local robot = require("robot")
local os = require("os")
local io = require("io")
local term = require("term")
local computer = require("computer")


--[[defines misc variables]]
programrunthrough = 0 --defines whether the program has finished filling the chunk


--[[Defines variables for inventory state]]
hasinventory = 1 --defines whether the inventory is empty or not
invsize = robot.inventorySize() -- defines the inventory size of the robot
maxe = computer.maxEnergy() - 400 --defines the max energey storage of the robot minus 400 because the robots don't always recharge 100%
thirde = maxe / 3 --defines one third of the robots energy for the purpose of delineating when the robot is low on energy

--[[Defines variables for mutliple robots and only doing part of a chunk]]
robotstartpos = 1
fillfullchunk = 1
robotstartposdefined = 0
fillfullchunkdefined = 0


--[[Defines variables for tracking movement]]
y = 0   --Longitudinal
z = 0   --Vertical
a = 0   --Lateral
facing = 1 -- The longitudinal direction the robot is facing
evena = true --defines whether 'a' variable is even or not


--[[Redefines variables for tracking movement based on robotstartpos]]
function startpostracking()
print ("startpostracking start")
 if robotstartpos == 1 then
  y = 0
  a = 1
  evena = false
 elseif robotstartpos == 2 then
  y = -1
  a = 2
  evena = true
 end
 if robotstartpos == 1 and fillfullchunk == 1 then
  maxa = 16
 elseif robotstartpos == 1 and fillfullchunk == 0 then
  maxa = 8
 elseif robotstartpos == 2 and fillfullchunk == 1 then
  mina = 1
 elseif robotstartpos == 2 and fillfullchunk == 0 then
  mina = 9
 end
end


--[[Asks for user input to define variables at the start of the program]]
function userinput()
 while robotstartposdefined == 0 do
  robotstartposfunc()
 end
 while fillfullchunkdefined == 0 do
  fillfullchunkfunc()
 end
end


function robotstartposfunc()
 term.write("Is this robot in position 1 or 2? - ")
 robotstartposinput = io.read()
 if robotstartposinput == "1" then
  robotstartpos = 1
  robotstartposdefined = 1
 elseif robotstartposinput == "2" then
  robotstartpos = 2
  robotstartposdefined = 1
 else
  robotstartposdefined = 0
  print("Invalid input")
 end
 print("position "..robotstartpos)
end


 function fillfullchunkfunc()
 term.write("How many robots are you using 1 or 2? - ")
 fillfullchunkinput = io.read()
 if fillfullchunkinput == "1" then
  fillfullchunk = 1
  fillfullchunkdefined = 1
 elseif fillfullchunkinput == "2" then
  fillfullchunk = 0
  fillfullchunkdefined = 1
 else
  fillfullchunkdefined = 0
  print("Invalid input")
 end
 print("fillfullchunk is "..fillfullchunk)
end


--[[Checks each slot until it finds one that isn't empty and then selects it. if all slots are empty it changes 'hasinventory' state to 0]]

function slotselect()
print ("slotselect start")
 print ("inventory size is "..invsize)
 slot = 1
 while slot < invsize do
  if robot.count(slot) > 0 then
   robot.select(slot)
   print ("selecting slot "..slot)
   break
   else
   slot = slot + 1
   slotc = slot - 1
   print (slotc.." empty checking slot "..slot)
  end
 end
 if slot == invsize and robot.count(slot) > 0 then
  robot.select(slot)
  print ("selecting slot "..slot)
 elseif slot == invsize and robot.count(slot) == 0 then
  print ("Inventory Empty")
  hasinventory = 0
print ("slotselect to returntostart")
  returntostart()
 end
 if computer.energy() <= thirde then
   print ("Low on energy")
  hasinventory = 0
print ("slotselect to returntostart")
  returntostart()
 end
end


--[[Checks current inventory slot for items then either places one or starts the selectslot function]]
function placed()
print ("placed start")
 if robot.count() > 0 and computer.energy() > thirde then
  robot.placeDown()
 else
  print ("placed to slotselect")
  slotselect()
 end
end


--[[Moves the robot forward]]
function forwardo()
print ("forwardo start")
 if robot.detect() == false then
  robot.forward()
  y = y + 1
 else
  print ("I'm Blocked!")
 end
end


function righto()
print ("righto start")
 if robot.detect() == false then
  robot.forward()
  a = a + 1
  evena = not evena
  print ("a is "..a)
  print ("evena is "..tostring (evena))
 else
  print ("I'm Blocked!")
 end
end


--[[Moves the robot backward]]
function backwardo()
print ("backwardo start")
 if robot.detect() == false then
  robot.forward()
  y = y - 1
 else
  print ("I'm Blocked!")
 end
end


--[[Fills in all empty blocks below robot (robot nerd pole)]]
function nerdpole()
print ("nerdpole start")
 while true do
  if robot.detectDown() == false and hasinventory == 1 then
   robot.down()
   z = z + 1
  elseif robot.detectDown() == true and hasinventory == 1 then
   robot.up()
   z = z - 1
   print ("nerdpole to placed")
   placed()
  else
   print ("nerdpole break")
  break
  end
  if z <= 0 then
   print ("nerdpole z axis break")
  break
  end
 end
end


--[[Fills in a line of 16 blocks up to the floor height of the robot]]
function fillforward()
print ("fillforward start")
 while true do
  if robot.detectDown() == true and y < 16 and hasinventory == 1 then
   print ("fillforward to forwardo")
   forwardo()
   print ("Forward 1")
   print (y)
  elseif y == 16 and robot.detectDown() == true then
  break
  elseif y == 16 and robot.detectDown() == false then
   print ("fillforward to nerdpole")
   nerdpole()
  break
  elseif hasinventory == 0 then
   print ("fillfoward break")
  break
  else
   print ("Nerdpole!")
   nerdpole()
  end
 end
end


--[[Fills in a line of 16 blocks up to the floor height of the robot but goes backwards instead of forwards]]
function fillbackward()
print ("fillbackward start")
 while true do
   if robot.detectDown() == true and y > 1 and hasinventory == 1 then
    print ("fillbackward to backwardo")
    backwardo()
    print ("backward 1")
    print (y)
   elseif y == 1 and robot.detectDown() == true then
   break
   elseif y == 1 and robot.detectDown() == false then
   print ("fillbackward to nerdpole")
    nerdpole()
   break
   elseif hasinventory == 0 then
    print ("fillbackward break")
   break
   else
    print ("Nerdpole!")
    nerdpole()
   end
 end
end


--[[Moves the robot to its right by one line facing -y]]
function latright()
print ("latright start")
 if hasinventory == 1 then
  robot.turnRight()
  robot.forward()
  robot.turnRight()
  evena = not evena
  print ("evena = "..tostring (evena))
  if robotstartpos == 1 then
   facing = 0
   a = a + 1
   print ("Robot 1 at A "..a)
  elseif robotstartpos == 2 then
   facing = 1
   a = a - 1
   print ("Robot 2 at A "..a)
  end
 else
 end
end


--[[Moves the robot to its left by one line facing +y]]
function latleft()
print ("latleft start")
 if hasinventory == 1 then
  robot.turnLeft()
  robot.forward()
  robot.turnLeft()
  evena = not evena
  print ("evena = "..tostring (evena))
  if robotstartpos == 1 then
   facing = 1
   a = a + 1
   print ("Robot 1 at A "..a)
  elseif robotstartpos == 2 then
   facing = 0
   a = a - 1
   print ("Robot 2 at A "..a)
  end
 else
 end
end


--[[Turns robot towards start on longitudinal axis]]
function turntostart()
print ("turntostart start")
 if facing == 1 then
  robot.turnAround()
  facing = 0
 else
 end
end


--[[Robot returns to start]]
function returntostart()
print ("returntostart start")
 print ("returntostart to turntostart")
 turntostart()
  if robotstartpos == 1 then
   yb = y
   ab = a - 1
  elseif robotstartpos == 2 then
   yb = y + 1
   ab = a - 2
  end
  for zback = 1, z do
   robot.up()
   z = z - 1
  end
   for yback = 1, yb do
    robot.forward()
    y = y - 1
   end
 robot.turnRight()
  for aback = 1, ab do
   robot.forward()
   a = a - 1
  end
  if programrunthrough == 0 then
   refill()
   print ("returntostart to refill")
  elseif programrunthrough == 1 then
  print ("robot has finished")
  end
end


 --[[Moves the robot from start position to the chunk]]
function movetochunk()
print ("movetochunk start")
 if robotstartpos == 1 then
  robot.turnRight()
 print("movetochunk to forwardo")
  forwardo()
 elseif robotstartpos == 2 then
  robot.turnAround()
  while a < 16 do
   righto()
   evena = not evena
  end
  robot.turnLeft()
  while y < 1 do
   print("movetochunk to forwardo")
   forwardo()
  end
 end
 print("movetochunk to fillchunk")
 fillchunk()
end


--[[refills the robots inventory and pauses to charge]]
function refill()
print ("refill start")
 for fill = 1, invsize do
 robot.suckUp()
 end
 while computer.energy() < maxe do
  os.sleep(5)
  end
 if robot.count(1) > 0 then
  hasinventory = 1
  robot.select(1)
  print ("refill to movetochunk")
  movetochunk()
 else
  print ("Refill station empty")
 end
end

--[[Tells the robot which lines to fill]]
function fillchunk()
print("fillchunk start")
 if robotstartpos == 1 and y == 1 and a == 1 and z == 0 then
  print("fillchunk to fillpos1")
  fillpos1()
 elseif robotstartpos == 2 and y == 1 and a == 16 and z == 0 then
  print("fillchunk to fillpos2")
  fillpos2()
 else
 print ("out of position to fillchunk")
 end
end


--[[Fills out the defined area from in chunk position1]]
function fillpos1()
print ("fillpost1 start")
 while true do
  if hasinventory == 1 and a < maxa and evena == false then
   print ("from fillpos1 to fillforward")
   fillforward()
   print ("from fillpos1 to latright")
   latright()
  elseif hasinventory == 1 and a < maxa and evena == true then
   print ("from fillpos1 to fillbackward")
   fillbackward()
   print ("from fillpos1 to latleft")
   latleft()
  elseif hasinventory == 1 and a == maxa and y > 1 then
  print ("from fillpos1 to fillbackward y < 1")
   fillbackward()
  elseif hasinventory == 1 and a == maxa and y == 1 then
   if robot.detectDown() == false then
   print ("from fillpos1 to nerdpole")
   nerdpole()
   else
   programrunthrough = 1
   print ("robot has finished returning to start")
   returntostart()
   break
   end
  elseif hasinventory == 0 then
   print ("fillpos1 inv break")
   break
  end
 end
end


--[[Fills out the defined area from in chunk position2]]
function fillpos2()
print ("fillpost2 start")
 while true do
  if hasinventory == 1 and a > mina and evena == true then
   print ("from fillpos2 to fillforward")
   fillforward()
   print ("from fillpos2 to latright")
   latleft()
   print ("from fillpos2 to latleft")
  elseif hasinventory == 1 and a > mina and evena == false then
   fillbackward()
   print ("from fillpos2 to fillbackward")
   latright()
  elseif hasinventory == 1 and a == mina and y > 1 then
  print ("from fillpos2 to fillbackward y > 1")
   fillbackward()
  elseif hasinventory == 1 and a == mina and y == 1 then
   if robot.detectDown() == false then
   print ("from fillpos2 to nerdpole")
   nerdpole()
   else
   programrunthrough = 1
   print ("robot has finished returning to start")
   returntostart()
   break
   end
  elseif hasinventory == 0 then
   print ("fillpos2 inv break")
   break
  end
 end
end


print ("main to userinput")
userinput()
print ("main to startpostracking")
startpostracking()
print ("main to refill")
refill()