-- Websocker: Used for connection between the controle webserver and Units(computers)
Core = {};
Core.__index = Core;

function Core:new()
    local self = setmetatable({}, Core);
    return self;
end

function Core:connect()
    if not self then
        error("No instance!")
    end

    ws, err = assert(http.websocket("ws://192.168.5.162:8080"));

    if not ws then
        term.setTextColor(colors.red);
        print(err);
        term.setTextColor(colors.white);
    end

    self.ws = ws;
end

function Core:send(package)
    if not self then
        error("No instance!")
    end

    if not package then
        return false, "Missing package";
    end

    if not self.ws then
        return false, "Websocket not initiated";
    end

    self.ws.send(textutils.serialiseJSON(package));
end

function Core:read()
    if not self then
        error("No instance!")
    end

    if not self.ws then
        return false, "Websocket not initiated";
    end

    local data, success = self.ws.receive()

    return true, textutils.unserialiseJSON(data)
end

function Core:download(file)
    if not self then
        error("No instance!")
    end

    if not self.ws then
        return false, "Websocket not initiated";
    end

    self:send({type = "REQUEST_FILE_INFO", file = file});

    local success, data = self:read();

    if not success then
        return false, "Failed to read: "..data;
    end

    if not data.type then
        return false, "Invalid package: "..textutils.serialiseJSON(data);
    end

    if not (data.type == "FILE_INFO") then
        return false, "Invalid package type: "..textutils.serialiseJSON(data);
    end

    if not data.exists then
        return false, "File is missing from server"
    end

    self:send({type = "REQUEST_FILE_DATA", file = file})

    local success, data = self:read();

    if not success then
        return false, "Failed to read: "..data;
    end

    if not data.type then
        return false, "Invalid package: "..textutils.serialiseJSON(data);
    end
    
    if not data.type == "FILE_DATA"  then
        return false, "Invalid type: "..textutils.serialiseJSON(data)
    end

    if fs.exists(file) then
        fs.delete(file);
    end

    local fileStream = io.open(file, "w");

    if not fileStream then
        return false, "Failed to open fileStream"
    end

    fileStream:write(data.data);
    fileStream:close();

    return true, "Success"
end

function Core:disconnect()
    if not self then
        return "Not instance"
    end

    if not self.ws then
        return "Not initilized"
    end

    self.ws.close();
end