feat(tui): implement SomaFM terminal radio player

somafm_tui/widgets/status.py

@@ -0,0 +1,90 @@
+"""One-line status / key hint bar."""
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, cast
+
+from rich.cells import cell_len
+from rich.console import RenderableType
+from rich.text import Text
+from textual.widget import Widget
+
+from .common import compact_count, state_glyph, truncate
+
+if TYPE_CHECKING:
+    from ..app import SomaFMApp
+
+HINTS_LONG = (
+    "SPACE pause  ↑↓ station  ENTER tune  +/- vol  f ★  / filter  "
+    "v visual  r refresh  ? help  q quit"
+)
+HINTS_MEDIUM = (
+    "space pause · ↑↓ station · enter tune · +/- vol · f ★ · / filter · ? help · q quit"
+)
+HINTS_SHORT = "↑↓ station · space play · ? help · q quit"
+
+
+class StatusBar(Widget):
+    can_focus = False
+
+    def render(self) -> RenderableType:
+        app = cast("SomaFMApp", self.app)
+        width = max(20, self.size.width)
+        glyph, colour = state_glyph(app.playing_state)
+        frame = app.spectrum.snapshot()
+        mpris = app.mpris.status_label
+        backend = app.player.backend or "no audio"
+        analyser = frame.label
+
+        listeners = ""
+        if app.current is not None and app.current.listeners:
+            listeners = f"♪ {compact_count(app.current.listeners)}  "
+        state = app.playing_state
+        volume = f"vol {app.volume:>3}%"
+
+        # From most to least informative; pick the first combination that fits.
+        right_variants = (
+            f"{state}  {listeners}{volume}  {backend}  mpris {mpris}  {analyser}",
+            f"{state}  {volume}  {analyser}",
+            f"{state}  {volume}",
+            volume,
+        )
+        options = (
+            (HINTS_LONG, right_variants[0]),
+            (HINTS_LONG, right_variants[1]),
+            (HINTS_MEDIUM, right_variants[0]),
+            (HINTS_MEDIUM, right_variants[1]),
+            (HINTS_SHORT, right_variants[1]),
+            (HINTS_SHORT, right_variants[2]),
+            (HINTS_SHORT, right_variants[3]),
+        )
+
+        chosen: tuple[int, str, str] | None = None
+        for hint, right_text in options:
+            right_width = cell_len(glyph) + 1 + cell_len(right_text)
+            if cell_len(hint) + right_width + 2 <= width:
+                chosen = (right_width, right_text, hint)
+                break
+
+        if chosen is None:
+            right_text = right_variants[-1]
+            right_width = cell_len(glyph) + 1 + cell_len(right_text)
+            if width <= right_width + 2:
+                line = Text(no_wrap=True)
+                line.append(
+                    truncate(f"{glyph} {right_text}", width), style="dim"
+                )
+                return line
+            chosen = (right_width, right_text, "")
+
+        right_width, right_text, hint = chosen
+        left_width = max(0, width - right_width - 2)
+        left = app.notice or hint
+        left_style = "italic yellow" if app.notice else "dim"
+
+        line = Text(no_wrap=True)
+        line.append(truncate(left, left_width), style=left_style)
+        line.append(" " * max(0, width - left_width - right_width))
+        line.append(f"{glyph} ", style=f"bold {colour}")
+        line.append(right_text, style="dim")
+        return line