/// Ported from `com.rippr.ui.theme.RipprTheme`.
///
/// Dark-only by design for a pocketed ride -- read at a glance, in a pocket-glance, at
/// night as much as in daylight. V3-05 adds [ripprMountedTheme], a deliberate exception
/// for the one screen that is actually looked at continuously, in direct daylight, behind
/// a visor -- where the dark ground loses to glare instead of helping.
library;

import 'package:flutter/material.dart';

// UI-08: "Modern Professional Dark", the design system actually backing every fetched
// Stitch mockup (confirmed by hex-matching, not by trusting the project's declared
// default theme — see docs/design/stitch-export/README.md). This supersedes V3-16's
// safety-orange identity outright, not an extension of it. Full spec:
// docs/design/stitch-export/design-system-modern-professional-dark.md.
//
// `surface-main` (#0a0a0c), not the spec's plain `background`/`surface` (#131313), is
// used as the app ground: the spec's own prose calls out #0a0a0c as *the* background,
// with #131313 one step up for a mid-level surface and #16161a another step up for cards
// — a three-step stack, not two.
const _ground = Color(0xFF0A0A0C);
const _surfaceMid = Color(0xFF131313);
const _ink = Color(0xFFE5E2E1);
const _outline = Color(0xFF8B919F);
const _danger = Color(0xFFFFB4AB);

/// Professional Blue. The soul of the interface per the design system's own doc —
/// primary buttons, the active nav indicator, the user's own location dot, and (via
/// `RideMap`'s speed gradient) the accent end of the live-path colouring. Replaces
/// safety-orange as *the* accent everywhere; the app's existing convention of leaving
/// headline figures (`BigStat`) in plain ink and reserving colour for `StatRow`'s
/// `reference` values is unchanged by this ticket.
const _primary = Color(0xFF4090FE);

/// UI-08 decision (the design system doesn't prescribe this split itself): reference
/// readings (a max, an average) get the warm tertiary orange, never the live figure,
/// which stays [_primary]. Inverted from V3-16 (blue was the reference colour there)
/// because blue is now the primary/live colour — a same-hue reference tone would have
/// been visually indistinguishable from the live one it exists to be told apart from.
const _referenceOrange = Color(0xFFFFB68C);

const ripprColors = ColorScheme.dark(
  primary: _primary,
  onPrimary: Color(0xFF002F64),
  secondary: Color(0xFFAEC7F6),
  tertiary: _referenceOrange,
  onTertiary: Color(0xFF532200),
  // UI-05: explicit rather than left to `ColorScheme.dark`'s own M3 tonal-palette
  // derivation -- the Map HUD's Pause/Stop control bar needs to match the design
  // system's literal `tertiary-container`/`error-container` tokens exactly, not
  // whatever a generated tonal palette happens to compute from `tertiary`/`error` alone.
  tertiaryContainer: Color(0xFFE3711F),
  onTertiaryContainer: Color(0xFF481D00),
  surface: _surfaceMid,
  onSurface: _ink,
  surfaceContainerHighest: Color(0xFF353534),
  onSurfaceVariant: Color(0xFFC1C6D5),
  outline: _outline,
  // UI-03: the design system's own `outline-variant` token -- a subtler line than
  // `outline` itself, for a `GlassPanel`'s 1px border and a `FloatingPill`'s dividers,
  // where a full-strength outline colour would read as a hard edge rather than a
  // barely-there seam between tonal layers.
  outlineVariant: Color(0xFF414753),
  error: _danger,
  onError: Color(0xFF690005),
  errorContainer: Color(0xFF93000A),
  onErrorContainer: Color(0xFFFFDAD6),
);

/// The near-black ground the whole app sits on.
const ripprBackground = _ground;

/// Cards and modals — one step up from [ripprColors]'s `surface`, per the design
/// system's three-level stack ("Surface Strategy": base darkest, cards a step lighter).
/// Exposed separately because `ColorScheme` has no fourth surface slot for it that isn't
/// already claimed by `surfaceContainerHighest` (reserved here for the selected/
/// highlighted state, not the resting card colour).
const ripprCardColor = Color(0xFF16161A);

/// Shape spec: "Rounded (Level 2)" — small components (buttons, inputs) get 8px, large
/// containers (cards, modals) get 16px. Two constants, not a single "roundness" figure,
/// because the spec explicitly gives them different values.
const double ripprRadiusSmall = 8.0;
const double ripprRadiusLarge = 16.0;

ThemeData ripprTheme() {
  final base = ThemeData(
    colorScheme: ripprColors,
    useMaterial3: true,
    scaffoldBackgroundColor: _ground,
  );

  return base.copyWith(
    // Compose's `Surface` was load-bearing, not decoration: it set `LocalContentColor`.
    // Without it, any Text that did not name a colour fell back to black — invisible on
    // this near-black ground, and **no test caught it; only a screenshot did**.
    //
    // Flutter's equivalent exposure is the default text colour. Setting it explicitly
    // here, rather than relying on a wrapping widget, means the failure cannot recur by
    // someone removing a container.
    // UI-08: the design system specifies Inter exclusively. Not switched to here --
    // naming a fontFamily with no matching asset bundled would silently fall back to
    // the platform default (Roboto), the exact class of invisible failure the bodyColor
    // fix below exists to prevent. Bundling the actual font files (or a vetted offline
    // build of the google_fonts package) is left as a deliberate follow-up rather than
    // shipping a fontFamily string that doesn't resolve to anything.
    textTheme: base.textTheme.apply(bodyColor: _ink, displayColor: _ink),
    appBarTheme: const AppBarTheme(
      backgroundColor: _ground,
      foregroundColor: _ink,
      elevation: 0,
    ),
    cardTheme: const CardThemeData(
      color: ripprCardColor,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.all(Radius.circular(ripprRadiusLarge)),
      ),
    ),
    dividerTheme: const DividerThemeData(color: Color(0xFF2D3037), space: 1),
  );
}

// V3-05: mounted colours. Near-white ground, near-black ink -- the inverse tradeoff from
// the pocketed theme above. Read against a visor in direct daylight, a dark ground loses
// to glare in a way a dark theme never has to answer for at a pocket glance.
const _mountedGround = Color(0xFFF5F3EF);
const _mountedInk = Color(0xFF12100D);
const _mountedAccent = Color(0xFFD84315);

// V3-16: the same instrument/reference split as the pocketed theme, darkened enough to
// hold WCAG AA against a near-white ground -- the mounted theme's own reason to exist
// (sunlight, a visor) is not touched by this, only extended.
const _mountedInstrumentBlue = Color(0xFF01579B);

const ripprMountedColors = ColorScheme.light(
  primary: _mountedAccent,
  onPrimary: Color(0xFFFFFFFF),
  secondary: Color(0xFF4A4034),
  tertiary: _mountedInstrumentBlue,
  onTertiary: Color(0xFFFFFFFF),
  surface: Color(0xFFFFFFFF),
  onSurface: _mountedInk,
  surfaceContainerHighest: Color(0xFFE7E2D9),
  onSurfaceVariant: _mountedInk,
  outline: Color(0xFF706A5E),
  error: Color(0xFFB3261E),
  onError: Color(0xFFFFFFFF),
);

const ripprMountedBackground = _mountedGround;

/// Scales body/headline text up for legibility at a glance, at speed, behind a visor.
/// Kept separate from V3-16's visual identity work -- this is a stopgap born of a real
/// constraint, not a design pass.
const double mountedTextScale = 1.25;

/// V3-05's mounted mode: high contrast, larger text. Only applied to the record screen
/// while mounted, not the whole app -- everywhere else is still read at a pocket glance.
ThemeData ripprMountedTheme() {
  final base = ThemeData(
    colorScheme: ripprMountedColors,
    useMaterial3: true,
    scaffoldBackgroundColor: _mountedGround,
  );

  return base.copyWith(
    textTheme: base.textTheme.apply(
      bodyColor: _mountedInk,
      displayColor: _mountedInk,
    ),
    appBarTheme: const AppBarTheme(
      backgroundColor: _mountedGround,
      foregroundColor: _mountedInk,
      elevation: 0,
    ),
    dividerTheme: const DividerThemeData(color: Color(0xFFDAD4C8), space: 1),
  );
}

/// WCAG 2.x's contrast ratio: `(L1 + 0.05) / (L2 + 0.05)`, `L1` the lighter of the two
/// relative luminances. AA requires 4.5:1 for normal text, 3:1 for large text (18pt, or
/// 14pt bold) -- see the tests in `theme_test.dart` for V3-16's acceptance criterion,
/// which asserts this directly rather than trusting a palette pick by eye.
double contrastRatio(Color a, Color b) {
  final la = a.computeLuminance();
  final lb = b.computeLuminance();
  final lighter = la > lb ? la : lb;
  final darker = la > lb ? lb : la;
  return (lighter + 0.05) / (darker + 0.05);
}

/// Monospace for anything numeric.
///
/// Digits that change every second must not make the layout jitter, which proportional
/// figures do. Used for every speed, distance and clock in the app.
const TextStyle monoDigits = TextStyle(
  fontFamily: 'monospace',
  fontFeatures: [FontFeature.tabularFigures()],
);