OpenComputer - Lettuce farm

local robot = require("robot")
local side = require("sides")
local component = require("component")
local shell = require("shell")
local computer = require("computer")

local field_size_x = 34
local field_size_z = 9

-- Robot movement encapsulations

function forward(amount)
    local i

    i = amount
    if not amount then
        i = 1
    end
    while i > 0 do
        if robot.forward() then
            i = i - 1
        else
            os.sleep(2)
            print("Can't forward. Please move this shit.")
        end
    end
end

function up(amount)
    if not amount then
        amount = 1
    end
    while amount > 0 do
        if robot.up() then
            amount = amount - 1
        else
            os.sleep(2)
            print("Can't go up. Please move this shit.")
        end
    end
end

function down(amount)
    if not amount then
        amount = 1
    end
    while amount > 0 do
        if robot.down() then
            amount = amount - 1
        else
            os.sleep(2)
            print("Can't go down. Please move this shit.")
        end
    end
end

function move_orientation(orientation)
    if orientation == side.left then
        robot.turnLeft()
    elseif orientation == side.right then
        robot.turnRight()
    elseif orientation == side.back then
        robot.turnRight()
        robot.turnRight()
    end
end

function move_orientation_revert(orientation)
    if orientation == robot.left then
        robot.turnRight()
    elseif orientation == robot.right then
        robot.turnLeft()
    elseif orientation == robot.back then
        robot.turnLeft()
        robot.turnLeft()
    end
end

function move(amount, orientation)
    if orientation then
        move_orientation(orientation)
        if orientation == up then
            up(amount)
        elseif orientation == down then
            down(amount)
        else
            forward(amount)
        end
        move_orientation_revert(orientation)
    else
        forward(amount)
    end
end


-- Inventory gestion functions

function push_item_after_slot(from)
    local slot = from + 1

    robot.select(from)
    while slot < robot.inventorySize() and component.inventory_controller.getStackInInternalSlot(slot) do
        slot = slot + 1
    end
    if slot < robot.inventorySize() and robot.transferTo(slot) then
        return true
    end
    return false
end

function select_item(item, meta)
    local slot = 1
    local size = robot.inventorySize()

    while slot <= size do
        local data = component.inventory_controller.getStackInInternalSlot(slot)
        if data and data.name == item and (not meta or data.damage == meta) then
            robot.select(slot)
            return true
        end
        slot = slot + 1
    end
    return false
end

function select_next_item(slot, item, meta)
    local data
    local size = robot.inventorySize()

    while slot <= robot.inventorySize() do
        data = component.inventory_controller.getStackInInternalSlot(slot)
        if data and data.name == item and (not meta or meta == data.damage) then
            robot.select(slot)
            return true
        end
        slot = slot + 1
    end
    return false
end

function repack_item(item, meta)
    local slot = 1
    local data

    if item == "minecraft:stone_pickaxe" or item == "minecraft:diamond_pickaxe" then
        return true
    end
    while slot < robot.inventorySize() do
        data = component.inventory_controller.getStackInInternalSlot(slot)
        if not data or ((data.name == item and data.size < 64) and (not meta or meta == data.damage)) then
            if select_next_item(slot + 1, item, meta) then
                robot.transferTo(slot)
                data = component.inventory_controller.getStackInInternalSlot(slot)
            else
                return true
            end
        else
            slot = slot + 1
        end
    end
    return true
end

function empty_slot_amount()
    local slot = 1
    local empty_slots = 0
    local size = robot.inventorySize()

    while slot <= size do
        if not component.inventory_controller.getStackInInternalSlot(slot) then
            empty_slots = empty_slots + 1
        end
        slot = slot + 1
    end
    return empty_slots
end

function select_item_out_of_workbench(item, meta)
    local slot = 4
    local data
    local size = robot.inventorySize()

    while slot <= size do
        if slot == 5 or slot == 9 then
            slot = slot + 3
        end
        data = component.inventory_controller.getStackInInternalSlot(slot)
        if data and data.name == item and (not meta or data.damage == meta) then
            robot.select(slot)
            return true
        end
        slot = slot + 1
    end
    return false
end

function select_empty_slot()
    local slot = robot.inventorySize()

    while slot > 0 do
        if not component.inventory_controller.getStackInInternalSlot(slot) then
            robot.select(slot)
            return true
        end
        slot = slot - 1
    end
    return false
end

-- Crafting functions

function place_item_for_craft(item, to, meta, amount)
    local craft = {}

    if not amount then
        amount = 1
    end
    craft[1] = 1
    craft[2] = 2
    craft[3] = 3
    craft[4] = 5
    craft[5] = 6
    craft[6] = 7
    craft[7] = 9
    craft[8] = 10
    craft[9] = 11
    if to > 9 then
        print("place_item_for_craft: slot can't be > than 9")
        os.exit()
    end
    if select_item_out_of_workbench(item, meta) and robot.transferTo(craft[to], amount) then
        return true
    end
    return false
end

function free_crafting_table()
    local slot = 1
    local data
    local tried = false

    while slot <= 11 do
        if slot ~= 4 and slot ~= 8 then
            if component.inventory_controller.getStackInInternalSlot(slot) and not push_item_after_slot(slot) and not tried then
                clean_inventory()
                tried = true
            elseif component.inventory_controller.getStackInInternalSlot(slot) and not push_item_after_slot(slot) then
                return false
            end
        end
        slot = slot + 1
    end
    return true
end


-- External storage gestion functions

function get_free_slot_in_chest(chest_side)
    local slot
    local inv_size
    local data
    local reason

    slot = 1
    inv_size, reason = component.inventory_controller.getInventorySize(chest_side)
    if not inv_size then
        print("Failed to get free slot in chest: " .. reason)
        return false
    end
    while slot < inv_size do
        data = component.inventory_controller.getStackInSlot(chest_side, slot)
        if not data then
            return slot
        end
        slot = slot + 1
    end
    return false
end

function dump_slot_to_chest(chest_side, from_slot, amount, to_slot)
    if not to_slot then
        to_slot = get_free_slot_in_chest(chest_side)
        if not to_slot then
            return false
        end
    end
    robot.select(from_slot)
    if not amount then
        component.inventory_controller.dropIntoSlot(side.front, to_slot)
    else
        component.inventory_controller.dropIntoSlot(side.front, to_slot, amount)
    end
    return true
end

function drop_item_to_chest(chest_side, item, meta)
    while select_item(item, meta) do
        if not dump_slot_to_chest(chest_side, robot.select()) then
            return false
        end
    end
    return true
end

function get_item_from_chest(chest_side, name, meta, amount)
    local slot
    local data = {}
    local chest_size

    chest_size = component.inventory_controller.getInventorySize(chest_side)
    slot = 1
    if not chest_size or chest_size <= 0 then
        return false
    end
    while slot <= chest_size do
        data = component.inventory_controller.getStackInSlot(side.front, slot)
        if data and data.name == name and (not meta or data.damage == meta) then
            if amount then
                component.inventory_controller.suckFromSlot(chest_side, slot, amount)
            else
                component.inventory_controller.suckFromSlot(chest_side, slot)
            end
            return true
        end
        slot = slot + 1
    end
    return false
end


-- World interations functions

function get_bloc(orientation)
    local bloc = {}

    bloc["bloc"] = component.geolyzer.analyze(orientation)
    bloc["side"] = orientation
    return bloc
end

function get_blocs_around()
    local bloc = {}

    bloc[1] = get_bloc(side.front)
    bloc[2] = get_bloc(side.back)
    bloc[3] = get_bloc(side.up)
    bloc[4] = get_bloc(side.down)
    bloc[5] = get_bloc(side.left)
    bloc[6] = get_bloc(side.right)
    return bloc
end

function can_drop_in_chest()
    local i

    i = 1
    bloc = get_blocs_around()
    while i <= #bloc do
        if bloc[i]["bloc"].name == "ironchest:BlockIronChest" or bloc[i]["bloc"].name == "minecraft:chest" then
            return bloc[i]["side"]
        end
        i = i + 1
    end
    return false
end

function craft_and_store_food()
    local chest_side

    chest_side = can_drop_in_chest()
    if not chest_side then
        print("No chest found")
        return false
    end
    drop_item_to_chest(chest_side, "harvestcraft:lettuceItem")
    if not free_crafting_table() or not place_item_for_craft("harvestcraft:potItem", 1, 0) then
        return false
    end
    get_item_from_chest(chest_side, "harvestcraft:lettuceItem", nil, 21)
    while place_item_for_craft("harvestcraft:lettuceItem", 2, 0, 21) do
        component.crafting.craft()
        select_empty_slot()
        drop_item_to_chest(chest_side, "harvestcraft:stockItem")
        get_item_from_chest(chest_side, "harvestcraft:lettuceItem", nil, 21)
    end
    return true
end


-- Core functions

function line(amount)
    robot.placeDown()
    while amount > 0 do
        forward()
        robot.placeDown()
        amount = amount - 1
    end
end

function core(max_x, max_z)
    local i

    i = 0
    if not select_item("harvestcraft:potItem") then
        return false
    end
    while i < max_z do
        line(max_x)
        if i < max_z - 1 then
            if i % 2 == 0 then
                robot.turnLeft()
            else
                robot.turnRight()
            end
            forward()
            if i % 2 == 0 then
                robot.turnLeft()
            else
                robot.turnRight()
            end
        end
        i = i + 1
    end
    move_orientation(side.back)
    forward(max_x)
    move_orientation(side.left)
    forward(max_z - 1)
    move_orientation(side.left)
    move_orientation(side.back)
    craft_and_store_food()
    move_orientation(side.back)
end
while true do
    core(field_size_x, field_size_z)
    os.sleep(200)
end