Branch

-- Utility functions --
function sign(x)
    if x > 0 then
        return 1
    elseif x < 0 then
        return -1
    else
        return 0
    end
end

function containsValue (tab, val)
    for index, value in ipairs(tab) do
        if value == val then
            return true
        end
    end

    return false
end

-- Safe Movement Methods --
function forward()
    while t.detect() do t.dig() end
    while not t.forward() do t.attack() end

    if w == 0 then
        x = x + 1           -- 0 is +x (east)
    elseif w == 1 then
        z = z + 1           -- 1 is +z (south)
    elseif w == 2 then
        x = x - 1           -- 2 is -x (west)
    elseif w == 3 then
        z = z - 1           -- 3 is -z (north)
    end
end

function back()
    while not t.back() do t.attack() end

    if w == 0 then
        x = x - 1           -- 0 is +x (east)
    elseif w == 1 then
        z = z - 1           -- 1 is +z (south)
    elseif w == 2 then
        x = x + 1           -- 2 is -x (west)
    elseif w == 3 then
        z = z + 1           -- 3 is -z (north)
    end
end

function up()
    while t.detectUp() do t.digUp() end
    z = z + 1
    while not t.up() do t.attackUp() end
    updateSave()
end

function down()
    while t.detectDown() do t.digDown() end
    z = z - 1
    while not t.down() do t.attackDown() end
    updateSave()
end

function turnLeft()
    t.turnLeft()
    w = (w-1) % 4
end

function turnRight()
    t.turnRight()
    w = (w+1) % 4
end

function turnTo(a)
    if a == (w-1) % 4 then
        turnLeft()
    else
        while w ~= a do
            turnRight()
        end
    end
end

function goTo(a, b, c)
    -- Y
    while y < b do up() end
    while y > b do down() end

    -- X
    if a > x then
        turnTo(0)
        while a > x do forward() end
    elseif a < x then
        turnTo(2)
        while a < x do forward() end
    end

    -- Z
    if c > z then
        turnTo(1)
        while c > z do forward() end
    elseif c < z then
        turnTo(3)
        while c < z do forward() end
    end
end

function selfOrient()
    a, c, b = gps.locate()
    forward()
    x, y, z = gps.locate()

    a = x - a
    b = z - b
    print(a,b)

    if a == 1 then
        w = 0               -- 0 is +x (east)
    elseif b == 1 then
        w = 1               -- 1 is +z (south)
    elseif a == -1 then
        w = 2               -- 2 is -x (west)
    else
        w = 3               -- 3 is -z (north)
    end

    back()
    x, y, z = gps.locate()
    print(string.format("Location:%s, %s, %s, %s", x, y, z, w))
end

-- Inventory Functions
function findInInven(ID)
    data = t.getItemDetail()
    if data then
        if data.name == ID then
            return true
        end
    end

    for i = 1,16 do
        t.select(i)
        data = t.getItemDetail()
        if data then
            if data.name == ID then
                return true
            end
        end
    end
    return false
end

function checkFuel()
    if t.getFuelLevel() < 200 * 2.5 then
        findInInven("minecraft:coal")
    end
end

-- Mining Operation Functions --
function branch(s)
    for i = 1,s do                  -- Go down along the bottom, placing floor blocks as needed
        forward()
        checkSurround()

        if not t.detectDown() then
            if findInInven("minecraft:cobblestone") then
                t.placeDown()
            end
            if findInInven("minecraft:stone") then
                t.placeDown()
            end
        end
    end

    up(); turnLeft(); turnLeft()    -- Turn around at the end
    for i = s,2,-1 do               -- Come back along the top, placing torches every 10 blocks
        if i%10 == 0 then
            if findInInven("minecraft:torch") then
                t.placeDown()
            end
        end

        forward()
        checkSurround()
    end
    down(); forward();
end

function checkSurround() -- This is recursive and will recursivly mine any ore veins that it detects
    for i = 1,4 do
        checkForward()
        turnLeft()
    end
    checkUp()
    checkDown()
end

function checkUp()
    success, data = t.inspectUp()
    if success and not containsValue(unwantedBlocks, data.name) then
        s = string.format("%s:%s:%s", x, y+1, z)
        table.insert(flaggedBlocks, s)

        up()
        checkSurround()
        down()
    end
end

function checkDown()
    success, data = t.inspectDown()
    if success and not containsValue(unwantedBlocks, data.name) then
        s = string.format("%s:%s:%s", x, y-1, z)
        table.insert(flaggedBlocks, s)

        down()
        checkSurround()
        up()
    end
end

function checkForward()
    success, data = t.inspect()
    if success and not containsValue(unwantedBlocks, data.name) then
        if w == 0 then
            s = string.format("%s:%s:%s", x+1, y, z)    -- 0 is +x (east)
        elseif w == 1 then
            s = string.format("%s:%s:%s", x, y, z+1)    -- 1 is +z (south)
        elseif w == 2 then
            s = string.format("%s:%s:%s", x-1, y, z)    -- 2 is -x (west)
        elseif w == 3 then
            s = string.format("%s:%s:%s", x, y, z-1)    -- 3 is -z (north)
        end

        table.insert(flaggedBlocks, s)

        forward()
        checkSurround()
        back()
    end
end

-- Savefile Funcitons --
function updateSave()

end



-- Main Loop
t = turtle
unwantedBlocks = {"minecraft:dirt", "minecraft:grass" , "minecraft:stone", "minecraft:cobblestone", "minecraft:sand", "minecraft:gravel", "minecraft:mossy_cobblestone", "minecraft:bedrock", "minecraft:netherrack", "minecraft:soul_sand", "minecraft:torch"}
fuels = {"minecraft:coal", "minecraft:coal_block", "minecraft:lava_bucket"}
flaggedBlocks = {}
x, y, z, w = 0, 0, 0, 0
selfOrient()

home = {x, y, z}
homeDirection = w
completeBranches = 0

while true do
    for i = 1,3 do
        forward()
        while t.detectUp() do t.digUp() end
        if not t.detectDown() then
            if findInInven("minecraft:cobblestone") then
                t.placeDown()
            end
            if findInInven("minecraft:stone") then
                t.placeDown()
            end
        end
    end
    turnLeft()
    branch(10)
    completeBranches = completeBranches + 1
    branch(10)
    completeBranches = completeBranches + 1
    turnRight()
end