class MainActivity : AppCompatActivity(), KodeinAware {

    override val kodein by kodein()
    private var notesAdapter: NotesAdapter ?= null
    private var mLayout : LinearLayoutManager ?= null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        ft_btn.setOnClickListener {
            val intent = Intent(this, AddNoteActivity::class.java)
            startActivity(intent)
        }

        initRecyclerview()

        val db = NoteRoomDatabase(this)
        val repo = NotesRepository(db)
        val factory = NotesViewModelFactory(repo)

        val notesViewModel : NotesViewModel = ViewModelProvider(this, factory).get(NotesViewModel::class.java)
        notesViewModel.getAllNotesFromDB().observe(this, Observer {
            notesAdapter?.submitList(it)
        })
    }

    private fun initRecyclerview(){
        recyclerView.setHasFixedSize(true)
        mLayout = LinearLayoutManager(this)
        recyclerView.layoutManager = mLayout
        recyclerView.adapter = notesAdapter
    }
}

class AddNoteActivity : AppCompatActivity() {
    private var notesViewModel: NotesViewModel?= null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_add_note)

        btn_save_note.setOnClickListener {
            saveNotesToDB()
            val intent = Intent(this, MainActivity::class.java)
            startActivity(intent)
        }
    }

    private fun saveNotesToDB(){
        val title = et_title.toString().trim()
        val note = et_note_body.toString().trim()
        when {
            title.isEmpty() -> {
                et_title.error = "Title cannot be blank!"
                et_title.requestFocus()
            }
            note.isEmpty() -> {
                et_note_body.error = "Body cannot be blank!"
                et_note_body.requestFocus()
            }
            else -> {
                val notes = Note(title, note)
                notesViewModel?.insertNotesToDB(notes)
            }
        }
    }

initRecyclerView()