<?php
declare(strict_types=1);

namespace App\Controllers;

use App\Auth;
use App\Database;

class VehicleController
{
    public const TYPE_LABELS = [
        'own'    => '自有车',
        'rental' => '租车',
    ];

    public function index(): void
    {
        $this->requireLogin();

        $db = Database::get();
        $familyId = Auth::familyId();

        $stmt = $db->prepare('SELECT * FROM vehicles WHERE family_id = ?
            ORDER BY vehicle_type ASC, is_default DESC, id ASC');
        $stmt->execute([$familyId]);
        $vehicles = $stmt->fetchAll();

        // 统计每个车辆被出行方式引用次数
        foreach ($vehicles as &$v) {
            $s = $db->prepare('SELECT COUNT(*) FROM travel_modes WHERE vehicle_id = ?');
            $s->execute([$v['id']]);
            $v['mode_count'] = (int)$s->fetchColumn();
        }
        unset($v);

        view('vehicles/index', [
            'vehicles'  => $vehicles,
            'typeLabels' => self::TYPE_LABELS,
            'pageTitle' => '车辆管理',
        ]);
    }

    public function create(): void
    {
        $this->requireLogin();
        view('vehicles/form', [
            'vehicle'   => null,
            'typeLabels' => self::TYPE_LABELS,
            'pageTitle' => '新增车辆',
        ]);
    }

    public function store(): void
    {
        $this->requireLogin();
        csrf_check();

        $db = Database::get();
        $familyId = Auth::familyId();

        $data = $this->collectInput();
        if ($data['error']) {
            flash('error', $data['error']);
            redirect('vehicles/create');
        }

        // 车牌唯一性
        $chk = $db->prepare('SELECT id FROM vehicles WHERE family_id = ? AND plate_number = ? LIMIT 1');
        $chk->execute([$familyId, $data['plate_number']]);
        if ($chk->fetch()) {
            flash('error', '该车牌号已存在');
            redirect('vehicles/create');
        }

        // 如果是默认自有车，先把其他自有车的 is_default 清掉
        if ($data['vehicle_type'] === 'own' && $data['is_default']) {
            $db->prepare('UPDATE vehicles SET is_default = 0 WHERE family_id = ? AND vehicle_type = "own"')
               ->execute([$familyId]);
        }

        $stmt = $db->prepare('INSERT INTO vehicles
            (family_id, plate_number, model_name, vehicle_type, rental_company, rental_order_no, is_default, notes)
            VALUES (?, ?, ?, ?, ?, ?, ?, ?)');
        $stmt->execute([
            $familyId,
            $data['plate_number'],
            $data['model_name'],
            $data['vehicle_type'],
            $data['rental_company'],
            $data['rental_order_no'],
            $data['is_default'] ? 1 : 0,
            $data['notes'],
        ]);

        flash('error', '创建成功');
        redirect('vehicles/index');
    }

    public function edit(): void
    {
        $this->requireLogin();
        $id = (int)($_GET['id'] ?? 0);
        $db = Database::get();

        $stmt = $db->prepare('SELECT * FROM vehicles WHERE id = ? AND family_id = ?');
        $stmt->execute([$id, Auth::familyId()]);
        $vehicle = $stmt->fetch();
        if (!$vehicle) {
            http_response_code(404);
            exit('车辆不存在');
        }

        view('vehicles/form', [
            'vehicle'   => $vehicle,
            'typeLabels' => self::TYPE_LABELS,
            'pageTitle' => '编辑车辆',
        ]);
    }

    public function update(): void
    {
        $this->requireLogin();
        csrf_check();

        $db = Database::get();
        $familyId = Auth::familyId();
        $id = (int)($_POST['id'] ?? 0);

        $stmt = $db->prepare('SELECT * FROM vehicles WHERE id = ? AND family_id = ?');
        $stmt->execute([$id, $familyId]);
        $old = $stmt->fetch();
        if (!$old) {
            http_response_code(404);
            exit('车辆不存在');
        }

        $data = $this->collectInput();
        if ($data['error']) {
            flash('error', $data['error']);
            redirect('vehicles/edit', ['id' => $id]);
        }

        // 车牌唯一性（排除自身）
        $chk = $db->prepare('SELECT id FROM vehicles WHERE family_id = ? AND plate_number = ? AND id != ? LIMIT 1');
        $chk->execute([$familyId, $data['plate_number'], $id]);
        if ($chk->fetch()) {
            flash('error', '该车牌号已被其他车辆使用');
            redirect('vehicles/edit', ['id' => $id]);
        }

        // 如果改为默认自有车，清掉其他默认
        if ($data['vehicle_type'] === 'own' && $data['is_default']) {
            $db->prepare('UPDATE vehicles SET is_default = 0 WHERE family_id = ? AND vehicle_type = "own" AND id != ?')
               ->execute([$familyId, $id]);
        }

        $stmt = $db->prepare('UPDATE vehicles SET
            plate_number = ?, model_name = ?, vehicle_type = ?,
            rental_company = ?, rental_order_no = ?, is_default = ?, notes = ?
            WHERE id = ?');
        $stmt->execute([
            $data['plate_number'],
            $data['model_name'],
            $data['vehicle_type'],
            $data['rental_company'],
            $data['rental_order_no'],
            $data['is_default'] ? 1 : 0,
            $data['notes'],
            $id,
        ]);

        flash('error', '保存成功');
        redirect('vehicles/index');
    }

    public function destroy(): void
    {
        $this->requireLogin();
        csrf_check();

        $db = Database::get();
        $id = (int)($_POST['id'] ?? 0);

        $stmt = $db->prepare('SELECT * FROM vehicles WHERE id = ? AND family_id = ?');
        $stmt->execute([$id, Auth::familyId()]);
        $vehicle = $stmt->fetch();
        if (!$vehicle) {
            flash('error', '车辆不存在');
            redirect('vehicles/index');
        }

        // 检查是否被出行方式引用
        $cnt = $db->prepare('SELECT COUNT(*) FROM travel_modes WHERE vehicle_id = ?');
        $cnt->execute([$id]);
        $usedCount = (int)$cnt->fetchColumn();
        if ($usedCount > 0) {
            flash('error', "该车辆已被 {$usedCount} 条出行方式引用，无法删除");
            redirect('vehicles/index');
        }

        // 检查是否被节点直接引用（vehicle_id 在 trip_nodes 上也可能存在）
        $cnt2 = $db->prepare('SELECT COUNT(*) FROM trip_nodes WHERE vehicle_id = ?');
        $cnt2->execute([$id]);
        $nodeCount = (int)$cnt2->fetchColumn();
        if ($nodeCount > 0) {
            flash('error', "该车辆已被 {$nodeCount} 个节点使用，无法删除");
            redirect('vehicles/index');
        }

        $stmt = $db->prepare('DELETE FROM vehicles WHERE id = ?');
        $stmt->execute([$id]);

        flash('error', '删除成功');
        redirect('vehicles/index');
    }

    /**
     * 从 $_POST 收集车辆数据并做基本校验
     * @return array {error: string|null, plate_number, model_name, vehicle_type, rental_company, rental_order_no, is_default, notes}
     */
    private function collectInput(): array
    {
        $plateNumber = strtoupper(trim($_POST['plate_number'] ?? ''));
        $modelName   = trim($_POST['model_name'] ?? '');
        $vehicleType = $_POST['vehicle_type'] ?? 'own';
        $rentalCompany = trim($_POST['rental_company'] ?? '');
        $rentalOrderNo = trim($_POST['rental_order_no'] ?? '');
        $isDefault   = !empty($_POST['is_default']);
        $notes       = trim($_POST['notes'] ?? '');

        if ($plateNumber === '') {
            return ['error' => '车牌号不能为空'];
        }
        if (mb_strlen($plateNumber) > 20) {
            return ['error' => '车牌号不能超过 20 个字符'];
        }
        if ($modelName === '') {
            return ['error' => '车型名称不能为空'];
        }
        if (!in_array($vehicleType, ['own', 'rental'], true)) {
            return ['error' => '无效的车辆类型'];
        }
        // 自有车不能是默认租车
        if ($vehicleType === 'rental') {
            $isDefault = false;
        }

        return [
            'error'            => null,
            'plate_number'     => $plateNumber,
            'model_name'       => $modelName,
            'vehicle_type'     => $vehicleType,
            'rental_company'   => $vehicleType === 'rental' ? ($rentalCompany ?: null) : null,
            'rental_order_no'  => $vehicleType === 'rental' ? ($rentalOrderNo ?: null) : null,
            'is_default'       => $isDefault,
            'notes'            => $notes ?: null,
        ];
    }

    private function requireLogin(): void
    {
        if (!Auth::check()) {
            redirect('auth/login');
        }
    }
}