<?php
require_once __DIR__ . '/../helpers.php';
runAuth();

require_once __DIR__ . '/_grantUtils.php';

global $userId;

$data = readJsonBody();
$grantID = (int) ($data['GrantID'] ?? 0);

if ($grantID <= 0) {
    apiAbort(['OK' => false, 'ERROR' => 'missing_grantid', 'MESSAGE' => 'GrantID is required.']);
}

if ($userId <= 0) {
    apiAbort(['OK' => false, 'ERROR' => 'not_authenticated']);
}

$qGrant = queryOne(
    "SELECT g.*, b.UserID AS OwnerUserID
     FROM ServicePointGrants g
     JOIN Businesses b ON b.ID = g.OwnerBusinessID
     WHERE g.ID = ?
     LIMIT 1",
    [$grantID]
);

if (!$qGrant) {
    apiAbort(['OK' => false, 'ERROR' => 'not_found', 'MESSAGE' => 'Grant not found.']);
}

if ((int) $qGrant['OwnerUserID'] !== $userId) {
    apiAbort(['OK' => false, 'ERROR' => 'not_owner', 'MESSAGE' => 'Only the owner business can update grant terms.']);
}

$statusID = (int) $qGrant['StatusID'];
if ($statusID !== 0 && $statusID !== 1) {
    apiAbort(['OK' => false, 'ERROR' => 'bad_state', 'MESSAGE' => 'Only pending or active grants can be updated.']);
}

$setClauses = [];
$setParams = [];
$previousData = [];
$newData = [];

$validEconomics = ['none', 'flat_fee', 'percent_of_orders'];
$validEligibility = ['public', 'employees', 'guests', 'internal'];
$validTimePolicy = ['always', 'schedule', 'date_range', 'event'];

// Economics
if (isset($data['EconomicsType']) || isset($data['EconomicsValue'])) {
    $eType = trim($data['EconomicsType'] ?? $qGrant['EconomicsType']);
    $eValue = (float) ($data['EconomicsValue'] ?? $qGrant['EconomicsValue']);
    if (!in_array($eType, $validEconomics)) $eType = $qGrant['EconomicsType'];

    if ($eType !== $qGrant['EconomicsType'] || $eValue != (float) $qGrant['EconomicsValue']) {
        $previousData['EconomicsType'] = $qGrant['EconomicsType'];
        $previousData['EconomicsValue'] = (float) $qGrant['EconomicsValue'];
        $newData['EconomicsType'] = $eType;
        $newData['EconomicsValue'] = $eValue;
        $setClauses[] = 'EconomicsType = ?';
        $setParams[] = $eType;
        $setClauses[] = 'EconomicsValue = ?';
        $setParams[] = $eValue;
    }
}

// Eligibility
if (isset($data['EligibilityScope'])) {
    $eScope = trim($data['EligibilityScope']);
    if (!in_array($eScope, $validEligibility)) $eScope = $qGrant['EligibilityScope'];
    if ($eScope !== $qGrant['EligibilityScope']) {
        $previousData['EligibilityScope'] = $qGrant['EligibilityScope'];
        $newData['EligibilityScope'] = $eScope;
        $setClauses[] = 'EligibilityScope = ?';
        $setParams[] = $eScope;
    }
}

// Time policy
if (isset($data['TimePolicyType']) || isset($data['TimePolicyData'])) {
    $tType = trim($data['TimePolicyType'] ?? $qGrant['TimePolicyType']);
    if (!in_array($tType, $validTimePolicy)) $tType = $qGrant['TimePolicyType'];
    $tData = $data['TimePolicyData'] ?? $qGrant['TimePolicyData'];

    $changed = ($tType !== $qGrant['TimePolicyType']);
    if (!$changed && is_array($tData)) {
        $changed = (json_encode($tData) !== ($qGrant['TimePolicyData'] ?? ''));
    }

    if ($changed) {
        $previousData['TimePolicyType'] = $qGrant['TimePolicyType'];
        $previousData['TimePolicyData'] = $qGrant['TimePolicyData'] ?? '';
        $newData['TimePolicyType'] = $tType;
        $newData['TimePolicyData'] = $tData;
        $setClauses[] = 'TimePolicyType = ?';
        $setParams[] = $tType;

        $tDataJson = null;
        if (is_array($tData) && !empty($tData)) {
            $tDataJson = json_encode($tData);
        } elseif (is_string($tData) && trim($tData) !== '') {
            $tDataJson = $tData;
        }
        $setClauses[] = 'TimePolicyData = ?';
        $setParams[] = $tDataJson;
    }
}

if (empty($setClauses)) {
    apiAbort(['OK' => true, 'MESSAGE' => 'No changes detected.', 'GrantID' => $grantID]);
}

$setParams[] = $grantID;
queryTimed(
    "UPDATE ServicePointGrants SET " . implode(', ', $setClauses) . " WHERE ID = ?",
    $setParams
);

// Determine action name for history
$action = 'updated';
if (isset($newData['EconomicsType']) || isset($newData['EconomicsValue'])) $action = 'updated_economics';
if (isset($newData['EligibilityScope'])) $action = 'updated_eligibility';
if (isset($newData['TimePolicyType'])) $action = 'updated_time_policy';

recordGrantHistory(
    $grantID,
    $action,
    $userId,
    (int) $qGrant['OwnerBusinessID'],
    $previousData,
    $newData
);

jsonResponse([
    'OK' => true,
    'GrantID' => $grantID,
    'MESSAGE' => 'Grant updated.',
]);