--rednet.open("right")
 
--GLOBAL VARIABLES--
 
fuelSlot = 1
stoneSlot = 2
dirtSlot = 3
gravelSlot = 4
cobbleSlot = 5
home = tonumber(0)
north = 0
east = 1
south = 2
west = 3
t = tonumber(0)

--REDNET FUNCTIONS--
 
function report(msg)
    --rednet.open("right")
    clear()
    --rednet.broadcast(tostring(msg))
    print(msg)
end
 
--FILING FUNCTIONS--
 
function getLoc()
    if fs.exists("loc") then
        data = fs.open("loc", "r")
        x = tonumber(data.readLine())
        y = tonumber(data.readLine())
        z = tonumber(data.readLine())
        h = tonumber(data.readLine())
        b = tonumber(data.readLine())
        tl = tonumber(data.readLine())
        bl = tonumber(data.readLine())
        data.close()
    else
        x = 0
        y = 0
        z = 0
        h = 0
        b = 0
        tl = 0
        bl = 0
        startup()
    end
end

function getTempLoc()
        data = fs.open("tempLoc", "r")
        tgtx = tonumber(data.readLine())
        tgty = tonumber(data.readLine())
        tgtz = tonumber(data.readLine())
        tgth = tonumber(data.readLine())
        data.close()
end

function dumpLoc()
    if fs.exists("loc") then
        fs.delete("loc")
    end
    report("Opening LOC data file.")
    data = fs.open("loc", "w")
    data.writeLine(tostring(x))
    data.writeLine(tostring(y))
    data.writeLine(tostring(z))
    data.writeLine(tostring(h))
    data.writeLine(tostring(b))
    data.writeLine(tostring(tl))
    data.writeLine(tostring(bl))
    data.close()
    report("New LOC data written to file.")
end

function dumpTempLoc()
        report("Opening temporary LOC data file.")
        data = fs.open("tempLoc", "w")
        data.writeLine(tostring(x))
        data.writeLine(tostring(y))
        data.writeLine(tostring(z))
        data.writeLine(tostring(h))
        data.close()
        report("New LOC data written to file.")
end

--MOVEMENT FUNCTIONS--

function refuel(reqFuel)
    if reqFuel == nil then
        reqFuel = 80
    end
    fuel = turtle.getFuelLevel()
    while fuel < reqFuel do
        if turtle.getItemCount(fuelSlot) == 0 then
            goHome()
            goBack()
            break
        else
            turtle.refuel(1)
            fuel = turtle.getFuelLevel()
        end
    end
end

function fd()
    getLoc()
    refuel()
    if turtle.forward() then
        if h == 0 then
             x = x + 1
        elseif h == 1 then
             z = z + 1
        elseif h == 2 then
             x = x - 1
        elseif h == 3 then
             z = z - 1
        end
        report("Moving.")
    else
        report("Blocked")
    end
    dumpLoc()
end

function up()
    getLoc()
    refuel()
    if turtle.up() then
        y = y + 1
        report("Moving up.")
    else
        report("Blocked")
    end
    dumpLoc()
end

function dn()
    getLoc()
    refuel()
    if turtle.down() then
        y = y - 1
        report("Moving down.")
    else
        report("Blocked")
    end
    dumpLoc()
end

function rt()
    getLoc()
    report("Turning.")
    turtle.turnRight()
    report("Updating data file.")
    h = (h + 1) % 4
    dumpLoc()
end

function lt()
    getLoc()
    turtle.turnLeft()
    h = (h - 1) % 4
    while h < 0 do
        h = h + 4
    end
    dumpLoc()
end

function dig()
    turtle.dig()
end
        
function digUp()
    turtle.digUp()
end
        
function digDn()
    turtle.digDown()
end

--ADVANCED MOVEMENT FUNCTIONS--

function checkStuck()
    getLoc()
    dumpTempLoc()
    digFd()
    if x == tarx and z == tarz then
        face(south)
        digFd()
        digFd()
        digFd()
        goHome()
    end
end

function gofd(dist)
    if dist == nil then
        fd()
    else
        while dist > 0 do
            fd()
            dist = dist - 1
        end
    end
end

function face(tar)
    getLoc()
    while true do
        if tar == h then
            break
        else
            getLoc()
            rt()
            dumpLoc()
            report("Turning. "..tostring(h))
        end
    end
end

function findX(pos)
    getLoc()
    if x > pos then
        face(south)
        while x > pos do
            fd()
            getLoc()
        end
    elseif x < pos then
        face(north)
        while x < pos do
            fd()
            getLoc()
        end
    else
    end
end

function findZ(pos)
    getLoc()
    if z > pos then
        face(west)
        while z > pos do
            fd()
            getLoc()
        end
    elseif z < pos then
        face(east)
        while z < pos do
            fd()
            getLoc()
        end
    else
    end
end

function findY(height)
    if y > height then
        while y > height do
            dn()
            getLoc()
        end
    elseif y < height then
        while y < height do
            up()
            getLoc()
        end
    else
    end
end

function moveTo(newx, newy, newz)
    findY(newx)
    findX(newz)
    findZ(newy)
end

function goHome()
    getLoc()
    dumpTempLoc()
    findZ(tonumber(0))
    findX(tonumber(0))
    findY(tonumber(0))
    face(north)
    unload()
    getFuel()
end

function goBack()
    getTempLoc()
    moveTo(tarx, tary, tarz)
end

function findBedrock()
    while true do
		turtle.digDown()
		if not turtle.down() then
			break
		end
		y = y - 1
		report(y)
	end
	findY(y + 5)
	b = y
	report("Bedrock found!")
end

--USEFUL FUNCTIONS--

function clear(line, column)
    if line == nil then
        line = 1
    end
    if column == nil then
        column = 1
    end
    term.clear()
    term.setCursorPos(line, column)
end

function rest(count)
    while count > 0 do
        report("Sleeping... T.R: "..tostring(count).." sec.")
        sleep(1)
        count = count - 1
    end
end

function fill(slot)
    turtle.select(slot)
    while turtle.getItemCount(slot) < 64 do
       turtle.suck()
    end
    for i = 1, 16 do
        turtle.select(i)
        if i == slot then
        else
            if turtle.compareTo(slot) then
                turtle.drop()
            end
        end
    end
end

function emptyFrom(slot)
    for i = slot, 16 do
        turtle.select(i)
        turtle.drop()
    end
end

--JOB SPECIFIC FUNCTIONS--

function unload()
    face(east)
    emptyFrom(5)
    face(north)
end

function getFuel()
    face(west)
    fill(fuelSlot)
    face(north)
end

function gravel()
    turtle.select(gravelSlot)
    rest(1)
    if turtle.compare() then
        while turtle.compare() do
            report("Encountered Gravel")
            dig()
            rest(1)
        end
    end
end

function tossJunk()
    for slot = 1, 16 do
        turtle.select(slot)
        if turtle.getItemCount(slot) == 64 then
            if slot == cobbleSlot then
                turtle.drop(63)
                report("Dropping Junk.")
            elseif slot == dirtSlot then
                turtle.drop(63)
                report("Dropping Junk.")
            elseif slot == gravelSlot then
                turtle.drop(63)
                report("Dropping Junk.")
            else
            end
        end
    end
end

function checkFull()
    turtle.select(16)
    if turtle.getItemCount(16) > 1 then
        goHome()
        goBack()
    end
    turtle.select(fuelSlot)
    if turtle.getItemCount(fuelSlot) < 1 then
        goHome()
        goBack()
    end
end

function checkDig()
    tossJunk()
    checkFull()
    for slot = stoneSlot, cobbleSlot do
        turtle.select(slot)
        if turtle.compare(slot) then
            if slot == stoneSlot then
                turtle.select(cobbleSlot)
                dig()
                break
            elseif slot == dirtSlot then
                turtle.select(dirtSlot)
                dig()
                break
            elseif slot == gravelSlot then
                gravel()
                break
            elseif slot == cobbleSlot then
                report("Cobble generator found.")
                goHome()
            end
        else
        end
    end
    dig()
end

function evaluate()
    junk = 0
    for slot = stoneSlot, cobbleSlot do
        turtle.select(slot)
        if turtle.compare() then
            junk = junk + 1
        end
    end
    if junk == 0 then
        dig()
        report("Treasure!")
    else
    end
end

function findOre()
    report("Scanning...")
    lt()
    evaluate()
    lt()
    lt()
    evaluate()
    lt()
end

function digFd()
    checkDig()
    rest(1)
    checkDig()
    fd()
end

function branch()
    if h == west then
        nbl = bl - (2 * bl)
        while z > nbl do
            digFd()
            findOre()
        end
    elseif h == east then
        nbl = bl
        while z < nbl do
            digFd()
            findOre()
        end
    end
    findZ(t)
end

function trunk()
    findY(b)
    while x <= tl do
        for i = 1, 3 do
            digFd()
        end
        face(west)
        branch()
        face(east)
        branch()
        face(north)
    end
    b = b + 1
    dumpLoc()
    goHome()
end

--INTERFACE--

function startup()
    clear()
    print("Welcome to the BranchMine program! :)")
    print("please set a few starting variables.")
    sleep(1)
    clear()
    print("How long should the trunk be?")
    print()
    write("Trunk Length: ")
    input = read()
    tl = tonumber(input)
    print()
    print("trunk length set to "..tostring(tl))
    sleep(1)
    clear()
    print("How long should the branches be?")
    print()
    write("Branch Length: ")
    input = read()
    bl = tonumber(input)
    print()
    print("Branch length set to "..tostring(tl))
    sleep(1)
    clear()
    print("Thank you for your input.")
    print("Preparing files for mining operation.")
    dumpLoc()
    report("Getting fuel.")
    getFuel()
    report("Finding Bedrock layer.")
    findBedrock()
    dumpLoc()
end

--PROGRAM--

getLoc()
goHome()
while b < -5 do
    trunk()
end