"""
haTerm - v0.1
(c) Sophia Schmidhofer

haTerm is a Terminal Based hafas client, using the ivb endpoint.
Prompt_toolkit (https://github.com/prompt-toolkit/python-prompt-toolkit) will be used to render a terminal user interface (TUI).
The application will provide routing information and station departures/arrivals.

Route planning UI.

Wrapped in a function so it can be launched from `main.py` with a shared
`HafasClient` instance from `backend.py`.

Note: This module is a minimal TUI stub. Many features are not implemented
yet (station lookup, route rendering). Add TODOs where appropriate.
"""

import time
from prompt_toolkit import Application
from prompt_toolkit.buffer import Buffer
from prompt_toolkit.layout.containers import HSplit, VSplit, Window
from prompt_toolkit.layout.controls import BufferControl
from prompt_toolkit.layout.layout import Layout
from prompt_toolkit.key_binding import KeyBindings

import backend


def run_route_planning(hafas: backend.HafasClient | None = None):
    """Run the route planning TUI.

    Parameters:
    - hafas: optional shared HafasClient instance. If omitted, a new one is
      created. Prefer passing the shared client from `main.py`.
    """
    if hafas is None:
        hafas = backend.HafasClient()

    # TODO: integrate actual station search + routing using `hafas`.
    kb = KeyBindings()
    startBuffer = Buffer()
    endBuffer = Buffer()

    root_container = HSplit(children=[
        HSplit(children=[
            Window(content=BufferControl(buffer=startBuffer, focusable=True)),
            Window(width=1, char='-', style="fg:#2A71D5"),
            Window(content=BufferControl(buffer=endBuffer, focusable=True))
        ]),
        Window(height=1, char=' ', style="bg:#2A71D5 fg:black"),
    ])

    layout = Layout(root_container)
    app = Application(layout=layout, key_bindings=kb, full_screen=True)

    try:
        app.run()
    except KeyboardInterrupt:
        # graceful exit on Ctrl-C
        return