<?php

namespace Modules\EcommerceFinance\Services;

use Illuminate\Database\DatabaseManager;
use Illuminate\Support\Carbon;
use Illuminate\Support\Str;
use InvalidArgumentException;
use RuntimeException;
use Throwable;

class JdDailyBillImporter
{
    public const PAYLOAD_FIELDS = [
        'online_order_no' => '线上单号', 'document_no' => '单据编号',
        'merchant_order_no' => '商户订单号', 'document_type' => '单据类型',
        'product_id' => '商品编码', 'product_name' => '商品名称',
        'cost_happened_at' => '费用发生时间', 'cost_name' => '费用项',
        'currency' => '币种', 'settle_remark' => '钱包结算备注',
        'shop_no' => '店铺号', 'jd_shop_no' => '京东门店编码',
        'brand_shop_no' => '品牌门店编号', 'shop_name' => '门店名称',
        'account_code' => '账户代码',
    ];

    public function __construct(private readonly DatabaseManager $databases) {}

    public function import(string $path, string $month, int $expectedCount, string $expectedIncome, string $expectedExpense, ?string $through = null): array
    {
        if (! preg_match('/^\d{4}-(0[1-9]|1[0-2])$/', $month) || $expectedCount < 1) {
            throw new InvalidArgumentException('必须指定完整月份及核对笔数。');
        }
        $expectedIn = $this->cents($expectedIncome);
        $expectedOut = $this->cents($expectedExpense);
        $start = $month . '-01';
        $end = Carbon::parse($start)->addMonth()->format('Y-m-d');
        if ($through !== null) {
            $date = \DateTimeImmutable::createFromFormat('!Y-m-d', $through);
            if (! $date || $date->format('Y-m-d') !== $through || $through < $start || $through >= $end) {
                throw new InvalidArgumentException('截止日期必须是指定月份内的有效日期。');
            }
            $end = $date->modify('+1 day')->format('Y-m-d');
        }
        $file = fopen($path, 'rb');
        if ($file === false) throw new RuntimeException('无法读取京东日账单明细。');
        $db = $this->databases->connection(config('upstream_mirrors.connection', 'business_mirror'));
        $generation = (string) Str::uuid();
        $count = $income = $expense = 0;
        $batch = [];
        try {
            $headers = fgetcsv($file);
            if (! is_array($headers)) throw new InvalidArgumentException('明细为空。');
            $headers[0] = preg_replace('/^\xEF\xBB\xBF/', '', $headers[0]);
            $required = array_merge(['记录编码', '店铺', '账单项目', '订单编号', '费用结算时间', '收入金额', '支出金额'], array_values(self::PAYLOAD_FIELDS));
            if (count(array_unique($headers)) !== count($headers) || array_diff($required, $headers)) {
                throw new InvalidArgumentException('京东日账单字段缺失或重复。');
            }
            while (($values = fgetcsv($file)) !== false) {
                if ($values === [null]) continue;
                if (count($values) !== count($headers)) throw new InvalidArgumentException('明细列数不一致。');
                $r = array_combine($headers, $values);
                $code = trim($r['记录编码']);
                if (! preg_match('/^\d{1,64}$/', $code)) throw new InvalidArgumentException('记录编码为空或失真。');
                $time = $this->dateTime($r['费用结算时间']);
                if ($time === null || $time < $start || $time >= $end || trim($r['店铺']) === '') {
                    throw new InvalidArgumentException('费用结算时间或店铺不符合导入范围。');
                }
                if (trim($r['币种']) !== 'CNY') throw new InvalidArgumentException('不能合并不同币种的账单金额。');
                $in = $this->cents($r['收入金额']);
                $out = $this->cents($r['支出金额']);
                $payload = [];
                foreach (self::PAYLOAD_FIELDS as $key => $label) $payload[$key] = $r[$label] !== '' ? $r[$label] : null;
                $payload['cost_happened_at'] = $this->dateTime($r['费用发生时间']);
                $row = [
                    'id' => 'shengsuan-jd:' . $code, 'record_code' => $code,
                    'store_name' => trim($r['店铺']), 'bill_item' => $r['账单项目'],
                    'order_no' => $r['订单编号'], 'occurred_at' => $time,
                    'income' => $this->decimal($in), 'expense' => $this->decimal($out),
                    'custom_remark' => $r['自定义备注'] ?? null, 'remark' => $r['备注'] ?? null,
                    'updated_at' => $this->dateTime($r['修改时间'] ?? ''),
                    'modifier' => $r['修改人'] ?? null, 'payload' => $payload,
                ];
                $batch[] = [
                    'generation' => $generation, 'record_code' => $code, 'store_name' => $row['store_name'],
                    'bill_item' => $row['bill_item'], 'order_no' => $row['order_no'], 'occurred_at' => $time,
                    'income' => $row['income'], 'expense' => $row['expense'],
                    'row_data' => json_encode($row, JSON_UNESCAPED_UNICODE | JSON_THROW_ON_ERROR),
                ];
                $count++; $income += $in; $expense += $out;
                // The generation primary key rejects duplicate source records, including across batches.
                if (count($batch) === 500) {
                    $db->table('jd_daily_bill_rows')->insert($batch);
                    $batch = [];
                }
            }
            if ($count !== $expectedCount || $income !== $expectedIn || $expense !== $expectedOut) {
                throw new InvalidArgumentException('笔数或收支合计不一致，未启用此明细。');
            }
            if ($batch !== []) $db->table('jd_daily_bill_rows')->insert($batch);
            $state = [
                'period_start' => $start, 'period_end' => $end, 'active_generation' => $generation,
                'source_filename' => basename($path), 'source_sha256' => hash_file('sha256', $path),
                'row_count' => $count, 'income' => $this->decimal($income), 'expense' => $this->decimal($expense),
                'imported_at' => now()->format('Y-m-d H:i:s'),
            ];
            // Publish only the reconciled date range; keep the preceding generation for rollback.
            $db->transaction(function () use ($db, $start, $end, $state): void {
                $previous = $db->table('jd_daily_bill_periods')->where('period_start', $start)->lockForUpdate()->first();
                if ($previous !== null && $previous->period_end > $end) {
                    throw new InvalidArgumentException('截止日期早于已导入范围，未替换现有账单。');
                }
                $db->table('jd_daily_bill_periods')->updateOrInsert(['period_start' => $start], $state);
            });
            return $state;
        } catch (Throwable $e) {
            $db->table('jd_daily_bill_rows')->where('generation', $generation)->delete();
            throw $e;
        } finally {
            fclose($file);
        }
    }

    private function cents(string $value): int
    {
        if (! preg_match('/^\d{1,14}(?:\.\d{1,2})?$/', trim($value))) throw new InvalidArgumentException('金额必须为精确到分的非负数。');
        [$whole, $fraction] = array_pad(explode('.', trim($value), 2), 2, '');
        return (int) $whole * 100 + (int) str_pad($fraction, 2, '0');
    }

    private function decimal(int $value): string
    {
        return intdiv($value, 100) . '.' . str_pad((string) ($value % 100), 2, '0', STR_PAD_LEFT);
    }

    private function dateTime(string $value): ?string
    {
        if (trim($value) === '') return null;
        $date = \DateTimeImmutable::createFromFormat('!Y-m-d H:i:s', $value);
        if (! $date || $date->format('Y-m-d H:i:s') !== $value) throw new InvalidArgumentException('账单时间格式无效。');
        return $value;
    }
}