mine.lua

tunnelLength = 10
buffer = 2
tunnels = 10
placeTorches = true
autoRefuel = true

trash = {
    dirt = true,
    cobblestone = true,
    gravel = true,
    granite = true,
    andesite = true,
    diorite = true
}

desiredOres = {
    "minecraft:coal_ore",
    "minecraft:diamond_ore",
    "minecraft:gold_ore"
}

up = true

local function check()
    for i=2,15 do
        item = turtle.getItemDetail(i)
        if item ~= nil then
            print("Item: "..item.name)
            print(trash[item.name])

            colon = string.find(item.name, ":")

            if trash[string.sub(item.name, colon + 1)] ~= nil and item.count == 16 then
                print("That's trash, throw it out")
                turtle.select(i)
                turtle.turnLeft()
                turtle.turnLeft()
                turtle.drop()
                turtle.turnLeft()
                turtle.turnLeft()
            elseif item.name == "minecraft:coal" and autoRefuel then
                turtle.transferTo(1, turtle.getItemCount(1) - 64)

                if turtle.getFuelLevel() < 50 then
                    turtle.select(1)
                    turtle.refuel()
                end
            end
        end
    end

    os.setComputerLabel("Fuel: "..turtle.getFuelLevel())
end

local function height()
    turtle.dig()
    turtle.digUp()
    turtle.digDown()

    check()
end

local function length()
    for i=1,tunnelLength do
        height()

        if i % 5 == 0 and placeTorches then
            turtle.select(16)
            turtle.placeDown()
            turtle.select(2)
        end
        turtle.forward()
    end
end

wentLength = true

local function main()
    for k=1,tunnels do
        length()

        if wentLength then
            turtle.turnLeft()
        else
            turtle.turnRight()
        end

        for k=1,buffer + 1 do
            height()
            turtle.forward()
        end

        if wentLength then
            turtle.turnLeft()
            wentLength = false
        else
            turtle.turnRight()
            wentLength = true
        end
    end
end

main()