<?php
header('Content-Type: application/json');
require_once 'config.php';

function randomFloat($min, $max) {
    return $min + (mt_rand() / mt_getrandmax()) * ($max - $min);
}

function buildGridLocation($bbox, $index, $total) {
    $rows = max(1, (int)ceil(sqrt($total)));
    $cols = max(1, (int)ceil($total / $rows));

    $row = intdiv($index, $cols);
    $col = $index % $cols;

    $latStep = ($bbox['max_lat'] - $bbox['min_lat']) / $rows;
    $lngStep = ($bbox['max_lng'] - $bbox['min_lng']) / $cols;

    $baseLat = $bbox['min_lat'] + ($row + 0.5) * $latStep;
    $baseLng = $bbox['min_lng'] + ($col + 0.5) * $lngStep;

    $latMin = max($bbox['min_lat'], $baseLat - $latStep * 0.35);
    $latMax = min($bbox['max_lat'], $baseLat + $latStep * 0.35);
    $lngMin = max($bbox['min_lng'], $baseLng - $lngStep * 0.35);
    $lngMax = min($bbox['max_lng'], $baseLng + $lngStep * 0.35);

    return [
        'latitude' => randomFloat($latMin, $latMax),
        'longitude' => randomFloat($lngMin, $lngMax)
    ];
}

function distanceSquared($lat1, $lng1, $lat2, $lng2) {
    $dLat = $lat1 - $lat2;
    $dLng = $lng1 - $lng2;
    return ($dLat * $dLat) + ($dLng * $dLng);
}

function findNearestMasjidId($latitude, $longitude, $masjids) {
    $nearestId = null;
    $nearestDistance = null;

    foreach ($masjids as $masjid) {
        $distance = distanceSquared($latitude, $longitude, $masjid['latitude'], $masjid['longitude']);
        if ($nearestDistance === null || $distance < $nearestDistance) {
            $nearestDistance = $distance;
            $nearestId = $masjid['id'];
        }
    }

    return $nearestId;
}

try {
    $db = getDB();
    $force = isset($_POST['force']) || isset($_GET['force']);

    // Load GeoJSON land polygons to avoid placing points at sea
    $geojsonPath = __DIR__ . '/../export.geojson';
    $landPolygons = [];
    if (file_exists($geojsonPath)) {
        $gj = json_decode(file_get_contents($geojsonPath), true);
        if ($gj && isset($gj['features']) && is_array($gj['features'])) {
            foreach ($gj['features'] as $feature) {
                if (!isset($feature['geometry'])) continue;
                $geom = $feature['geometry'];
                if ($geom['type'] === 'Polygon') {
                    $landPolygons[] = $geom['coordinates'];
                } elseif ($geom['type'] === 'MultiPolygon') {
                    foreach ($geom['coordinates'] as $poly) $landPolygons[] = $poly;
                }
            }
        }
    }

    function pointInRing($lat, $lng, $ring) {
        $inside = false;
        $j = count($ring) - 1;
        for ($i = 0; $i < count($ring); $i++) {
            $xi = $ring[$i][0]; $yi = $ring[$i][1];
            $xj = $ring[$j][0]; $yj = $ring[$j][1];
            $intersect = (($yi > $lat) != ($yj > $lat)) && ($lng < ($xj - $xi) * ($lat - $yi) / ($yj - $yi + 0.0) + $xi);
            if ($intersect) $inside = !$inside;
            $j = $i;
        }
        return $inside;
    }

    function isPointOnLand($lat, $lng, $landPolygons) {
        if (empty($landPolygons)) return true; // if no polygons available, default to true
        foreach ($landPolygons as $poly) {
            // poly is array of rings; test outer ring first
            $outer = $poly[0];
            if (pointInRing($lat, $lng, $outer)) {
                // ensure not in hole
                $isInHole = false;
                for ($r = 1; $r < count($poly); $r++) {
                    if (pointInRing($lat, $lng, $poly[$r])) {
                        $isInHole = true;
                        break;
                    }
                }
                if (!$isInHole) return true;
            }
        }
        return false;
    }

    $regional_data = [
        ['region' => 'Jakarta', 'province' => 'DKI Jakarta', 'bbox' => ['min_lat' => -6.40, 'max_lat' => -5.90, 'min_lng' => 106.60, 'max_lng' => 106.95], 'masjids' => 15, 'need_points' => 2435],
        ['region' => 'Bandung', 'province' => 'Jawa Barat', 'bbox' => ['min_lat' => -7.50, 'max_lat' => -5.90, 'min_lng' => 106.00, 'max_lng' => 108.10], 'masjids' => 10, 'need_points' => 1500],
        ['region' => 'Bekasi', 'province' => 'Jawa Barat', 'bbox' => ['min_lat' => -7.20, 'max_lat' => -6.00, 'min_lng' => 106.50, 'max_lng' => 108.00], 'masjids' => 6, 'need_points' => 800],
        ['region' => 'Semarang', 'province' => 'Jawa Tengah', 'bbox' => ['min_lat' => -8.10, 'max_lat' => -5.90, 'min_lng' => 108.30, 'max_lng' => 111.20], 'masjids' => 9, 'need_points' => 1400],
        ['region' => 'Yogyakarta', 'province' => 'DI Yogyakarta', 'bbox' => ['min_lat' => -8.20, 'max_lat' => -7.30, 'min_lng' => 109.90, 'max_lng' => 110.90], 'masjids' => 7, 'need_points' => 900],
        ['region' => 'Surabaya', 'province' => 'Jawa Timur', 'bbox' => ['min_lat' => -8.80, 'max_lat' => -6.80, 'min_lng' => 111.00, 'max_lng' => 114.50], 'masjids' => 12, 'need_points' => 1800],
        ['region' => 'Malang', 'province' => 'Jawa Timur', 'bbox' => ['min_lat' => -8.60, 'max_lat' => -7.30, 'min_lng' => 110.80, 'max_lng' => 113.20], 'masjids' => 5, 'need_points' => 700],
        ['region' => 'Medan', 'province' => 'Sumatera Utara', 'bbox' => ['min_lat' => 1.00, 'max_lat' => 4.50, 'min_lng' => 98.00, 'max_lng' => 100.50], 'masjids' => 11, 'need_points' => 1600],
        ['region' => 'Palembang', 'province' => 'Sumatera Selatan', 'bbox' => ['min_lat' => -4.20, 'max_lat' => -2.00, 'min_lng' => 103.00, 'max_lng' => 106.10], 'masjids' => 8, 'need_points' => 1100],
        ['region' => 'Pekanbaru', 'province' => 'Riau', 'bbox' => ['min_lat' => -0.60, 'max_lat' => 2.20, 'min_lng' => 100.00, 'max_lng' => 102.90], 'masjids' => 6, 'need_points' => 850],
        ['region' => 'Jambi', 'province' => 'Jambi', 'bbox' => ['min_lat' => -2.30, 'max_lat' => 0.50, 'min_lng' => 101.00, 'max_lng' => 104.20], 'masjids' => 4, 'need_points' => 600],
        ['region' => 'Padang', 'province' => 'Sumatera Barat', 'bbox' => ['min_lat' => -2.90, 'max_lat' => 1.00, 'min_lng' => 99.40, 'max_lng' => 101.80], 'masjids' => 5, 'need_points' => 700],
        ['region' => 'Makassar', 'province' => 'Sulawesi Selatan', 'bbox' => ['min_lat' => -6.50, 'max_lat' => -2.50, 'min_lng' => 118.00, 'max_lng' => 121.80], 'masjids' => 9, 'need_points' => 1300],
        ['region' => 'Manado', 'province' => 'Sulawesi Utara', 'bbox' => ['min_lat' => 0.80, 'max_lat' => 4.00, 'min_lng' => 123.00, 'max_lng' => 125.80], 'masjids' => 4, 'need_points' => 550],
        ['region' => 'Kendari', 'province' => 'Sulawesi Tenggara', 'bbox' => ['min_lat' => -6.50, 'max_lat' => -2.00, 'min_lng' => 120.00, 'max_lng' => 124.50], 'masjids' => 3, 'need_points' => 400],
        ['region' => 'Palu', 'province' => 'Sulawesi Tengah', 'bbox' => ['min_lat' => -3.00, 'max_lat' => 2.00, 'min_lng' => 118.00, 'max_lng' => 123.50], 'masjids' => 4, 'need_points' => 500],
        ['region' => 'Banjarmasin', 'province' => 'Kalimantan Selatan', 'bbox' => ['min_lat' => -4.20, 'max_lat' => -1.00, 'min_lng' => 114.00, 'max_lng' => 116.80], 'masjids' => 7, 'need_points' => 1000],
        ['region' => 'Pontianak', 'province' => 'Kalimantan Barat', 'bbox' => ['min_lat' => -3.50, 'max_lat' => 3.00, 'min_lng' => 108.00, 'max_lng' => 112.80], 'masjids' => 5, 'need_points' => 700],
        ['region' => 'Samarinda', 'province' => 'Kalimantan Timur', 'bbox' => ['min_lat' => -2.80, 'max_lat' => 2.00, 'min_lng' => 115.00, 'max_lng' => 119.80], 'masjids' => 6, 'need_points' => 850],
        ['region' => 'Palangkaraya', 'province' => 'Kalimantan Tengah', 'bbox' => ['min_lat' => -3.80, 'max_lat' => 1.20, 'min_lng' => 112.00, 'max_lng' => 116.50], 'masjids' => 3, 'need_points' => 450],
        ['region' => 'Jayapura', 'province' => 'Papua', 'bbox' => ['min_lat' => -9.50, 'max_lat' => -1.00, 'min_lng' => 130.00, 'max_lng' => 141.50], 'masjids' => 4, 'need_points' => 700],
        ['region' => 'Mataram', 'province' => 'Nusa Tenggara Barat', 'bbox' => ['min_lat' => -9.20, 'max_lat' => -7.00, 'min_lng' => 115.20, 'max_lng' => 119.00], 'masjids' => 3, 'need_points' => 450],
        ['region' => 'Kupang', 'province' => 'Nusa Tenggara Timur', 'bbox' => ['min_lat' => -11.20, 'max_lat' => -8.00, 'min_lng' => 118.50, 'max_lng' => 125.50], 'masjids' => 2, 'need_points' => 300],
        ['region' => 'Ambon', 'province' => 'Maluku', 'bbox' => ['min_lat' => -8.50, 'max_lat' => -1.00, 'min_lng' => 125.00, 'max_lng' => 134.50], 'masjids' => 2, 'need_points' => 250],
        ['region' => 'Denpasar', 'province' => 'Bali', 'bbox' => ['min_lat' => -9.20, 'max_lat' => -8.00, 'min_lng' => 114.50, 'max_lng' => 115.80], 'masjids' => 1, 'need_points' => 100]
    ];

    $stmt = $db->prepare('SELECT COUNT(*) as count FROM masjids');
    $stmt->execute();
    $masjidCount = (int)$stmt->fetch(PDO::FETCH_ASSOC)['count'];

    if ($masjidCount > 20 && !$force) {
        http_response_code(200);
        echo json_encode([
            'success' => true,
            'message' => 'Regional poverty data already exists. Use force=true to reseed.',
            'current_masjid_count' => $masjidCount
        ]);
        exit;
    }

    if ($force && $masjidCount > 0) {
        $db->exec('DELETE FROM need_points');
        $db->exec('DELETE FROM masjids');
    }

    $db->beginTransaction();

    $masjidStmt = $db->prepare('INSERT INTO masjids (name, latitude, longitude, radius_meters) VALUES (?, ?, ?, ?)');
    $needPointStmt = $db->prepare('INSERT INTO need_points (name, latitude, longitude, masjid_id, household_name, head_name, economic_status) VALUES (?, ?, ?, ?, ?, ?, ?)');

    $insertedMasjids = 0;
    $insertedNeedPoints = 0;

    foreach ($regional_data as $region) {
        $provinceMasjids = [];

        for ($i = 0; $i < $region['masjids']; $i++) {
            // ensure masjid sits on land (try a few attempts)
            $attempt = 0;
            do {
                $location = buildGridLocation($region['bbox'], $i, $region['masjids']);
                $attempt++;
            } while ($attempt < 8 && !isPointOnLand($location['latitude'], $location['longitude'], $landPolygons));
            $latSpan = $region['bbox']['max_lat'] - $region['bbox']['min_lat'];
            $lngSpan = $region['bbox']['max_lng'] - $region['bbox']['min_lng'];
            $coverageEstimate = (int)round((($latSpan + $lngSpan) * 111000) / max(1, $region['masjids']) * 0.55);
            $radiusMeters = max(20000, min(180000, $coverageEstimate + rand(3000, 12000)));

            $masjidStmt->execute([
                'Masjid ' . $region['region'] . ' - ' . ($i + 1),
                $location['latitude'],
                $location['longitude'],
                $radiusMeters
            ]);

            $provinceMasjids[] = [
                'id' => (int)$db->lastInsertId(),
                'latitude' => $location['latitude'],
                'longitude' => $location['longitude']
            ];

            $insertedMasjids++;
        }

        for ($i = 0; $i < $region['need_points']; $i++) {
            // ensure need point lands on land; allow several tries
            $attempt = 0;
            do {
                $pointLocation = buildGridLocation($region['bbox'], $i, $region['need_points']);
                $attempt++;
            } while ($attempt < 12 && !isPointOnLand($pointLocation['latitude'], $pointLocation['longitude'], $landPolygons));
            $nearestMasjidId = findNearestMasjidId($pointLocation['latitude'], $pointLocation['longitude'], $provinceMasjids);

            // generate household and head names and economic status
            $hhName = 'Keluarga ' . $region['region'] . ' - ' . ($i + 1);
            $firstNames = ['Ahmad','Budi','Siti','Aulia','Rizal','Dewi','Agus','Fitri','Hendra','Yulia'];
            $lastNames = ['Santoso','Wijaya','Pratama','Hidayat','Saputra','Nur','Ibrahim','Setiawan','Rahman','Putri'];
            $headName = $firstNames[array_rand($firstNames)] . ' ' . $lastNames[array_rand($lastNames)];
            $statuses = ['sangat_miskin','miskin','rentan','cukup','baik'];
            $econ = $statuses[array_rand($statuses)];

            $needPointStmt->execute([
                'Keluarga Miskin ' . $region['region'] . ' - ' . ($i + 1),
                $pointLocation['latitude'],
                $pointLocation['longitude'],
                $nearestMasjidId,
                $hhName,
                $headName,
                $econ
            ]);

            $insertedNeedPoints++;
        }
    }

    $db->commit();

    http_response_code(200);
    echo json_encode([
        'success' => true,
        'message' => 'Regional poverty assistance data seeded successfully',
        'masjids_inserted' => $insertedMasjids,
        'need_points_inserted' => $insertedNeedPoints,
        'regions_covered' => count($regional_data),
        'total_need_points_capacity' => 21935
    ]);
} catch (PDOException $e) {
    if (isset($db) && $db->inTransaction()) {
        $db->rollBack();
    }
    http_response_code(500);
    echo json_encode([
        'success' => false,
        'error' => 'Database error: ' . $e->getMessage()
    ]);
} catch (Exception $e) {
    if (isset($db) && $db->inTransaction()) {
        $db->rollBack();
    }
    http_response_code(400);
    echo json_encode([
        'success' => false,
        'error' => $e->getMessage()
    ]);
}
?>