module(..., package.seeall)

-- Load libraries
require("modelfunctions")
require("posix")
require("fs")
require("format")
require("date")
require("validator")

-- Set variables
local configfile = "/etc/rrdtool/acf-rrdtool.conf"
local graphpath = "/etc/rrdtool"
local databases = "/etc/rrdtool/databases"
local processname = "rrdtool"
local packagename = "rrdtool"
local header = "rrdtool"
local path="PATH=/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/sbin "

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

local function file_info ( path )
	local st = fs.stat(path)
	local size = st.size or "0"
	local lastmod = st.mtime or "---"
	return lastmod,size
end

local function list_files (path,search)
	local files = fs.find_files_as_array(search, path)

	local listed_files = {}

	-- Loop through each file and present its info
	for k,v in pairs(files) do
		-- Get info on this specific file and put it in a table
		local lastmod,size = file_info(v)
		local filename = cfe({ value=v, label="File name" })
		local filesize = cfe({ value=size, label="File size" })
		local mtime = cfe({ value=lastmod, label="File date" })
		table.insert ( listed_files , cfe({ type="group", value={filename=filename, filesize=filesize, mtime=mtime, label="File details"} }) )
	end
	table.sort(listed_files, function (a,b) return (a.value.filename.value < b.value.filename.value) end )
	return cfe({ type="list", value=listed_files, label="Log files" })

end

local function validfilename(path)
	local files = fs.find_files_as_array(nil, databases)

	for k,v in pairs(fs.find_files_as_array(".*graph",graphpath)) do
		table.insert(files,v)
	end
	for k,v in pairs(files) do
		if (v == path) then
			return true, tostring(path)
		end
	end
	return false, "Not a valid filename!"
end

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

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

function getstatus()
	return modelfunctions.getstatus(processname, packagename, header .. " status")
end

function getconfigfile()
	return modelfunctions.getfiledetails(configfile)
end

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

function getrrdlist()
	return list_files(databases)
end

function createnewrrd()
	local newdb = {}
		newdb.filename = cfe({label="Name",value="mydb.rrd",descr="The name of the RRD you want to create. RRD files should end with the extension .rrd. However, RRDtool will accept any filename."})
		newdb.start = cfe({label="Start",value="",descr="Specifies the time in seconds since 1970-01-01 UTC when the first value should be added to the RRD. RRDtool will not accept any data timed before or at the time specified.\
(Your system saids that your current time is '" .. tostring(os.time(os.date("*t"))) .. "' in the format you should specify above. The startvalue should be smaller than your current time.)\
(Default: now - 10s)"})
		newdb.step = cfe({label="Step",value="",descr="Specifies the base interval in seconds with which data will be fed into the RRD.\
(Default: 300)"})
		newdb.ds = cfe({label="Data store(s)",value="",descr="DS:ds-name:GAUGE | COUNTER | DERIVE | ABSOLUTE:heartbeat:min:max \
DS:ds-name:COMPUTE:rpn-expression",type="longtext"})
		newdb.rra = cfe({label="Round Robin Archive(s)",value="",descr="RRA:AVERAGE | MIN | MAX | LAST:xff:steps:rows",type="longtext"})
	return {value=newdb}
end

function remove_file(self, path, userid)
	local success = "Failed to delete file"
	local errtxt
	if not (fs.is_file(path)) then
		errtxt = "File doesn't exist!"
	elseif (validfilename(path)) then
		os.remove(path)
		success = "File Deleted"
	else
		errtxt = "Not a valid filename!"
	end
	return cfe({ value=success, label="Delete config file result", errtxt=errtxt })
end

function rrd_info(self, path, userid)
	local success, errtxt
	if (validfilename(path)) then
		local f = io.popen( "/usr/bin/rrdtool info ".. tostring(path) .. " 2>&1" )
		success = f:read("*a") or ""
		f:close()
	end
	return cfe({ value=success, label="rrdtool info ".. tostring(path) , errtxt=errtxt })
end

function savenewrrd(self, configfile, userid)
	path=tostring(databases).."/"..configfile.value.filename.value
	configfile.errtxt = "Failed to create file"
	local path = configfile.value.filename.value
	if not string.find(path, "/") then
		path = databases .. "/" .. path
	elseif not validator.is_valid_filename(path,databases) then
		configfile.value.filename.errtxt = "Not a valid path!\
If you specify path, it should be " .. tostring(databases) .."/"
		return configfile
	end
	if (posix.stat(path)) then
		configfile.value.filename.errtxt = "File already exists"
	elseif (#configfile.value.step.value > 0) and not tonumber(configfile.value.step.value) then
		configfile.value.step.errtxt = "Only numeric values!"
		return configfile
	elseif (#configfile.value.ds.value == 0) then
		configfile.value.ds.errtxt = "You need to specify at least one DS!"
		return configfile
	elseif (#configfile.value.rra.value == 0) then
		configfile.value.rra.errtxt = "You need to specify at least one RRA!"
		return configfile
	else
		local start,step
		if (#configfile.value.start.value > 0) then
			start = "--start " .. tostring(configfile.value.start.value) .. " "
		else
			start = ""
		end
		if (#configfile.value.step.value > 0) then
			step = "--step " .. tostring(configfile.value.step.value) .. " "
		else
			step = ""
		end
		local f = io.popen( "/usr/bin/rrdtool create ".. 
		  format.escapespecialcharacters(path) .. " " ..
		  format.escapespecialcharacters(start) ..
		  format.escapespecialcharacters(step) ..
		  tostring(string.gsub(format.dostounix(format.escapespecialcharacters(configfile.value.ds.value)),"\n", " \\\n")) .. " " ..
		  tostring(string.gsub(format.dostounix(format.escapespecialcharacters(configfile.value.rra.value)),"\n", " \\\n")) .. " 2>&1")
		success = f:read("*a") or ""
		f:close()
		configfile.errtxt = tostring(success)
	end

	return configfile
end

function list_graphs()
	local graphs = {}
	local files = fs.find_files_as_array(".*graph", graphpath)

	for k,v in pairs(files) do
		local filecontent = {}
		for kk,vv in pairs(fs.read_file_as_array(v)) do
			vv = string.gsub(vv,"\"", "")
			local delim = string.find(vv, "\=")
			if delim then
				filecontent[string.sub(vv,1,(delim-1))]=string.sub(vv,(delim+1),#vv)
			end
		end

		if not (filecontent.group) then
			filecontent.group = "General"
		end
		graphs[filecontent.group] = graphs[filecontent.group] or {}
			
		table.insert(graphs[(filecontent.group)],filecontent)
	end

	return graphs
end

function view_graph(self, graph_grp, graph_id)
	local general_settings = {
	  filenameextention=".png",
	  graph_width="800",
	  }

	local graphs = list_graphs()
	local settings = graphs[tostring(graph_grp)][tonumber(self.clientdata.id)]
	local filename = "/".. string.lower(tostring(graph_grp)).."_"..tostring(graph_id) .. 
	  (settings.filenameextention or ".png")
	settings.output = tostring(filename)

	--TODO: Loop the defaultsettings and put it in the settings table if there is missing some information
	
	local cmd = "/usr/bin/rrdtool graph /usr/share/acf/www" .. tostring(filename) .. " "

	cmd = cmd .. tostring(settings.value)
	settings.cmd_query = cmd
	local f = io.popen( tostring(cmd) .. " 2>&1" )
	settings.cmd_result = f:read("*a") or ""
	f:close()

	-- Display the image in it's original size (if possible)	
	settings.graph = {}
	settings.graph.width,settings.graph.height = string.match(settings.cmd_result, "^(%d+)x(%d+)")

	return settings 
end

function getgraphlist()
	return list_files(graphpath,".*graph")
end

function getgraphfile(path)
	if (path) and not (validfilename(path)) then
		path = nil
	end
	local filedetails = modelfunctions.getfiledetails(path)
	-- If we create a new file, we want to help the user to know what variables he should use
	if not (path) then
		filedetails.value.filecontent.value = [[label=Example name for this graph
group=General
descr=Some describing text that helps the user to know what this graph is all about
value=--start now-3600s --end now --width 680 --height 400 --step 300 DEF...
]]
	end
	local output = {value={filename=filedetails.value.filename,
	  filecontent=filedetails.value.filecontent,}}
--	output.value.filecontent.rows="30"	-- FIXME: For some reason I can't control the size of a textarea
	if not (path) then
		output.value.filename.errtxt=nil
	end
	return output
end

function set_filedetails (self, filedetails, userid)
	if filedetails.value.filename.value and (#filedetails.value.filename.value > 0) and not (string.match(filedetails.value.filename.value, ".*/$")) then
		if not (string.match(filedetails.value.filename.value, "^" .. graphpath)) then
			filedetails.value.filename.value = graphpath .. "/" .. string.gsub(filedetails.value.filename.value,"^.*/", "")
		end
		if not (string.match(filedetails.value.filename.value, "\.graph$")) then
			filedetails.value.filename.value = filedetails.value.filename.value .. ".graph"
		end

		filedetails = modelfunctions.setfiledetails(filedetails, getgraphlist)
	else
		filedetails.errtxt = "Failed to set file"
		filedetails.value.filename.errtxt = "You need to specify a valid filename!"
	end
	filedetails.value.filesize = nil
	filedetails.value.mtime = nil
	return filedetails
end

function setgraphfile(filedetails,file)
	return modelfunctions.setfiledetails(filedetails, {file})
end