minecraft swarm drone

--y = 6+3   -- y level

function estFuel(f,r,y)
    fuel = 8*f+2*r+2*y+2
    print("refueling to estimated level of "..fuel)
    turtle.select(1)
    while turtle.getFuelLevel() < fuel do
        if turtle.getItemCount(1) < 1 then
            if not turtle.suckDown() then
                print("can't find fuel in there")
                sleep(2)
            end
        end
        turtle.refuel(1)
        print("fuel level: "..turtle.getFuelLevel().." / "..fuel)
    end
    turtle.dropDown()
end

function tleft(turns)
    if turns == nil then
        turns = 1
    end
    for i = 1,turns do
        turtle.turnLeft()
    end
end

function tright(turns)
    if turns == nil then
        turns = 1
    end
    for i = 1,turns do
        turtle.turnRight()
    end
end

function move(dir, dist, dig)
    for d = 1, dist do
        if dir == "f" then
            while not turtle.forward() do
                if turtle.detect() then
                    if (not peripheral.isPresent("front")) and dig then
                        turtle.dig()
                    end
                else
                    turtle.attack()
                end
                sleep(0.2)
            end
        elseif dir == "u" then
            while turtle.detect() and dig do
                turtle.dig()
                sleep(0.2)  -- wait for gravel/sand to settle
            end
            while not turtle.up() do
                if turtle.detectUp() then
                    if not peripheral.isPresent("top") then
                        turtle.digUp()
                    end
                else
                    turtle.attackUp()
                end
                sleep(0.2)
            end
        elseif dir == "d" then
            while turtle.detect() and dig do
                turtle.dig()
                sleep(0.2)
            end
            while not turtle.down() do
                if turtle.detectDown() then
                    if not peripheral.isPresent("bottom") then
                        turtle.digDown()
                    end
                else
                    turtle.attackDown()
                end
            end
        elseif dir == "b" then
            if not turtle.back() then
                tleft(2)
                while not turtle.forward() do
                    if turtle.detect() then
                        if not peripheral.isPresent("front") then
                            turtle.dig()
                        end
                    else
                        turtle.attack()
                    end
                end
                tleft(2)
            end
        end
    end
end

-- read position from file
fh = fs.open("disk/state","r")
right = tonumber(fh.readLine())
forward = tonumber(fh.readLine())
y = tonumber(fh.readLine())
fh.close()

-- update position to file
fh = fs.open("disk/state","w")
newRight = right - 1
newForward = forward
if newRight == -1 then
    newRight = 15
    newForward = forward - 1
end
if newForward == -1 then
    newForward = 3
end
fh.writeLine(newRight)
fh.writeLine(newForward)
fh.writeLine(y)
fh.close()

-- refuel
estFuel(forward, right, y)

-- position
if right == 15 then
    dig = true
else
    -- dig = false
    dig = true
end
if forward > 0 then
    move("f",4*forward-1,dig)
    tright()
    move("f",right,dig)
    tleft()
elseif (forward == 0) and (right == 0) then
    move("f",1,true)
    move("d",2,true)
    move("b",2,true)
else
    tright()
    move("f",right,dig)
    tright()
    move("f",1,true)
    tleft(2)
end

-- dig out
if (forward == 0) and (right == 0) then
    move("d",y-7,true)
else
    move("d",y-5,true)
end
move("f",2,true)
-- move("u",y-6,true)
-- move("u",1,false)
move("u",y-5,true)
-- return
-- if forward == 0 then
    -- move("f",1,false)
-- end
tleft()
move("f",right,false)
tleft()
move("f",4*forward+1,false)

-- dump inventory
print("dumping")
for s=16,1,-1 do
    if turtle.getItemCount(s) > 0 then
        turtle.select(s)
        while not turtle.dropDown() do
            sleep(0.5)
        end
    end
end
redstone.setOutput("front",true)