language-server.jl

# Structure
         
# client sends    :  message::String          
# JSON.parse()    :  message::String              -> message_json::Dict
# Request()       :  message_json::Dict           -> req::Request{method,parametertype}
# Respond{m,pt}() :  req::Request{m,pt}           -> resp::Response{m,returntype}
# JSON.json()     :  resp::Response{m,returntype} -> retmessage::String
# return          :  retmessage::String

# A whole load of these for all parameter structures listed in the language-server protocol
type Position
    line::Int
    character::Int
end
Position(d::Dict) = Position(d["line"],d["character"])


abstract Method
abstract hover <: Method
type Hover <: Response
    contents::String
    range::Range #?
end

type Request{m<:Method,T}
    id::Int
    params::T
end

function Request(d::Dict)
    m = d["method"]
    if m=="textDocument/hover"
        return Request{hover,TextDocumentPositionParams}(d["id"],TextDocumentPositionParams(d["params"]))
    end
end

function Respond(r::Request{hover,TextDocumentPositionParams})
    d = documents[r.params.textDocument.uri]
    cnt=0
    s=1
    while cnt<r.params.position.line-1 
        cnt+=1
        s=search(d,'\n',s)+1
    end
    line = d[s:search(d,'\n',s)] 
    word = getfullname(line,r.params.position.character)
    try
        d = Docs.doc(getfield(Main,Symbol(word)))
        return Response{hover,Hover}(r.id,Hover(d,Range()))
    catch err
        return Response{hover,Exception}(r.id,err)
    end
end





message = read_transport_layer(conn)
message_json = JSON.parse(message)
request = Request(message_json)
response = Respond(request)
write_transport_layer(conn,response)