-- Remember to put a chest directly behind the turtle at it's current location.
-- It will deliver it's resources to this chest when full

-- Y Level to Branch-mine at
local BranchMineLevel = 5

-- How many blocks on the ignore list
-- that you put in the first number of slots
local IgnoreSlots = 4

-- Set this to true if it is ok for the turtle to mine strait down to the y level for the Branch mine
local MineDown = false
local TunnelLength = 100

-- Set this to false if you don't have a working GPS system
local UseGPS = false
--ALL THIS MUST BE FILLED IN IF YOU DON"T USE GPS
local StartX = 697
local StartY = 125
local StartZ = 1396
-- EX: "SOUTH", "NORTH", "EAST", "WEST"
local ForwardFacingDirection = "WEST"
--END NO GPS FILL INFORMATION



--DO NOT TOUCH ANYTHING BELOW THIS LINE
local mov = {}
local rot = {}
local dig = {}
local PositionInBranchMine = 0
local RotatePosition = "FORWARD"

local InsertedIntoLeftWall = false
local InsertedIntoRightWall = false
local InsertionAmount = 0

local XX = StartX
local YY = StartY
local ZZ = StartZ
local PrimaryAxis = ""
local SecondaryAxis = ""

local function Refuel()
        currentFuelRequired = (10 + (TunnelLength-PositionInBranchMine)*2)/40
        if turtle.getFuelLevel() < currentFuelRequired then
                turtle.select(16)
                return turtle.refuel(currentFuelRequired)
        else
                return true
        end
end


local function readLines(sPath)
  local file = fs.open(sPath, "r") -- open the file
  if file then -- check if it's open
    local tLines = {} -- table to store the lines
    local sLine = file.readLine() -- read a line from the file
    while sLine do -- while there's a line in the file
          table.insert(tLines, sLine) -- add it to the table
          sLine = file.readLine() -- get the next line
    end
    file.close() -- close the file
    return tLines -- return the table with the lines
  end
  return nil -- there was an error opening the file, return nil to let the user know
end

local function writeLines(sPath, tLines)
  local file = fs.open(sPath, "w") -- open the file
  if file then -- check if the file is open
    for _, sLine in ipairs(tLines) do -- for each line in the table
          file.writeLine(sLine) -- write the line
    end
    file.close() -- close the file
  end
end

function filereadline(filename, line)
  local tLines = readLines(filename) -- read the lines from the file (using the previous functions)
  if not tLines then -- if there was an error
    return nil -- return nil/error
  end
  return tLines[line] -- return the line
end

function filewriteline(filename, line, text)
  local tLines = readLines(filename) -- read the lines from the file (using the previous functions)
  if tLines then -- if there was no error
    tLines[line] = text -- set the line
    writeLines(filename, tLines) -- write the lines back to the file (using the previous functions)
  end
end

local function incrementCoordinates(incX,incY,incZ)
XX = XX + incX
YY = YY + incY
ZZ = ZZ + incZ
filewriteline("BranchMineData", 7, XX)
filewriteline("BranchMineData", 8, YY)
filewriteline("BranchMineData", 9, ZZ)
end

--directionInteger 0 = forward, 1 = left, 2 = backward, 3 = right, 4 = up, 5 = down
local function updateCoordinates(directionInteger)
        --Displace the direction by the current Rotation
        if directionInteger <= 3 then
                if directionInteger == 0 then
                        if string.match(RotatePosition,"LEFT") then
                                directionInteger = 1
                        elseif string.match(RotatePosition,"BACKWARD") then
                                directionInteger = 2
                        elseif string.match(RotatePosition,"RIGHT") then
                                directionInteger = 3
                        end
                elseif directionInteger == 2 then
                        if string.match(RotatePosition,"LEFT") then
                                directionInteger = 3
                        elseif string.match(RotatePosition,"BACKWARD") then
                                directionInteger = 0
                        elseif string.match(RotatePosition,"RIGHT") then
                                directionInteger = 1
                        end
                end
        end

        local incrementPrimary = true
        local incrementBy = 0
        local incrementX = 0
        local incrementY = 0
        local incrementZ = 0
        --if we are moving forward
        if directionInteger == 0 then
                incrementPrimary = true
                incrementBy = 1
        --if we are moving left
        elseif directionInteger == 1 then
                incrementPrimary = false
                incrementBy = 1
        --if we are moving backward
        elseif directionInteger == 2 then
                incrementPrimary = true
                incrementBy = -1
        --if we are moving right
        elseif directionInteger == 3 then
                incrementPrimary =false
                incrementBy = -1
        elseif directionInteger == 4 then
                incrementY = 1
        elseif directionInteger == 5 then
                incrementY = -1
        end

        if incrementPrimary then
                if PrimaryAxis == "X" then
                        incrementX = incrementBy
                elseif PrimaryAxis == "-X" then
                        incrementX = -1 * incrementBy
                elseif PrimaryAxis == "Z" then
                        incrementZ = incrementBy
                elseif PrimaryAxis == "-Z" then
                        incrementZ = -1 * incrementBy
                end
        else
                if SecondaryAxis == "X" then
                        incrementX = incrementBy
                elseif SecondaryAxis == "-X" then
                        incrementX = -1 * incrementBy
                elseif SecondaryAxis == "Z" then
                        incrementZ = incrementBy
                elseif SecondaryAxis == "-Z" then
                        incrementZ = -1 * incrementBy
                end
        end
        incrementCoordinates(incrementX,incrementY,incrementZ)
end

mov.forward = function(times)
        local boolean v = false
        for i=1,times do
                if turtle.detect() == false then
                        while not turtle.forward() do
                                Refuel()
                                sleep(1)
                        end
                        updateCoordinates(0)
                        v = true
                else
                        v = false
                        return v
                end
        end
        return v
end

mov.back = function(times)
        local boolean v = false
        for i=1,times do
                while not turtle.back() do
                        Refuel()
                        sleep(1)
                end
                updateCoordinates(2)
                v = true
        end
        return v
end

mov.up = function(times)
        local boolean v = false
        for i=1,times do
                if turtle.detectUp() == false then
                        while not turtle.up() do
                                Refuel()
                                sleep(1)
                        end
                        updateCoordinates(4)
                        v = true
                else
                        v = false
                        return v
                end
        end
        return v
end

mov.down = function(times)
        local boolean v = false
        for i=1,times do
                if turtle.detectDown() == false then
                        while not turtle.down() do
                                Refuel()
                                sleep(1)
                        end
                        updateCoordinates(5)
                        v = true
                else
                        v = false
                        return v
                end
        end
        return v
end

mov.place = function()
    while not turtle.place() do
          sleep(1)
    end
    return true
end

rot.right = function()
    while not turtle.turnRight() do
            sleep(1)
    end

        if RotatePosition == "FORWARD" then
                RotatePosition = "RIGHT"
        elseif RotatePosition == "RIGHT" then
                RotatePosition = "BACKWARD"
        elseif RotatePosition == "BACKWARD" then
                RotatePosition = "LEFT"
        elseif RotatePosition == "LEFT" then
                RotatePosition = "FORWARD"
        end
        filewriteline("BranchMineData", 5, RotatePosition)
    return true
end

rot.left = function()
    while not turtle.turnLeft() do
            sleep(1)
    end

        if RotatePosition == "FORWARD" then
                RotatePosition = "LEFT"
        elseif RotatePosition == "LEFT" then
                RotatePosition = "BACKWARD"
        elseif RotatePosition == "BACKWARD" then
                RotatePosition = "RIGHT"
        elseif RotatePosition == "RIGHT" then
                RotatePosition = "FORWARD"
        end
        filewriteline("BranchMineData", 5, RotatePosition)
    return true
end

dig.forward = function()
        if turtle.detect() then
                while not turtle.dig() do
                                sleep(1)
                end
                return true
        else
                print("No Block to mine forward")
                return false
        end
end

dig.up = function()
        if turtle.detectUp() then
                while not turtle.digUp() do
                                sleep(1)
                end
                return true
        else
                print("No Block to mine up")
                return false
        end
end

dig.down = function()
        if turtle.detectDown() then
                while not turtle.digDown() do
                                sleep(1)
                end
                return true
        else
                print("No Block to mine down")
                return false
        end
end

local function DigMoveForward()
        if mov.forward(1) == false then
                dig.forward()
                sleep(0.5)
                DigMoveForward()
        end
end

local function DigMoveUp()
        if mov.up(1) == false then
                dig.up()
                sleep(0.5)
                DigMoveUp()
        end
end

local function DigMoveDown()
        if mov.down(1) == false then
                dig.down()
                sleep(0.5)
                DigMoveDown()
        end
end

-- Begin BranchMining Code
if UseGPS then
        if rednet.open("right") == nil then
                print("You had GPS Enabled but there is not a modem on this turtle")
                return
        end
end

local function DepositChest()
        print("Depositing the Load...")
        for i = IgnoreSlots + 1,15 do
                turtle.select(i)
                turtle.drop()
        end
end

local function GetCoalChest()
        look(1) -- look left
        turtle.select(15)
        if turtle.suck() == false then
                rot.right()
                return false
        else
                if turtle.compareTo(16) then
                        turtle.transferTo(16)
                        turtle.drop()
                        rot.right()
                        return true
                else
                        turtle.drop()
                        rot.right()
                        return false
                end
        end
end

local function ReturnBack()
        local xC, yC, zC  = 0
if UseGPS then
        xC, yC, zC = gps.locate(5)
else
        xC = XX
        yC = YY
        zC = ZZ
end
look(2) -- look backward
Distance = 0
xC = tonumber(xC)
yC = tonumber(yC)
zC = tonumber(zC)
StartX = tonumber(StartX)
StartY = tonumber(StartY)
StartZ = tonumber(StartZ)
if xC < StartX then
        Distance = StartX - xC
elseif xC > StartX then
        Distance = xC - StartX
elseif zC < StartZ then
        Distance = StartZ - zC
elseif zC > StartZ then
        Distance = zC - StartZ
end

for i = 1,Distance do
        if mov.forward(1) == false then
                dig.forward()
                mov.forward(1)
        end
end
look(0) -- look forward
filewriteline("BranchMineData", 5, RotatePosition)
if UseGPS then
        xC, yC, zC = gps.locate(5)
else
        xC = XX
        yC = YY
        zC = ZZ
end
xC = tonumber(xC)
yC = tonumber(yC)
zC = tonumber(zC)
StartX = tonumber(StartX)
StartY = tonumber(StartY)
StartZ = tonumber(StartZ)
        if StartY > yC then
                mov.up(StartY - yC)
        elseif StartY < yC then
                mov.down(yC - StartY)
        end

        DepositChest()
        if GetCoalChest() == false then
                if Refuel() == false then
                        print("***Out of fuel***")
                        print("***NO FUEL IN CHEST, PROGRAM HALT***")
                        return
                else
                        print("Returning to Mine")
                        MineToMine()
                        StartMining()
                end
        else
                print("Returning to Mine")
                MineToMine()
                StartMining()
        end
end

local function Finish()
            local xC, yC, zC = 0
    if UseGPS then
            xC, yC, zC = gps.locate(5)
    else
            xC = XX
            yC = YY
            zC = ZZ
    end
    look(2) -- look Backward
    RotatePosition = "BACKWARD"
    filewriteline("BranchMineData", 5, RotatePosition)
    Distance = 0
    if xC < StartX then
            Distance = StartX - xC
    elseif xC > StartX then
            Distance = xC - StartX
    elseif zC < StartZ then
            Distance = StartZ - zC
    elseif zC > StartZ then
            Distance = zC - StartZ
    end

    for i = 1,Distance do
            if mov.forward(1) == false then
                    dig.forward()
                    mov.forward(1)
            end
    end
    look(0) -- look Forward
    RotatePosition = "FORWARD"
    filewriteline("BranchMineData", 5, RotatePosition)
    if UseGPS then
            xC, yC, zC = gps.locate(5)
    else
            xC = XX
            yC = YY
            zC = ZZ
    end

            if StartY > yC then
                    mov.up(StartY - yC)
            elseif StartY < yC then
                    mov.down(yC - StartY)
            end

            DepositChest()
            print("Finished!")
end

local function InventoryFull()
        SlotsFull = 0
        for i=1,16 do
                if turtle.getItemCount(i) > 0 then
                        SlotsFull = SlotsFull + 1
                end
        end

        if SlotsFull == 16 then
                return true;
        else
                return false;
        end
end

function StartMining()

    BlocksTillEnd = TunnelLength - PositionInBranchMine

    while BlocksTillEnd > 0 do
        if Refuel() == false then
                print("***Out of fuel***")
                ReturnBack()
                return
        end

        if InventoryFull() then
                print("***Inventory Full***")
                ReturnBack()
                return
        end

        dig.forward()
        DigMoveDown()
        DigMoveDown()
        DigMoveDown()
        DigMoveDown()

        PositionInBranchMine = PositionInBranchMine + 4
        BlocksTillEnd = TunnelLength - PositionInBranchMine
    end
    Finish()
end

local FuelCount = turtle.getItemCount(16)

if FuelCount == 0 then
        print("please put fuel in the last slot of the Turtle.")
        return
else
        if FuelCount < 10 then
                print("Please put at least 10 of the fuel you are using in the Turtle.")
                return
        end
end

Refuel()
StartMining()