--[[
	By: rater193
	Enjoy the script!
]]
--CONFIGURATION
local CONFIG = {}
CONFIG.GIT = {}
CONFIG.GIT.NAME = "rater193"
CONFIG.GIT.REPO = "OpenComputers-1.7.10-Base-Monitor"





local shell = require("shell")
local internet = require("internet")
local data = require("component").data
local fs = require("filesystem")

--downloading the json libs if they do not exsist
shell.execute('mkdir /lib')
shell.execute('wget -fq "https://raw.githubusercontent.com/rater193/OpenComputers-1.7.10-Base-Monitor/master/lib/json.lua" "/lib/json.lua"')
local json = require("json")

--these are some functions for handling downloading data from http requests
local function getStringFromResponce(responce)
	local ret = ""
	local resp = responce()
	while(resp~=nil) do
		ret = ret..tostring(resp)
		resp = responce()
	end
	return ret
end

local function getHTTPData(url)
	local ret = nil
	local request, responce = pcall(internet.request, url)
	if(request) then
		ret = getStringFromResponce(responce)
	end
	return ret
end

--this is a function for downloading a repository tree
local function downloadTree(treedataurl, parentdir)
	--this is used to make it so you dont have to set the parent dir it will default to the root directory
	if(not parentdir) then parentdir = "" end


	local treedata = json.decode(getHTTPData(treedataurl))

	for _, child in pairs(treedata.tree) do
		--os.sleep(0.1)
		local filename = parentdir.."/"..tostring(child.path)
		if(child.type=="tree") then
			--print("Downloading tree")
			print("Checking directory, "..tostring(filename))
			downloadTree(child.url, filename)
		else
			shell.execute('rm -f "'..tostring(filename)..'"')
			--print("Installing file")
			--local repodata = data.decode64(json.decode(getHTTPData(child.url)).content)
			print("downloading "..filename)
			local repodata = getHTTPData("https://raw.githubusercontent.com/"..tostring(CONFIG.GIT.NAME).."/"..tostring(CONFIG.GIT.REPO).."/master/"..tostring(filename))
			local file = fs.open(filename, "w")
			file:write(repodata)
			file:close()
		end
	end
end


--this is used for getting the current version of the OS
local file = fs.open("curversion", "r")
_G.OSVersion = file:read(10000)
file:close()


--the data for the json api for the repository
local data = getHTTPData("https://api.github.com/repos/"..tostring(CONFIG.GIT.NAME).."/"..tostring(CONFIG.GIT.REPO).."/git/refs")


if(data) then
	print("Loading updates")
	--print("data: "..tostring(data))
	git = json.decode(data)[1].object
	
	--[[
		sha
		type
		url
	]]

	--This is the version ID we are going to compare, to see if we are outdated!
	local newversion = git.sha
	print("newversion: ",newversion)
	print("_G.OSVersion: ",_G.OSVersion)

	if(newversion ~= _G.OSVersion) then

		--this is the repositories commit api url
		local file = fs.open("curversion", "w")
		file:write(newversion)
		file:close()

		local gitcommit = git.url

		local commitdata = getHTTPData(gitcommit)

		if(commitdata) then
			print("Loading commit data")
			--print("commitdata: ", tostring(commitdata))
			--print("length: ", tostring(string.len(commitdata)))

			local commitdatatree = json.decode(commitdata).tree
			--print("commitdatatree: ", tostring(commitdatatree))

			downloadTree(commitdatatree.url)
		end


		--[[for _, v in pairs(git) do
			print(tostring(_), " = ", tostring(v))
		end]]
	else
		print("OS is already up to date!")
	end
end

print("Update complete! enjoy!")