root
52 lines
1.8 KiB
PHP
52 lines
1.8 KiB
PHP
<?php
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namespace App\Models;
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use InvalidArgumentException;
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/**
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* PHP port of app/Controllers/financial_aid_formula.py
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*/
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class FinancialAidEstimateModel
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{
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private const FEDERAL_POVERTY_BASE = 15960.0;
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private const FEDERAL_POVERTY_STEP = 5680.0;
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private const MASSACHUSETTS_COST_FACTOR = 1.05757;
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private const PROTECTED_INCOME_MULTIPLIER = 2.0;
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private const DISCRETIONARY_CONTRIBUTION_RATE = 0.10;
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public function estimatedAid(float $totalBalance, int $householdSize, float $householdIncome): float
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{
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if ($householdSize < 1) {
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throw new InvalidArgumentException('household_size must be at least 1');
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}
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if ($totalBalance < 0 || $householdIncome < 0) {
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throw new InvalidArgumentException('balance and income cannot be negative');
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}
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$federalPovertyLevel = self::FEDERAL_POVERTY_BASE + (self::FEDERAL_POVERTY_STEP * ($householdSize - 1));
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$adjustedNeedThreshold = $federalPovertyLevel * self::MASSACHUSETTS_COST_FACTOR;
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$protectedIncome = self::PROTECTED_INCOME_MULTIPLIER * $adjustedNeedThreshold;
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$discretionaryIncome = max(0.0, $householdIncome - $protectedIncome);
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$expectedContribution = self::DISCRETIONARY_CONTRIBUTION_RATE * $discretionaryIncome;
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$estimated = $totalBalance - $expectedContribution;
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return round(max(0.0, min($totalBalance, $estimated)), 2);
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}
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public function finalRebate(
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float $totalBalance,
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int $householdSize,
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float $householdIncome,
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float $amountRequested
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): float {
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if ($amountRequested < 0) {
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throw new InvalidArgumentException('amount_requested cannot be negative');
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}
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$estimated = $this->estimatedAid($totalBalance, $householdSize, $householdIncome);
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return min($estimated, $amountRequested, $totalBalance);
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}
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}
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