<?php
/**
 * AKSRT Shipping — 物流管理
 *
 * 管理订单发货、物流单号、发货状态。
 *
 * @package AKSRT
 */

defined('ABSPATH') || exit;

class AKSRT_Shipping {
    use AKSRT_Shipping_Part_1;
    use AKSRT_Shipping_Part_2;


    private static $instance = null;

    const STATUS_SHIPPED   = 'shipped';
    const STATUS_IN_TRANSIT = 'in_transit';
    const STATUS_DELIVERED = 'delivered';
    const STATUS_RETURNED  = 'returned';

    public static function get_instance(): self {
        if (null === self::$instance) {
            self::$instance = new self();
        }
        return self::$instance;
    }

    private function table(): string {
        return AKSRT_DB_Migrator::table('order_shipping');
    }

    /**
     * 创建发货记录
     */
    public function create(array $data): int {
        global $wpdb;

        $order_number = sanitize_text_field((string) ($data['order_number'] ?? ''));
        $carrier      = sanitize_text_field((string) ($data['carrier'] ?? ''));
        $tracking_no  = sanitize_text_field((string) ($data['tracking_no'] ?? ''));
        $note         = sanitize_textarea_field((string) ($data['note'] ?? ''));
        $operator_id  = (int) ($data['operator_id'] ?? 0);

        if ($order_number === '' || $carrier === '' || $tracking_no === '') {
            return 0;
        }

        $result = $wpdb->insert($this->table(), [
            'order_number' => $order_number,
            'carrier'      => $carrier,
            'tracking_no'  => $tracking_no,
            'status'       => self::STATUS_SHIPPED,
            'note'         => $note,
            'operator_id'  => $operator_id ?: null,
            'created_at'   => current_time('mysql'),
        ]);

        $insert_id = $result ? (int) $wpdb->insert_id : 0;

        if ($insert_id > 0) {
            $this->sync_order_status($order_number, self::STATUS_SHIPPED, sprintf(
                __('发货记录已创建：%1$s %2$s', 'aksrt'),
                $this->get_carrier_label($carrier),
                $tracking_no
            ));

            // R68: Email notification on shipping creation (§6.6)
            $this->send_shipping_notification($order_number, $carrier, $tracking_no, $note);
        }

        return $insert_id;
    }

    /**
     * 获取发货记录列表
     */
    public function get_list(array $args = []): array {
        global $wpdb;

        $limit  = max(1, min(100, (int) ($args['limit'] ?? 20)));
        $offset = max(0, (int) ($args['offset'] ?? 0));
        $include_order_context = !empty($args['include_order_context']);
        $status = sanitize_key((string) ($args['status'] ?? ''));
        $order_number = sanitize_text_field((string) ($args['order_number'] ?? ''));
        $date_from = sanitize_text_field((string) ($args['date_from'] ?? ''));
        $date_to = sanitize_text_field((string) ($args['date_to'] ?? ''));
        $tracking_no = sanitize_text_field((string) ($args['tracking_no'] ?? ''));

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

        if ($status !== '') {
            $where[] = 'status = %s';
            $params[] = $status;
        }
        if ($order_number !== '') {
            $where[] = 'order_number = %s';
            $params[] = $order_number;
        }
        if ($tracking_no !== '') {
            $where[] = 'tracking_no LIKE %s';
            $params[] = '%' . $wpdb->esc_like($tracking_no) . '%';
        }
        if ($date_from !== '') {
            $where[] = 'created_at >= %s';
            $params[] = $date_from . ' 00:00:00';
        }
        if ($date_to !== '') {
            $where[] = 'created_at <= %s';
            $params[] = $date_to . ' 23:59:59';
        }

        $where_sql = $where ? 'WHERE ' . implode(' AND ', $where) : '';

        $count_sql = "SELECT COUNT(*) FROM {$this->table()} {$where_sql}";
        $total = $params ? (int) $wpdb->get_var($wpdb->prepare($count_sql, $params)) : (int) $wpdb->get_var($count_sql);

        $sql = "SELECT * FROM {$this->table()} {$where_sql} ORDER BY created_at DESC LIMIT %d OFFSET %d";
        $params[] = $limit;
        $params[] = $offset;

        $items = $wpdb->get_results($wpdb->prepare($sql, $params), ARRAY_A);
        $items = array_map([$this, 'decorate_record'], (array) $items);

        if ($include_order_context && !empty($items) && class_exists('AKSRT_Order_Repository')) {
            $contexts = AKSRT_Order_Repository::get_instance()->get_admin_order_context_map(array_column($items, 'order_number'));
            foreach ($items as &$item) {
                $item['order_context'] = $contexts[(string) ($item['order_number'] ?? '')] ?? [];
            }
            unset($item);
        }

        return [
            'items'     => $items ?: [],
            'total'     => $total,
            'page'      => floor($offset / $limit) + 1,
            'max_pages' => ceil($total / $limit),
        ];
    }

    /**
     * 获取单个发货记录
     */
    public function get(int $id): ?array {
        global $wpdb;
        $row = $wpdb->get_row($wpdb->prepare(
            "SELECT * FROM {$this->table()} WHERE id = %d",
            $id
        ), ARRAY_A);
        return $row ? $this->decorate_record($row) : null;
    }

    /**
     * 获取订单的发货记录
     */
    public function get_by_order(string $order_number): array {
        global $wpdb;
        $items = $wpdb->get_results($wpdb->prepare(
            "SELECT * FROM {$this->table()} WHERE order_number = %s ORDER BY created_at DESC",
            $order_number
        ), ARRAY_A);
        return array_map([$this, 'decorate_record'], (array) $items);
    }

    /**
     * 获取单个发货记录并附带订单上下文。
     */
    public function get_with_order_context(int $id): ?array {
        $record = $this->get($id);
        if (!$record) {
            return null;
        }

        $record['order_context'] = class_exists('AKSRT_Order_Repository')
            ? AKSRT_Order_Repository::get_instance()->get_admin_order_context((string) ($record['order_number'] ?? ''))
            : [];

        return $record;
    }

    /**
     * @param array<int, string> $order_numbers
     * @return array<string, array<string, mixed>>
     */
    public function get_summary_map(array $order_numbers): array {
        global $wpdb;

        $order_numbers = array_values(array_unique(array_filter(array_map(
            static function ($order_number): string {
                return sanitize_text_field((string) $order_number);
            },
            $order_numbers
        ))));

        if (empty($order_numbers)) {
            return [];
        }

        $map = [];
        foreach ($order_numbers as $order_number) {
            $map[$order_number] = [
                'count' => 0,
                'latest' => [],
            ];
        }

        $placeholders = implode(', ', array_fill(0, count($order_numbers), '%s'));
        $sql = "SELECT * FROM {$this->table()} WHERE order_number IN ({$placeholders}) ORDER BY created_at DESC, id DESC";
        $rows = $wpdb->get_results($wpdb->prepare($sql, $order_numbers), ARRAY_A);

        foreach ((array) $rows as $row) {
            $record = $this->decorate_record($row);
            $order_number = (string) ($record['order_number'] ?? '');

            if (!isset($map[$order_number])) {
                continue;
            }

            $map[$order_number]['count']++;
            if (empty($map[$order_number]['latest'])) {
                $map[$order_number]['latest'] = $this->build_summary_item($record);
            }
        }

        return $map;
    }

    public function batch_update_status(array $ids, string $new_status, string $note = '', int $operator_id = 0): array {
        $ids = array_values(array_unique(array_filter(array_map('intval', $ids))));
        $result = [
            'updated_ids' => [],
            'failed' => [],
        ];

        foreach ($ids as $id) {
            $record = $this->get($id);
            if (!$record) {
                $result['failed'][] = [
                    'id' => $id,
                    'reason' => __('发货记录不存在', 'aksrt'),
                ];
                continue;
            }

            if (!$this->can_transition_status((string) ($record['status'] ?? ''), $new_status)) {
                $result['failed'][] = [
                    'id' => $id,
                    'reason' => __('当前状态不允许批量更新到目标状态', 'aksrt'),
                ];
                continue;
            }

            if ($this->update_status($id, $new_status, $note, $operator_id)) {
                $result['updated_ids'][] = $id;
            } else {
                $result['failed'][] = [
                    'id' => $id,
                    'reason' => __('状态更新失败', 'aksrt'),
                ];
            }
        }

        return $result;
    }

    /**
     * 更新发货状态
     */
    public function update_status(int $id, string $new_status, string $note = '', int $operator_id = 0): bool {
        global $wpdb;

        $record = $this->get($id);
        if (!$record) {
            return false;
        }

        $valid = [self::STATUS_SHIPPED, self::STATUS_IN_TRANSIT, self::STATUS_DELIVERED, self::STATUS_RETURNED];
        if (!in_array($new_status, $valid, true)) return false;
        if (!$this->can_transition_status((string) ($record['status'] ?? ''), $new_status)) {
            return false;
        }

        $update = [
            'status'    => $new_status,
            'updated_at' => current_time('mysql'),
        ];

        if ($note !== '') {
            $update['note'] = sanitize_textarea_field($note);
        }
        if ($operator_id > 0) {
            $update['operator_id'] = $operator_id;
        }
        if ($new_status === self::STATUS_DELIVERED) {
            $update['delivered_at'] = current_time('mysql');
        }

        $updated = (bool) $wpdb->update($this->table(), $update, ['id' => $id]);
        if ($updated) {
            $this->sync_order_status(
                (string) ($record['order_number'] ?? ''),
                $new_status,
                $note !== '' ? $note : sprintf(__('物流状态更新为：%s', 'aksrt'), $this->get_status_label($new_status))
            );
        }

        return $updated;
    }

    /**
     * 获取统计
     */
    public function get_stats(): array {
        global $wpdb;
        $table = $this->table();

        $counts = $wpdb->get_results(
            "SELECT status, COUNT(*) as cnt FROM {$table} GROUP BY status",
            ARRAY_A
        );
        $counts = array_column($counts, 'cnt', 'status');

        $stats = [
            'total'      => 0,
            'shipped'    => 0,
            'in_transit' => 0,
            'delivered'  => 0,
            'returned'   => 0,
        ];

        foreach ($counts as $status => $cnt) {
            if (isset($stats[$status])) {
                $stats[$status] = (int) $cnt;
            }
            $stats['total'] += (int) $cnt;
        }

        return $stats;
    }

    /**
     * 获取常用快递公司列表
     */
    public static function get_carrier_options(): array {
        return [
            ['value' => 'sf',    'label' => '顺丰速运'],
            ['value' => 'yd',    'label' => '韵达快递'],
            ['value' => 'zt',    'label' => '中通快递'],
            ['value' => 'yt',    'label' => '圆通速递'],
            ['value' => 'sto',   'label' => '申通快递'],
            ['value' => 'jd',    'label' => '京东物流'],
            ['value' => 'ems',   'label' => 'EMS'],
            ['value' => 'db',    'label' => '德邦快递'],
            ['value' => 'yunda', 'label' => '韵达快递'],
            ['value' => 'other', 'label' => '其他'],
        ];
    }
    public static function get_status_options(): array {
        return [
            ['value' => self::STATUS_SHIPPED, 'label' => __('已发货', 'aksrt')],
            ['value' => self::STATUS_IN_TRANSIT, 'label' => __('运输中', 'aksrt')],
            ['value' => self::STATUS_DELIVERED, 'label' => __('已签收', 'aksrt')],
            ['value' => self::STATUS_RETURNED, 'label' => __('已退回', 'aksrt')],
        ];
    }

    /**
     * Send email notification to order customer when shipping record is created.
     */
}