from threading import Thread
from typing import List, Dict

from asciimatics.exceptions import NextScene
from asciimatics.widgets import Layout, Button, Divider, Label

from ..operation_strings import descriptions as op_desc
from ..utils import generic_handle_stream_response
from .CeoFrame import CeoFrame
from .TUIStreamResponseHandler import TUIStreamResponseHandler


class TransactionView(CeoFrame):
    def __init__(self, screen, width, height, model):
        super().__init__(
            screen, height, width, model, 'Transaction',
            on_load=self._txnview_on_load, title='Running Transaction',
        )
        # map operation names to label widgets
        self._labels = {}

    def _add_buttons(self):
        layout = Layout([100])
        self.add_layout(layout)
        layout.add_widget(Divider())

        layout = Layout([1, 1])
        self.add_layout(layout)
        self._next_btn = Button('Next', self._next)
        layout.add_widget(self._next_btn, 1)

    def _add_blank_line(self):
        self._op_layout.add_widget(Label(''), 0)
        self._op_layout.add_widget(Label(''), 2)

    def _txnview_on_load(self):
        self._op_layout = Layout([12, 1, 10])
        self.add_layout(self._op_layout)
        # store the layouts so that we can re-use them when the screen
        # gets resized
        for _ in range(2):
            self._add_blank_line()
        for operation in self._model.operations:
            desc = op_desc[operation]
            self._op_layout.add_widget(Label(desc + '...', align='>'), 0)
            desc_label = Label('', align='<')
            self._op_layout.add_widget(desc_label, 2)
            self._labels[operation] = desc_label
        self._add_blank_line()
        # this is the where success/failure messages etc. get placed
        self._msg_layout = Layout([100])
        self.add_layout(self._msg_layout)
        # fill up the rest of the space
        self.add_layout(Layout([100], fill_frame=True))

        self._add_buttons()
        self.fix()
        Thread(target=self._do_txn).start()

    def _do_txn(self):
        resp = self._model.deferred_req()
        handler = TUIStreamResponseHandler(
            model=self._model,
            labels=self._labels,
            msg_layout=self._msg_layout,
            txn_view=self,
        )
        data = generic_handle_stream_response(resp, self._model.operations, handler)
        self.write_extra_txn_info(data)

    # to be overridden in child classes if desired
    def write_extra_txn_info(self, data: List[Dict]):
        pass

    def enable_next_btn(self):
        self._next_btn.disabled = False
        # If we don't reset, the button isn't selectable, even though we
        # enabled it.
        # We don't want to reload, though (which reset() will trigger).
        self.skip_reload = True
        self.reset()

    def _next(self):
        self._model.reset()
        raise NextScene('Welcome')