local fs=require("filesystem")

local lib={}

local rules_path="/etc/udev/rules.d/"
local auto_rules="autogenerated.lua"

local function fs_key(dir,filename)
local long_name=dir..'/'..filename
local segments=fs.segments(long_name)
local result='/'..table.concat(segments,'/')
return result
end

function lib.loadRules(root_dir)
checkArg(1,root_dir,"string","nil")
root_dir=(root_dir or rules_path)
lib.rules={}
lib.rules[fs_key(root_dir,auto_rules)]={}

for file in fs.list(root_dir)do
if file:match("%.lua$")then
local path=fs_key(root_dir,file)
local file_handle=io.open(path)
if file_handle then
local load_rule=load("return {"..file_handle:read("*a").."}")
file_handle:close()
if load_rule then
local ok,rule=pcall(load_rule)
if ok and type(rule)=="table"then
local irule={}
lib.rules[path]=irule
for _,v in ipairs(rule)do
if type(v)=="table"then
table.insert(irule,v)
end

end
end
end
end
end
end
end

function lib.saveRule(rule_set,path)
checkArg(1,rule_set,"table")
checkArg(2,path,"string")
local file=io.open(path,"w")
if not file then return end
for index,irule in ipairs(rule_set)do
file:write(require("serialization").serialize(irule),",\n")
end
file:close()
end

function lib.saveRules(rules)
for path,rule_set in pairs(rules)do
lib.saveRule(rule_set,path)
end
end

local function getIRule(proxy)
checkArg(1,proxy,"table")
for path,rule_set in pairs(lib.rules)do
for index,irule in ipairs(rule_set)do
if irule.address==proxy.address then
return irule,index,rule_set,path
end
end
end
end

function lib.getDeviceLabel(proxy)
local irule=getIRule(proxy)
if irule and irule.label then
return irule.label
elseif proxy.getLabel then
return proxy.getLabel()
end
end

function lib.setDeviceLabel(proxy,label)
local irule,index,rule_set,path=getIRule(proxy)
if not irule then

if proxy.setLabel then
return proxy.setLabel(label)
end
path=fs_key(rules_path,auto_rules)
rule_set=lib.rules[path]
index=#rule_set+1
irule={address=proxy.address}
table.insert(rule_set,irule)
end
irule.label=label
lib.saveRule(rule_set,path)
end

return lib