<?php

namespace Modules\EcommerceFinance\Services;

use InvalidArgumentException;

/**
 * 厂家记账扣款判定（2026-10-19 由财务确认）：
 *
 * - 记账原因一级为“厂家记账”：按供应商的厂家记账配置判定，仅“正常记账”的供应商作为扣款项；
 * - 记账原因一级为“仓库记账”：只有订单发货仓库为“某某代发仓”且二级原因含“仓库发错货”时，
 *   才可作为厂家记账扣款项（供应商配置为“不记账”时仍不扣）；其余仓库记账一律不作为扣款项；
 * - 配置表中没有的供应商（含配置不在生效期内）视同正常记账，作为可扣款项（2026-10-19 财务更正）；
 * - 工单未带供应商、或多件商品分属不同供应商且判定不一致的，标记“待确认”，不计入扣款。
 */
class SupplierBookkeepingDeductionRule
{
    public const MODE_NONE = 'none';
    public const MODE_DROPSHIP_WRONG = 'dropship_wrong';
    public const MODE_NORMAL = 'normal';

    public const MODES = [
        self::MODE_NORMAL => '正常记账',
        self::MODE_DROPSHIP_WRONG => '仅代发仓发错货记账',
        self::MODE_NONE => '不记账',
    ];

    public const STATUS_DEDUCT = '扣款';
    public const STATUS_SKIP = '不扣款';
    public const STATUS_REVIEW = '待确认';

    public const STATUSES = [self::STATUS_DEDUCT, self::STATUS_SKIP, self::STATUS_REVIEW];

    public const DROPSHIP_WAREHOUSE_KEYWORD = '代发仓';
    public const WAREHOUSE_WRONG_KEYWORD = '仓库发错货';

    /**
     * 解析配置表中“厂家是否记账”原文，例如“代发仓发货错需记账，其他原因均不记账”“不记账（2025.3月-2027.12.30）”。
     *
     * @return array{mode:string,effective_from:?string,effective_to:?string}
     */
    public static function parseRuleText(string $text): array
    {
        $normalized = str_replace(['(', ')', ' ', '　'], ['（', '）', '', ''], trim($text));
        if ($normalized === '') {
            throw new InvalidArgumentException('厂家是否记账为空。');
        }
        $label = array_search($normalized, self::MODES, true);
        if (is_string($label)) {
            return ['mode' => $label, 'effective_from' => null, 'effective_to' => null];
        }
        if (str_contains($normalized, '代发仓') && (str_contains($normalized, '发货错') || str_contains($normalized, '发错货'))) {
            $mode = self::MODE_DROPSHIP_WRONG;
        } elseif (str_starts_with($normalized, '正常记账')) {
            $mode = self::MODE_NORMAL;
        } elseif (str_starts_with($normalized, '不记账')) {
            $mode = self::MODE_NONE;
        } else {
            throw new InvalidArgumentException('无法识别的记账方式：' . $text);
        }

        [$from, $to] = [null, null];
        $date = '(\d{4})[.\/年](\d{1,2})月?(?:[.\/](\d{1,2})日?)?';
        if (preg_match('/（' . $date . '[-—~至]+' . $date . '）/u', $normalized, $m)) {
            $from = self::date((int) $m[1], (int) $m[2], ($m[3] ?? '') === '' ? 1 : (int) $m[3]);
            $to = self::date((int) $m[4], (int) $m[5], ($m[6] ?? '') === '' ? null : (int) $m[6]);
            if ($from > $to) {
                throw new InvalidArgumentException('生效期开始晚于结束：' . $text);
            }
        } elseif (str_contains($normalized, '（')) {
            throw new InvalidArgumentException('无法识别的生效期：' . $text);
        }

        return ['mode' => $mode, 'effective_from' => $from, 'effective_to' => $to];
    }

    /** 配置的展示文字，例如“不记账（2025-03-01 至 2026-02-28）”。 */
    public static function describe(array|object $config): string
    {
        $config = (array) $config;
        $label = self::MODES[$config['mode']] ?? (string) $config['mode'];
        $from = $config['effective_from'] ?? null;
        $to = $config['effective_to'] ?? null;
        if ($from === null && $to === null) {
            return $label;
        }

        return $label . '（' . ($from ?? '不限') . ' 至 ' . ($to ?? '不限') . '）';
    }

    /**
     * @param array<string,mixed> $row 厂家记账明细行
     * @param array<string,array<string,mixed>|object> $configs 供应商名称 => 生效中的配置
     * @return array{supplier_config:string,deduction_status:string,deduction_basis:string}
     */
    public static function decide(array $row, array $configs): array
    {
        $level1 = (string) ($row['reason_level_1'] ?? '');
        $level2 = (string) ($row['reason_level_2'] ?? '');
        $date = substr((string) ($row['started_at'] ?? ''), 0, 10);
        $suppliers = array_values(array_unique(array_filter(array_map('trim', explode("\n", (string) ($row['supplier'] ?? '')))), SORT_STRING));

        $found = [];
        foreach ($suppliers as $supplier) {
            $found[$supplier] = isset($configs[$supplier]) ? (array) $configs[$supplier] : null;
        }
        $configText = implode("\n", array_map(static fn (?array $config): string => $config === null ? '未在配置表（按正常记账）' : self::describe($config), $found));

        if ($level1 === '仓库记账') {
            $warehouse = (string) ($row['shipping_warehouse'] ?? '');
            if (! str_contains($warehouse, self::DROPSHIP_WAREHOUSE_KEYWORD) || ! str_contains($level2, self::WAREHOUSE_WRONG_KEYWORD)) {
                return self::result($configText, self::STATUS_SKIP, '仓库记账仅“代发仓 + 仓库发错货”作为厂家扣款，本单不扣');
            }
        } elseif ($level1 !== '厂家记账') {
            return self::result($configText, self::STATUS_SKIP, '非厂家记账/仓库记账原因');
        }

        if ($suppliers === []) {
            return self::result('', self::STATUS_REVIEW, '工单未带供应商，无法判定扣款，请人工确认');
        }

        $outcomes = [];
        foreach ($found as $supplier => $config) {
            $outcomes[$supplier] = self::outcome($level1, $config, $date);
        }
        $statuses = array_values(array_unique(array_column($outcomes, 0)));
        if (count($statuses) > 1) {
            $detail = implode('；', array_map(static fn (string $supplier, array $o): string => $supplier . '：' . $o[0], array_keys($outcomes), $outcomes));

            return self::result($configText, self::STATUS_REVIEW, '多个供应商判定不一致，请人工确认（' . $detail . '）');
        }

        return self::result($configText, $statuses[0], reset($outcomes)[1]);
    }

    /** @return array{0:string,1:string} [判定, 说明] */
    private static function outcome(string $level1, ?array $config, string $date): array
    {
        if ($config === null) {
            return [self::STATUS_DEDUCT, $level1 === '厂家记账' ? '供应商不在配置表，按正常记账扣款' : '代发仓发错货，记厂家扣款（供应商不在配置表）'];
        }
        $from = $config['effective_from'] ?? null;
        $to = $config['effective_to'] ?? null;
        if (($from !== null && $date < $from) || ($to !== null && $date > $to)) {
            return [self::STATUS_DEDUCT, '发起日期不在配置生效期内（' . self::describe($config) . '），按正常记账扣款'];
        }

        return match ($config['mode']) {
            self::MODE_NONE => [self::STATUS_SKIP, '供应商配置为不记账'],
            self::MODE_NORMAL => $level1 === '厂家记账'
                ? [self::STATUS_DEDUCT, '供应商正常记账']
                : [self::STATUS_DEDUCT, '代发仓发错货，记厂家扣款'],
            self::MODE_DROPSHIP_WRONG => $level1 === '仓库记账'
                ? [self::STATUS_DEDUCT, '代发仓发错货，记厂家扣款']
                : [self::STATUS_SKIP, '供应商仅代发仓发错货记账，其他原因不记账'],
            default => [self::STATUS_REVIEW, '无法识别的记账方式，请人工确认'],
        };
    }

    private static function result(string $config, string $status, string $basis): array
    {
        return ['supplier_config' => $config, 'deduction_status' => $status, 'deduction_basis' => $basis];
    }

    private static function date(int $year, int $month, ?int $day): string
    {
        if ($month < 1 || $month > 12) {
            throw new InvalidArgumentException('生效期月份无效。');
        }
        $last = (int) date('t', mktime(0, 0, 0, $month, 1, $year));
        $day ??= $last;
        if ($day < 1 || $day > $last) {
            throw new InvalidArgumentException('生效期日期无效。');
        }

        return sprintf('%04d-%02d-%02d', $year, $month, $day);
    }
}