<?php
session_start();
require_once 'db/config.php';
require_once 'auth-check.php';
require_once 'auth-helpers.php';

// Store role name in session if not already set
if (isset($_SESSION['user_role_id']) && !isset($_SESSION['user_role_name'])) {
    try {
        $pdo = db();
        $stmt = $pdo->prepare("SELECT name FROM roles WHERE id = :role_id");
        $stmt->execute([':role_id' => $_SESSION['user_role_id']]);
        $role = $stmt->fetch(PDO::FETCH_ASSOC);
        if ($role) {
            $_SESSION['user_role_name'] = $role['name'];
        }
    } catch (PDOException $e) {
        // Could not fetch role name, do nothing, the check later will handle it
    }
}

// Get allowed fields for the current user
$allowed_fields_str = can($_SESSION['user_role_id'], 'asset', 'read');
$allowed_fields = [];
if ($allowed_fields_str === '*') {
    // Wildcard means all fields
    try {
        $pdo = db();
        $stmt = $pdo->query("SHOW COLUMNS FROM assets");
        $allowed_fields = $stmt->fetchAll(PDO::FETCH_COLUMN);
    } catch (PDOException $e) {
        // Handle error, maybe log it
        $allowed_fields = [];
    }
} elseif ($allowed_fields_str) {
    $allowed_fields = explode(',', $allowed_fields_str);
}

// Function to count total assets
function count_assets($search = '', $status = '') {
    $sql = "SELECT COUNT(*) FROM assets";
    $where = [];
    $params = [];

    // Role-based filtering for 'Employee'
    if (isset($_SESSION['user_role_name']) && strtolower($_SESSION['user_role_name']) === 'employee' && isset($_SESSION['user_id'])) {
        $where[] = "assigned_to = :user_id";
        $params[':user_id'] = $_SESSION['user_id'];
    }

    if (!empty($search)) {
        $where[] = "name LIKE :search";
        $params[':search'] = "%$search%";
    }

    if (!empty($status)) {
        $where[] = "status = :status";
        $params[':status'] = $status;
    }

    if (!empty($where)) {
        $sql .= " WHERE " . implode(' AND ', $where);
    }

    try {
        $pdo = db();
        $stmt = $pdo->prepare($sql);
        $stmt->execute($params);
        return $stmt->fetchColumn();
    } catch (PDOException $e) {
        return 0;
    }
}

// Function to execute query and return results
function get_assets($fields, $search = '', $status = '', $limit = 10, $offset = 0, $sort_by = 'created_at', $sort_order = 'DESC') {
    if (empty($fields)) {
        return []; // No read permission
    }
    // Always include id for edit/delete links
    if (!in_array('id', $fields)) {
        $fields[] = 'id';
    }

    $select_fields = [];
    $join_users = in_array('assigned_to', $fields);

    foreach ($fields as $field) {
        if ($field === 'assigned_to') {
            // Use a different alias for the user name to avoid conflict with the original column name
            $select_fields[] = 'users.name AS assigned_to_name';
        }
        // Always select the original assigned_to field for reference if needed
        $select_fields[] = 'assets.' . $field;
    }
    
    // Remove duplicates that might be caused by adding assets.id and assets.assigned_to
    $select_fields = array_unique($select_fields);

    $select_fields_sql = implode(', ', $select_fields);

    $sql = "SELECT $select_fields_sql FROM assets";

    if ($join_users) {
        $sql .= " LEFT JOIN users ON assets.assigned_to = users.id";
    }

    $where = [];
    $params = [];

    // Role-based filtering for 'Employee'
    if (isset($_SESSION['user_role_name']) && strtolower($_SESSION['user_role_name']) === 'employee' && isset($_SESSION['user_id'])) {
        $where[] = "assets.assigned_to = :user_id";
        $params[':user_id'] = $_SESSION['user_id'];
    }

    if (!empty($search)) {
        // Assuming 'name' is a field that can be searched.
        if (in_array('name', $fields)) {
            $where[] = "assets.name LIKE :search";
            $params[':search'] = "%$search%";
        }
    }

    if (!empty($status)) {
        if (in_array('status', $fields)) {
            $where[] = "assets.status = :status";
            $params[':status'] = $status;
        }
    }

    if (!empty($where)) {
        $sql .= " WHERE " . implode(' AND ', $where);
    }

    // Whitelist sortable columns
    $sortable_columns = array_merge($fields, ['created_at']);
    if ($sort_by === 'assigned_to') {
        $sort_by = 'assigned_to_name'; // Sort by the alias
    } elseif (in_array($sort_by, $fields)) {
        $sort_by = 'assets.' . $sort_by;
    } elseif (!in_array($sort_by, $sortable_columns)) {
        $sort_by = 'assets.created_at';
    }

    $sort_order = strtoupper($sort_order) === 'ASC' ? 'ASC' : 'DESC';

    $sql .= " ORDER BY $sort_by $sort_order LIMIT :limit OFFSET :offset";
    $params[':limit'] = $limit;
    $params[':offset'] = $offset;

    try {
        $pdo = db();
        $stmt = $pdo->prepare($sql);
        // Bind parameters separately to handle integer binding for LIMIT and OFFSET
        foreach ($params as $key => &$val) {
            if ($key === ':limit' || $key === ':offset') {
                $stmt->bindParam($key, $val, PDO::PARAM_INT);
            } else {
                $stmt->bindParam($key, $val);
            }
        }
        $stmt->execute();
        return $stmt->fetchAll(PDO::FETCH_ASSOC);
    } catch (PDOException $e) {
        return ['error' => 'Database error: ' . $e->getMessage()];
    }
}

$search = $_GET['search'] ?? '';
$status = $_GET['status'] ?? '';
$page = isset($_GET['page']) ? (int)$_GET['page'] : 1;
$limit = 10;
$offset = ($page - 1) * $limit;
$sort_by = $_GET['sort_by'] ?? 'created_at';
$sort_order = $_GET['sort_order'] ?? 'DESC';

$total_assets = count_assets($search, $status);
$total_pages = ceil($total_assets / $limit);

$assets = get_assets($allowed_fields, $search, $status, $limit, $offset, $sort_by, $sort_order);

function getStatusClass($status) {
    switch (strtolower($status)) {
        case 'in service':
            return 'status-in-service';
        case 'under repair':
            return 'status-under-repair';
        case 'retired':
            return 'status-retired';
        default:
            return '';
    }
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>IC-Inventory</title>
    <meta name="description" content="Built with Flatlogic Generator">
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css" rel="stylesheet">
    <link rel="stylesheet" href="assets/css/custom.css?v=<?php echo time(); ?>">
    <link rel="preconnect" href="https://fonts.googleapis.com">
    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
    <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap" rel="stylesheet">
    <script src="https://unpkg.com/feather-icons"></script>
</head>
<body>

<div class="wrapper">
    <?php require_once 'templates/sidebar.php'; ?>

    <main id="content">
        <div class="header">
            <h1>Asset Dashboard</h1>
            <div>
                <?php if (can($_SESSION['user_role_id'], 'asset', 'create')): ?>
                    <a href="add-asset.php" class="btn btn-primary">Add New Asset</a>
                <?php endif; ?>
                <div class="theme-switcher" id="theme-switcher">
                    <i data-feather="moon"></i>
                </div>
            </div>
        </div>

        <?php if (isset($_GET['success']) && $_GET['success'] === 'asset_added'): ?>
            <div class="alert alert-success">Asset successfully added!</div>
        <?php elseif (isset($_GET['success']) && $_GET['success'] === 'asset_updated'): ?>
            <div class="alert alert-success">Asset successfully updated!</div>
        <?php elseif (isset($_GET['success']) && $_GET['success'] === 'asset_deleted'): ?>
            <div class="alert alert-success">Asset successfully deleted!</div>
        <?php elseif (isset($_GET['error']) && $_GET['error'] === 'access_denied'): ?>
            <div class="alert alert-danger">You do not have permission to access that page.</div>
        <?php endif; ?>

        <div class="surface p-4">
            <form method="get" class="row g-3 mb-4">
                <div class="col-md-4">
                    <input type="text" name="search" class="form-control" placeholder="Search by asset name..." value="<?php echo htmlspecialchars($search); ?>">
                </div>
                <div class="col-md-3">
                    <select name="status" class="form-select">
                        <option value="">All Statuses</option>
                        <option value="In Service" <?php echo ($status === 'In Service') ? 'selected' : ''; ?>>In Service</option>
                        <option value="Under Repair" <?php echo ($status === 'Under Repair') ? 'selected' : ''; ?>>Under Repair</option>
                        <option value="Retired" <?php echo ($status === 'Retired') ? 'selected' : ''; ?>>Retired</option>
                    </select>
                </div>
                <div class="col-md-2">
                    <button type="submit" class="btn btn-primary">Filter</button>
                </div>
            </form>

            <?php if (isset($assets['error'])): ?>
                <div class="alert alert-danger">
                    <?php echo htmlspecialchars($assets['error']); ?>
                </div>
            <?php elseif (empty($assets)): ?>
                <div class="text-center p-5">
                    <h4>No assets found.</h4>
                    <?php if (can($_SESSION['user_role_id'], 'asset', 'create')): ?>
                        <p>Get started by adding your first company asset.</p>
                        <a href="add-asset.php" class="btn btn-primary">Add Asset</a>
                    <?php endif; ?>
                </div>
            <?php else: ?>
                <div class="table-responsive">
                    <table class="table asset-table">
                        <thead>
                            <tr>
                                <?php
                                $new_sort_order = ($sort_order === 'DESC') ? 'ASC' : 'DESC';
                                foreach ($allowed_fields as $field): if($field === 'id') continue;
                                ?>
                                    <th>
                                        <a href="?page=<?php echo $page; ?>&search=<?php echo urlencode($search); ?>&status=<?php echo urlencode($status); ?>&sort_by=<?php echo $field; ?>&sort_order=<?php echo $new_sort_order; ?>">
                                            <?php echo ucfirst(str_replace('_', ' ', $field)); ?>
                                            <?php if ($sort_by === $field): ?>
                                                <i data-feather="<?php echo ($sort_order === 'DESC') ? 'arrow-down' : 'arrow-up'; ?>"></i>
                                            <?php endif; ?>
                                        </a>
                                    </th>
                                <?php endforeach; ?>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php foreach ($assets as $asset): ?>
                                <tr>
                                    <?php foreach ($allowed_fields as $field): if($field === 'id') continue; ?>
                                        <td>
                                            <?php if ($field === 'status'): ?>
                                                <span class="status <?php echo getStatusClass($asset[$field]); ?>"><?php echo htmlspecialchars($asset[$field]); ?></span>
                                            <?php elseif ($field === 'assigned_to'): ?>
                                                <?php echo htmlspecialchars($asset['assigned_to_name'] ?? ($asset['assigned_to'] ?? '')); ?>
                                            <?php else: ?>
                                                <?php echo htmlspecialchars($asset[$field] ?? ''); ?>
                                            <?php endif; ?>
                                        </td>
                                    <?php endforeach; ?>
                                    <td>
                                        <?php if (can($_SESSION['user_role_id'], 'asset', 'update')): ?>
                                            <a href="edit-asset.php?id=<?php echo $asset['id']; ?>" class="btn btn-sm btn-outline-primary">Edit</a>
                                        <?php endif; ?>
                                        <?php if (can($_SESSION['user_role_id'], 'asset', 'delete')): ?>
                                            <a href="delete-asset.php?id=<?php echo $asset['id']; ?>" class="btn btn-sm btn-outline-danger" onclick="return confirm('Are you sure you want to delete this asset?');">Delete</a>
                                        <?php endif; ?>
                                    </td>
                                </tr>
                            <?php endforeach; ?>
                        </tbody>
                    </table>
                </div>

                <nav aria-label="Page navigation">
                    <ul class="pagination justify-content-center">
                        <?php if ($page > 1): ?>
                            <li class="page-item"><a class="page-link" href="?page=<?php echo $page - 1; ?>&search=<?php echo urlencode($search); ?>&status=<?php echo urlencode($status); ?>&sort_by=<?php echo $sort_by; ?>&sort_order=<?php echo $sort_order; ?>">Previous</a></li>
                        <?php endif; ?>
                        <?php for ($i = 1; $i <= $total_pages; $i++): ?>
                            <li class="page-item <?php echo ($i == $page) ? 'active' : ''; ?>"><a class="page-link" href="?page=<?php echo $i; ?>&search=<?php echo urlencode($search); ?>&status=<?php echo urlencode($status); ?>&sort_by=<?php echo $sort_by; ?>&sort_order=<?php echo $sort_order; ?>"><?php echo $i; ?></a></li>
                        <?php endfor; ?>
                        <?php if ($page < $total_pages): ?>
                            <li class="page-item"><a class="page-link" href="?page=<?php echo $page + 1; ?>&search=<?php echo urlencode($search); ?>&status=<?php echo urlencode($status); ?>&sort_by=<?php echo $sort_by; ?>&sort_order=<?php echo $sort_order; ?>">Next</a></li>
                        <?php endif; ?>
                    </ul>
                </nav>
            <?php endif; ?>
        </div>
    </main>
</div>

<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/js/bootstrap.bundle.min.js"></script>
<script src="assets/js/main.js?v=<?php echo time(); ?>"></script>
<script>
    feather.replace();
</script>
</body>
</html>