<?php

namespace Modules\EcommerceFinance\Services;

use App\Models\Auth\User;
use Illuminate\Support\Facades\DB;

/**
 * 按账户总表批量建立“供应商应付”公司名称到账户简称的映射。
 *
 * 公司只有唯一账户，或虽有多个账户但只有一个公户时自动关联；
 * 多公户、只有私人卡等歧义情况保留人工选择。
 */
class FinanceLedgerPayableMappingBulk
{
    public function preview(): array
    {
        $connection = $this->connection();
        $accountsByCompany = [];
        foreach ($connection->table('fin_accounts')->get(['company_name', 'account_short', 'account_type']) as $account) {
            $company = trim((string) $account->company_name);
            $accountShort = trim((string) $account->account_short);
            if ($company === '' || $accountShort === '') {
                continue;
            }
            $accountsByCompany[$company][$accountShort] = [
                'account_short' => $accountShort,
                'account_type' => trim((string) $account->account_type),
            ];
        }

        $rows = $connection->table('fin_account_map')
            ->where('source', 'payable')
            ->where(function ($query): void {
                $query->whereNull('account_short')->orWhere('account_short', '');
            })
            ->orderBy('source_value')
            ->get(['id', 'source_value']);

        $candidates = [];
        $ambiguous = [];
        $missing = [];
        foreach ($rows as $row) {
            $company = trim((string) $row->source_value);
            $accounts = array_values($accountsByCompany[$company] ?? []);
            if ($accounts === []) {
                $missing[] = $company;
                continue;
            }
            if (count($accounts) === 1) {
                $candidates[] = $this->candidate($row, $accounts[0]['account_short'], 'single_account');
                continue;
            }

            $publicAccounts = array_values(array_filter(
                $accounts,
                static fn (array $account): bool => $account['account_type'] === '公户',
            ));
            if (count($publicAccounts) === 1) {
                $candidates[] = $this->candidate($row, $publicAccounts[0]['account_short'], 'single_public_account');
                continue;
            }

            $ambiguous[] = [
                'company' => $company,
                'accounts' => array_values(array_map(
                    static fn (array $account): string => $account['account_short'],
                    $accounts,
                )),
            ];
        }

        return [
            'total' => $rows->count(),
            'eligible' => count($candidates),
            'ambiguous' => count($ambiguous),
            'missing' => count($missing),
            'candidates' => $candidates,
            'ambiguous_values' => $ambiguous,
            'missing_values' => $missing,
        ];
    }

    public function apply(?User $user = null): array
    {
        $preview = $this->preview();
        $connection = $this->connection();
        $userName = (string) ($user?->name ?? '');
        $userId = (int) ($user?->id ?? 0);
        $now = now();
        $mapped = 0;

        if ($preview['candidates'] !== []) {
            $connection->transaction(function () use ($connection, $preview, $userName, $userId, $now, &$mapped): void {
                foreach ($preview['candidates'] as $candidate) {
                    $updated = $connection->table('fin_account_map')
                        ->where('id', $candidate['id'])
                        ->where(function ($query): void {
                            $query->whereNull('account_short')->orWhere('account_short', '');
                        })
                        ->update([
                            'account_short' => $candidate['account_short'],
                            'updated_by' => $userName,
                            'updated_at' => $now,
                        ]);
                    if ($updated !== 1) {
                        continue;
                    }

                    $connection->table('fin_account_map_events')->insert([
                        'source' => 'payable',
                        'source_value' => $candidate['source_value'],
                        'old_account_short' => null,
                        'new_account_short' => $candidate['account_short'],
                        'user_id' => $userId,
                        'user_name' => $userName,
                        'created_at' => $now,
                    ]);
                    $mapped++;
                }
            });
        }

        if ($mapped > 0) {
            app(FinanceLedgerCalculator::class)->recalculate();
        }

        return [
            'total' => $preview['total'],
            'mapped' => $mapped,
            'ambiguous' => $preview['ambiguous'],
            'missing' => $preview['missing'],
        ];
    }

    private function candidate(object $row, string $accountShort, string $matchType): array
    {
        return [
            'id' => (int) $row->id,
            'source_value' => trim((string) $row->source_value),
            'account_short' => $accountShort,
            'match_type' => $matchType,
        ];
    }

    private function connection()
    {
        return DB::connection((string) config('upstream_mirrors.connection', 'business_mirror'));
    }
}