(:~ 
 Manage a store for websocket info.It is named as the websocket $sid
:)
module namespace storex = 'storex';

(: cache has index :)
declare variable $storex:rules:={
 "doc":{
   "description":"A text document" 
   },

 "parse":{
    "description":"XML parse tree" ,
    "depends":"text",
    "calc": "xqparse"
 },

 "symbols":{
   "description":"LSP symbols",
   "depends":"parse",
   "calc": "symbols"
 }

};
(:~ in store $sid, and key $uri get value of $property  :)
declare function storex:get($uri as xs:string,$sid as xs:string,$property as xs:string)
{
let $id:=storex:id($uri,$sid )
let $property:=storex:property($property)
return store:get($property || $id,$sid) 
       otherwise error(xs:QName("storex:get"),`property unknown: '{$property}'`)
};

(:~ get value of $property  :)
declare function storex:put($uri as xs:string,
                           $sid as xs:string,
                           $property as xs:string,
                           $value as item())
{
let $id:=storex:id($uri,$sid ,true() )
let $property:=storex:property($property)
return store:put($property || $id,$value,$sid) 
};

(:~ key for $sid and $uri, error if not found unless $add.
if $add then add entry for uri
  :)
declare function storex:id($uri as xs:string,$sid as xs:string,$add as xs:boolean:=false())
{
let $index:=store:get-or-put("index",fn(){{}},$sid)
return  if(map:contains($index,$uri))
        then $index?uri
        else if($add)
             then let $id:=random:uuid()
                  return ($id,store:put("index",map:put($index,$uri,$id),$sid))  
             else error(xs:QName("storex:get"),`Uri not found: '{$uri}'`)
};

(:~ key for $sid and $uri, error if not found unless $add.
if $add then add entry for uri
  :)
declare function storex:property($property as xs:string)
as xs:string
{
  if(map:contains($storex:rules,$property))
  then $property
  else error(xs:QName("storex:get"),`property not in rules: '{$property}'`)
};