module(..., package.seeall)

-- Load libraries
require("modelfunctions")
require("validator")

-- Set variables
local configfile = "/etc/opennhrp/opennhrp.conf"
local processname = "opennhrp"
local packagename = "opennhrp"

local descr = {
	Type = {
	['incomplete']="The protocol address is being resolved",
	['negative']="This protocol address is not available",
	['cached']="Protocol address was resolved successfully",
	['route']="This is a dynamic shortcut",
	['dynamic']="This entry is from a node that connected to us",
	['local']="Local interface address",
	['static']="Static mapping from configuration file (e.g. address of core)",
	},
	Flags= {
--	['up']="Connection is fully usable",
	['lower-up']="ipsec connections is up, but registration is not yet done",
	},
}

-- ################################################################################
-- LOCAL FUNCTIONS

local function opennhrpctl_show()
	local peers_list = cfe({ type="structure", value={}, label="Peers" })
	local opennhrpstatus = cfe({ value="Show report not available", label="Status" })
	local cmd = "/usr/sbin/opennhrpctl show 2>/dev/null"
	local f = io.popen( cmd )
	local content = f:read("*a")
	f:close()
	local current
	for line in string.gmatch(content, "([^\n]*)\n?") do
		if string.find(line, "^Status:") then
			opennhrpstatus.value = string.match(line, ":%s*(%w+)")
		elseif string.find(line,"^Interface:") then
			local intf = string.match(line, ":%s*(%w+)")
			current = {}
			peers_list.value[intf] = peers_list.value[intf] or {}
			table.insert(peers_list.value[intf], current)
		elseif ( current ) and (line ~= "") then
			local name,val = string.match(line,"^(.-):%s?(.*)")
			if name and val then
				current[name] = cfe({value=val, label=name})
				if (type(descr[name]) == "table") then
					current[name].descr = descr[name][val]
				end
			end
		end
	end

	return cfe({ type="group", value={peers_list=peers_list, status=opennhrpstatus}, label="OpenNHRP Show Report" })
end

local function parseconfigfile(self, configfile)
	if fs.is_file(configfile) then
		configfile = fs.read_file(configfile)
	end

	-- Get the list of available interfaces
	local interfaces = self:new("alpine-baselayout/interfaces")
	local availableinterfaces = interfaces:read()
	local listinterfaces = {}
	local reverseinterfaces = {}
	for i,int in ipairs(availableinterfaces.value) do
		listinterfaces[#listinterfaces + 1] = int.value.name.value
		reverseinterfaces[int.value.name.value] = #listinterfaces
	end
	interfaces:destroy()

	local outgoinginterface = cfe({ type="select", label="Outgoing Interface", option=listinterfaces })
	local publishedinterfaces = cfe({ type="multi", value={}, label="Published Interfaces", option=listinterfaces })
	local peers = cfe({ type="list", value={}, label="Registered Peers", descr="protocol-address[/prefix] nbma-address" })
	local currentinterface = ""
	local words = {}
	for word in configfile:gmatch("%S+") do words[#words + 1] = word end
	for i,word in ipairs(words) do
		if word == "interface" then
			currentinterface = words[i+1]
		elseif word == "map" then
			if outgoinginterface.value ~= "" and outgoinginterface.value ~= currentinterface then
				outgoinginterface.errtxt = "Multiple outgoing interfaces not supported"
			else
				outgoinginterface.value = currentinterface
				peers.value[#peers.value + 1] = words[i+1] .. " " .. words[i+2]
			end
		elseif word == "shortcut-destination" then
			publishedinterfaces.value[#publishedinterfaces.value + 1] = currentinterface
		end
	end

	return cfe({ type="group", value={outgoinginterface=outgoinginterface, peers=peers, publishedinterfaces=publishedinterfaces}, label="OpenNHRP Config" })
end

local function generateconfigfile(config)
	local filelines = {}
	filelines[#filelines + 1] = "interface " .. config.value.outgoinginterface.value
	for i,value in ipairs(config.value.peers.value) do
		filelines[#filelines + 1] = "	map " .. value .. " register"
	end
	filelines[#filelines + 1] = "	shortcut"
	filelines[#filelines + 1] = "	redirect"
	filelines[#filelines + 1] = "	non-caching"
	filelines[#filelines + 1] = ""
	for i,value in ipairs(config.value.publishedinterfaces.value) do
		filelines[#filelines + 1] = "interface " .. value
		filelines[#filelines + 1] = "	shortcut-destination"
		filelines[#filelines + 1] = ""
	end

	return table.concat(filelines, "\n")
end

local function validateconfig(config)
	local success = true
	if not modelfunctions.validateselect(config.value.outgoinginterface) then
		success = false
	end
	if not modelfunctions.validatemulti(config.value.publishedinterfaces) then
		success = false
	end
	-- make sure don't try to publish the outgoing interface
	for i,value in ipairs(config.value.publishedinterfaces.value) do
		if value == config.value.outgoinginterface.value then
			success = false
			config.value.publishedinterfaces.errtxt = "Cannot publish outgoing interface"
			break
		end
	end
	for i,value in ipairs(config.value.peers.value) do
		if not validator.is_ipv4(value:match("[^%s/]+")) then
			success = false
			config.value.peers.errtxt = "Syntax error - invalid ip address"
			break
		elseif value:match("/(%d*)") and not validator.is_integer_in_range(value:match("/(%d*)"), 1, 31) then
			success = false
			config.value.peers.errtxt = "Syntax error - invalid prefix"
			break
		elseif string.find(value:match("%s(%S+)"), "[^%w.-]") then
			success = false
			config.value.peers.errtxt = "Syntax error - invalid domain name"
			break
		end
	end
	return success, config
end

local function validateconfigfile(self, configfile)
	local config = parseconfigfile(self, configfile.value.filecontent.value)
	local success, config = validateconfig(config)
	if not success then
		local errtxt = {}
		for name,value in pairs(config.value) do
			if value.errtxt then
				errtxt[#errtxt + 1] = name .. " - " .. value.errtxt
			end
		end
		if #errtxt then
			configfile.value.filecontent.errtxt = table.concat(errtxt, "\n")
		end
	end
	return success, configfile
end

-- ################################################################################
-- PUBLIC FUNCTIONS

function startstop_service(action)
	return modelfunctions.startstop_service(processname, action)
end

function getstatus()
	return modelfunctions.getstatus(processname, packagename, "Opennhrp Status")
end

function getshowreport()
	return opennhrpctl_show()
end

function getconfig(self)
	local config = parseconfigfile(self, configfile)
	local result, config = validateconfig(config)
	return config
end

function setconfig(self, config)
	local success, config = validateconfig(config)
	if success then
		fs.write_file(configfile, generateconfigfile(config))
	else
		config.errtxt = "Failed to set configuration"
	end
	return config
end

function getconfigfile(self)
	return modelfunctions.getfiledetails(configfile, nil, function(filedetails) return validateconfigfile(self, filedetails)end)
end

function setconfigfile(self, filedetails)
	return modelfunctions.setfiledetails(filedetails, {configfile}, function(filedetails) return validateconfigfile(self, filedetails)end)
end