Files
dobetternorge-tools/includes/FreeTier.php
T
2026-05-23 10:17:34 +02:00

396 lines
14 KiB
PHP

<?php
declare(strict_types=1);
/**
* Credit + tier system for users of tools.dobetternorge.no.
*
* Three tiers: free, plus, pro (NOK pricing, see pricing.php).
*
* Tables:
* user_tool_credits — balance (monthly, resets), bonus_balance (never expires), tier,
* Stripe links, trial_started_at / trial_expires_at / trial_downgraded_at
* user_tool_usage_log — every tool call with credits_used
* user_subscriptions — Stripe subscription ledger
*
* Effective balance = balance + bonus_balance.
* Spend order: deduct from balance first, overflow to bonus_balance.
* Pro tier has the largest monthly allowance (still subject to hourly cap).
*
* Trial is Stripe-driven: when subscription.status='trialing', tier='plus' and
* trial_expires_at mirrors Stripe's trial_end. No homegrown trial cron — the
* Stripe webhook flips tier='free' on subscription.deleted.
*
* CaveauAI client sessions bypass all credit checks.
* Only SSO sessions are subject to limits.
*/
final class FreeTier
{
private const COSTS = [
'corpus-search' => 0,
'search' => 0,
'ask' => 1,
'extract' => 1,
'timeline' => 2,
'redact' => 2,
'barnevernet' => 3,
'advocate' => 3,
'deep-research' => 5,
'transcribe' => 2,
'discrepancy' => 4,
'korrespond' => 3,
];
/** Monthly credit allowance per tier. */
private const MONTHLY_ALLOWANCE = [
'free' => 30,
'plus' => 250,
'pro' => 1000,
];
/** Hourly rate-limit per tier (number of paid tool calls per rolling hour). */
private const HOURLY_CAP = [
'free' => 10,
'plus' => 20,
'pro' => 40,
];
/** Per-user case-storage quota in bytes. */
private const STORAGE_QUOTA = [
'free' => 0,
'plus' => 524288000, // 500 MB
'pro' => 5368709120, // 5 GB
];
/** Credit cost for a given tool slug. Returns 1 for unknown tools. */
public static function cost(string $tool): int
{
return self::COSTS[$tool] ?? 1;
}
public static function monthlyAllowance(string $tier): int
{
return self::MONTHLY_ALLOWANCE[$tier] ?? self::MONTHLY_ALLOWANCE['free'];
}
public static function hourlyCap(string $tier): int
{
return self::HOURLY_CAP[$tier] ?? self::HOURLY_CAP['free'];
}
public static function storageQuota(string $tier): int
{
return self::STORAGE_QUOTA[$tier] ?? 0;
}
/** Fetch a user's tier (defaults to 'free' if no row). */
public static function tier(int $userId): string
{
$row = self::row($userId);
return $row['tier'] ?? 'free';
}
/** Tiers that have access to "My Case" features (upload, save analyses, use case context). */
public static function isPaidTier(string $tier): bool
{
return in_array($tier, ['plus', 'pro'], true);
}
/** True when the user is currently in a Stripe trial (tier='plus', trial_expires_at in future). */
public static function isTrialActive(int $userId): bool
{
$row = self::row($userId);
if (!$row || ($row['tier'] ?? '') !== 'plus') {
return false;
}
$expires = $row['trial_expires_at'] ?? null;
if (!$expires) {
return false;
}
return strtotime((string)$expires) > time();
}
/** Days remaining in the active trial (0 if no trial / expired). */
public static function trialDaysRemaining(int $userId): int
{
if (!self::isTrialActive($userId)) {
return 0;
}
$row = self::row($userId);
$expires = strtotime((string)$row['trial_expires_at']);
return max(0, (int)ceil(($expires - time()) / 86400));
}
/** Fetch the full credits row, applying lazy monthly reset. */
public static function row(int $userId): ?array
{
$db = dbnmDb();
// Auto-refill monthly balance based on tier-specific allowance, only if a new calendar month has begun.
$db->prepare(
"UPDATE user_tool_credits
SET balance = CASE tier
WHEN 'free' THEN " . self::MONTHLY_ALLOWANCE['free'] . "
WHEN 'plus' THEN " . self::MONTHLY_ALLOWANCE['plus'] . "
WHEN 'pro' THEN " . self::MONTHLY_ALLOWANCE['pro'] . "
ELSE balance END,
last_reset = CURDATE()
WHERE user_id = ?
AND (YEAR(last_reset) < YEAR(CURDATE()) OR MONTH(last_reset) < MONTH(CURDATE()))"
)->execute([$userId]);
$stmt = $db->prepare('SELECT * FROM user_tool_credits WHERE user_id = ? LIMIT 1');
$stmt->execute([$userId]);
$row = $stmt->fetch(PDO::FETCH_ASSOC);
return is_array($row) ? $row : null;
}
/**
* Check whether the user may proceed with a tool call.
*
* Returns:
* ['ok' => true, 'balance' => int, 'bonus_balance' => int, 'tier' => string]
* ['ok' => false, 'balance' => int, 'bonus_balance' => int, 'tier' => string,
* 'reason' => 'no_credits'|'rate_limit']
*/
public static function check(int $userId, string $tool): array
{
$db = dbnmDb();
$cost = self::cost($tool);
$row = self::row($userId);
if ($row === null) {
return [
'ok' => false, 'balance' => 0, 'bonus_balance' => 0,
'tier' => 'free', 'reason' => 'no_credits',
];
}
$balance = (int)$row['balance'];
$bonus = (int)$row['bonus_balance'];
$tier = (string)$row['tier'];
$base = [
'balance' => $balance,
'bonus_balance' => $bonus,
'tier' => $tier,
];
// Hourly rate limit (always applies)
$stmt = $db->prepare(
'SELECT COUNT(*) FROM user_tool_usage_log
WHERE user_id = ? AND created_at > DATE_SUB(NOW(), INTERVAL 1 HOUR) AND credits_used > 0'
);
$stmt->execute([$userId]);
$hourly = (int)$stmt->fetchColumn();
if ($hourly >= self::hourlyCap($tier)) {
return $base + ['ok' => false, 'reason' => 'rate_limit'];
}
// Free tool (cost=0) always passes credit check
if ($cost === 0) {
return $base + ['ok' => true];
}
if (($balance + $bonus) < $cost) {
return $base + ['ok' => false, 'reason' => 'no_credits'];
}
return $base + ['ok' => true];
}
/**
* Deduct credits for a completed tool call and log the usage.
* Spends from `balance` first, then `bonus_balance`.
*
* Returns the new effective balance (balance + bonus_balance).
*/
public static function deduct(int $userId, string $tool): int
{
$db = dbnmDb();
$cost = self::cost($tool);
$row = self::row($userId);
if ($cost > 0 && $row !== null) {
$balance = (int)$row['balance'];
$bonus = (int)$row['bonus_balance'];
$fromBalance = min($cost, $balance);
$fromBonus = $cost - $fromBalance;
$db->prepare(
'UPDATE user_tool_credits
SET balance = GREATEST(0, balance - ?),
bonus_balance = GREATEST(0, bonus_balance - ?)
WHERE user_id = ?'
)->execute([$fromBalance, $fromBonus, $userId]);
}
$db->prepare(
'INSERT INTO user_tool_usage_log (user_id, tool, credits_used) VALUES (?, ?, ?)'
)->execute([$userId, $tool, $cost]);
$latest = self::row($userId);
return $latest ? ((int)$latest['balance'] + (int)$latest['bonus_balance']) : 0;
}
/** Effective balance (monthly + bonus). */
public static function balance(int $userId): int
{
$row = self::row($userId);
return $row ? ((int)$row['balance'] + (int)$row['bonus_balance']) : 0;
}
/** Detailed balance breakdown for UI rendering. */
public static function balanceDetail(int $userId): array
{
$row = self::row($userId);
if (!$row) {
return ['balance' => 0, 'bonus_balance' => 0, 'tier' => 'free'];
}
return [
'balance' => (int)$row['balance'],
'bonus_balance' => (int)$row['bonus_balance'],
'tier' => (string)$row['tier'],
'storage_used_bytes' => (int)($row['storage_used_bytes'] ?? 0),
'storage_quota_bytes' => self::storageQuota((string)$row['tier']),
'survey_completed_at' => $row['survey_completed_at'] ?? null,
'subscription_period_end' => $row['subscription_period_end'] ?? null,
'trial_started_at' => $row['trial_started_at'] ?? null,
'trial_expires_at' => $row['trial_expires_at'] ?? null,
'trial_active' => self::isTrialActive($userId),
'trial_days_remaining' => self::trialDaysRemaining($userId),
];
}
/**
* Award one-time bonus credits (survey reward, Stripe topup, manual grant).
* Source is logged via user_tool_usage_log with a negative credits_used value.
*/
public static function awardBonus(int $userId, int $credits, string $source): int
{
if ($credits <= 0) {
return self::balance($userId);
}
$db = dbnmDb();
self::ensureRow($userId);
$db->prepare('UPDATE user_tool_credits SET bonus_balance = bonus_balance + ? WHERE user_id = ?')
->execute([$credits, $userId]);
$db->prepare('INSERT INTO user_tool_usage_log (user_id, tool, credits_used) VALUES (?, ?, ?)')
->execute([$userId, 'bonus:' . substr($source, 0, 40), -$credits]);
return self::balance($userId);
}
/**
* Set or upgrade a user's tier (called by Stripe subscription webhook).
* Refills monthly balance to the new tier's allowance.
*
* When $trialEndIso is non-null, also writes trial_started_at (preserving original on updates)
* and trial_expires_at — used when subscription.status='trialing'.
*/
public static function setTier(
int $userId,
string $tier,
?string $stripeCustomerId,
?string $subscriptionId,
?string $periodEndIso,
?string $trialEndIso = null
): void {
$db = dbnmDb();
self::ensureRow($userId);
$allowance = self::monthlyAllowance($tier);
if ($trialEndIso !== null) {
$db->prepare(
'UPDATE user_tool_credits
SET tier = ?, balance = ?, allowance = ?,
stripe_customer_id = COALESCE(?, stripe_customer_id),
subscription_id = ?,
subscription_period_end = ?,
trial_started_at = COALESCE(trial_started_at, NOW()),
trial_expires_at = ?,
trial_downgraded_at = NULL,
last_reset = CURDATE()
WHERE user_id = ?'
)->execute([$tier, $allowance, $allowance, $stripeCustomerId, $subscriptionId, $periodEndIso, $trialEndIso, $userId]);
} else {
$db->prepare(
'UPDATE user_tool_credits
SET tier = ?, balance = ?, allowance = ?,
stripe_customer_id = COALESCE(?, stripe_customer_id),
subscription_id = ?,
subscription_period_end = ?,
trial_expires_at = NULL,
trial_downgraded_at = NULL,
last_reset = CURDATE()
WHERE user_id = ?'
)->execute([$tier, $allowance, $allowance, $stripeCustomerId, $subscriptionId, $periodEndIso, $userId]);
}
}
/**
* Refill monthly balance at subscription renewal (invoice.paid).
* Does not touch bonus_balance.
*/
public static function refillForRenewal(int $userId, string $tier, ?string $periodEndIso): void
{
$db = dbnmDb();
$allowance = self::monthlyAllowance($tier);
$db->prepare(
'UPDATE user_tool_credits
SET balance = ?,
subscription_period_end = ?,
last_reset = CURDATE()
WHERE user_id = ?'
)->execute([$allowance, $periodEndIso, $userId]);
}
/**
* Revert a user to free tier (subscription canceled, trial ended without conversion).
* Preserves bonus_balance and case_documents (handled by 60-day cron).
* Stamps trial_downgraded_at if a trial was active.
*/
public static function clearTier(int $userId): void
{
$db = dbnmDb();
$db->prepare(
"UPDATE user_tool_credits
SET tier = 'free',
allowance = ?,
balance = ?,
subscription_id = NULL,
subscription_period_end = NULL,
trial_downgraded_at = CASE
WHEN trial_expires_at IS NOT NULL AND trial_downgraded_at IS NULL
THEN NOW()
ELSE trial_downgraded_at
END,
trial_expires_at = NULL
WHERE user_id = ?"
)->execute([self::monthlyAllowance('free'), self::monthlyAllowance('free'), $userId]);
}
/** Mark survey as completed so the bonus can only be claimed once per account. */
public static function markSurveyCompleted(int $userId): void
{
$db = dbnmDb();
self::ensureRow($userId);
$db->prepare('UPDATE user_tool_credits SET survey_completed_at = NOW() WHERE user_id = ?')
->execute([$userId]);
}
public static function hasCompletedSurvey(int $userId): bool
{
$row = self::row($userId);
return !empty($row['survey_completed_at']);
}
/** Create the user_tool_credits row if missing (idempotent). */
public static function ensureRow(int $userId): void
{
$db = dbnmDb();
$db->prepare(
'INSERT IGNORE INTO user_tool_credits (user_id, balance, allowance, tier, last_reset, created_at)
VALUES (?, ?, ?, ?, CURDATE(), NOW())'
)->execute([$userId, self::monthlyAllowance('free'), self::monthlyAllowance('free'), 'free']);
}
}