<?php
/**
 * @package AKSRT
 */

namespace AKSRT\Credits;

defined('ABSPATH') || exit;

trait BalanceServiceRest {


	public function register_routes(): void {
		register_rest_route('aksrt/v1', '/pay/assets', [
			'methods'             => \WP_REST_Server::READABLE,
			'callback'            => [$this, 'rest_asset_snapshot'],
			'permission_callback' => [$this, 'check_asset_rest'],
		]);

		register_rest_route('aksrt/v1', '/pay/balance/charge', [
			[
				'methods'             => \WP_REST_Server::READABLE,
				'callback'            => [$this, 'rest_charge_options'],
				'permission_callback' => [$this, 'check_asset_rest'],
			],
			[
				'methods'             => \WP_REST_Server::CREATABLE,
				'callback'            => [$this, 'rest_charge_create'],
				'permission_callback' => [$this, 'check_asset_rest'],
				'args' => [
					'package' => ['type' => 'string', 'default' => 'custom', 'sanitize_callback' => 'sanitize_text_field'],
					'custom_price' => ['type' => 'string', 'default' => '0', 'pattern' => '^(0|[1-9]\\d*)(?:\\.\\d{1,2})?$'],
					'payment_method' => ['type' => 'string', 'required' => true, 'sanitize_callback' => 'sanitize_key'],
				],
			],
		]);

		register_rest_route('aksrt/v1', '/pay/transfer', [
			[
				'methods'             => \WP_REST_Server::CREATABLE,
				'callback'            => [$this, 'rest_transfer'],
				'permission_callback' => [$this, 'check_asset_rest'],
				'args' => [
					'type' => ['type' => 'string', 'required' => true, 'enum' => ['balance', 'points']],
					'recipient' => ['type' => 'integer', 'required' => true, 'minimum' => 1],
					'amount' => [
						'required' => true,
						'oneOf' => [
							['type' => 'integer', 'minimum' => 1],
							['type' => 'string', 'pattern' => '^(0|[1-9]\\d*)(?:\\.\\d{1,2})?$'],
						],
					],
				],
			],
		]);

		register_rest_route('aksrt/v1', '/pay/transfer/search', [
			[
				'methods'             => \WP_REST_Server::READABLE,
				'callback'            => [$this, 'rest_transfer_search'],
				'permission_callback' => [$this, 'check_asset_rest'],
			],
		]);

		register_rest_route('aksrt/v1', '/pay/balance/points-exchange', [
			[
				'methods'             => \WP_REST_Server::CREATABLE,
				'callback'            => [$this, 'rest_exchange_balance_for_points'],
				'permission_callback' => [$this, 'check_asset_rest'],
				'args' => [
					'product' => ['type' => 'string', 'default' => 'custom', 'maxLength' => 30],
					'custom' => ['type' => 'string', 'default' => '0', 'pattern' => '^\d{1,9}$'],
				],
			],
		]);

	}

	public function rest_asset_snapshot(\WP_REST_Request $request) {
		$user_id = get_current_user_id();
		return rest_ensure_response([
			'success' => true,
			'data' => [
				'wallet_balance' => \AKSRT\Ledger\LedgerService::get_instance()->balance_decimal($user_id),
				'credit_balance' => (string) \AKSRT\Ledger\LedgerService::get_instance()->balance($user_id, \AKSRT\Ledger\AssetType::POINTS),
			],
		]);
	}

	public function check_asset_rest(\WP_REST_Request $request) {
		if (!is_user_logged_in()) {
			return new \WP_Error('aksrt_need_login', __('请先登录', 'aksrt'), ['status' => 401]);
		}
		$nonce = (string) $request->get_header('X-WP-Nonce');
		if ($nonce === '' || !wp_verify_nonce($nonce, 'wp_rest')) {
			return new \WP_Error('aksrt_rest_nonce', __('安全验证失败，请刷新页面后重试', 'aksrt'), ['status' => 403]);
		}
		return true;
	}

	private function balance_feature_enabled(): bool {
		if (!class_exists('\\AKSRT\\Settings\\Settings')) {
			return false;
		}
		$cfg = \AKSRT\Settings\Settings::get_payment_recharge_settings();
		return !empty($cfg['enabled']);
	}


	/**
	 * GET charge options (packages + methods + limits).
	 */
	public function rest_charge_options(\WP_REST_Request $request) {
		if (!$this->balance_feature_enabled()) {
			return new \WP_Error('aksrt_balance_disabled', __('余额功能未启用', 'aksrt'), ['status' => 403]);
		}
		$user_id = get_current_user_id();
		return rest_ensure_response([
			'success' => true,
			'data'    => $this->get_charge_view($user_id),
		]);
	}


	/**
	 * POST create recharge order and initiate payment.
	 */
	public function rest_charge_create(\WP_REST_Request $request) {
		if (!$this->balance_feature_enabled()) {
			return new \WP_Error('aksrt_balance_disabled', __('余额功能未启用', 'aksrt'), ['status' => 403]);
		}
		$user_id = get_current_user_id();
		$operation_key = \AKSRT\Ledger\OperationKey::from_request($request, 'recharge-create', $user_id);
		if (is_wp_error($operation_key)) {
			return $operation_key;
		}
		$params  = $request->get_json_params();
		if (!is_array($params)) {
			$params = $request->get_params();
		}
		$package_key    = sanitize_text_field((string) ($params['package'] ?? 'custom'));
		$custom_price   = isset($params['custom_price']) ? (string) $params['custom_price'] : '0';
		$payment_method = sanitize_key((string) ($params['payment_method'] ?? 'alipay'));

		$result = $this->create_charge_order($user_id, $package_key, $custom_price, $payment_method, $operation_key);
		if (is_wp_error($result)) {
			return $result;
		}
		return rest_ensure_response(['success' => true, 'data' => $result]);
	}


	/**
	 * Transfer balance or points between users.
	 */
	public function rest_transfer(\WP_REST_Request $request) {
		$params = $request->get_json_params();
		if (!is_array($params)) {
			$params = $request->get_params();
		}
		$type        = sanitize_key((string) ($params['type'] ?? 'balance'));
		$recipient   = (int) ($params['recipient'] ?? 0);
		$amount_raw  = $params['amount'] ?? '';
		$from_id     = get_current_user_id();
		$operation_key = \AKSRT\Ledger\OperationKey::from_request($request, 'transfer', $from_id);
		if (is_wp_error($operation_key)) {
			return $operation_key;
		}

		if (!in_array($type, ['balance', 'points'], true)) {
			return new \WP_Error('aksrt_transfer_type', __('转账类型无效', 'aksrt'), ['status' => 400]);
		}
		if ($from_id <= 0) {
			return new \WP_Error('aksrt_need_login', __('请先登录', 'aksrt'), ['status' => 401]);
		}
		if ($recipient <= 0 || $recipient === $from_id) {
			return new \WP_Error('aksrt_transfer_user', __('请选择有效的收款用户', 'aksrt'), ['status' => 400]);
		}
		if (!get_userdata($recipient)) {
			return new \WP_Error('aksrt_transfer_user', __('收款用户不存在', 'aksrt'), ['status' => 404]);
		}

		$cfg = class_exists('\AKSRT\Settings\Settings') ? \AKSRT\Settings\Settings::get_payment_recharge_settings() : [];
		if ($type === 'balance') {
			if (empty($cfg['enabled']) || empty($cfg['transfer']['enabled'])) {
				return new \WP_Error('aksrt_transfer_closed', __('余额转账未开启', 'aksrt'), ['status' => 403]);
			}
			if (class_exists('\AKSRT\Settings\Capabilities') && !\AKSRT\Settings\Capabilities::user_can('balance_transfer', $from_id)) {
				return new \WP_Error('aksrt_transfer_forbidden', __('当前账号无权转账余额', 'aksrt'), ['status' => 403]);
			}
			try {
				$amount = \AKSRT\Ledger\AssetAmount::balance(is_string($amount_raw) ? $amount_raw : '');
			} catch (\InvalidArgumentException $e) {
				return new \WP_Error('aksrt_transfer_amount', __('请输入有效金额', 'aksrt'), ['status' => 400]);
			}
			if ($amount->minor() <= 0) {
				return new \WP_Error('aksrt_transfer_amount', __('请输入有效金额', 'aksrt'), ['status' => 400]);
			}
			$fee_rate = max(0, min(50, (int) ($cfg['transfer']['service_charge'] ?? 0)));
			$fee_minor = $this->percentage_minor($amount->minor(), $fee_rate);

			$from_user = wp_get_current_user();
			$to_user   = get_userdata($recipient);
			$result = \AKSRT\Ledger\LedgerService::get_instance()->transfer(
				$from_id,
				$recipient,
				\AKSRT\Ledger\AssetType::BALANCE,
				$amount->minor(),
				$fee_minor,
				$operation_key,
				'transfer',
				['type' => 'user', 'id' => $recipient],
				sprintf(__('转账给用户[%s]', 'aksrt'), $to_user ? $to_user->display_name : (string) $recipient),
				sprintf(__('来自用户[%s]的转账', 'aksrt'), $from_user->display_name ?: (string) $from_id),
				['fee_rate' => $fee_rate]
			);
			if (is_wp_error($result)) {
				return $result;
			}
			return rest_ensure_response([
				'success' => true,
				'data'    => [
					'message' => __('转账成功', 'aksrt'),
					'reload'  => true,
					'transaction_id' => $result->transaction_id,
					'replayed' => $result->replayed,
					'balance' => \AKSRT\Ledger\AssetAmount::from_minor(\AKSRT\Ledger\AssetType::BALANCE, $result->balance($from_id, \AKSRT\Ledger\AssetType::BALANCE))->decimal(),
				],
			]);
		}

		// points transfer
		if (!class_exists('\AKSRT\Settings\Settings') || !\AKSRT\Settings\Settings::credits_enabled()) {
			return new \WP_Error('aksrt_transfer_closed', __('积分转账未开启', 'aksrt'), ['status' => 403]);
		}
		$points_settings = \AKSRT\Settings\Settings::get_all();
		if (empty($points_settings['points_transfer_s'])) {
			return new \WP_Error('aksrt_transfer_closed', __('积分转账未开启', 'aksrt'), ['status' => 403]);
		}
		if (class_exists('\AKSRT\Settings\Capabilities') && !\AKSRT\Settings\Capabilities::user_can('points_transfer', $from_id)) {
			return new \WP_Error('aksrt_transfer_forbidden', __('当前账号无权转账积分', 'aksrt'), ['status' => 403]);
		}
		if (!is_int($amount_raw) || $amount_raw <= 0) {
			return new \WP_Error('aksrt_transfer_amount', __('请输入有效积分', 'aksrt'), ['status' => 400]);
		}
		$amount = $amount_raw;
		$min_amount = max(1, (int) ($points_settings['points_transfer_min'] ?? 1));
		if ($amount < $min_amount) {
			return new \WP_Error('aksrt_transfer_minimum', sprintf(__('单笔转账至少需要 %d 积分', 'aksrt'), $min_amount), ['status' => 400]);
		}
		$fee_rate = max(0, min(50, (int) ($points_settings['points_service_charge'] ?? 0)));
		$fee = $this->percentage_minor($amount, $fee_rate);
		$from_user = wp_get_current_user();
		$to_user   = get_userdata($recipient);
		$result = \AKSRT\Ledger\LedgerService::get_instance()->transfer(
			$from_id,
			$recipient,
			\AKSRT\Ledger\AssetType::POINTS,
			$amount,
			$fee,
			$operation_key,
			'transfer',
			['type' => 'user', 'id' => $recipient],
			sprintf(__('转账给用户[%s]', 'aksrt'), $to_user ? $to_user->display_name : (string) $recipient),
			sprintf(__('来自用户[%s]的转账', 'aksrt'), $from_user->display_name ?: (string) $from_id),
			['fee_rate' => $fee_rate]
		);
		if (is_wp_error($result)) {
			return $result;
		}
		return rest_ensure_response([
			'success' => true,
			'data'    => [
				'message' => __('转账成功', 'aksrt'),
				'reload'  => true,
				'transaction_id' => $result->transaction_id,
				'replayed' => $result->replayed,
				'balance' => $result->balance($from_id, \AKSRT\Ledger\AssetType::POINTS),
			],
		]);
	}


	public function rest_transfer_search(\WP_REST_Request $request) {
		$s = sanitize_text_field((string) $request->get_param('s'));
		if (mb_strlen($s) < 1) {
			return rest_ensure_response(['success' => true, 'data' => ['users' => []]]);
		}
		$exclude = [get_current_user_id()];
		$q = new \WP_User_Query([
			'search'         => '*' . $s . '*',
			'search_columns' => ['user_login', 'user_nicename', 'display_name', 'user_email'],
			'exclude'        => $exclude,
			'number'         => 20,
			'fields'         => ['ID', 'display_name', 'user_login'],
		]);
		$users = [];
		foreach ((array) $q->get_results() as $u) {
			$users[] = [
				'id'           => (int) $u->ID,
				'display_name' => (string) $u->display_name,
				'user_login'   => (string) $u->user_login,
				'avatar'       => get_avatar_url((int) $u->ID, ['size' => 48]),
			];
		}
		return rest_ensure_response(['success' => true, 'data' => ['users' => $users]]);
	}


	/**
	 * Buy points with cash-wallet balance (积分购买弹窗 · 余额支付).
	 *
	 * Body: { product: 'custom'|<package_key>, custom?: <points int> }
	 * 自定义按汇率折算支付金额；商品按配置销售金额支付（参考主题同款语义）。
	 */
	public function rest_exchange_balance_for_points(\WP_REST_Request $request) {
		if (!$this->balance_feature_enabled()) {
			return new \WP_Error('aksrt_balance_disabled', __('余额功能未启用', 'aksrt'), ['status' => 403]);
		}
		if (!class_exists('AKSRT\\Settings\\Settings') || !\AKSRT\Settings\Settings::credits_enabled()) {
			return new \WP_Error('aksrt_points_disabled', __('积分功能未启用', 'aksrt'), ['status' => 403]);
		}
		$cfg = \AKSRT\Settings\Settings::get_payment_recharge_settings();
		$exchange = is_array($cfg['points_exchange'] ?? null) ? $cfg['points_exchange'] : [];
		if (empty($exchange['enabled'])) {
			return new \WP_Error('aksrt_exchange_closed', __('余额兑换积分未开启', 'aksrt'), ['status' => 403]);
		}
		$params = $request->get_json_params();
		if (!is_array($params)) {
			$params = $request->get_params();
		}
		$rate = max(1, (int) ($exchange['rate'] ?? 100));
		$daily_max = max(1, (int) ($exchange['daily_max_points'] ?? 100000));
		$product_key = sanitize_key((string) ($params['product'] ?? 'custom'));
		$points = 0;
		$pay_minor = 0;
		$product_title = '';
		if ($product_key !== '' && $product_key !== 'custom') {
			$found = null;
			foreach ($this->parse_points_packages((string) ($exchange['products_raw'] ?? '')) as $pkg) {
				if ((string) ($pkg['key'] ?? '') === $product_key) {
					$found = $pkg;
					break;
				}
			}
			if (!$found) {
				return new \WP_Error('aksrt_exchange_product', __('积分商品无效', 'aksrt'), ['status' => 400]);
			}
			$points = (int) $found['points'];
			try {
				$pay_minor = \AKSRT\Ledger\AssetAmount::balance((string) $found['pay_price'])->minor();
			} catch (\InvalidArgumentException $e) {
				$pay_minor = 0;
			}
			$product_title = (string) $found['title'];
		} else {
			$product_key = 'custom';
			$points = absint((string) ($params['custom'] ?? '0'));
			$min_points = max(1, (int) ($exchange['min_points'] ?? 100));
			if ($points <= 0) {
				return new \WP_Error('aksrt_exchange_amount', __('请输入需购买的积分数额', 'aksrt'), ['status' => 400]);
			}
			if ($points < $min_points) {
				return new \WP_Error('aksrt_exchange_min', sprintf(__('最低购买%d积分', 'aksrt'), $min_points), ['status' => 400]);
			}
			// 自定义按汇率折算支付金额（参考主题语义：积分 * 100 / 汇率 后四舍五入）。
			// 纯整数实现：intdiv(2a + b, 2b) 等价于 a / b 四舍五入，避免浮点。
			$pay_minor = intdiv($points * 200 + $rate, $rate * 2);
			$product_title = sprintf(__('购买 %d 积分', 'aksrt'), $points);
		}
		if ($points <= 0) {
			return new \WP_Error('aksrt_exchange_product', __('积分商品无效', 'aksrt'), ['status' => 400]);
		}
		if ($pay_minor <= 0) {
			return new \WP_Error('aksrt_exchange_precision', __('支付金额无效', 'aksrt'), ['status' => 400]);
		}
		if ($points > $daily_max) {
			return new \WP_Error('aksrt_exchange_daily_limit', sprintf(__('今日购买积分上限为 %d', 'aksrt'), $daily_max), ['status' => 400]);
		}
		$user_id = get_current_user_id();
		$operation_key = \AKSRT\Ledger\OperationKey::from_request($request, 'points-exchange', $user_id);
		if (is_wp_error($operation_key)) {
			return $operation_key;
		}
		$site_now = current_datetime();
		$start = (clone $site_now)->setTime(0, 0, 0);
		$end = (clone $start)->modify('+1 day');
		$utc = new \DateTimeZone('UTC');
		$start_gmt = $start->setTimezone($utc)->format('Y-m-d H:i:s.u');
		$end_gmt = $end->setTimezone($utc)->format('Y-m-d H:i:s.u');
		$guard = static function () use ($user_id, $points, $daily_max, $start_gmt, $end_gmt) {
			$used = \AKSRT\Ledger\LedgerQuery::get_instance()->sum_credits($user_id, 'points_exchange', $start_gmt, $end_gmt);
			if ($used + $points > $daily_max) {
				return new \WP_Error('aksrt_exchange_daily_limit', sprintf(__('今日购买积分上限为 %d，当前还可购买 %d', 'aksrt'), $daily_max, max(0, $daily_max - $used)), ['status' => 400]);
			}
			return true;
		};
		if (!class_exists('\\AKSRT\\Payment\\OrderRepository')) {
			return new \WP_Error('aksrt_order_unavailable', __('订单服务不可用', 'aksrt'), ['status' => 500]);
		}
		$pay_decimal = \AKSRT\Ledger\AssetAmount::decimal_from_minor($pay_minor);
		$note = wp_json_encode([
			'points_exchange' => 1,
			'points' => $points,
			'product' => $product_key,
			'product_title' => $product_title,
		], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
		$repo = \AKSRT\Payment\OrderRepository::get_instance();
		$existing_order = $repo->get_by_request_key($operation_key);
		$is_new_order = !is_array($existing_order);
		if (is_array($existing_order)) {
			$existing_meta = json_decode((string) ($existing_order['note'] ?? ''), true);
			$existing_meta = is_array($existing_meta) ? $existing_meta : [];
			if ((int) ($existing_order['user_id'] ?? 0) !== $user_id
				|| sanitize_key((string) ($existing_order['product_type'] ?? '')) !== \AKSRT\Core\DomainModel::ORDER_PRODUCT_POINTS
				|| (string) ($existing_order['amount'] ?? '') !== $pay_decimal
				|| sanitize_key((string) ($existing_order['currency'] ?? '')) !== 'cny'
				|| sanitize_key((string) ($existing_order['payment_method'] ?? '')) !== 'balance'
				|| (int) ($existing_meta['points'] ?? 0) !== $points
				|| (string) ($existing_meta['product'] ?? '') !== $product_key
			) {
				return new \WP_Error('aksrt_ledger_idempotency_conflict', __('相同操作标识已用于其他积分购买请求', 'aksrt'), ['status' => 409]);
			}
			$order_number = (string) ($existing_order['order_number'] ?? '');
		} else {
			$order_number = $repo->allocate_order_number();
		}
		if ($order_number === '') {
			return new \WP_Error('aksrt_order_create_failed', __('积分订单创建失败', 'aksrt'), ['status' => 500]);
		}
		$business_mutation = static function (int $transaction_id) use ($is_new_order, $repo, $user_id, $pay_decimal, $points, $operation_key, $order_number, $note) {
			if (!$is_new_order) {
				return true;
			}
			$created = $repo->create([
				'order_number' => $order_number,
				'user_id' => $user_id,
				'product_type' => \AKSRT\Core\DomainModel::ORDER_PRODUCT_POINTS,
				'product_id' => 0,
				'amount' => $pay_decimal,
				'currency' => 'CNY',
				'status' => \AKSRT\Payment\Order::STATUS_PAID,
				'payment_method' => 'balance',
				'payment_transaction_id' => 'ledger_' . $transaction_id,
				'paid_at' => current_time('mysql'),
				'note' => is_string($note) ? $note : '',
				'request_key' => $operation_key,
			]);
			if ($created !== $order_number) {
				return new \WP_Error('aksrt_order_create_failed', __('积分订单创建失败', 'aksrt'), ['status' => 500]);
			}
			if (class_exists('\\AKSRT\\Payment\\CommissionLedger')) {
				return \AKSRT\Payment\CommissionLedger::get_instance()->record_points_exchange($user_id, $pay_decimal, $points, $operation_key, $order_number);
			}
			return true;
		};
		$result = \AKSRT\Ledger\LedgerService::get_instance()->exchange(
			$user_id,
			$pay_minor,
			$points,
			$operation_key,
			'points_exchange',
			['type' => 'order', 'key' => $order_number],
			sprintf(__('余额购买 %d 积分', 'aksrt'), $points),
			['rate' => $rate, 'product' => $product_key],
			$guard,
			$business_mutation
		);
		if (is_wp_error($result)) {
			return $result;
		}
		return rest_ensure_response(['success' => true, 'data' => [
			'message' => sprintf(__('购买成功，获得 %d 积分', 'aksrt'), $points),
			'transaction_id' => $result->transaction_id,
			'replayed' => $result->replayed,
			'wallet_balance' => \AKSRT\Ledger\AssetAmount::from_minor(\AKSRT\Ledger\AssetType::BALANCE, $result->balance($user_id, \AKSRT\Ledger\AssetType::BALANCE))->decimal(),
			'credit_balance' => $result->balance($user_id, \AKSRT\Ledger\AssetType::POINTS),
			'points' => $points,
			'order_number' => $order_number,
			'reload' => true,
		]]);
	}

	private function percentage_minor(int $amount, int $rate): int {
		if ($amount <= 0 || $rate <= 0) {
			return 0;
		}
		return (intdiv($amount, 100) * $rate) + intdiv(($amount % 100) * $rate, 100);
	}

}