api/app

function new(dir)
  local App = {
    Running = true,
    EventHandler = events.createHandler()
  }

  if dir then
    App.Directory = dir
    App.Manifest = data.load(dir..".manifest")
    App.Id = string.match(dir, "[^/]-$")

    function App:download(code, name)
      name = name or code
      pastebin.get(code, self.Directory.."/"..name)
    end

    function App:resolve(path)
      return self.Directory.."/"..path
    end

    function App:open(path)
      return fs.open(self.Directory.."/"..path)
    end

    function App:delete(path)
      fs.delete(self.Directory.."/"..path)
    end

    function App:load(path)
      return data.load(self.Directory.."/"..path)
    end

    function App:save(path, tbl)
      return data.save(self.Directory.."/"..path, tbl)
    end

    function App:handleUninstall(id)
      if id ~= self.Id then return end
      self:stop()
    end

    App.EventHandler:connect("uninstall_app", function(...) App:handleUninstall(...) end)
  end

  function App:stop()
    self.Running = false
  end

  function App:draw() end
  function App:stopped() end

  function App:start()
    self.Running = true
    while self.Running do
      self:draw()
      self.EventHandler.update()
    end
    if self.Manifest then os.queueEvent("app_closed", self.Id) end
    self:stopped()
  end

  App.EventHandler:connect("terminate", function() App:stop() end)

  return App
end

function dir(id)
  local d = "/appdata/"..id
  return d, fs.exists(d)
end

function install(code)
  local apps = data.load("/.apps")
  local d = dir(code)
  fs.delete(d..".manifest")
  pastebin.get(code, d..".manifest")
  local m = data.load(d..".manifest")
  for file,data in pairs(m.Files) do
    local p = d.."/"..file
    fs.delete(p)
    pastebin.get(data.Code, p)
  end
  apps[code] = {1,2,-1}
  data.save("/.apps", apps)
  os.queueEvent("update_apps")
end

function uninstall(id)
  local apps = data.load("/.apps")
  local d = dir(id)
  fs.delete(d)
  fs.delete(d..".manifest")
  apps[id] = nil
  data.save("/.apps", apps)
  os.queueEvent("uninstall_app", id)
  os.queueEvent("update_apps")
end

function update(code)
  local d = dir(code)
  local m = data.load(d..".manifest")
  fs.delete(d..".manifest")
  pastebin.get(code, d..".manifest")
  local nm = data.load(d..".manifest")
  for file,data in pairs(nm.Files) do
    if not m.Files[file] or m.Files[file].Version ~= data.Version then
      local p = d.."/"..file
      fs.delete(p)
      pastebin.get(data.Code, p)
    end
    m.Files[file] = nil
  end
  for file,data in pairs(m.Files) do fs.delete(d.."/"..file) end
  return nm
end

function list()
  return data.load("/.apps")
end