"""Header: logo, clock and a live ticker."""

from __future__ import annotations

from typing import TYPE_CHECKING, cast

from rich.cells import cell_len
from rich.console import Group, RenderableType
from rich.text import Text
from textual.widget import Widget

from .common import (
    SPECTRUM_STOPS,
    clock_time,
    date_label,
    gradient,
    marquee,
    state_glyph,
)

if TYPE_CHECKING:
    from ..app import BeefyPlayerApp

LOGO = (
    "▄▀▀▀ ▄▀▀▄ █▄ ▄█ ▄▀▀▄",
    "▀▀▀▄ █  █ █ █ █ █▀▀█",
    "▄▄▄▀ ▀▄▄▀ █   █ █  █",
)

MIDDLE = ("SOMA FM RADIO", "LISTENER SUPPORTED", "SAN FRANCISCO")


class HeaderBar(Widget):
    can_focus = False

    def render(self) -> RenderableType:
        app = cast("BeefyPlayerApp", self.app)
        width = max(24, self.size.width)
        height = max(1, self.size.height)
        state = app.playing_state
        glyph, colour = state_glyph(state)

        logo_width = max(cell_len(row) for row in LOGO)
        middle_width = max(cell_len(row) for row in MIDDLE)
        right = (clock_time(), date_label(), f"vol {app.volume}%")
        right_width = max(cell_len(item) for item in right)

        show_middle = width >= logo_width + middle_width + 8
        show_right = width >= logo_width + right_width + 8
        if show_middle and show_right:
            show_middle = width >= logo_width + 4 + middle_width + 2 + right_width

        lines: list[Text] = []
        for index, row in enumerate(LOGO):
            line = Text(no_wrap=True)
            for column, char in enumerate(row):
                position = (
                    column / max(1, logo_width - 1) + index * 0.055
                ) % 1.0
                line.append(
                    char, style=f"bold {gradient(SPECTRUM_STOPS, position)}"
                )
            if show_middle:
                line.append(" " * 4)
                middle = MIDDLE[index]
                line.append(middle, style="dim")
                # Keep the right block on one column even though the middle
                # lines differ in length ("SOMA FM RADIO" is shorter than
                # "LISTENER SUPPORTED").
                line.append(" " * max(0, middle_width - cell_len(middle)))
            if show_right:
                used = logo_width
                if show_middle:
                    used += 4 + middle_width
                # Right-align the block *and* every item inside it: the clock,
                # the date and the volume each keep their own length, so pad
                # the shortest ones instead of left-aligning the whole block.
                pad = max(1, width - used - right_width)
                item = right[index]
                line.append(" " * pad)
                line.append(" " * max(0, right_width - cell_len(item)))
                style = "bold" if index == 0 else "dim"
                line.append(item, style=style)
            lines.append(line)

        if height >= 4:
            ticker = Text(no_wrap=True)
            prefix = f"{glyph} {state.upper():<8}  "
            ticker.append(prefix, style=f"bold {colour}")
            station = app.current
            if app.notice:
                text = app.notice
                text_style = "italic yellow"
            elif station is not None:
                song = station.now_playing
                if song is not None:
                    text = f"{station.title}  ·  {song.display_artist} — {song.display_title}"
                else:
                    text = f"{station.title}  ·  {station.description}"
                text_style = ""
            else:
                text = "Pick a station — press enter to tune in"
                text_style = "italic dim"
            ticker.append(marquee(text, max(4, width - cell_len(prefix))), style=text_style)
            lines.append(ticker)

        return Group(*lines[:height])