]="0",[12]="minus",[13]="equals",[16]="q",[17]="w",[18]="e",[19]="r",[20]="t",[21]="y",[22]="u",[23]="i",[24]="o",[25]="p",[26]="leftBracket",[27]="rightBracket",[30]="a",[31]="s",[32]="d",[33]="f",[34]="g",[35]="h",[36]="j",[37]="k",[38]="l",[39]="semiColon",[40]="apostrophe",[41]="grave",[43]="backslash",[44]="z",[45]="x",[46]="c",[47]="v",[48]="b",[49]="n",[50]="m",[51]="comma",[52]="period",[53]="slash",}

-- Handle input
local eventBuffer={}
while bRunning do
  local function nextEvent(eventBuffer)
    if #eventBuffer>0 then
      local e,p=unpack(eventBuffer[1])
      table.remove(eventBuffer,1)
      return e,p
    else
      return os.pullEvent()
    end
  end

  local sEvent, param = nextEvent(eventBuffer)
  --identify ctrl-char events at top level
  if sEvent=="key" and keyToChar[param]~=nil then
    local tempBuff={}
    local timer=os.startTimer(0)
    while true do
      e2,p2=nextEvent(eventBuffer)
      --if it's a char event, and it matches the original key...
      if e2=="char" and keyToChar[param]==string.lower(p2) then
        tempBuff[#tempBuff+1]={e2,p2}
        break
      elseif e2=="timer" and p2==timer then
        --no matching char event, this is a ctrl-char key!
        local ch=keyToChar[param]
        if ch=="0" then
          ch="zero"
        elseif ch>="1" and ch<="9" then
          ch=({"one","two","three","four","five","six","seven","eight","nine"})[tonumber(ch)]
        end
        os.queueEvent("ctrl-char",ch)
        break
      else
        --anything else we get buffer, so we can use them in order
        tempBuff[#tempBuff+1]={e2,p2}
      end
    end
    --prepend tempBuffer to eventBuffer, again preserving original order
    for i=1,#eventBuffer do
      tempBuff[#tempBuff+i]=eventBuffer[i]
    end
    eventBuffer=tempBuff
  end

  if #tMenuStack>0 then
    menuInputHandler(sEvent,param)
  elseif tActiveForm then
    formInputHandler(sEvent,param)
  else
    docInputHandler(sEvent,param)
  end
end

-- Cleanup
term.clear()
term.setCursorBlink( false )
term.setCursorPos( 1, 1 )
--]]