myturtle(API)

-- -------------------------------
-- my turtle(API)
-- -------------------------------
-- ---------------
-- Move/Dig Functions
-- ---------------
function surelyUp()
  while not turtle.up() do turtle.digUp() end
end
function surelyDown()
  while not turtle.down() do turtle.digDown() end
end
-- http://hevohevo.hatenablog.com/entry/2014/07/14/213109
function surelyDigUp()
  while turtle.digUp() do
    os.sleep(0.4)
  end
end
-- http://hevohevo.hatenablog.com/entry/2014/07/14/213109
function surelyDig()
  while turtle.dig() do end
end
-- http://hevohevo.hatenablog.com/entry/2014/07/14/213109
function surelyFwd()
  for i=1,4 do
    local status, err = turtle.forward()
    if status then
      return true  -- success!
    elseif err=="Out of fuel" then
      return status, err
    end

    surelyDig() -- face to a normal block or a sand(gravel) hill

    if turtle.detect() and not turtle.dig() then
      return false, "bedrock!"
    end

    if turtle.forward() then return true end -- success!

    if turtle.attack() then
      -- face to monster-mob
      while turtle.attack() do end
    else
      -- face to sand-blocks which is dropping long time
      os.sleep(5) -- probably, adjustment is required
    end
  end
  return turtle.forward()
end
-- ---------------
-- vacuum
-- ---------------
function vacuum(slotNo)
  local result = false
  turtle.select(slotNo)
  for i = 1, 16 do
    if slotNo ~= i and turtle.compareTo(i) and 1 < turtle.getItemCount(i) then
      turtle.select(i)
      turtle.transferTo(slotNo, turtle.getItemSpace(slotNo))
      result = true
      if 0 == turtle.getItemSpace(slotNo) then
        break
      end
      turtle.select(slotNo)
    end
  end
  turtle.select(slotNo)
  return result
end
-- ---------------
-- refuelPrompt
-- ---------------
function refuelPrompt(moveFunc)
  local firstTime = true;
  while true do
    local rslt, msg;
    if nil ~= moveFunc then
      rslt, msg = moveFunc();
    else
      if firstTime then
        firstTime = false;
        rslt = false;
        msg  = "Out of fuel";
      else
        return true;
      end
    end
    if not rslt and msg == "Out of fuel" then
      print("Out of fuel. please select [r]efuel or [q]uit.");
      print("(r/q)");
      local ch = read();
      if "q" == ch then
        print("Are you sure you want to stop the script?");
        print("(y/n)");
        ch = read();
        if "y" == ch then
          error("out of fuel.");
        end
      elseif "r" == ch then
        local selSlot = 1;
        while true do
          print("Please type current selected slot number.");
          ch = read();
          local num = tonumber(ch);
          if nil ~= num and 1 <= num and num <= 16 then
            selSlot = num;
            break;
          else
            print("Wrong input. Please retry.");
          end
        end
        while true do
          print("please set fuel item and type slot number.");
          print("When you finish refueling, Please type q.");
          print("FuelLevel = " .. turtle.getFuelLevel());
          ch = read();
          local num = tonumber(ch);
          if nil ~= num and 1 <= num and num <= 16 then
            turtle.select(num);
            local fRslt, fMsg = turtle.refuel();
            if not fRslt then
              print(fMsg);
            end
          elseif "q" == ch then
            turtle.select(selSlot);
            break;
          else
            print("Wrong input. Please retry.");
          end
        end
      end
    else
      return rslt, msg;
    end
  end
end
-- ---------------
-- (common) direction code
-- ---------------
DIR_FORWARD = 1
DIR_RIGHT   = 2
DIR_BACK    = 3
DIR_LEFT    = 4
DIR_NOT     = 5
-- ---------------
-- (common) turn code
-- ---------------
TURN_NOT     = 1
TURN_LEFT    = 2
TURN_RIGHT   = 3
TURN_OPPOSIT = 4
-- ---------------
-- (common) turn operation
-- ---------------
TURN_OPERATION = {
  [DIR_FORWARD] = { [TURN_LEFT] = DIR_LEFT   , [TURN_RIGHT] = DIR_RIGHT  , [TURN_OPPOSIT] = DIR_BACK    },
  [DIR_LEFT   ] = { [TURN_LEFT] = DIR_BACK   , [TURN_RIGHT] = DIR_FORWARD, [TURN_OPPOSIT] = DIR_RIGHT   },
  [DIR_RIGHT  ] = { [TURN_LEFT] = DIR_FORWARD, [TURN_RIGHT] = DIR_BACK   , [TURN_OPPOSIT] = DIR_LEFT    },
  [DIR_BACK   ] = { [TURN_LEFT] = DIR_RIGHT  , [TURN_RIGHT] = DIR_LEFT   , [TURN_OPPOSIT] = DIR_FORWARD }
}
-- ---------------
-- MyTurtle
-- ---------------
MyTurtle = {}
MyTurtle.new = function(initialY)
    local obj = {}
    obj.turtleX = 0
    obj.turtleZ = 0
    obj.turtleY = initialY
    obj.turtleDir = DIR_FORWARD
    return setmetatable(obj, {__index = MyTurtle})
  end
MyTurtle.copy = function(myTSrc)
    local obj = {}
    obj.turtleX = myTSrc.turtleX
    obj.turtleZ = myTSrc.turtleZ
    obj.turtleY = myTSrc.turtleY
    obj.turtleDir = myTSrc.turtleDir
    return setmetatable(obj, {__index = MyTurtle})
  end
MyTurtle.turnTo = function(self, direction)
    local TURN_RULES = { -- dir_forward, dir_right, dir_back, dir_left
      [DIR_FORWARD] = { TURN_NOT    , TURN_RIGHT  , TURN_OPPOSIT, TURN_LEFT    },
      [DIR_RIGHT  ] = { TURN_LEFT   , TURN_NOT    , TURN_RIGHT  , TURN_OPPOSIT },
      [DIR_BACK   ] = { TURN_OPPOSIT, TURN_LEFT   , TURN_NOT    , TURN_RIGHT   },
      [DIR_LEFT   ] = { TURN_RIGHT  , TURN_OPPOSIT, TURN_LEFT   , TURN_NOT     }}
    local turn = TURN_RULES[self.turtleDir][direction]
    if TURN_LEFT == turn then
      if not SIMULATION then
        turtle.turnLeft()
      end
    elseif TURN_RIGHT == turn then
      if not SIMULATION then
        turtle.turnRight()
      end
    elseif TURN_OPPOSIT == turn then
      if not SIMULATION then
        turtle.turnLeft()
        turtle.turnLeft()
      end
    end
    self.turtleDir = direction
  end
MyTurtle.adjustX = function(self, aimX, withDigUp, beforeEvHandlers, afterEvHandlers)
    if self.turtleX < aimX and DIR_RIGHT ~= self.turtleDir then
      self:turnTo(DIR_RIGHT)
    elseif aimX < self.turtleX and DIR_LEFT ~= self.turtleDir then
      self:turnTo(DIR_LEFT)
    end
    local function sign(val)
      if val == 0 then
        return 0
      else
        return math.abs(val) / val
      end
    end
    while self.turtleX ~= aimX do
      if not SIMULATION then
        surelyFwd()
        if withDigUp then
          surelyDigUp()
        end
      end
      self.turtleX = self.turtleX + sign(aimX - self.turtleX)
    end
  end
MyTurtle.adjustZ = function(self, aimZ, withDigUp, beforeEvHandlers, afterEvHandlers)
    if self.turtleZ < aimZ and DIR_FORWARD ~= self.turtleDir then
      self:turnTo(DIR_FORWARD)
    elseif aimZ < self.turtleZ and DIR_BACK ~= self.turtleDir then
      self:turnTo(DIR_BACK)
    end
    local function sign(val)
      if val == 0 then
        return 0
      else
        return math.abs(val) / val
      end
    end
    while self.turtleZ ~= aimZ do
      if not SIMULATION then
        surelyFwd()
        if withDigUp then
          surelyDigUp()
        end
      end
      self.turtleZ = self.turtleZ + sign(aimZ - self.turtleZ)
    end
  end
MyTurtle.moveTo = function(self, aimX, aimZ, withDigUp, beforeEvHandlers, afterEvHandlers)
    self:adjustZ(aimZ, withDigUp, beforeEvHandlers, afterEvHandlers)
    self:adjustX(aimX, withDigUp, beforeEvHandlers, afterEvHandlers)
  end
MyTurtle.backTo = function(self, aimX, aimZ, withDigUp, beforeEvHandlers, afterEvHandlers)
    self:adjustX(aimX, withDigUp, beforeEvHandlers, afterEvHandlers)
    self:adjustZ(aimZ, withDigUp, beforeEvHandlers, afterEvHandlers)
  end
MyTurtle.adjustY = function(self, aimY)
    if self.turtleY < aimY then
      while self.turtleY ~= aimY do
        surelyDigUp()
        surelyUp()
        self.turtleY = self.turtleY + 1
      end
    elseif aimY < self.turtleY then
      while self.turtleY ~= aimY do
        turtle.digDown()
        surelyDown()
        self.turtleY = self.turtleY - 1
      end
    end
  end
MyTurtle.pos = function(self)
    return { y = self.turtleY, x = self.turtleX, z = self.turtleZ }
  end