vil.lua

vos.loadApi('core.api')
vos.loadApi('ui.api')

Logger.disable()
local assert = vos.assert

local commandBuffer = ''
local commandCount
local x, y = 1, 1
local scrollx, scrolly = 0, 0
local lines = {}
local clipboard = nil
local autoClearStatus = false
local fileInfo = {
  modified = false,
}

-- forward declarations
local keyMappings = { }
local keyMapping
local keyFunctions

local function isAdvanced() return term.isColor and term.isColor() end
local colorTheme = {
  editorBackground = "black",
  normal = {
    lineNumbersText = "gray",
  },
  highlight = {
    lineNumbersText = 'white',
  },
  textColor = "white",
  conditional = "yellow",
  constant = "red",
  ["function"] = "magenta",
  language = 'cyan',
  ["table"] = 'lime',
  string = "red",
  comment = "lime"
}

local standardTheme = {
  editorBackground = "black",
  editorLineHighlight = "black",
  editorLineNumbers = "black",
  editorLineNumbersHighlight = "white",
  editorError = "black",
  editorErrorHighlight = "black",

  textColor = "white",
  conditional = "white",
  constant = "white",
  ["function"] = "white",
  string = "white",
  comment = "white"
}

-- Load Theme
local theme = standardTheme
if isAdvanced() then
  theme = colorTheme
end

keywords = {
  ["and"] = "conditional",
  ["break"] = "conditional",
  ["do"] = "conditional",
  ["else"] = "conditional",
  ["elseif"] = "conditional",
  ["for"] = "conditional",
  ["if"] = "conditional",
  ["in"] = "conditional",
  ["local"] = "conditional",
  ["not"] = "conditional",
  ["or"] = "conditional",
  ["repeat"] = "conditional",
  ["return"] = "conditional",
  ["then"] = "conditional",
  ["until"] = "conditional",
  ["while"] = "conditional",

--[[
  ['{'] = 'table',
  ['}'] = 'table',
--]]

  ["function"] = "language",
  ["end"] = "language",
  ["pairs"] = "language",
  ["ipairs"] = "language",
  ["rawset"] = "language",
  ["rawget"] = "language",
  ["print"] = "language",

  ["true"] = "constant",
  ["false"] = "constant",
  ["nil"] = "constant",

  ["write"] = "function",
  ["sleep"] = "function",
  ["loadstring"] = "function",
  ["loadfile"] = "function",
  ["dofile"] = "function",
  ["setfenv"] = "function",
  ["getfenv"] = "function",
}

local standardsCompletions = {
  "if%s+.+%s+then%s*$",
  "for%s+.+%s+do%s*$",
  "while%s+.+%s+do%s*$",
  "repeat%s*$",
  "function%s+[a-zA-Z_0-9]?\(.*\)%s*$",
  "=%s*function%s*\(.*\)%s*$",
  "else%s*$",
  "elseif%s+.+%s+then%s*$"
}

local liveCompletions = {
  ["("] = ")",
  ["{"] = "}",
  ["["] = "]",
  ["\""] = "\"",
  ["'"] = "'",
}

local function hackyRead()
  -- stops read from scrolling screen
  local oldPrint = _G.print
  _G.print = function() end
  local result = read()
  _G.print = oldPrint
  result = Util.trim(result)
  if #result > 0 then
    return result
  end
end

local editor = UI.Page({
  settings = {
    tabWidth = 2,
  },
  gutter = UI.Window({
    width = 3,
    height = UI.term.height - 1,
  }),
  editArea = UI.Window({
    x = 4,
    y = 1,
    width = UI.term.width - 3,
    height = UI.term.height - 1,
    dirty = { },
    focus = function() end,
  }),
  statusBar = UI.StatusBar({
    backgroundColor = colors.black,
    columns = {
      { '', 'status', UI.term.width - 10 },
      { '', 'cursor', 8 }
    },
  }),
})

local gutter = editor.gutter
local editArea = editor.editArea
local statusBar = editor.statusBar

function editor:draw()
  term.setCursorBlink(false)
  term.setBackgroundColor(colors.black)

  editArea:draw()
  statusBar:draw()

  term.setTextColor(colors[theme.textColor])
  term.setCursorPos(x - scrollx + editArea.x - 1, y - scrolly)
  term.setCursorBlink(true)
end

function editor:flashScreen()
  term.setBackgroundColor(colors.lightGray)
  term.clear()
  os.sleep(0)
  editArea:markScreenDirty()
end

--[[ STATUSBAR AREA ]]--
function statusBar:showMessage(str, ...)
  assert('statusBar:showMessage', {
    { 'string', str },
  })
  self:setValue('status', str:format(...))
  self:draw()
end

function statusBar:clearMessage()
  self:showMessage('')
end

function statusBar:showError(status)
  term.setCursorPos(1, statusBar.y)
  term.setBackgroundColor(colors.red)
  term.setTextColor(colors.white)
  term.write(status)
  term.setBackgroundColor(colors[theme.editorBackground])
end

function statusBar:draw()
  if commandBuffer or commandCount then
    self:setValue('cursor', tostring(commandCount or 1) .. tostring(commandBuffer or ''))
  else
    self:setValue('cursor', string.format('%d,%d', y, x))
  end
  UI.StatusBar.draw(self)
end

--[[ EDIT AREA ]]--
function editArea:attemptToHighlight(line, regex, col)
  local match = string.match(line, regex)
  if match then
    if type(col) == "number" then
      term.setTextColor(col)
    elseif type(col) == "function" then
      term.setTextColor(col(match))
    end
    term.write(match)
    term.setTextColor(colors[theme.textColor])
    return line:sub(match:len() + 1, -1)
  end
  return nil
end

function editArea:writeHighlighted(line)
  while line:len() > 0 do
    line = self:attemptToHighlight(line, "^%-%-%[%[.-%]%]", colors[theme.comment]) or
           self:attemptToHighlight(line, "^%-%-.*", colors[theme.comment]) or
           self:attemptToHighlight(line, "^\".*[^\\]\"", colors[theme.string]) or
           self:attemptToHighlight(line, "^\'.*[^\\]\'", colors[theme.string]) or
           self:attemptToHighlight(line, "^%[%[.-%]%]", colors[theme.string]) or
           self:attemptToHighlight(line, "^[%w_]+", function(match)
             if keywords[match] then
               return colors[theme[keywords[match]]]
             end
               return colors[theme.textColor]
             end) or
           self:attemptToHighlight(line, "^[^%w_]", colors[theme.textColor])
  end
end

function editArea:drawLine(ly)
  if (ly - scrolly < 1) or (ly - scrolly > editArea.height) then
    return
  end

  term.setCursorPos(1, ly - scrolly)
  if ly <= #lines then
    local _colors = theme.normal
    if ly == y then
      _colors = theme.highlight
    end

    term.setTextColor(colors[_colors.lineNumbersText])
    local ln = string.rep(" ", gutter.width - 1 - tostring(ly):len()) .. tostring(ly)
    term.write(ln .. ' ')

    local a = lines[ly]
    local totalWidth = self.width
    if scrollx > 0 then
      totalWidth = self.width + scrollx
      term.setCursorPos(1 - scrollx + self.x, ly - scrolly)
    end
    self:writeHighlighted(a)
    if #a < totalWidth then
      term.write(string.rep(' ', totalWidth - #a))
    end
  else
    term.clearLine()
  end
end

function editArea:drawDirty()
  local keys = Util.keys(self.dirty)
  for _,lineNo in pairs(keys) do
    self:drawLine(lineNo)
    self.dirty[lineNo] = nil
  end
end

function editArea:markDirty(ls)
  assert('editor:markDirty', {
    { 'table', ls },
  })
  for _, ly in pairs(ls) do
    self.dirty[ly] = true
  end
end

function editArea:markSubsequentDirty(lineNo)
  for i = lineNo - scrolly, self.height do
    self.dirty[i + scrolly] = true
  end
end

function editArea:markScreenDirty()
  for i = 1, self.height do
    self.dirty[scrolly + i] = true
  end
  if autoClearStatus then
    statusBar:setValue('status', '')
  end
end

function editArea:draw()
  local gutterWidth = math.max(tostring(#lines):len() + 1, 3)
  if gutterWidth ~= gutter.width then
    gutter.width = gutterWidth
    editArea.width = editor.width - gutter.width
    editArea.x = gutter.width + 1
    self:markScreenDirty()
  end
  if not Util.empty(self.dirty) then
    --local ds = 'ds: ' .. table.concat(Util.keys(self.dirty), ',')
    --editor.statusBar:setValue('status', ds)
    self:drawDirty()
  end
end

function editArea:cursorLoc(newX, newY)

  if newY > #lines then
    newY = #lines
  elseif newY < 1 then
    newY = 1
  end
  if y ~= newY then
    self:markDirty({ y, newY })
  end
  y = newY

  if newX < 1 then
    newX = 1
  elseif newX > #lines[y] + 1 then
    newX = #lines[y] + 1
  end
  x = newX

  if y > #lines then
    y = #lines
  end

  local force = false
  local sx, sy = x - scrollx, y - scrolly
  local oscrollx, oscrolly = scrollx, scrolly

  if sx < 1 then
    scrollx = x - 1
    force = true
  elseif sx > self.width then
    scrollx = x - self.width
    force = true
  end
  if sy < 1 then
    scrolly = y - 1
  elseif sy > self.height then
    scrolly = y - self.height
  end

  local scrolledy = scrolly - oscrolly
  if (math.abs(scrolledy) >= self.height) then
    force = true
  end

  if force or scrolledy ~= 0 then
    if autoClearStatus then
      editor.statusBar:setValue('status', '')
    end
  end

  if force then
    self:markScreenDirty()
  elseif scrolledy ~= 0 then
    term.scroll(scrolledy)
    if scrolledy > 0 then
      statusBar:clear()
--      term.setCursorPos(1, statusBar.y)
--      term.clearLine()
      self:markSubsequentDirty(scrolly + self.height - scrolledy + 1)
    else
      for i = -1, scrolledy, -1 do
        self:markDirty({ scrolly - i })
      end
    end
  end
end

function getFileInfo(path)
  local abspath = "/" .. shell.resolve(path)

  local fi = {
    abspath = abspath,
    path = path,
    name = fs.getName(path),
    dir = fs.getDir(abspath),
    isNew = not fs.exists(abspath),
    isDir = fs.isDir(path),
    dirExists = fs.exists(fs.getDir(abspath)),
    modified = false,
  }
  if fi.isDir then
    fi.isReadOnly = true
  else
    fi.isReadOnly = fs.isReadOnly(fi.abspath)
  end

  return fi
end

function resetCommandBuffer()
  commandBuffer = nil
  commandCount = nil
end

function newFile()
  local fi = {
    isNew = true,
    isDir = false,
    dirExists = false,
    modified = false,
    isReadOnly = false,
  }
end

function load(path)

  fileInfo = getFileInfo(path)

  if fileInfo.isNew then
    lines = { '' }
  else
    if fileInfo.isDir then
      lines = fs.list(fileInfo.abspath)
    else
      lines = Util.readLines(fileInfo.abspath) or { '' }
    end
  end

  multishell.setTitle(TAB_ID, fileInfo.name)
  editArea:markScreenDirty()

  local status = fileInfo.path
  if fileInfo.isNew then
    if not fileInfo.dirExists then
      statusBar:showMessage('"%s" [New DIRECTORY]', path)
    else
      statusBar:showMessage('"%s" [New File]', path)
    end
  elseif fileInfo.isDir then
    statusBar:showMessage('"%s" is a directory')
  elseif fileInfo.isReadOnly then
    statusBar:showMessage('"%s" [readonly] %dL, %dC',
          path, #lines, fs.getSize(fileInfo.abspath))
  else
    statusBar:showMessage('"%s" %dL, %dC',
          path, #lines, fs.getSize(fileInfo.abspath))
  end
end

local function saveFile(path)
  local dir = path:sub(1, path:len() - fs.getName(path):len())
  if not fs.exists(dir) then
    fs.makeDir(dir)
  end

  if fs.isDir(path) then
    return false, string.format('"%s" is a directory', path)
  end

  if fs.isReadOnly(path) then
    return false, string.format('"%s" is read only', path)
  end

  if not Util.writeLines(path, lines) then
    return false, string.format('Error saving "%s"', path)
  end

  return true
end

keyFunctions = {
  commandMode = function()
    statusBar:clearMessage()
    autoClearStatus = true
    keyMapping = keyMappings['vi-command']
  end,
  insertMode = function(event)
    statusBar:showMessage('-- INSERT --')
    autoClearStatus = false
    keyMapping = keyMappings['vi-insert']
    if event.key == 'a' then
      keyFunctions.right()
    elseif event.key == 'A' then
      keyFunctions.lineEnd()
    elseif event.key == 'o' then
      keyFunctions.appendLine()
    elseif event.key == 'O' then
      keyFunctions.insertLine()
    end
  end,
  up = function(event)
    if y > 1 then
      editArea:cursorLoc(x, y - (event.count or 1))
      return true
    end
  end,
  down = function(event)
    if y < #lines then
      editArea:cursorLoc(x, y + (event.count or 1))
      return true
    end
  end,
  left = function(event)
    if x > 1 then
      editArea:cursorLoc(x - (event.count or 1), y)
      return true
    end
  end,
  right = function(event)
    if x < lines[y]:len() + 1 then
      editArea:cursorLoc(x + (event.count or 1), y)
      return true
    end
  end,
  leftWrap = function()
    if x > 1 then
      editArea:cursorLoc(x - 1, y)
      return true
    end
    if y > 1 then
      editArea:cursorLoc(#lines[y - 1] + 1, y - 1)
      return true
    end
  end,
  rightWrap = function()
    if x < lines[y]:len() + 1 then
      editArea:cursorLoc(x + 1, y)
      return true
    end
    if y < #lines then
      editArea:cursorLoc(1, y + 1)
      return true
    end
  end,
  home = function()
    editArea:cursorLoc(1, y)
    return true
  end,
  lineEnd = function()
    editArea:cursorLoc(lines[y]:len() + 1, y)
    return true
  end,
  gotoLine = function(event)
    if not event.count then
      editArea:cursorLoc(1, #lines)
      return true
    end
    if event.count > #lines then
      return false
    end
    editArea:cursorLoc(1, event.count)
    return true
  end,
  pageUp = function()
    if scrolly > 0 then
      editArea:cursorLoc(x, math.min(math.max(y - editArea.height, 1), #lines))
      return true
    end
  end,
  pageDown = function()
    editArea:cursorLoc(x, math.min(math.max(y + editArea.height, 1), #lines))
  end,
  quit = function(event)
    if fileInfo.modified and event.key ~= ':q!' then
      return false, 'No write since last change (add ! to override)'
    end
    Event.exitPullEvents()
    return #event.key
  end,
  abort = function()
    Event.exitPullEvents()
  end,
  status = function()
    local path = fileInfo.path or '[No Name]'
    if #lines == 0 then
      statusBar:showMessage('"%s" -- No lines in buffer --', path)
    else
      statusBar:showMessage('"%s" %d lines --%d%%--',
           fileInfo.path, #lines, math.floor(y/#lines*100))
    end
    return true
  end,
  save = function()
    saveFile(fileInfo.abspath)
    statusBar:showMessage('"%s" %dL, %dC written',
           fileInfo.path, #lines, fs.getSize(fileInfo.abspath))
  end,
  cutLine = function()
    clipboard = lines[y]
    table.remove(lines, y)
    editArea:markSubsequentDirty(y)
    editArea:cursorLoc(1, y)
    fileInfo.modified = true
  end,
  copyLines = function(event)
    clipboard = { }
    local count = math.min(event.count or 1, #lines - y)
    for i = 1, event.count do
      table.insert(clipboard,  lines[y + i - 1])
    end
    statusBar:showMessage('%d lines yanked', count)
  end,
  appendLine = function()
    table.insert(lines, y + 1, '')
    editArea:markSubsequentDirty(y + 1)
    editArea:cursorLoc(1, y + 1)
    fileInfo.modified = true
  end,
  insertLine = function()
    table.insert(lines, y, '')
    editArea:markSubsequentDirty(y)
    editArea:cursorLoc(1, y)
    fileInfo.modified = true
  end,
  enter = function()
    local f = nil
    local oldy = y
    for _, v in pairs(standardsCompletions) do
      if lines[y]:find(v) then f = v end
    end

    local _, spaces = lines[y]:find("^[ ]+")
    if not spaces then spaces = 0 end
    if f then
      table.insert(lines, y + 1, string.rep(" ", spaces + 2))
      if not f:find("else", 1, true) and not f:find("elseif", 1, true) then
        table.insert(lines, y + 2, string.rep(" ", spaces) ..
          (f:find("repeat", 1, true) and "until " or f:find("{", 1, true) and "}" or "end"))
      end
      editArea:cursorLoc(spaces + 3, y + 1)
    else
      local oldLine = lines[y]
      lines[y] = lines[y]:sub(1, x - 1)
      table.insert(lines, y + 1, string.rep(" ", spaces) .. oldLine:sub(x, -1))
      editArea:cursorLoc(spaces + 1, y + 1)
    end
    editArea:markSubsequentDirty(oldy)
    fileInfo.modified = true
  end,
  backspace = function()
    if x > 1 then
      local f = false
      for k, v in pairs(liveCompletions) do
        if lines[y]:sub(x - 1, x - 1) == k then f = true end
      end
      lines[y] = lines[y]:sub(1, x - 2) .. lines[y]:sub(x + (f and 1 or 0), -1)
      editArea:markDirty({ y })
      editArea:cursorLoc(x - 1, y)
      fileInfo.modified = true
    elseif y > 1 then
      local prevLen = lines[y - 1]:len() + 1
      lines[y - 1] = lines[y - 1] .. lines[y]
      table.remove(lines, y)
      editArea:markSubsequentDirty(y - 1)
      editArea:cursorLoc(prevLen, y - 1)
      fileInfo.modified = true
    end
  end,
  delete = function()
    if x < lines[y]:len() + 1 then
      lines[y] = lines[y]:sub(1, x - 1) .. lines[y]:sub(x + 1)
      editArea:markDirty({ y })
--      editArea:cursorLoc(x, y)
      fileInfo.modified = true
    elseif y < #lines then
      lines[y] = lines[y] .. lines[y + 1]
      table.remove(lines, y + 1)
      editArea:markSubsequentDirty(y)
--      editArea:cursorLoc(x, y)
      fileInfo.modified = true
    end
  end,
  deleteToEnd = function()
    lines[y] = lines[y]:sub(1, x - 1)
    editArea:markDirty({ y })
    editArea:cursorLoc(#lines[y], y)
    fileInfo.modified = true
  end,
  tab = function()
    lines[y] = string.rep(" ", editor.settings.tabWidth) .. lines[y]
    editArea:markDirty({ y })
    editArea:cursorLoc(x + 2, y)
    fileInfo.modified = true
  end,
  insertCharacter = function(event)
    local key = event.key
    local shouldIgnore = false
    for k, v in pairs(liveCompletions) do
      if key == v and lines[y]:find(k, 1, true) and lines[y]:sub(x, x) == v then
        shouldIgnore = true
      end
    end
    local addOne = false
    if not shouldIgnore then
      for k, v in pairs(liveCompletions) do
        if key == k and lines[y]:sub(x, x) ~= k then
          key = key .. v
          addOne = true
        end
      end
      lines[y] = lines[y]:sub(1, x - 1) .. key .. lines[y]:sub(x, -1)
    end

    editArea:markDirty({ y })
    editArea:cursorLoc(x + (addOne and 1 or key:len()), y)
    fileInfo.modified = true
  end,
  pasteLine = function()
    if clipboard then
      table.insert(lines, y, clipboard)
      editArea:markSubsequentDirty(y)
      statusBar:showMessage('1 more line')
      fileInfo.modified = true
    end
  end,
  nextWord = function()
    local str = lines[y]
    local result = { str:find("(%w+)", x) }
    if #result > 0 and result[1] == x then
      result = { str:find("(%w+)", result[2] + 1) }
    end
    if #result > 0 then
      if #result > 0 then
        editArea:cursorLoc(result[1], y)
      end
    elseif #result == 0 and y < #lines then
      local nx
      result = { lines[y + 1]:find("(%w+)", 1) }
      if #result == 0 then
        nx = 1
      else
        nx = result[1]
      end
      editArea:cursorLoc(nx, y + 1)
    end
  end,
  deleteLines = function(event)
    clipboard = { }
    for i = 1, (event.count or 1) do
      table.insert(clipboard, lines[y])
      table.remove(lines, y)
    end
    if #lines == 0 then
      table.insert(lines, '')
    end
    editArea:cursorLoc(1, y)
    editArea:markSubsequentDirty(y)
    fileInfo.modified = true
  end,
  pasteLinesBefore = function()
    if clipboard and type(clipboard) == 'table' then
      for i = 1, #clipboard do
        table.insert(lines, y + i - 1, clipboard[i])
      end
      editArea:cursorLoc(1, y)
      editArea:markSubsequentDirty(y)
      fileInfo.modified = true
    end
  end,
  searchPrompt = function()
    term.setCursorPos(1, statusBar.y)
    term.write('/')
    hackyRead()
  end,
  nextLine = function()
    if y < #lines then
      editArea:cursorLoc(1, y + 1)
    end
  end,
  write = function(event)
    local fi = fileInfo
    if event.args then
      fi = getFileInfo(event.args)
    end
    if fi.isReadOnly then
      return false, "'readonly' option is set"
    end

    if event.args and fs.exists(fi.path) and not event.key:find(1, '!', true) then
      return false, 'File exists (add ! to override)'
    end
    local success, msg = saveFile(fi.path)
    if not success then
      return false, msg
    end
    fi.modified = false
    statusBar:showMessage('"%s" %dL, %dC written',
          filename, #lines, fs.getSize(filename))
    if event.key:sub(2, 1) == '!' then
      return 2
    end
    return 1
  end,
  colonPrompt = function(event)
    term.setCursorPos(1, statusBar.y)
    term.clearLine()
    term.write(':')
    local cmd = hackyRead()
    statusBar:clearMessage()
    if cmd then
      local words = Util.toWords(cmd)
      local cmd = words[1]
      local index = 1
      repeat
        local subcmd = ':' .. cmd:sub(index, 1)
        if not keyMapping[subcmd] then
          statusBar:showError('Invalid command')
          break
        end
        event.key = ':' .. cmd:sub(index)
        event.args = words[2]
        local inc, msg = keyMapping[subcmd](event)
        if not inc then
          statusBar:showError(msg)
          break
        end
        index = index + inc
      until index > #cmd
    end
  end,
  refresh = function()
    editArea:markScreenDirty()
  end,
  insertTranslate = function(event)
    if #event.key == 1 then
      return keyFunctions.insertCharacter
    end
    return keyMapping[event.key]
  end,
  commandTranslate = function(event)

    local filterKeys = {
      [ 'leftCtrl'  ] = true,
      [ 'leftAlt'   ] = true,
      [ 'leftShift' ] = true,
      [ ' '         ] = true,
    }
    if filterKeys[event.key] then
      return function() return true end
    end

    if commandBuffer and #event.key > 1 then
      return resetCommandBuffer
    end

    if #event.key == 1 then
      local ch = tonumber(event.key)
      if ch then
        if commandCount then
          commandCount = commandCount * 10 + ch
        else
          commandCount = ch
        end
        commandBuffer = nil
        return
      end

      if not commandBuffer then
        commandBuffer = event.key
      else
        commandBuffer = commandBuffer .. event.key
      end
      event.key = commandBuffer
    end

    local fn = keyMapping[event.key]
    if fn then
      event.count = commandCount
      commandBuffer = nil
      commandCount = nil
      return fn
    end

    for k,_ in pairs(keyMapping) do
      if k:find('^' .. event.key) then
        return
      end
    end

    --statusBar:showMessage(tostring(event.key))
    --autoClearStatus = false
    return resetCommandBuffer
  end,
}

local commonKeyMapping = {
  [ 'up'        ] = keyFunctions.up,
  [ 'down'      ] = keyFunctions.down,
  [ 'left'      ] = keyFunctions.left,
  [ 'right'     ] = keyFunctions.right,
  [ 'home'      ] = keyFunctions.home,
  [ 'end'       ] = keyFunctions.lineEnd,
  [ 'pageUp'    ] = keyFunctions.pageUp,
  [ 'pageDown'  ] = keyFunctions.pageDown,
  [ 'control-t' ] = keyFunctions.abort,
}

local colonCommands = {
    [ 'w'         ] = keyFunctions.write,
    [ 'r'         ] = keyFunctions.notImplemented,
    [ 'e'         ] = keyFunctions.notImplemented,
    [ 'vi'        ] = keyFunctions.notImplemented,

    [ '!!'        ] = keyFunctions.notImplemented,
    [ '^!(%S)'    ] = keyFunctions.run,
    [ 'sh'        ] = keyFunctions.notImplemented,

    [ 'set'       ] = keyFunctions.notImplemented,

    [ 'q'         ] = keyFunctions.quit,
}

local keyMappingsSource = {
  [ 'vi-command'  ] = {

    [ 'translate' ] = keyFunctions.commandTranslate,

    -- insert
    [ 'i'         ] = keyFunctions.insertMode,
    [ 'I'         ] = keyFunctions.notImplemented,
    [ 'a'         ] = keyFunctions.insertMode,
    [ 'A'         ] = keyFunctions.insertMode,
    [ 'o'         ] = keyFunctions.insertMode,
    [ 'O'         ] = keyFunctions.insertMode,
    [ 'r'         ] = keyFunctions.notImplemented,
    [ 'R'         ] = keyFunctions.notImplemented,

    -- motion
    [ 'h'         ] = keyFunctions.left,
    [ 'j'         ] = keyFunctions.down,
    [ 'k'         ] = keyFunctions.up,
    [ 'l'         ] = keyFunctions.right,
    [ 'w'         ] = keyFunctions.nextWord,
    [ 'b'         ] = keyFunctions.notImplemented,
    [ '^'         ] = keyFunctions.notImplemented,
    [ 'space'     ] = keyFunctions.rightWrap,
    [ '0'         ] = keyFunctions.home,
    [ '$'         ] = keyFunctions.lineEnd,
    [ 'G'         ] = keyFunctions.gotoLine,
    [ 'control-f' ] = keyFunctions.pageDown,
    [ 'control-b' ] = keyFunctions.pageUp,
    [ 'backspace' ] = keyFunctions.leftWrap,

    -- deleting
    [ 'x'         ] = keyFunctions.delete,
    [ 'X'         ] = keyFunctions.notImplemented,
    [ 'D'         ] = keyFunctions.deleteToEnd,
    [ 'dd'        ] = keyFunctions.deleteLines,
    [ 'dw'        ] = keyFunctions.notImplemented,

    -- status
    [ 'control-g' ] = keyFunctions.status,

    -- paste
    [ 'p'         ] = keyFunctions.pasteLinesAfter,
    [ 'P'         ] = keyFunctions.pasteLinesBefore,
    [ 'yy'        ] = keyFunctions.copyLines,

    -- changing text
    [ 'C'         ] = keyFunctions.notImplemented,
    [ 'cc'        ] = keyFunctions.notImplemented,
    [ 'cw'        ] = keyFunctions.notImplemented,

    -- searching
    [ 'n'         ] = keyFunctions.notImplemented,
    [ 'N'         ] = keyFunctions.notImplemented,

    [ '/'         ] = keyFunctions.searchPrompt,
    [ 'enter'     ] = keyFunctions.nextLine,
    [ ':'         ] = keyFunctions.colonPrompt,

    [ 'ZZ'        ] = keyFunctions.notImplemented,
    [ 'control-l' ] = keyFunctions.refresh,
  },
  [ 'vi-insert'   ] = {
    [ 'leftAlt'   ] = keyFunctions.commandMode,
    [ 'enter'     ] = keyFunctions.enter,
    [ 'backspace' ] = keyFunctions.backspace,
    [ 'delete'    ] = keyFunctions.delete,
    [ 'tab'       ] = keyFunctions.tab,
    [ 'default'   ] = keyFunctions.default,
    [ 'translate' ] = keyFunctions.insertTranslate,
  },
  [ 'fullscreen'  ] = {
    [ 'control-g' ] = keyFunctions.status,
    [ 'control-s' ] = keyFunctions.save,
    [ 'control-x' ] = keyFunctions.cutLine,
    [ 'control-c' ] = keyFunctions.copyLines,
    [ 'contol-v'  ] = keyFunctions.pasteLine,
    [ 'right'     ] = keyFunctions.rightWrap,
    [ 'left'      ] = keyFunctions.leftWrap,
    [ 'enter'     ] = keyFunctions.enter,
    [ 'backspace' ] = keyFunctions.backspace,
    [ 'delete'    ] = keyFunctions.delete,
    [ 'tab'       ] = keyFunctions.tab,
    [ 'default'   ] = keyFunctions.default,
  },
}

for k,v in pairs(keyMappingsSource) do
  keyMappings[k] = Util.shallowCopy(commonKeyMapping)
  Util.merge(keyMappings[k], v)
end

keyMapping = keyMappings['vi-command']

function editArea:eventHandler(event)

  if event.type == 'paste' then
    event.type = 'key'
    event.key = 'contol-v'
  end

  if event.type == 'key' then
    local fn = keyMapping.translate(event)
    if fn then
      if not fn(event) then
        editor:flashScreen()
      end
    end
  elseif event.type == "mouse_click" then
    editArea:cursorLoc(scrollx + event.x, scrolly + event.y)
  else
    return false
  end

  editor:draw()
  return true
end

local function main(arguments)

  if #arguments > 0 then
    load(arguments[1])
  else
    newFile()
  end

  term.setBackgroundColor(colors[theme.editorBackground])
  UI.pager:setPage(editor)

--  autoClearStatus = true

  Event.pullEvents()
end

local args = {...}
local _, err = pcall(function()
  main(args)
end)

term.setTextColor(colors.white)
if not err then
  term.clear()
  term.setCursorPos(1, 1)
end

-- Catch errors
if err and not err:find("Terminated") then
  print(err)
end