tunnelQuarry

local tArgs = {...} --command line arguments table
local resetPos = {} --table of arguments to set the persist values
local prevPos = {} --table to hold the loaded saved previous values
local height = tArgs[1] or prevHeight --sets height to equal, in order of precedence, tArgs[1] or prevHeight
local width = tArgs[2] or prevWidth --sets width to equal, in order of precedence, tArgs[2] or prevWidth
local depth = tArgs[3] or prevDepth --sets depth to equal, in order of precedence, tArgs[3] or prevDepth
local prevHeight = prevPos[2] or 0 --sets the prevHeight equal to prevPos[2], but if it cant then it sets it equal to 0
local prevWidth = prevPos[1] or 0 --same
local prevDepth = prevPos[3] or 0 --same
local persist = prevPos[4] or false --same except false.
local currHeight = 0 --sets a changeable variable to 0 for saving
local currWidth = 0 --sets a changeable variable to 0 for saving
local currDepth = 0 --sets a changeable variable to 0 for saving
local resetHeight = resetPos[2] or 0 --adjusts
local resetWidth = resetPos[1] or 0
local resetDepth = resetPos[3] or 0
local m=0 --makes a multipurpose variable
fs.makeDir("prevPos")
fs.makeDir("resetPos")

function loadPrev()
    local w = fs.open("prevPos/prevWidth","r")
    local h = fs.open("prevPos/prevHeight","r")
    local d = fs.open("prevPos/prevDepth","r")
        table.insert(prevPos,w)
        table.insert(prevPos,h)
        table.insert(prevPos,d)
    w.close()
    h.close()
    d.close()
end

function checkPersist()
    local p = fs.open("resetPos/persist","r")
    if p == nil then
        local pw = fs.open("resetPos/persist","w")
        if pw ~= nil then
            pw.write(persist)
            pw.close()
        end
    elseif p ~= nil then
        table.insert(prevPos,p)
        p.close()
    end
end

function forward() --makes a persistant forward function in case of gravel/sand/mob/player
    while turtle.forward() == false do --keeps looping if it can't move forward, stops when it does succesfully.
        if turtle.detect() then --detects for a block as obstruction
            turtle.dig()  -- breaks block if detected
        else
            turtle.attack() --else attacks to move mob/player
        end
    end
    refuel() --checks if turtle needs fuel, fuels if needed
end

function moveRight() --moves turtle right one
    turtle.turnRight()
    forward()
    turtle.turnLeft()
end

function moveLeft() -- moves turtle left one
    turtle.turnLeft()
    forward()
    turtle.turnRight()
end

function up() --makes a persistant up function in case of gravel/sand/mob/player
    while turtle.up() == false do --loops to move up until succesful
        if turtle.detectUp() == true then --if block in the way
            turtle.digUp() --breaks it
        else --if mob/player is in the way
            turtle.attackUp() --attacks to move it
        end
    end
end

function down() -- persistant down function
    while turtle.down() == false do
        if turtle.detectDown() == true then
            turtle.digDown()
        else
            turtle.attack()
        end
    end
end

function digRow() --makes function to dig a row. saves turtle position in row. allows session persistance
local w = fs.open("prevPos/prevWidth","w") --opens width save file for writing
    for i=1,math.abs(resetWidth-width)-1 do --loop to dig row. reacts for session persistance
        turtle.dig()
        if m==0 then --if it last moved left will move right
            moveRight()
            currWidth = currWidth+1 --currWidth increases towards right
        elseif m==1 then --if last moved right will move left
            moveLeft()
            currWidth = currWidth-1 --currWidth decreases towards left
        end
        checkInv()
        w.write(currWidth) --writes currWidth to width save file
    w.close() --closes width save file
    end
    turtle.dig() --breaks the last block in the row without possibly moving too far
    resetWidth=0
end

function nextRow() --function to move turtle up to the next row. saves turtle height. allows session persistence
local h = fs.open("prevPos/prevHeight","w") --opens height save file for writing
    for i=1,math.abs(resetHeight-height)-1 do --loop to dig 1 depth  of tunnel
        digRow() --initiates the digRow function
        if m==0 then
            m=1
        elseif m==1 then
            m=0
        end
        up() --when digRow is done moves turtle up to next row
        currHeight = currHeight+1 --currHeight increases going up
        h.write(currHeight) --writes currHeight to height save file
        h.close() --closes height save file
    end
    digRow()
    if m==0 then
        m=1
    elseif m==1 then
        m=0
    end
    resetHeight=0
end

function tunnel() --function to move the turtle deeper into tunnel. saves depth. allows session persistence
local d = fs.open("prevPos/prevDepth","w") --opens depth save file for writing
    persist = true
    for i=1,math.abs(resetDepth-depth)-1 do --loop to dig tunnel
        nextRow() --initiates the function nextRow
        resetTurtlePos()
        forward()
        currDepth = currDepth+1 --currDepth increases further into tunnel
        d.write(currDepth) --writes currDepth to depth save file
        d.close() --closes depth save file.
    end
    nextRow() --digs final depth of tunnel
    resetTurtlePos()
    turtle.turnRight()
    turtle.turnRight()
    for i=1,math.abs(resetDepth-depth) do
        forward()
    end
    resetDepth=0
end

function resetTurtlePos() --function to reset the turtle so that the tunnel is straight. saves width and height. allows session persistence
local h = fs.open("prevPos/prevHeight","w") --opens height save file for writing
local w = fs.open("prevPos/prevWidth","w") --opens width save file for writing
    if m==1 then --if it just moved right
        for i=1,math.abs(resetHeight-height)-1 do --moves down, session persistence
            down()
            currHeight = currHeight-1 --currHeight decreases as move down
            h.write(currHeight) --writes currHeight to height save file
            h.close() --closes height save file
        end
        turtle.turnLeft()
        for i=1,math.abs(resetWidth-width)-1 do --moves left, session persistence
            forward()
            currWidth = currWidth-1 --currWidth decreases as move left
            w.write(currWidth) --writes currWidth to width save file
            w.close() --closes width save file
        end
        turtle.turnRight()
    elseif m==0 then --if it just moved left
        for i=1,math.abs(resetHeight-height) do --moves down, session persistence
            turtle.down()
            currHeight = currHeight-1 --currHeight decreases as move down
            h.write(currHeight) --write currHeight to height save file
            h.close() --closes height save file
        end
    end
    m=0
end


function cleanUp() --cleans inventory
    turtle.select(16) --selects enderchest
    turtle.turnRight()
    turtle.turnRight() --turns around
    turtle.place() --places enderchest
    for i=1,14 do --selects each slot 1 through 14 and drops items into enderchest
        turtle.select(i)
        turtle.drop()
    end
end

function checkInv() -- checks if cleanUp needs to happen
    if turtle.getItemCount(14) ~= 0 then --checks last possibly available inventory slot
        cleanUp() --runs cleanUp if inventory is full
    end
end

function refuel() --checks if turtle needs fuel
    if turtle.getFuelLevel() <400 then --if turtle has less than 400 fuel
        turtle.select(15) --turtle selects coal
        turtle.refuel(4) --refuels with 4
        turtle.select(1) --selects slot 1 again
    end
end

function sessionPersistence() --allows for session persistence in this program
    if resetTurtle == true then
        local w = fs.open("prevPos/prevWidth","w")
        local h = fs.open("prevPos/prevHeight","w")
        local d = fs.open("prevPos/prevDepth","w")
        local p = fs.open("prevPos/persist","w")
            w.write(nil)
            h.write(nil)
            d.write(nil)
            p.write(nil)
        w.close()
        h.close()
        d.close()
        p.close()
    elseif resetTurtle == false then
        loadPrev()

    end
local w = fs.open("prevPos/prevWidth","r") --opens width save file for reading
local h = fs.open("prevPos/prevHeight","r") --opens height save file for reading
local d = fs.open("prevPos/prevDepth","r") --opens depth save file for reading
    table.insert(resetPos,w) --sets data from prevPos/prevWidth to the table resetPos in slot [1]
    table.insert(resetPos,h) --sets data from prevPos/prevHeight to the table resetPos in slot [2]
    table.insert(resetPos,d) --sets data from prevPos/prevDepth to the table resetPos in slot [3]
    if w~=nil and h~=nil and d~=nil then
        w.close()
        h.close()
        d.close()
    end
end

function run()
    checkPersist()
    if persist == true then
        print("Would you like to reset this program's persistence? true/false: ")
        local resetTurtle = read()
    end
    sessionPersistence()
    tunnel()
end

run()