ValuableFinderv2

depth = 0
descending = true
ascending = true
chestSlot = 1

function fuel()
    if turtle.getFuelLevel() <= 10 then
        local fuelTable = {"minecraft:coal", "minecraft:lava_bucket"}
        for i = 1, 16, 1 do
            local itemData = turtle.getItemDetail(i)
            for k, v in ipairs(fuelTable) do
                if itemData.name == v then
                    turtle.select(i)
                    turtle.refuel()
                    turtle.select(1)
                end
            end
        end
    end
end

function isValuable()
    local junkTable = {"minecraft:stone", "minecraft:dirt", "minecraft:gravel", "minecraft:sand", "minecraft:torch"}
    local valuable = true

    local isBlock, blockData = turtle.inspect()
        if isBlock == true then
            print("There's something here. Block data:")
            print(blockData.name)
            print(blockData.metadata)
            for k, v in ipairs(junkTable) do
                if blockData.name == v then
                    print("This is junk.")
                    valuable = false
                    break
                end
            end
        else
            print("There isn't anything here.")
            valuable = false
        end
    if valuable then
        print("There's something valuable here!")
        return true

    else
        print("Nothing interesting here. Moving on")
        return false
    end
end

function checkSides()
    for i = 0, 3, 1 do
        if isValuable() then
            turtle.dig()
        end
        turtle.turnRight()
    end
end

function isBottomEmpty()
    local isBlock, blockData = turtle.inspect()
    if isBlock then
        return true
    else
        return false
    end
end

function isBottomBedrock()
    local isBlock, blockData = turtle.inspectDown()
    if isBlock then
        if blockData.name == "minecraft:bedrock" then
            print("We've hit bedrock!")
            return true
        else
            return false
        end
    else
        return false
    end
end

function knightMove()
    if turtle.detect()
        turtle.dig()
    end
    turtle.forward()
    if turtle.detect()
        turtle.dig()
    end
    turtle.forward()

    turtle.turnRight()

    if turtle.detect()
        turtle.dig()
    end
    turtle.forward()
end

function chestInInventory()
    local foundChest = false
    for i = 1, 16, 1 do
        local data = getItemDetail(i)
        if data.name == "minecraft:chest" then
            foundChest = true
        end
    end

    if foundChest then
        return true
    else
        return false
    end
end

function returnToSurface()
    print("Let's go back up...")

    while depth ~= 0 do
        fuel()
        if turtle.up() then
            depth = depth - 1
        else
            print("Obstruction detected...")
            turtle.digUp()
        end
    end
end

print("Checking for chests")
if not chestInInventory then
    print("No chests found! Continue anyway?")
    print("Y for yes, anything else for no")

    local decision = io.read()
    if decision ~= "y" then
        os.exit()
    end
end

print("Let's go!")


while descending do
    fuel()
    checkSides()

    if isBottomBedrock() then
        descending = false
        break
    end

    turtle.digDown()
    turtle.down()
    depth = depth + 1
end

knightMove()

print("Let's go back up...")

while ascending do
    fuel()
    checkSides()

    if (depth = 0)
        ascending = false
        break
    end

    turtle.digUp()
    if turtle.up() then
        depth = depth - 1
    else
        print("Obstruction detected...")
        turtle.digUp()
    end
    depth = depth - 1
end

print("Chest dumping")
turtle.select(16)
turtle.placeDown()
for a = 1, 14 do
    turtle.select(a)
    turtle.dropDown()
end
if turtle.getItemCount(16) < 0 then
    print("Out of chests!! Stopping")
    break
end
turtle.select(1)

print("Done!")