<?php
// admin.php - Product Management Panel for Admin Accounts

require_once 'includes/helper.php';
require_once 'classes/Product.php';

start_secure_session();

// Check if user is logged in and is an admin
if (!isset($_SESSION['user_id']) || $_SESSION['role'] !== 'admin') {
    header("Location: index.php");
    exit();
}

$productObj = new Product();
$error = '';
$success = '';
$csrfToken = generate_csrf_token();

$action = $_GET['action'] ?? 'list';
$editProduct = null;

// Handle Product actions (Add, Edit, Delete)
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $token = $_POST['csrf_token'] ?? '';
    if (!validate_csrf_token($token)) {
        $error = "ระบบความปลอดภัย: CSRF Token ไม่ถูกต้อง";
    } else {
        $postAction = $_POST['action'] ?? '';

        if ($postAction === 'create' || $postAction === 'update') {
            $name = trim($_POST['name'] ?? '');
            $description = trim($_POST['description'] ?? '');
            $price = (float)($_POST['price'] ?? 0);
            $stock = (int)($_POST['stock'] ?? 0);
            $size = trim($_POST['size'] ?? 'Free Size');
            $imageUrl = trim($_POST['image_url'] ?? '');

            // Handle file upload
            if (isset($_FILES['product_image']) && $_FILES['product_image']['error'] === UPLOAD_ERR_OK) {
                $fileTmpPath = $_FILES['product_image']['tmp_name'];
                $fileName = $_FILES['product_image']['name'];
                $fileSize = $_FILES['product_image']['size'];
                $fileType = $_FILES['product_image']['type'];
                $fileNameCmps = explode(".", $fileName);
                $fileExtension = strtolower(end($fileNameCmps));

                $allowedExtensions = ['jpg', 'jpeg', 'png', 'gif', 'webp'];
                if (in_array($fileExtension, $allowedExtensions)) {
                    $newFileName = md5(time() . $fileName) . '.' . $fileExtension;
                    $uploadAssetsDir = __DIR__ . '/assets/products/';
                    $uploadThaiDir = __DIR__ . '/รูป/products/';
                    
                    // Create directories if they do not exist
                    if (!is_dir($uploadAssetsDir)) {
                        mkdir($uploadAssetsDir, 0755, true);
                    }
                    if (!is_dir($uploadThaiDir)) {
                        mkdir($uploadThaiDir, 0755, true);
                    }
                    
                    $destAssets = $uploadAssetsDir . $newFileName;
                    $destThai = $uploadThaiDir . $newFileName;
                    
                    if (move_uploaded_file($fileTmpPath, $destAssets)) {
                        @copy($destAssets, $destThai);
                        $imageUrl = 'assets/products/' . $newFileName;
                    } else if (move_uploaded_file($fileTmpPath, $destThai)) {
                        @copy($destThai, $destAssets);
                        $imageUrl = 'assets/products/' . $newFileName;
                    } else {
                        $error = "เกิดข้อผิดพลาดในการบันทึกไฟล์รูปภาพ";
                    }
                } else {
                    $error = "ประเภทไฟล์ไม่ได้รับอนุญาต (อนุญาตเฉพาะ JPG, PNG, GIF, WEBP)";
                }
            }

            if (empty($name)) {
                $error = "กรุณากรอกชื่อสินค้า";
            } else if ($price < 0) {
                $error = "ราคาสินค้าต้องไม่น้อยกว่า 0";
            } else if ($stock < 0) {
                $error = "จำนวนสต็อกสินค้าต้องไม่น้อยกว่า 0";
            } else if (empty($error)) {
                if ($postAction === 'create') {
                    if ($productObj->create($name, $description, $price, $stock, $imageUrl, $size)) {
                        $success = "เพิ่มสินค้าใหม่เรียบร้อยแล้ว!";
                        $action = 'list';
                    } else {
                        $error = "ไม่สามารถบันทึกข้อมูลสินค้าได้";
                    }
                } else if ($postAction === 'update') {
                    $id = (int)$_POST['id'];
                    if ($productObj->update($id, $name, $description, $price, $stock, $imageUrl, $size)) {
                        $success = "แก้ไขข้อมูลสินค้าสำเร็จ!";
                        $action = 'list';
                    } else {
                        $error = "ไม่สามารถแก้ไขข้อมูลสินค้าได้";
                    }
                }
            }
        } else if ($postAction === 'delete') {
            $id = (int)$_POST['id'];
            if ($productObj->delete($id)) {
                $success = "ลบสินค้าสำเร็จ!";
                $action = 'list';
            } else {
                $error = "ไม่สามารถลบสินค้าได้";
            }
        }
    }
}

// Fetch edit product if edit action requested
if ($action === 'edit' && isset($_GET['id'])) {
    $editId = (int)$_GET['id'];
    $editProduct = $productObj->getById($editId);
    if (!$editProduct) {
        $error = "ไม่พบสินค้าที่ต้องการแก้ไข";
        $action = 'list';
    }
}

$products = $productObj->getAll();

require_once 'includes/header.php';
?>

<div class="max-w-7xl mx-auto my-4 sm:my-6 px-4">
    <div class="flex flex-col sm:flex-row items-center justify-between gap-4 mb-8">
        <div>
            <h2 class="text-2xl sm:text-3xl font-extrabold text-white tracking-tight flex items-center gap-3 justify-center sm:justify-start">
                <span>🛠️</span> จัดการสินค้า (Admin Panel)
            </h2>
            <p class="text-slate-400 text-sm mt-1">เพิ่ม ลด แก้ไข และลบสินค้าคงคลังของ CMTC SHOP</p>
        </div>
        <?php if ($action === 'list'): ?>
            <a href="admin.php?action=add" class="px-5 py-2.5 bg-gradient-to-r from-violet-600 to-indigo-600 hover:from-violet-500 hover:to-indigo-500 text-white font-bold rounded-xl shadow-lg transition-all text-sm active:scale-95">
                + เพิ่มสินค้าใหม่
            </a>
        <?php else: ?>
            <a href="admin.php?action=list" class="px-5 py-2.5 bg-slate-900 border border-slate-800 text-slate-300 hover:text-white font-bold rounded-xl transition-all text-sm active:scale-95">
                &larr; กลับรายการสินค้า
            </a>
        <?php endif; ?>
    </div>

    <?php if ($error): ?>
        <div class="bg-red-950/60 border border-red-800 text-red-300 p-4 rounded-2xl text-sm mb-6 animate-pulse">
            ⚠️ <?= escape($error) ?>
        </div>
    <?php endif; ?>

    <?php if ($success): ?>
        <div class="bg-emerald-950/60 border border-emerald-800 text-emerald-300 p-4 rounded-2xl text-sm mb-6">
            🎉 <?= escape($success) ?>
        </div>
    <?php endif; ?>

    <!-- 1. ADD / EDIT PRODUCT FORM -->
    <?php if ($action === 'add' || $action === 'edit'): ?>
        <div class="glass p-6 sm:p-8 rounded-3xl max-w-2xl mx-auto shadow-2xl">
            <h3 class="text-xl font-bold text-white mb-6 border-b border-slate-900 pb-3 flex items-center gap-2">
                <span><?= $action === 'edit' ? '📝 แก้ไขข้อมูลสินค้า' : '✨ เพิ่มสินค้าใหม่' ?></span>
            </h3>
            
            <form action="admin.php?action=<?= $action ?><?= $action === 'edit' ? '&id=' . $editProduct['id'] : '' ?>" method="POST" enctype="multipart/form-data" class="space-y-5">
                <input type="hidden" name="csrf_token" value="<?= escape($csrfToken) ?>">
                <input type="hidden" name="action" value="<?= $action === 'edit' ? 'update' : 'create' ?>">
                <?php if ($action === 'edit'): ?>
                    <input type="hidden" name="id" value="<?= $editProduct['id'] ?>">
                <?php endif; ?>

                <div>
                    <label class="block text-xs font-bold text-slate-400 uppercase tracking-wider mb-2">ชื่อสินค้า <span class="text-red-500">*</span></label>
                    <input type="text" name="name" required value="<?= escape($editProduct['name'] ?? '') ?>"
                           class="w-full px-4 py-2.5 bg-slate-900 border border-slate-800 focus:border-violet-500 rounded-xl focus:ring-1 focus:ring-violet-500 outline-none text-slate-100 placeholder-slate-600 transition-all text-sm" placeholder="ระบุชื่อสินค้า เช่น เสื้อยืดลายพราง">
                </div>

                <div>
                    <label class="block text-xs font-bold text-slate-400 uppercase tracking-wider mb-2">รายละเอียดสินค้า</label>
                    <textarea name="description" rows="4"
                              class="w-full px-4 py-2.5 bg-slate-900 border border-slate-800 focus:border-violet-500 rounded-xl focus:ring-1 focus:ring-violet-500 outline-none text-slate-100 placeholder-slate-600 transition-all text-sm resize-none" placeholder="ระบุคำอธิบายเกี่ยวกับสินค้าคัดเลือก..."><?= escape($editProduct['description'] ?? '') ?></textarea>
                </div>

                <div class="grid grid-cols-1 sm:grid-cols-3 gap-4">
                    <div>
                        <label class="block text-xs font-bold text-slate-400 uppercase tracking-wider mb-2">ราคาจำหน่าย (บาท) <span class="text-red-500">*</span></label>
                        <input type="number" step="0.01" min="0" name="price" required value="<?= escape($editProduct['price'] ?? '0.00') ?>"
                               class="w-full px-4 py-2.5 bg-slate-900 border border-slate-800 focus:border-violet-500 rounded-xl focus:ring-1 focus:ring-violet-500 outline-none text-slate-100 placeholder-slate-600 transition-all text-sm" placeholder="0.00">
                    </div>
                    <div>
                        <label class="block text-xs font-bold text-slate-400 uppercase tracking-wider mb-2">ขนาด (Size)</label>
                        <select name="size"
                                class="w-full px-4 py-2.5 bg-slate-900 border border-slate-800 focus:border-violet-500 rounded-xl focus:ring-1 focus:ring-violet-500 outline-none text-slate-100 transition-all text-sm">
                            <?php 
                            $sizes = ['Free Size', 'XS', 'S', 'M', 'L', 'XL', 'XXL', '38', '39', '40', '41', '42', '43', '44'];
                            $currentSize = $editProduct['size'] ?? 'Free Size';
                            foreach ($sizes as $s): ?>
                                <option value="<?= escape($s) ?>" <?= $currentSize === $s ? 'selected' : '' ?>><?= escape($s) ?></option>
                            <?php endforeach; ?>
                        </select>
                    </div>
                    <div>
                        <label class="block text-xs font-bold text-slate-400 uppercase tracking-wider mb-2">สต็อกคงเหลือ <span class="text-red-500">*</span></label>
                        <input type="number" min="0" name="stock" required value="<?= escape($editProduct['stock'] ?? '0') ?>"
                               class="w-full px-4 py-2.5 bg-slate-900 border border-slate-800 focus:border-violet-500 rounded-xl focus:ring-1 focus:ring-violet-500 outline-none text-slate-100 placeholder-slate-600 transition-all text-sm" placeholder="0">
                    </div>
                </div>

                <div>
                    <label class="block text-xs font-bold text-slate-400 uppercase tracking-wider mb-2">รูปภาพสินค้า</label>
                    
                    <?php if ($action === 'edit' && !empty($editProduct['image_url'])): ?>
                        <?php $editImg = get_product_image_url($editProduct['image_url'] ?? '', $editProduct['name'] ?? ''); ?>
                        <div class="flex items-center gap-3 mb-3 p-3 bg-slate-900/60 rounded-xl border border-slate-800">
                            <img src="<?= escape($editImg) ?>" class="w-12 h-12 object-cover rounded-lg border border-slate-800" onerror="if(!this.dataset.tried){ this.dataset.tried='1'; this.src=(this.src.indexOf('assets/')!==-1 ? this.src.replace('assets/','รูป/') : this.src.replace('รูป/','assets/')); } else { this.style.display='none'; }">
                            <div class="text-xs">
                                <p class="text-slate-300 font-bold">รูปภาพปัจจุบัน</p>
                                <p class="text-slate-500"><?= escape($editProduct['image_url']) ?></p>
                            </div>
                        </div>
                    <?php endif; ?>

                    <div class="space-y-2">
                        <input type="file" name="product_image" accept="image/*"
                               class="block w-full text-xs text-slate-400 file:mr-4 file:py-2 file:px-4 file:rounded-xl file:border-0 file:text-xs file:font-semibold file:bg-violet-600/20 file:text-violet-400 hover:file:bg-violet-600/30 file:cursor-pointer">
                        <p class="text-[10px] text-slate-500">หรือระบุลิงก์/เส้นทางไฟล์รูปภาพด้านล่าง:</p>
                        <input type="text" name="image_url" value="<?= escape($editProduct['image_url'] ?? '') ?>"
                               class="w-full px-4 py-2.5 bg-slate-900 border border-slate-800 focus:border-violet-500 rounded-xl focus:ring-1 focus:ring-violet-500 outline-none text-slate-100 placeholder-slate-600 transition-all text-sm" placeholder="assets/products/filename.png">
                    </div>
                </div>

                <div class="border-t border-slate-900 pt-5 mt-6">
                    <button type="submit" class="w-full py-3.5 bg-gradient-to-r from-violet-600 to-indigo-600 hover:from-violet-500 hover:to-indigo-500 text-white font-bold rounded-xl shadow-lg transition-all text-sm sm:text-base active:scale-95">
                        <?= $action === 'edit' ? 'บันทึกการแก้ไข' : 'บันทึกสินค้าใหม่' ?>
                    </button>
                </div>
            </form>
        </div>

    <!-- 2. PRODUCTS LIST TABLE -->
    <?php else: ?>
        <div class="glass rounded-3xl overflow-hidden shadow-2xl border border-slate-800">
            <div class="overflow-x-auto">
                <table class="w-full text-left border-collapse text-sm">
                    <thead>
                        <tr class="bg-slate-900/60 border-b border-slate-800 text-slate-300 font-bold">
                            <th class="p-4 sm:p-5">สินค้า</th>
                            <th class="p-4 sm:p-5">รายละเอียด</th>
                            <th class="p-4 sm:p-5 text-center">ขนาด</th>
                            <th class="p-4 sm:p-5 text-right">ราคา</th>
                            <th class="p-4 sm:p-5 text-center">สต็อก</th>
                            <th class="p-4 sm:p-5 text-center">การจัดการ</th>
                        </tr>
                    </thead>
                    <tbody class="divide-y divide-slate-900/60 text-slate-200">
                        <?php if (empty($products)): ?>
                            <tr>
                                <td colspan="6" class="p-8 text-center text-slate-500">ยังไม่มีสินค้าในระบบ</td>
                            </tr>
                        <?php else: ?>
                            <?php foreach ($products as $product): ?>
                                <tr class="hover:bg-slate-900/20 transition-colors">
                                    <!-- Product Info & Image -->
                                    <td class="p-4 sm:p-5">
                                        <div class="flex items-center gap-3">
                                            <div class="w-12 h-12 bg-slate-900 border border-slate-800 rounded-lg flex items-center justify-center overflow-hidden flex-shrink-0">
                                                <?php $adminImg = get_product_image_url($product['image_url'] ?? '', $product['name'] ?? ''); ?>
                                                <?php if (!empty($adminImg)): ?>
                                                    <img src="<?= escape($adminImg) ?>" alt="<?= escape($product['name']) ?>" class="w-full h-full object-cover" onerror="if(!this.dataset.tried){ this.dataset.tried='1'; this.src=(this.src.indexOf('assets/')!==-1 ? this.src.replace('assets/','รูป/') : this.src.replace('รูป/','assets/')); } else { this.style.display='none'; if(this.nextElementSibling) this.nextElementSibling.style.display='inline'; }">
                                                    <span class="text-xl hidden">🛍️</span>
                                                <?php else: ?>
                                                    <span class="text-xl">🛍️</span>
                                                <?php endif; ?>
                                            </div>
                                            <div>
                                                <h4 class="font-bold text-slate-100 leading-tight"><?= escape($product['name']) ?></h4>
                                                <span class="text-[10px] text-slate-500">ID: <?= $product['id'] ?></span>
                                            </div>
                                        </div>
                                    </td>
                                    <!-- Description -->
                                    <td class="p-4 sm:p-5 max-w-xs sm:max-w-sm truncate text-slate-400 text-xs">
                                        <?= escape($product['description']) ?>
                                    </td>
                                    <!-- Size -->
                                    <td class="p-4 sm:p-5 text-center whitespace-nowrap">
                                        <span class="px-2.5 py-0.5 rounded-full text-xs font-bold bg-indigo-950/80 text-indigo-400 border border-indigo-800">
                                            <?= escape($product['size'] ?? 'Free Size') ?>
                                        </span>
                                    </td>
                                    <!-- Price -->
                                    <td class="p-4 sm:p-5 text-right font-bold text-violet-400 whitespace-nowrap">
                                        <?= format_price($product['price']) ?>
                                    </td>
                                    <!-- Stock -->
                                    <td class="p-4 sm:p-5 text-center whitespace-nowrap">
                                        <span class="px-2.5 py-0.5 rounded-full text-xs font-bold <?= $product['stock'] > 0 ? 'bg-emerald-950/80 text-emerald-400 border border-emerald-800' : 'bg-red-950/80 text-red-400 border border-red-800' ?>">
                                            <?= $product['stock'] ?> ชิ้น
                                        </span>
                                    </td>
                                    <!-- Actions -->
                                    <td class="p-4 sm:p-5 text-center">
                                        <div class="flex items-center justify-center gap-2">
                                            <!-- Edit Button -->
                                            <a href="admin.php?action=edit&id=<?= $product['id'] ?>" 
                                               class="px-3 py-1.5 bg-slate-900 border border-slate-800 text-slate-300 hover:bg-violet-600 hover:border-violet-500 hover:text-white text-xs font-bold rounded-lg transition-all active:scale-95">
                                                แก้ไข
                                            </a>
                                            <!-- Delete Button -->
                                            <form action="admin.php" method="POST" onsubmit="return confirm('คุณแน่ใจหรือไม่ว่าต้องการลบสินค้านี้?');" class="inline">
                                                <input type="hidden" name="csrf_token" value="<?= escape($csrfToken) ?>">
                                                <input type="hidden" name="action" value="delete">
                                                <input type="hidden" name="id" value="<?= $product['id'] ?>">
                                                <button type="submit" 
                                                        class="px-3 py-1.5 bg-slate-900 border border-slate-800 text-red-400 hover:bg-red-950 hover:border-red-900/60 hover:text-red-300 text-xs font-bold rounded-lg transition-all active:scale-95">
                                                    ลบ
                                                </button>
                                            </form>
                                        </div>
                                    </td>
                                </tr>
                            <?php endforeach; ?>
                        <?php endif; ?>
                    </tbody>
                </table>
            </div>
        </div>
    <?php endif; ?>
</div>

<?php require_once 'includes/footer.php'; ?>