store.lua

local STORE_URL = "QV6xpc1r";
local args = { ... };

local function help()
    print("Usage: pkgmanager <program_name>")
end

local function loadStore()
    local pastebin = "https://pastebin.com/raw/";
    local response, error, fail = http.get(pastebin .. STORE_URL);

    if response == nil then
        return nil, error, fail;
    end

    local file = response.readAll();
    response.close();

    print(file);

    local storeTable = textutils.unserialiseJSON(file);

    return storeTable
end

local function downloadProgram(programName, store)
    local program = store[programName];

    if not program then
        print("Error: non-existant program '"..programName.."'.");
        print("Valid options are:");

        for programName, _ in pairs(store) do
            print("- " .. programName);

        end
    end

    print("Installing program!");
end

local function main()
    if #args == 0 then
        print("Error: No argument supplied. Please specify which program to install.");
        help();
        return;
    end

    local storeTable, error, fail = loadStore();

    if not storeTable then
        print(error);
        return;
    end

    downloadProgram(args[1], storeTable);
end

main();