--(( Settings ))--

-- wether or not if the turtle should
-- attack mobs if they are in their way
local killMobs = true

-- 
local destroyBlocks = false

-- apis to load, file path
-- will be loaded in ascending order, top to bottom
-- will ignore file extension when loading
-- ex: 'dig.lua' can be refered as 'dig'
local apis = {
	"dig.lua",
	"gps.lua",
	"farm.lua",
	"item.lua",
}

_G.oldAPISyntax = "_old"

--(( Variables ))--

-- the directory of the program running
local programDir = shell.getRunningProgram() -- get the full path
programDir = programDir:match("^.+/") or "" -- get the folder

-- load apis


--(( Functions ))--

-- table input should be indexed by integers
-- example input: {"john","brad","tony","steve"}   ", "   ", and "
-- example output: "john, brad, tony, and steve"
local function combine( t,seperator,lastSeperator )
	local str = ""

	for index,value in ipairs(t) do
		if index == 1 then
			str = str .. value
		elseif index > 1 and index < #t then
			str = str .. seperator .. value
		elseif index == #t then
			str = str .. lastSeperator .. value
		end
	end

	return str
end

local function loadAPIs( t )
	local failed = {} -- apis that failed to load
	-- loop through all apis
	for _,path in ipairs(apis) do
		local fullPath = programDir .. path
		local fileName = fs.getName(fullPath)-- remove directory

		local apiName = fileName
		apiName = apiName:match("^.+%.") or apiName.."." -- remove the file extension
		apiName = apiName:sub(0,-2) -- remove the dot at the end

		-- if its already loaded; unload it first
		--if _G[apiName] then
		--	os.unloadAPI(apiName)
		--end

		-- load api, move its global position
		local oldvar = _G[fileName]
		if os.loadAPI(fullPath) then
			-- in case theres an api already loaded
			if _G[apiName] ~= nil and _G[apiName.._G.oldAPISyntax]==nil then
				_G[apiName.._G.oldAPISyntax] = _G[apiName]
			end

			_G[apiName] = _G[fileName]
		else
			table.insert(failed,fullPath)
		end
		-- in case of overriding, reset
		_G[fileName] = oldvar

		-- give it functions
		if type(_G[apiName]) == "table" then
			if type(_G[apiName].init) == "function" then
				local state,err = pcall(_G[apiName].init,_G)
				if not state then print(apiName..": "..err)table.insert(failed,fullPath) end
			end
		end
	end

	if #failed == 1 then
		error("Unable to load API "..failed[1].."!",0)
	elseif #failed > 1 then
		error("Unable to load APIs "..combine(failed,", ",", and ").."!",0)
	end
end

function _G.mult( num )
	if num > 0 then return 1 end
	if num < 0 then return -1 end
	return 0
end

--(( Error checking ))--

-- load apis
loadAPIs()

--(( Main program ))--
print("main step 1")
farm.setOffset( 3,4,1 )print("main step 2")
farm.setSize( 7,-5,4 )print("main step 3")
if not gps.autoSetPosition() then error("unable to locate position via gps",0) end print("main step 4")
gps.setHome(245,60,-765,gps.east)print("main step 5")
gps.goto(gps.getHome())

item.addStoragePathCheckpoint(246,60,-765)
item.addStoragePathCheckpoint(244,60,-765)
item.setItemAccess(item.types.dirt,244,60,-766,gps.down)
item.setItemAccess(item.types.sapling,244,60,-765,gps.down)
item.setItemAccess(item.types.dropoff,244,60,-764,gps.down)


--(( EOF ))--