WIP setup

--add this script to an Advanced Computer with the command:
-- pastebin get VbZ5tvq9 update
-- then use 'update' to get the stable version
-- or 'update wip' to get the WIP version

-- process command line parameters
local tArgs = { ... } -- get the command line arguments
local wip_path = nil
if #tArgs == 1 then
    wip_path = tArgs[1]
elseif #tArgs > 1 then
    print("Usage: update <wip_version_subfolder_on_the_url>")
    return
end

local repo_url = "https://www.20000blocks.com/twenty-k-scripts/"..((wip_path) and (wip_path.."/") or "stable/")

--- see if the file exists
function file_exists(_filename, _folder)
    local fullname = fs.combine( _folder or "", _filename )
    local f = fs.open(fullname, "rb")
    if f then f:close() end
    return f ~= nil
end

--- creates a new text file and writes a string to it
local function file_write(text, filename, path)
    if path then fs.makeDir(path) end
    local fullname = fs.combine(path or "",filename)
    local file = assert(fs.open(fullname, "w"), "error writing to file:"..fullname)
    file.write(text)
    file.close()
    return fullname
end

--- get all lines from a file, returns an empty
-- list/table if the file does not exist
function lines_from(file)
  if not file_exists(file) then return {} end
  lines = {}
  for line in io.lines(file) do
    lines[#lines + 1] = line
  end
  return lines
end

local function downloadScript(script_name, script_local_folder, extension_on_remote)
    -- the user agent needs to be renamed otherwise the default one is Java
    -- and Java is blocked by the .htaccess file on the www.20000blocks.com website
    local headers = {
        [ "User-Agent" ] = "20.000 BLOCKS"
    }
    local download_url = repo_url..script_name..(extension_on_remote or "")
    --print("Downloading from: "..download_url)
    local link = http.get( download_url, headers )
    if link then
        local script_body = link.readAll()
        return file_write(script_body, script_name, script_local_folder)
    else
        term.setTextColor(colors.red)
        print("Failed to download: "..script_name)
        return false
    end
    return false
end

local listfile = "filelist.txt"

local function downloadScripts()
    local scriptlistfile = downloadScript(listfile)
    if not scriptlistfile then
        print("requested version does not exist on the server")
        return false
    end
    local scriptlist = lines_from(scriptlistfile)
    for i, script in ipairs(scriptlist) do
        local i, j = string.find(script, "/")
        local scriptfolder = nil
        local scriptname = nil
        if i then
            scriptfolder = script:sub(1,i-1)
            scriptname = script:sub(i+1,-1)
        else
            scriptname = script
        end
        if not downloadScript(scriptname, scriptfolder, ".lua") then return false end
    end
    return true
end

-- do the installation
term.setTextColor(colors.green)
print("Updating to "..((wip_path) and ("VERSION: "..wip_path) or "STABLE VERSION"))
print("Installing 20.000 BLOCKS scripts...")
term.setTextColor(colors.white)

if not downloadScripts() then
    print("downloading scripts failed")
    os.exit()
end

term.setTextColor(colors.green)
print("20.000 BLOCKS scripts installed successfully!")
term.setTextColor(colors.white)
print("update complete!")
--[[
print("update complete! Rebooting...")
os.sleep(0.5)
shell.run("reboot")
--]]