module (..., package.seeall)

require("fs")
require("posix")
-- require("procps")
-- require("daemoncontrol")
-- require("processinfo")

-- Set variables
local config_file = "/etc/ssh/sshd_config"
local packagename = "openssh"
local processname = "sshd"

-- valid keywords and default config
local default = {
	Port = 22,
	ListenAddress = "0.0.0.0",
	PermitRootLogin = true,
	PasswordAuthentication = true,
	UseDNS = true
}


-- This function is used to get config_content.
local function process_status_text(procname)
	local t = procps.pidof(procname)
	if (t) and (#t > 0) then
		return "Enabled"
	else
		return "Disabled"
	end
end

-- return "Yes" or "No" on true/false or value as string
local function config_value(value)
	if type(value) == "boolean" then
		if value then
			return "Yes"
		else
			return "No"
		end
	end
	return tostring(value)
end

function read_config()
	local conf = {}
	local f = io.open(config_file, "r")
	local line, key, _, k, v
	
	if not f then
		return nil
	end

	-- clone default conf
	for k, v in pairs(default) do
		conf[k] = v
	end

	for line in f:lines() do
		line = string.gsub(line, "#.*", "")
		for key, _ in pairs(default) do
			local k,v = string.match(line, "^("..key..")%s+(.*)")
			if k then
				conf[k] = v
			end
		end
	end
	f:close()
	return conf
end

function write_config(config)
	local k, v, lines, i,j 
	local conf = {}

	-- filter out unsupported keys
	for k,v in pairs(config) do
		if default[k] ~= nil then
			conf[k] = v
		end
	end

	lines = fs.read_file_as_array(config_file)
	for i, j in ipairs(lines) do
		for k, v in pairs(conf) do
			if string.match(j, "^#?"..k.."%s+") then
				lines[i] = k .. " " .. config_value(v)
				conf[k] = nil
			end
		end
	end

	-- append config opts to end
	for k,v in pairs(conf) do
		table.insert(lines, k .. " " .. config_value(v))
	end

	-- write file
	posix.mkdir(posix.dirname(config_file))
	local f = io.open(config_file, "w")
	for _,i in ipairs(lines) do
		f:write(i.."\n")
	end
	f:close()
end