import 'package:flutter/widgets.dart';

/// A full color palette for one selectable app theme. Immutable; the app swaps
/// which instance is [TimbreColors._active] when the user changes theme.
class TimbrePalette {
  const TimbrePalette({
    required this.brightness,
    required this.background,
    required this.surface,
    required this.foreground,
    required this.dimmed,
    required this.border,
    required this.borderActive,
    required this.accentDefault,
  });

  final Brightness brightness;
  final Color background;
  final Color surface;
  final Color foreground;
  final Color dimmed;
  final Color border;
  final Color borderActive;
  final Color accentDefault;

  /// The original near-black, low-contrast theme (the app's default).
  static const TimbrePalette dark = TimbrePalette(
    brightness: Brightness.dark,
    background: Color(0xFF1A1A1A),
    surface: Color(0xFF161616),
    foreground: Color(0xFFD4D0C8),
    dimmed: Color(0xFF5A5858),
    border: Color(0xFF252525),
    borderActive: Color(0xFF3A3A3A),
    accentDefault: Color(0xFFFF8C00),
  );

  /// A light theme: lavender canvas, slightly-deeper-lavender panels, deep-indigo
  /// text and accent. The accent is locked to [accentDefault] while this theme
  /// is active (see `main.dart`).
  static const TimbrePalette lavender = TimbrePalette(
    brightness: Brightness.light,
    background: Color(0xFFD3D3FF), // lavender canvas (primary)
    surface: Color(0xFFC6C6F4), // slightly darker lavender panels
    foreground: Color(0xFF2E2A45), // deep-indigo text
    dimmed: Color(0xFF6A6688), // muted indigo-grey
    border: Color(0xFFB9B9E8), // deeper-lavender hairline
    borderActive: Color(0xFF2E2A45), // accent-toned active border
    accentDefault: Color(0xFF2E2A45), // deep indigo (accent)
  );
}

/// Design tokens mirroring Timbre's `dynamic`/`static` theme defaults
/// (see timbre `docs/sample-config.toml`, `theme.rs`, `color.rs`).
///
/// The palette is intentionally near-black and low-contrast in the default
/// theme; the *accent* is the one lively color and, in the `dynamic` theme, is
/// extracted live from the current album art. The base colors are no longer
/// compile-time constants — they resolve through [_active] so a user-selected
/// theme (see [TimbrePalette]) recolors the whole app. `applyPalette` is called
/// once per build by `TimbreApp` before the theme is built.
class TimbreColors {
  const TimbreColors._();

  static TimbrePalette _active = TimbrePalette.dark;

  /// Swap the active palette. Called by `TimbreApp.build` from the persisted
  /// theme setting; a re-keyed subtree remount then re-reads these getters.
  static void applyPalette(TimbrePalette p) => _active = p;

  /// Brightness of the active theme (drives `ThemeData`/`ColorScheme`).
  static Brightness get brightness => _active.brightness;

  /// App canvas.
  static Color get background => _active.background;

  /// Panel/surface fill (slightly offset from the canvas).
  static Color get surface => _active.surface;

  /// Primary text.
  static Color get foreground => _active.foreground;

  /// Secondary/muted text.
  static Color get dimmed => _active.dimmed;

  /// Hairline borders (inactive).
  static Color get border => _active.border;

  /// Hairline borders when a pane is focused.
  static Color get borderActive => _active.borderActive;

  /// Default accent when no art-derived accent applies.
  static Color get accentDefault => _active.accentDefault;
}

/// Spacing scale — dense, "player as instrument" rather than airy mobile cards.
class TimbreSpacing {
  const TimbreSpacing._();

  static const double xs = 2;
  static const double sm = 4;
  static const double md = 8;
  static const double lg = 12;
  static const double xl = 16;

  /// Minimum touch target per Apple/Material guidance — keep rows dense
  /// visually but pad hit areas to at least this.
  static const double minTouchTarget = 44;
}