Files
fuel-price/app/Services/Prediction/Signals/DayOfWeekSignal.php
Ovidiu U 7f64c42a23 refactor: extract DbDialect helper, inline ProfileValidationRules trait
Audit items #17 and #21.

#17 — DayOfWeekSignal and StickinessSignal each had their own
isSqlite ternary picking between SQLite (strftime/julianday) and
MySQL (DAYOFWEEK/DATEDIFF) date expressions. Centralised in
App\Services\Prediction\Signals\DbDialect.

#21 — ProfileValidationRules was a trait with one consumer
(CreateNewUser); inlined the rules into the action and deleted the
trait. Also dropped PasswordValidationRules::currentPasswordRules()
which was unused. PasswordValidationRules trait stays (two consumers).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-29 20:00:01 +01:00

81 lines
3.0 KiB
PHP

<?php
namespace App\Services\Prediction\Signals;
use Illuminate\Support\Facades\DB;
final class DayOfWeekSignal extends AbstractSignal
{
private const int MIN_DAYS = 21;
public function compute(SignalContext $context): array
{
$dowExpr = DbDialect::dayOfWeekExpr('price_effective_at');
$rows = DB::table('station_prices')
->where('fuel_type', $context->fuelType->value)
->where('price_effective_at', '>=', now()->subDays(90))
->selectRaw("{$dowExpr} as dow, DATE(price_effective_at) as day, AVG(price_pence) as avg_price")
->groupBy('dow', 'day')
->get();
$uniqueDays = $rows->pluck('day')->unique()->count();
if ($uniqueDays < self::MIN_DAYS) {
return $this->disabledSignal("Insufficient history for day-of-week pattern ({$uniqueDays} days, need ".self::MIN_DAYS.')');
}
$dowAverages = $rows->groupBy('dow')->map(fn ($g) => $g->avg('avg_price'));
$weekAvg = $dowAverages->avg();
$todayDow = (int) now()->format('w') + 1; // PHP 0=Sun → MySQL 1=Sun
$todayAvg = $dowAverages->get($todayDow, $weekAvg);
$cheapestDow = $dowAverages->keys()->sortBy(fn ($k) => $dowAverages[$k])->first();
$dayNames = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'];
$todayName = $dayNames[($todayDow - 1) % 7] ?? 'Today';
$tomorrowName = $dayNames[$todayDow % 7] ?? 'Tomorrow';
$todayDeltaPence = round(($todayAvg - $weekAvg) / 100, 1);
$tomorrowDeltaPence = round(($dowAverages->get(($todayDow % 7) + 1, $weekAvg) - $todayAvg) / 100, 1);
$direction = match (true) {
($todayAvg - $weekAvg) / 100 >= 1.5 => 'up',
($weekAvg - $todayAvg) / 100 >= 1.5 => 'down',
default => 'stable',
};
$score = $direction === 'stable' ? 0.0 : ($direction === 'up' ? 1.0 : -1.0);
$parts = [];
$parts[] = abs($todayDeltaPence) < 0.1
? "Today ({$todayName}) is typically in line with the weekly average."
: sprintf(
'Today (%s) is typically %sp %s the weekly average.',
$todayName,
number_format(abs($todayDeltaPence), 1),
$todayDeltaPence > 0 ? 'above' : 'below',
);
$parts[] = abs($tomorrowDeltaPence) < 0.1
? "Tomorrow ({$tomorrowName}) is typically the same."
: sprintf(
'Tomorrow (%s) is typically %sp %s.',
$tomorrowName,
number_format(abs($tomorrowDeltaPence), 1),
$tomorrowDeltaPence < 0 ? 'cheaper' : 'pricier',
);
if ($cheapestDow === $todayDow) {
$parts[] = 'Today is historically the cheapest day of the week.';
}
return [
'score' => $score,
'confidence' => min(1.0, $uniqueDays / 90),
'direction' => $direction,
'detail' => implode(' ', $parts),
'data_points' => $uniqueDays,
'enabled' => true,
];
}
}