tui.py

#!/usr/bin/env python3

import urwid
from typing import *


GENERATE = False

class Grid(urwid.Pile):
  def __init__(self, rows: int, cols: int, cellSize: int = 7):
    self.cellsEditor = [urwid.Edit("", align="center") for i in range(rows*cols)]
    self.__rows = rows
    self.__cols = cols

    div = urwid.Divider()

    super(Grid, self).__init__([
      urwid.Columns(
        [div] +
        [
          (cellSize, urwid.LineBox(self.cellsEditor[r*cols+c])) for c in range(cols)
        ] +
        [div]
      ) for r in range(rows)
    ])
  
  
  def get_text(self, r: int, c: int) -> str:
    return self.cellsEditor[r * self.__cols + c].get_text()

class FocusManager:
  def __init__(self, frame: urwid.Frame):
    self.frame = frame

  def __call__(self, input: str) -> bool:
    if input == 'tab':
      self.frame.set_focus(
        "footer" if self.frame.get_focus() == "body"
        else "body"
      )
      return True
    return False


def onExitClick(button: urwid.Button) -> NoReturn:
  raise urwid.ExitMainLoop()

def onGenerateClick(button: urwid.Button) -> NoReturn:
  global GENERATE
  GENERATE = True
  raise urwid.ExitMainLoop()

def startInteractiveScreen(rows: int, cols: int) -> None:
  headerTxt = urwid.Text(
    u"Fill the matrix with coefficients or scalars by moving with arrow keys.\n"
    "Click on GENERATE to quit this interactive screen and print the result on stdout.\n"
    "Use TAB to change focus."
  )

  exitButton = urwid.Button(u"EXIT")
  urwid.connect_signal(exitButton, "click", onExitClick)
  
  generateButton = urwid.Button(u"GENERATE")
  urwid.connect_signal(generateButton, "click", onGenerateClick)

  div = urwid.Divider()
  buttonsList = urwid.Columns([
    div,
    (8, exitButton),
    (5, div),
    (12, generateButton)
  ])

  grid = Grid(rows, cols)
  frame = urwid.Frame(urwid.Filler(grid), header=headerTxt, footer=buttonsList, focus_part="body")

  focusManager = FocusManager(frame)
  urwid.MainLoop(frame, unhandled_input = focusManager).run()

  if GENERATE:
    return [
      editor.get_text()[0] if editor.get_text()[0] != "" else "0" for editor in grid.cellsEditor
    ]

if __name__ == "__main__":
  print(startInteractiveScreen(3, 4))