<?php
/**
 * WebGIS - API Manajemen Data Jalan
 *
 * Endpoint  : /api/jalan.php
 * Tabel     : tb_jalan
 * Geometri  : GeoJSON LineString
 */

// Matikan display_errors agar PHP tidak output HTML error (merusak JSON)
ini_set('display_errors', 0);
ini_set('display_startup_errors', 0);
error_reporting(0);

header('Content-Type: application/json; charset=utf-8');

header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET, POST, PUT, DELETE, OPTIONS');
header('Access-Control-Allow-Headers: Content-Type');

/* Handle preflight request */
if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
    http_response_code(200);
    exit;
}

require_once __DIR__ . '/db.php';

$conn   = getConnection();
$method = $_SERVER['REQUEST_METHOD'];
$id     = isset($_GET['id']) ? (int)$_GET['id'] : null;

try {

    switch ($method) {

        /* ============================================================
           READ — Ambil semua atau satu data jalan
        ============================================================ */
        case 'GET':
            if ($id) {
                /* Satu data */
                $stmt = $conn->prepare(
                    "SELECT id, nama_jalan, status_jalan, panjang_jalan, geojson, created_at
                     FROM tb_jalan WHERE id = ?"
                );
                $stmt->bind_param('i', $id);
                $stmt->execute();
                $result = $stmt->get_result();
                $row    = $result->fetch_assoc();

                if ($row) {
                    $row['geojson'] = json_decode($row['geojson']); // parse ke objek
                    echo json_encode($row);
                } else {
                    http_response_code(404);
                    echo json_encode(['status' => 'gagal', 'pesan' => 'Data jalan tidak ditemukan']);
                }

            } else {
                /* Semua data */
                $filter = isset($_GET['status']) ? $_GET['status'] : null;

                if ($filter) {
                    $stmt = $conn->prepare(
                        "SELECT id, nama_jalan, status_jalan, panjang_jalan, geojson, created_at
                         FROM tb_jalan WHERE status_jalan = ? ORDER BY created_at DESC"
                    );
                    $stmt->bind_param('s', $filter);
                    $stmt->execute();
                    $result = $stmt->get_result();
                } else {
                    $result = $conn->query(
                        "SELECT id, nama_jalan, status_jalan, panjang_jalan, geojson, created_at
                         FROM tb_jalan ORDER BY created_at DESC"
                    );
                }

                $data = [];
                while ($row = $result->fetch_assoc()) {
                    $row['geojson'] = json_decode($row['geojson']);
                    $data[] = $row;
                }
                echo json_encode($data);
            }
            break;

        /* ============================================================
           CREATE — Simpan data jalan baru
           Body (JSON):
             {
               "nama_jalan"    : "Jalan Ahmad Yani",
               "status_jalan"  : "Nasional",   // Nasional|Provinsi|Kabupaten
               "panjang_jalan" : 2345.67,       // meter, dihitung oleh LeafletJS
               "geojson"       : {              // GeoJSON LineString
                 "type": "LineString",
                 "coordinates": [[lng,lat], ...]
               }
             }
        ============================================================ */
        case 'POST':
            $body = json_decode(file_get_contents('php://input'), true);

            if (!$body) {
                http_response_code(400);
                echo json_encode(['status' => 'gagal', 'pesan' => 'Body request tidak valid atau bukan JSON']);
                break;
            }

            $nama_jalan    = trim($body['nama_jalan']    ?? '');
            $status_jalan  = trim($body['status_jalan']  ?? '');
            $panjang_jalan = (float)($body['panjang_jalan'] ?? 0);
            $geojson_raw   = $body['geojson'] ?? null;

            /* Validasi */
            $valid_status = ['Nasional', 'Provinsi', 'Kabupaten'];
            if (!$nama_jalan) {
                http_response_code(400);
                echo json_encode(['status' => 'gagal', 'pesan' => 'nama_jalan tidak boleh kosong']);
                break;
            }
            if (!in_array($status_jalan, $valid_status)) {
                http_response_code(400);
                echo json_encode(['status' => 'gagal', 'pesan' => 'status_jalan tidak valid. Pilih: Nasional, Provinsi, atau Kabupaten']);
                break;
            }
            if (!$geojson_raw || ($geojson_raw['type'] ?? '') !== 'LineString') {
                http_response_code(400);
                echo json_encode(['status' => 'gagal', 'pesan' => 'geojson harus bertipe LineString']);
                break;
            }

            $geojson_str = json_encode($geojson_raw);

            $stmt = $conn->prepare(
                "INSERT INTO tb_jalan (nama_jalan, status_jalan, panjang_jalan, geojson)
                 VALUES (?, ?, ?, ?)"
            );
            $stmt->bind_param('ssds', $nama_jalan, $status_jalan, $panjang_jalan, $geojson_str);

            if ($stmt->execute()) {
                echo json_encode([
                    'status' => 'sukses',
                    'id'     => $conn->insert_id,
                    'pesan'  => 'Data jalan berhasil disimpan'
                ]);
            } else {
                throw new Exception($stmt->error);
            }
            break;

        /* ============================================================
           UPDATE — Perbarui atribut dan/atau koordinat jalan
           Mengirim field yang ingin diubah saja:
           - Edit atribut : { "nama_jalan": "...", "status_jalan": "..." }
           - Geser vertex : { "geojson": {...}, "panjang_jalan": 1234.5 }
           - Keduanya     : { semua field }
        ============================================================ */
        case 'PUT':
            if (!$id) {
                http_response_code(400);
                echo json_encode(['status' => 'gagal', 'pesan' => 'Parameter id diperlukan']);
                break;
            }

            $body = json_decode(file_get_contents('php://input'), true);
            if (!$body) {
                http_response_code(400);
                echo json_encode(['status' => 'gagal', 'pesan' => 'Body tidak valid']);
                break;
            }

            /* Bangun query dinamis berdasarkan field yang dikirim */
            $setClauses = [];
            $paramVals  = [];
            $paramTypes = '';

            if (array_key_exists('nama_jalan', $body)) {
                $v = trim($body['nama_jalan']);
                if (!$v) { http_response_code(400); echo json_encode(['status'=>'gagal','pesan'=>'nama_jalan tidak boleh kosong']); break; }
                $setClauses[] = 'nama_jalan = ?'; $paramVals[] = $v; $paramTypes .= 's';
            }
            if (array_key_exists('status_jalan', $body)) {
                $valid = ['Nasional','Provinsi','Kabupaten'];
                if (!in_array($body['status_jalan'], $valid)) {
                    http_response_code(400); echo json_encode(['status'=>'gagal','pesan'=>'status_jalan tidak valid']); break;
                }
                $setClauses[] = 'status_jalan = ?'; $paramVals[] = $body['status_jalan']; $paramTypes .= 's';
            }
            if (array_key_exists('panjang_jalan', $body)) {
                $setClauses[] = 'panjang_jalan = ?'; $paramVals[] = (float)$body['panjang_jalan']; $paramTypes .= 'd';
            }
            if (array_key_exists('geojson', $body)) {
                $setClauses[] = 'geojson = ?'; $paramVals[] = json_encode($body['geojson']); $paramTypes .= 's';
            }

            if (empty($setClauses)) {
                echo json_encode(['status' => 'gagal', 'pesan' => 'Tidak ada field yang dikirim untuk diupdate']);
                break;
            }

            $paramVals[]  = $id;
            $paramTypes  .= 'i';

            $sql  = 'UPDATE tb_jalan SET ' . implode(', ', $setClauses) . ' WHERE id = ?';
            $stmt = $conn->prepare($sql);
            $stmt->bind_param($paramTypes, ...$paramVals);

            if ($stmt->execute()) {
                echo json_encode(['status' => 'sukses', 'pesan' => 'Data jalan berhasil diperbarui']);
            } else {
                throw new Exception($stmt->error);
            }
            break;

        /* ============================================================
           DELETE — Hapus data jalan
        ============================================================ */
        case 'DELETE':
            if (!$id) {
                http_response_code(400);
                echo json_encode(['status' => 'gagal', 'pesan' => 'Parameter id diperlukan']);
                break;
            }

            $stmt = $conn->prepare("DELETE FROM tb_jalan WHERE id = ?");
            $stmt->bind_param('i', $id);

            if ($stmt->execute() && $stmt->affected_rows > 0) {
                echo json_encode(['status' => 'sukses', 'pesan' => 'Data jalan berhasil dihapus']);
            } else {
                http_response_code(404);
                echo json_encode(['status' => 'gagal', 'pesan' => 'Data tidak ditemukan atau sudah dihapus']);
            }
            break;

        default:
            http_response_code(405);
            echo json_encode(['status' => 'gagal', 'pesan' => 'Method tidak didukung']);
    }

} catch (Exception $e) {
    http_response_code(500);
    echo json_encode(['status' => 'gagal', 'pesan' => 'Server error: ' . $e->getMessage()]);
} finally {
    if ($conn) $conn->close();
}