stripmine

local function refuel()
    local fuelLevel = turtle.getFuelLevel()
    if fuelLevel == "unlimited" or fuelLevel > 0 then
        return
    end

    local function tryRefuel()
        for n=1,16 do
            if turtle.getItemCount(n) > 0 then
                turtle.select(n)
                if turtle.refuel(1) then
                    turtle.select(1)
                    return true
                end
            end
        end
        turtle.select(1)
        return false
    end

    if not tryRefuel() then
        print( "Add more fuel to continue." )
        while not tryRefuel() do
            sleep(1)
        end
        print( "Resuming branch mine..." )
    end
end

local function tryDig()
    while turtle.detect() do
        if turtle.dig() then
            sleep(0.5)
        else
            return false
        end
    end
    return true
end

local function tryDigUp()
    while turtle.detectUp() do
        if turtle.digUp() then
            sleep(0.5)
        else
            return false
        end
    end
    return true
end

local function tryDigDown()
    while turtle.detectDown() do
        if turtle.digDown() then
            sleep(0.5)
        else
            return false
        end
    end
    return true
end

local function tryUp()
    refuel()
    while not turtle.up() do
        if turtle.detectUp() then
            if not tryDigUp() then
                return false
            end
        elseif turtle.attackUp() then
        else
            sleep( 0.5 )
        end
    end
    return true
end

local function tryDown()
    refuel()
    while not turtle.down() do
        if turtle.detectDown() then
            if not tryDigDown() then
                return false
            end
        elseif turtle.attackDown() then
        else
            sleep( 0.5 )
        end
    end
    return true
end

local function tryForward()
    refuel()
    while not turtle.forward() do
        if turtle.detect() then
            if not tryDig() then
                return false
            end
        elseif turtle.attack() then
        else
            sleep( 0.5 )
        end
    end
    return true
end

local function tryBuildPath(left,right)
    refuel()
    turtle.select(2)
    while not turtle.detectDown() do
        if turtle.placeDown() then
        elseif turtle.attackDown() then
        else
            sleep( 0.5 )
        end
    end
    if left then
        turtle.turnLeft()
        while not turtle.detect() do
            if turtle.place() then
            elseif turtle.attack() then
            else
                sleep( 0.5 )
            end
        end
        turtle.turnRight()
    end
    if right then
        turtle.turnRight()
        while not turtle.detect() do
            if turtle.place() then
            elseif turtle.attack() then
            else
                sleep( 0.5 )
            end
        end
        turtle.turnLeft()
    end
    return true
end


local function excavate_height(settings, h, l, return_to_origin, connect_branch_ends, branch_side, wall_left, wall_right)
    -- clear h*l area
    -- tryBuildPath(wall_left, wall_right)
    -- tryDigUp()
    for n=1,l do
        tryForward()
        tryBuildPath(wall_left, wall_right)
        tryDigUp()
    end
    if h == 3 then
        turtle.turnLeft()
        turtle.turnLeft()
        tryUp()
        tryDigUp()
        tryUp()
        for n=1,l do
            tryForward()
        end
        tryDown()
        tryDown()
        turtle.turnRight()
        turtle.turnRight()
    elseif h == 4 then
        turtle.turnLeft()
        turtle.turnLeft()
        tryUp()
        tryDigUp()
        tryUp()
        tryDigUp()
        for n=1,l do
            tryForward()
            tryDigUp()
        end
        tryDown()
        tryDown()
        turtle.turnRight()
        turtle.turnRight()
    else
        if connect_branch_ends then
            if branch_side == "right" then
                turtle.turnRight()
                tryDig()
                turtle.turnLeft()
                turtle.turnLeft()
                tryBuildPath(false, true)
                for i=1,settings["branch_spacing"] do
                    tryForward()
                    tryBuildPath(true, true)
                    tryDigUp()
                end
                turtle.turnRight()
                turtle.turnRight()
                for i=1,settings["branch_spacing"] do
                    tryForward()
                end
                turtle.turnLeft()
            elseif branch_side == "left" then
                turtle.turnLeft()
                tryDig()
                turtle.turnRight()
                turtle.turnRight()
                tryBuildPath(true, false)
                for i=1,settings["branch_spacing"] do
                    tryForward()
                    tryBuildPath(true, true)
                    tryDigUp()
                end
                turtle.turnRight()
                turtle.turnRight()
                for i=1,settings["branch_spacing"] do
                    tryForward()
                end
                turtle.turnRight()
            end
        end
        if return_to_origin then
            turtle.turnRight()
            turtle.turnRight()
            for n=1,l do
                tryForward()
            end
            turtle.turnLeft()
            turtle.turnLeft()
        end
    end
end


local function excavate(settings, w, h, l, return_to_origin, connect_branch_ends, branch_side)
    if w == 1 then
        excavate_height(settings, h, l, return_to_origin, connect_branch_ends, branch_side, true, true)
    elseif w == 3 then
        excavate_height(settings, h, l, true, connect_branch_ends, branch_side, false, false)
        turtle.turnLeft()
        tryForward()
        turtle.turnRight()
        excavate_height(settings, h, l, true, connect_branch_ends, branch_side, true, false)
        turtle.turnRight()
        tryForward()
        tryForward()
        turtle.turnLeft()
        excavate_height(settings, h, l, true, connect_branch_ends, branch_side, false, true)
        turtle.turnLeft()
        tryForward()
        turtle.turnRight()
        if not return_to_origin then
            for n=1,l do
                tryForward()
            end
        end
    elseif w == 5 then
        excavate_height(settings, h, l, true, connect_branch_ends, branch_side, false, false)
        turtle.turnLeft()
        tryForward()
        turtle.turnRight()
        excavate_height(settings, h, l, true, connect_branch_ends, branch_side, false, false)
        turtle.turnLeft()
        tryForward()
        turtle.turnRight()
        excavate_height(settings, h, l, true, connect_branch_ends, branch_side, true, false)
        turtle.turnRight()
        tryForward()
        tryForward()
        tryForward()
        turtle.turnLeft()
        excavate_height(settings, h, l, true, connect_branch_ends, branch_side, false, false)
        turtle.turnRight()
        tryForward()
        turtle.turnLeft()
        excavate_height(settings, h, l, true, connect_branch_ends, branch_side, false, true)
        turtle.turnLeft()
        tryForward()
        tryForward()
        turtle.turnRight()
        if not return_to_origin then
            for n=1,l do
                tryForward()
            end
        end
    end
end


local function dig_branches(settings)
    print("Beginning to excavate branches")

    local num_segments = math.floor(settings["trunk_length"] / (settings["branch_spacing"]+1))
    local return_to_origin = true

    for i=1,num_segments do
        print("Currently working on branch pairs " .. i .. "/" .. num_segments)
        tryForward()
        print("Beginning to excavate right branch")
        turtle.turnRight()
        -- skip gap between trunk center and side wall
        if settings["trunk_size"] == "medium" then
            tryForward();
        elseif settings["trunk_size"] == "large" then
            tryForward();
            tryForward();
        end
        excavate(
            settings,
            1,
            2,
            settings["branch_length"],
            return_to_origin,
            settings["connect_branch_ends"],
            "right"
        )
        turtle.turnLeft()
        print("Beginning to excavate left branch")
        turtle.turnLeft()
        -- Skip gap between trunk center and side wall
        -- Include extras to compensate for gap skipping
        -- from the other branch side
        if settings["trunk_size"] == "medium" then
            tryForward();
            tryForward();
        elseif settings["trunk_size"] == "large" then
            tryForward();
            tryForward();
            tryForward();
            tryForward();
        end
        excavate(
            settings,
            1,
            2,
            settings["branch_length"],
            return_to_origin,
            settings["connect_branch_ends"],
            "left"
        )
        turtle.turnRight()
        turtle.turnRight()
        -- Include extras to compensate for gap skipping
        -- from the other branch side
        if settings["trunk_size"] == "medium" then
            tryForward();
        elseif settings["trunk_size"] == "large" then
            tryForward();
            tryForward();
        end
        turtle.turnLeft()
    -- move forward a segment
        for s=1,settings["branch_spacing"] do
            tryForward()
        end
    end
    print("Done excavating branches")
end


local function dig_trunk_segment(settings)
    print("Beginning trunk segment")
    local trunk_width
    local trunk_height
    if settings["trunk_size"] == "small" then
        trunk_width = 1
        trunk_height = 2
    elseif settings["trunk_size"] == "medium" then
        trunk_width = 3
        trunk_height = 3
    elseif settings["trunk_size"] == "large" then
        trunk_width = 5
        trunk_height = 4
    end
    local return_to_origin, connect_branch_ends, branch_side = false, false, false
    excavate(
        settings,
        trunk_width,
        trunk_height,
        settings["branch_spacing"]+1,
        return_to_origin,
        connect_branch_ends,
        branch_side
    )
    print("End of trunk segment")
end


local function dig_trunk(settings)
    print("Beginning to excavate main trunk")

    local num_segments = math.floor(settings["trunk_length"] / (settings["branch_spacing"]+1))

-- Dig trunk segments
    for i=1,num_segments do
        print("Currently working on segment " .. i .. "/" .. num_segments)
        dig_trunk_segment(settings)
    end
    print("Done excavating main trunk.")
    -- return to origin
    turtle.turnLeft()
    turtle.turnLeft()
    for a = 1,num_segments*(settings["branch_spacing"]+1) do
        tryForward()
    end
    turtle.turnLeft()
    turtle.turnLeft()
end


local function start_digging(settings)
    if settings["dig_main_trunk"] then
        dig_trunk(settings)
    end
    dig_branches(settings)
end

--[[ INTERFACE
================================================================== ]]

local
    about_program,
    view_help,
    config_trunk_length,
    config_trunk_size,
    config_trunk,
    config_branch_spacing,
    config_branch_length,
    config_branches,
    view_settings,
    main_menu

about_program = function(settings)
    shell.run('clear')
    print("      BRANCH MINE | ABOUT PROGRAM      ")
    print("           v1.0 (2012-12-29)           ")
    print("                                       ")
    print(" Coded by Sandwich (@sandwich_hlp on   ")
    print(" Twitter; sandwichHLP on YouTube)      ")
    print(" Some functions taken from the 'tunnel'")
    print(" program included with ComputerCraft / ")
    print(" Feed The Beast.                       ")
    print("                                       ")
    print("                                       ")
    print("         Press ENTER to continue       ")
    io.read()
    main_menu(settings)
end

view_help = function(settings)
    shell.run('clear')
    print("       BRANCH MINE | HELP & TIPS       ")
    print("                                       ")
    print("Place COAL into Slot 1 (charcoal won't ")
    print("get auto-restocked during mining).     ")
    print("Place COBBLESTONE into Slot 2 (used for")
    print("placing down blocks)                   ")
    print("                                       ")
    print("Fill remaining slots with single blocks")
    print("that you want the Turtle to keep, such ")
    print("as iron, gold, and diamonds.           ")
    print("                                       ")
    print("         Press ENTER to continue       ")
    io.read()
    main_menu(settings)
end


config_trunk_length = function(settings)
    shell.run('clear')
    print(" BRANCH MINE | MAIN TRUNK CONFIGURATION")
    print("                                       ")
    if settings["dig_main_trunk"] == false then
        print("Even though the Main Trunk is currently")
        print("set to NOT be dug out, this value still")
        print("is used to calculate how many branches ")
        print("should be dug.                         ")
        print("                                       ")
    end
    print(" Enter new length and press ENTER:     ")
    local input = io.read()
    input = input + 0 -- typecast to number
    if type(input) == "number" then
        settings["trunk_length"] = input
        config_trunk(settings)
    else
        print("Invalid input - numbers only please")
        textutils.slowPrint(".......................................")
        config_trunk_length(settings)
    end
end


config_trunk_size = function(settings)
    shell.run('clear')
    print(" BRANCH MINE | MAIN TRUNK CONFIGURATION")
    print("                                       ")
    print(" 1. Small - 2 high x 1 wide            ")
    print(" 2. Medium - 3 high x 3 wide           ")
    print(" 3. Large - 4 high x 5 wide            ")
    print("                                       ")
    print(" Select size [1-3] and press ENTER:  ")
    local input = io.read()
    if (input=="1") then
        settings["trunk_size"] = "small"
        config_trunk(settings)
    elseif (input=="2") then
        settings["trunk_size"] = "medium"
        config_trunk(settings)
    elseif (input=="3") then
        settings["trunk_size"] = "large"
        config_trunk(settings)
    else
        print("Invalid input - enter a number 1-3.")
        textutils.slowPrint(".......................................")
        config_trunk_size(settings)
    end
end


config_trunk = function(settings)

    shell.run('clear')

    print(" BRANCH MINE | MAIN TRUNK CONFIGURATION")
    print("                                       ")
    print(" (Current values are in parentheses)   ")
    print("                                       ")
    write("1. Toggle Main Trunk Excavation ")
    if settings["dig_main_trunk"] then write("(Dig)\n") else write("(Skip)\n") end
    print("2. Edit Length (" .. settings["trunk_length"] .. ")")
    write("3. Edit Size ")
    if settings["trunk_size"] == "small" then
        write("(Small - 2h x 1w)\n")
    elseif settings["trunk_size"] == "medium" then
        write("(Medium - 3h x 3w)\n")
    elseif settings["trunk_size"] == "large" then
        write("(Large - 4h x 5w)\n")
    end
    if settings["dig_main_trunk"] == false then
        print(" (affects start points for branches)")
    end
    print("4. Main Menu                           ")
    print("                                       ")
    print(" Type a number [1-4] and press ENTER:  ")
    local input = io.read()
    if input == "1" then
        settings["dig_main_trunk"] = not settings["dig_main_trunk"]
        config_trunk(settings)
    elseif input == "2" then
        config_trunk_length(settings)
    elseif input == "3" then
        config_trunk_size(settings)
    elseif input == "4" then
        main_menu(settings)
    else
        print("Invalid input - enter a number 1-4")
        textutils.slowPrint(".......................................")
        config_trunk(settings)
    end
end


config_branch_spacing = function(settings)
    shell.run('clear')
    print("  BRANCH MINE | BRANCH CONFIGURATION   ")
    print("                                       ")
    print("This is how many blocks will be between")
    print("each branch. 3 is recommended.         ")
    print("                                       ")
    print("    Enter distance between branches    ")
    print("           and press ENTER:            ")
    local input = io.read()
    input = input + 0 -- typecast to number
    if type(input) == "number" then
        settings["branch_spacing"] = input
        config_branches(settings)
    else
        print("Invalid input - numbers only please")
        textutils.slowPrint(".......................................")
        config_branch_spacing(settings)
    end
end


config_branch_length = function(settings)
    shell.run('clear')
    print("  BRANCH MINE | BRANCH CONFIGURATION   ")
    print("                                       ")
    print(" How long should each branch be? Please")
    print(" note that this is counted from the    ")
    print(" walls of the main trunk, not from the ")
    print(" center.                               ")
    print("                                       ")
    print("     Enter length and press ENTER:     ")
    local input = io.read()
    input = input + 0 -- typecast to number
    if type(input) == "number" then
        settings["branch_length"] = input
        config_branches(settings)
    else
        print("Invalid input - numbers only please")
        textutils.slowPrint(".......................................")
        config_branch_length(settings)
    end
end


config_branches = function(settings)

    shell.run('clear')

    print("  BRANCH MINE | BRANCH CONFIGURATION   ")
    print("                                       ")
    print(" (Current values are in parentheses)   ")
    print("                                       ")
    print("1. Edit Spacing (" .. settings["branch_spacing"] .. ")")
    print("2. Edit Length: (" .. settings["branch_length"] .. ")")
    write("3. Toggle Connect Branch Ends ")
    if settings["connect_branch_ends"] then write("(Yes)\n") else write("(No)\n") end
    print("4. Main Menu                           ")
    print("                                       ")
    print(" Type a number [1-4] and press ENTER:  ")
    local input = io.read()
    if input == "1" then
        config_branch_spacing(settings)
    elseif input == "2" then
        config_branch_length(settings)
    elseif input == "3" then
        settings["connect_branch_ends"] = not settings["connect_branch_ends"]
        config_branches(settings)
    elseif input == "4" then
        main_menu(settings)
    else
        print("Invalid input - enter a number 1-3")
        textutils.slowPrint(".......................................")
        config_branches(settings)
    end
end


view_settings = function(settings)

    shell.run('clear')

    print("      BRANCH MINE | VIEW SETTINGS      ")
    print("                                       ")
    print("Main Trunk Length: " .. settings["trunk_length"])
    write("Main Trunk Size: ")
    if settings["trunk_size"] == "small" then
        write("Small - 2h x 1w\n")
    elseif settings["trunk_size"] == "medium" then
        write("Medium - 3h x 3w\n")
    elseif settings["trunk_size"] == "large" then
        write("Large - 4h x 5w\n")
    end
    write("Excavate Main Trunk: ")
    if settings["dig_main_trunk"] then write("Yes\n") else write ("No\n") end
    print("Spacing Between Branches: " .. settings["branch_spacing"])
    print("Branch Length: " .. settings["branch_length"])
    write("Connect Branch Ends: ")
    if settings["connect_branch_ends"] then write("Yes\n") else write ("No\n") end
    print("                                       ")
    print("         Press ENTER to continue       ")
    io.read()
    main_menu(settings)
end

main_menu = function(settings)

    shell.run('clear')

    print("        BRANCH MINE | MAIN MENU        ")
    print("                                       ")
    print(" 1. View settings                      ")
    print(" 2. Configure main trunk               ")
    print(" 3. Configure branches                 ")
    print(" 4. Help                               ")
    print(" 5. About this program                 ")
    print(" 6. BEGIN                              ")
    print("                                       ")
    print(" Type a number 1-6 and press ENTER     ")

    local input = io.read()
    if input == "1" then
        view_settings(settings)
    elseif input == "2" then
        config_trunk(settings)
    elseif input == "3" then
        config_branches(settings)
    elseif input == "4" then
        view_help(settings)
    elseif input == "5" then
        about_program(settings)
    elseif input == "6" then
        start_digging(settings)
    else
        print("Invalid input - enter a number 1-6")
        textutils.slowPrint(".......................................")
        main_menu(settings)
    end
end


-- DEFAULTS
local settings={}
settings["trunk_length"] = 20
settings["trunk_size"] = "medium"
settings["dig_main_trunk"] = true
settings["branch_spacing"] = 3
settings["branch_length"] = 50
settings["connect_branch_ends"] = true

main_menu(settings)