m3e design system enforcement of color scheme generation

design_system_color_scheme.dart

// Copyright 2025 Fredrick Allan Grott. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

import 'package:flex_color_scheme/flex_color_scheme.dart';
import 'package:flutter/material.dart';

/// DesignSystemColorScheme is a way to enforce
/// Material 3 Expressive within the FlexColorScheme generation
/// via the fromSeeds constructor.
///
/// This way multiple apps can be designed with the same basic
/// functions generating the ColorSchemes.
///
/// In this use case I am using 3 brand colors, but the function
/// allows up to 3 brand colors as keys. We want to use the most
/// dominant color as primary and second dominant color as the
/// secondary.
///
/// The FlexSchemeVariant specifies a pre-defined tone set that is
/// used in the ColorScheme generation. The variants that
/// corespond with Material 3 Expressive are:
///   tonalSpot
///   fidelity
///   monochrome
///   neutral
///   vibrant
///   expressive
///   content
///   rainbow
///   fruitSalad
///
///
/// Note that with the highContrast variants for highContrast ColorSchemes
/// one can specify a non highcontrast variant and just move contrast level
/// to a value of 1.0. Or we could use the Monochrom or Neutral for
/// high contrast themes with contgrast level set back to zero.
///
/// @author Fredrick Allan Grott
class DesignSystemColorScheme {
  DesignSystemColorScheme();

  Color primaryKey = const Color(0xfff77f7f);

  Color secondaryKey = const Color(0xffdd7e51);

  Color tertiaryKey = const Color(0xffddcfcf);

  FlexSchemeVariant variantLight = FlexSchemeVariant.vibrant;

  FlexSchemeVariant variantDark = FlexSchemeVariant.vibrant;

  FlexSchemeVariant variantLightHighContrast = FlexSchemeVariant.vibrant;

  FlexSchemeVariant variantDarkHighContrast = FlexSchemeVariant.vibrant;

  double contrastLevelNoContrastTheme = 0.0;

  double contrasLevelHighContrast = 1.0;
}