<?php
declare(strict_types=1);

require_once __DIR__ . '/../inc/auth.php';
require_once __DIR__ . '/../inc/users.php';

require_auth();
$user = get_logged_in_user();

const MIN_PASSWORD_LENGTH = 8;

// Role is a label only right now — every account has identical access
// regardless of what's stored here. This just keeps the value to a known,
// displayable set instead of trusting arbitrary POST input.
const ALLOWED_ROLES = ['admin', 'manager', 'staff'];
const DEFAULT_ROLE = 'admin';

/**
 * Safely read a trimmed string from a POST payload, guarding against
 * unexpected non-string input (e.g. a spoofed `name[]=` array field).
 */
function post_str(array $data, string $key, string $default = ''): string {
    $value = $data[$key] ?? $default;
    return is_string($value) ? trim($value) : $default;
}

function post_role(array $data): string {
    $role = post_str($data, 'role', DEFAULT_ROLE);
    return in_array($role, ALLOWED_ROLES, true) ? $role : DEFAULT_ROLE;
}

function validate_username(string $username): ?string {
    if ($username === '') {
        return 'Username is required.';
    }
    if (strlen($username) < 3 || strlen($username) > 32) {
        return 'Username must be between 3 and 32 characters.';
    }
    if (!preg_match('/^[a-zA-Z0-9_.-]+$/', $username)) {
        return 'Username can only contain letters, numbers, and . _ -';
    }
    return null;
}

function handle_create_user(array $post, array $currentUser): array {
    $username = post_str($post, 'username');
    $password = post_str($post, 'password');
    $confirm = post_str($post, 'confirm_password');

    if ($error = validate_username($username)) {
        return ['success' => false, 'error' => $error];
    }
    if (username_exists($username)) {
        return ['success' => false, 'error' => 'That username is already taken.'];
    }
    if (strlen($password) < MIN_PASSWORD_LENGTH) {
        return ['success' => false, 'error' => 'Password must be at least ' . MIN_PASSWORD_LENGTH . ' characters.'];
    }
    if ($password !== $confirm) {
        return ['success' => false, 'error' => 'Passwords do not match.'];
    }

    $newId = create_user($username, $password, post_role($post));
    return ['success' => true, 'user' => get_user_by_id($newId)];
}

function handle_change_password(array $post, array $currentUser): array {
    $targetId = (int) ($post['user_id'] ?? 0);
    $target = $targetId > 0 ? get_user_by_id($targetId) : null;
    if (!$target) {
        return ['success' => false, 'error' => 'User not found.'];
    }

    $newPassword = post_str($post, 'new_password');
    $confirm = post_str($post, 'confirm_password');
    $isSelf = $targetId === (int) $currentUser['id'];

    if ($isSelf) {
        $currentPassword = post_str($post, 'current_password');
        if (!verify_user_password($targetId, $currentPassword)) {
            return ['success' => false, 'error' => 'Your current password is incorrect.'];
        }
    }

    if (strlen($newPassword) < MIN_PASSWORD_LENGTH) {
        return ['success' => false, 'error' => 'Password must be at least ' . MIN_PASSWORD_LENGTH . ' characters.'];
    }
    if ($newPassword !== $confirm) {
        return ['success' => false, 'error' => 'Passwords do not match.'];
    }

    set_user_password($targetId, $newPassword);
    return ['success' => true];
}

function handle_delete_user(array $post, array $currentUser): array {
    $targetId = (int) ($post['user_id'] ?? 0);
    if ($targetId <= 0 || !get_user_by_id($targetId)) {
        return ['success' => false, 'error' => 'User not found.'];
    }
    if ($targetId === (int) $currentUser['id']) {
        return ['success' => false, 'error' => "You can't delete your own account while logged in as it."];
    }
    if (count_users() <= 1) {
        return ['success' => false, 'error' => 'At least one user account must remain.'];
    }

    delete_user($targetId);
    return ['success' => true];
}

function handle_users_action(string $action, array $post, array $currentUser): array {
    return match ($action) {
        'create_user' => handle_create_user($post, $currentUser),
        'change_password' => handle_change_password($post, $currentUser),
        'delete_user' => handle_delete_user($post, $currentUser),
        default => ['success' => false, 'error' => 'Unknown action'],
    };
}

// Handle AJAX actions (JSON response)
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    header('Content-Type: application/json; charset=utf-8');

    $csrfToken = $_POST['csrf_token'] ?? null;
    if (!verify_csrf_token(is_string($csrfToken) ? $csrfToken : null)) {
        http_response_code(403);
        echo json_encode(['success' => false, 'error' => 'Session expired or invalid security token. Please refresh.']);
        exit;
    }

    $action = is_string($_POST['action'] ?? null) ? $_POST['action'] : '';
    echo json_encode(handle_users_action($action, $_POST, $user));
    exit;
}

$users = get_all_users();
?>
<!doctype html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>User Management | The Old Fitz Admin</title>
  <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=Fraunces:ital,opsz,wght@0,9..144,400;0,9..144,600;1,9..144,400&family=Karla:wght@400;500;600;700&family=IBM+Plex+Mono:wght@400;500&display=swap" rel="stylesheet">
  <link rel="stylesheet" href="../styles.css">
</head>

<body data-csrf-token="<?= htmlspecialchars(get_csrf_token(), ENT_QUOTES, 'UTF-8') ?>" data-current-user-id="<?= (int) $user['id'] ?>">

  <nav class="admin-nav">
    <div class="container admin-nav-inner">
      <a href="index.php" class="admin-brand">
        <img src="../assets/knot.png" alt="" class="knot">
        <span>The Old Fitz Admin</span>
      </a>
      <div class="admin-nav-links">
        <a href="index.php">Announcements</a>
        <a href="menu.php">Menu</a>
        <a href="users.php" class="active">Users</a>
        <a href="hours.php">Hours</a>
      </div>
      <div class="admin-user">
        <span>Logged in as <strong><?= htmlspecialchars($user['username']) ?></strong></span>
        <a href="../" target="_blank" rel="noopener">View Public Site ↗</a>
        <a href="logout.php">Sign Out</a>
      </div>
    </div>
  </nav>

  <main class="dashboard-layout">
    <div class="container">
      <div class="dash-header">
        <p class="eyebrow">Access</p>
        <h1>User Management</h1>
      </div>

      <div class="admin-toolbar">
        <button type="button" class="btn btn-primary btn-sm" id="btn-new-user">+ Add User</button>
      </div>

      <div class="panel">
        <div class="panel-head">
          <h2>
            <span>👤 All Users (<?= count($users) ?>)</span>
          </h2>
        </div>

        <div class="user-grid-wrap">
          <div class="user-grid-head" aria-hidden="true">
            <span class="col-username">Username</span>
            <span class="col-role">Role</span>
            <span class="col-created">Created</span>
            <span class="col-actions">Actions</span>
          </div>
          <div class="user-rows" id="users-rows">
            <?php foreach ($users as $row): ?>
              <div class="user-row" id="user-row-<?= (int) $row['id'] ?>" data-user-id="<?= (int) $row['id'] ?>">
                <div data-label="Username">
                  <strong><?= htmlspecialchars($row['username']) ?></strong>
                  <?php if ((int) $row['id'] === (int) $user['id']): ?>
                    <span class="muted"> (you)</span>
                  <?php endif; ?>
                </div>
                <div data-label="Role"><?= htmlspecialchars(ucfirst($row['role'])) ?></div>
                <div class="font-mono timestamp-cell" data-label="Created"><?= htmlspecialchars($row['created_at']) ?></div>
                <div data-label="Actions">
                  <div class="row-actions">
                    <button type="button" class="btn btn-outline btn-sm btn-change-password"
                      data-id="<?= (int) $row['id'] ?>"
                      data-username="<?= htmlspecialchars($row['username']) ?>">
                      Change Password
                    </button>
                    <?php if ((int) $row['id'] !== (int) $user['id']): ?>
                      <button type="button" class="btn btn-danger btn-sm btn-delete-user" data-id="<?= (int) $row['id'] ?>">
                        Delete
                      </button>
                    <?php endif; ?>
                  </div>
                </div>
              </div>
            <?php endforeach; ?>
          </div>
        </div>
      </div>
    </div>
  </main>

  <!-- Modal Backdrop: Add User -->
  <div class="admin-modal-backdrop" id="modal-user-backdrop" role="dialog" aria-modal="true" aria-labelledby="modal-user-title">
    <div class="admin-modal">
      <div class="modal-header">
        <h2 id="modal-user-title">✨ Add User</h2>
        <button type="button" class="modal-close" aria-label="Close dialog" id="btn-close-user-modal">&times;</button>
      </div>
      <form id="form-user">
        <input type="hidden" name="action" value="create_user">
        <input type="hidden" name="csrf_token" value="<?= htmlspecialchars(get_csrf_token()) ?>">

        <div class="form-grid">
          <div class="form-group full-width">
            <label for="user-field-username">Username</label>
            <input type="text" id="user-field-username" name="username" class="form-control" placeholder="e.g. jsmith" autocomplete="off" required>
          </div>

          <div class="form-group full-width">
            <label for="user-field-role">Role</label>
            <select id="user-field-role" name="role" class="form-control">
              <option value="admin">Admin</option>
              <option value="manager">Manager</option>
              <option value="staff">Staff</option>
            </select>
            <p class="muted field-hint">For your own reference only — every account has the same access.</p>
          </div>

          <div class="form-group">
            <label for="user-field-password">Password</label>
            <div class="password-input-wrap">
              <input type="password" id="user-field-password" name="password" class="form-control" autocomplete="new-password" minlength="8" required>
              <button type="button" class="password-toggle-btn" aria-label="Show password" data-target="user-field-password">
                <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round" class="icon-eye">
                  <path d="M2 12s3-7 10-7 10 7 10 7-3 7-10 7-10-7-10-7Z" />
                  <circle cx="12" cy="12" r="3" />
                </svg>
              </button>
            </div>
          </div>

          <div class="form-group">
            <label for="user-field-confirm">Confirm Password</label>
            <div class="password-input-wrap">
              <input type="password" id="user-field-confirm" name="confirm_password" class="form-control" autocomplete="new-password" minlength="8" required>
              <button type="button" class="password-toggle-btn" aria-label="Show password" data-target="user-field-confirm">
                <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round" class="icon-eye">
                  <path d="M2 12s3-7 10-7 10 7 10 7-3 7-10 7-10-7-10-7Z" />
                  <circle cx="12" cy="12" r="3" />
                </svg>
              </button>
            </div>
          </div>
        </div>

        <div class="form-actions">
          <button type="submit" class="btn btn-primary" id="btn-save-user">Create User</button>
          <button type="button" class="btn btn-outline" id="btn-cancel-user">Cancel</button>
        </div>
      </form>
    </div>
  </div>

  <!-- Modal Backdrop: Change Password -->
  <div class="admin-modal-backdrop" id="modal-password-backdrop" role="dialog" aria-modal="true" aria-labelledby="modal-password-title">
    <div class="admin-modal">
      <div class="modal-header">
        <h2 id="modal-password-title">🔑 Change Password</h2>
        <button type="button" class="modal-close" aria-label="Close dialog" id="btn-close-password-modal">&times;</button>
      </div>
      <form id="form-password">
        <input type="hidden" name="action" value="change_password">
        <input type="hidden" name="csrf_token" value="<?= htmlspecialchars(get_csrf_token()) ?>">
        <input type="hidden" name="user_id" id="password-field-user-id" value="0">

        <div class="form-grid">
          <div class="form-group full-width" id="password-current-group">
            <label for="password-field-current">Current Password</label>
            <div class="password-input-wrap">
              <input type="password" id="password-field-current" name="current_password" class="form-control" autocomplete="current-password">
              <button type="button" class="password-toggle-btn" aria-label="Show password" data-target="password-field-current">
                <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round" class="icon-eye">
                  <path d="M2 12s3-7 10-7 10 7 10 7-3 7-10 7-10-7-10-7Z" />
                  <circle cx="12" cy="12" r="3" />
                </svg>
              </button>
            </div>
          </div>

          <div class="form-group">
            <label for="password-field-new">New Password</label>
            <div class="password-input-wrap">
              <input type="password" id="password-field-new" name="new_password" class="form-control" autocomplete="new-password" minlength="8" required>
              <button type="button" class="password-toggle-btn" aria-label="Show password" data-target="password-field-new">
                <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round" class="icon-eye">
                  <path d="M2 12s3-7 10-7 10 7 10 7-3 7-10 7-10-7-10-7Z" />
                  <circle cx="12" cy="12" r="3" />
                </svg>
              </button>
            </div>
          </div>

          <div class="form-group">
            <label for="password-field-confirm">Confirm New Password</label>
            <div class="password-input-wrap">
              <input type="password" id="password-field-confirm" name="confirm_password" class="form-control" autocomplete="new-password" minlength="8" required>
              <button type="button" class="password-toggle-btn" aria-label="Show password" data-target="password-field-confirm">
                <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round" class="icon-eye">
                  <path d="M2 12s3-7 10-7 10 7 10 7-3 7-10 7-10-7-10-7Z" />
                  <circle cx="12" cy="12" r="3" />
                </svg>
              </button>
            </div>
          </div>
        </div>

        <div class="form-actions">
          <button type="submit" class="btn btn-primary" id="btn-save-password">Update Password</button>
          <button type="button" class="btn btn-outline" id="btn-cancel-password">Cancel</button>
        </div>
      </form>
    </div>
  </div>

  <script src="users.js" defer></script>

</body>

</html>