/// Post-log feedback card for the log screen: what was just logged, plus
/// today's standing against the daily budget.
library;

import 'package:diet_guard_app/ui/theme.dart';
import 'package:flutter/material.dart';

/// Everything [TodayProgressCard] renders, computed by the caller.
///
/// A plain value object rather than a service lookup so the card stays a
/// pure function of its inputs -- the log screen already holds the freshly
/// written log when it builds one of these, so a second read would be both
/// redundant and a chance to race.
@immutable
class TodayProgress {
  /// Creates a [TodayProgress].
  const TodayProgress({
    required this.consumedKcal,
    required this.budgetKcal,
    required this.proteinG,
    required this.carbsG,
    required this.fatG,
    required this.adherenceStreak,
  });

  /// Today's total calories, including the meal just logged.
  final double consumedKcal;

  /// The budget in effect *today* (not the schedule -- the card is only ever
  /// about the current day).
  final int budgetKcal;

  /// Today's total protein, grams.
  final double proteinG;

  /// Today's total carbohydrate, grams.
  final double carbsG;

  /// Today's total fat, grams.
  final double fatG;

  /// Consecutive-day budget-adherence streak, as of today.
  final int adherenceStreak;

  /// Calories still available today; negative once over budget.
  double get remainingKcal => budgetKcal - consumedKcal;

  /// Whether today's total has passed the budget.
  bool get isOverBudget => remainingKcal < 0;
}

/// Shows today's running budget position after a meal is logged.
///
/// It used to open with a `Logged "<meal>".` line, removed 2026-08-16: the
/// user had just typed that description, so it restated the input instead of
/// telling them anything. What remains is what they act on.
///
/// Replaces the old one-tap-reward prompt: the same slot in the log screen,
/// but showing information the user actually acts on instead of an
/// externally-configured URL. Deliberately has no protein *target* -- that
/// derives from body weight, which only the PC stores (see
/// `diet_guard/_budget.py`'s `protein_target_g`), so the card reports
/// protein consumed and leaves targets to the gate's dashboard.
class TodayProgressCard extends StatelessWidget {
  /// Creates a [TodayProgressCard].
  const TodayProgressCard({required this.progress, super.key});

  /// The values to display.
  final TodayProgress progress;

  static String _plural(int count) => count == 1 ? 'day' : 'days';

  static String _grams(double value) => '${value.round()}g';

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colors = theme.colorScheme;
    final remaining = progress.remainingKcal.abs().round();
    final remainingLabel = progress.isOverBudget
        ? '$remaining over'
        : '$remaining left';
    return Container(
      width: double.infinity,
      padding: const EdgeInsets.all(AppSpacing.md),
      decoration: BoxDecoration(
        // Fill-only elevation: the shared design system forbids shadows in
        // dark UI, and mixing a border with a fill on the same surface.
        color: colors.surfaceContainerHigh,
        borderRadius: BorderRadius.circular(AppRadius.md),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            crossAxisAlignment: CrossAxisAlignment.baseline,
            textBaseline: TextBaseline.alphabetic,
            children: [
              Text(
                '${progress.consumedKcal.round()} / ${progress.budgetKcal}',
                style: theme.textTheme.titleMedium?.copyWith(
                  color: progress.isOverBudget
                      ? colors.error
                      : colors.onSurface,
                ),
              ),
              const SizedBox(width: AppSpacing.xs),
              Text('kcal', style: theme.textTheme.labelSmall),
              const Spacer(),
              Text(
                remainingLabel,
                style: theme.textTheme.labelMedium?.copyWith(
                  color: progress.isOverBudget
                      ? colors.error
                      : colors.onSurfaceVariant,
                ),
              ),
            ],
          ),
          const SizedBox(height: AppSpacing.xs),
          Text(
            'P ${_grams(progress.proteinG)}  ·  '
            'C ${_grams(progress.carbsG)}  ·  '
            'F ${_grams(progress.fatG)}',
            style: theme.textTheme.labelSmall,
          ),
          const SizedBox(height: AppSpacing.xs),
          Text(
            'Adherence streak: ${progress.adherenceStreak} '
            '${_plural(progress.adherenceStreak)}',
            style: theme.textTheme.labelSmall,
          ),
        ],
      ),
    );
  }
}