<?php

namespace Modules\EcommerceFinance\Services;

use Carbon\CarbonImmutable;
use Illuminate\Database\ConnectionInterface;
use Illuminate\Database\DatabaseManager;
use Illuminate\Validation\ValidationException;

class FinanceLedgerFlowEditor
{
    private readonly ConnectionInterface $connection;

    public function __construct(
        DatabaseManager $databases,
        private readonly FinanceLedgerCalculator $calculator,
    ) {
        $this->connection = $databases->connection(
            (string) config('upstream_mirrors.connection', 'business_mirror'),
        );
    }

    /**
     * @param array<string,mixed> $data
     * @return array<string,mixed>
     */
    public function update(array $data): array
    {
        $date = $this->date($data['flow_date'] ?? null);
        $accountShort = $this->text($data['account_short'] ?? '');
        $openingCents = $this->cents($data['opening_balance'] ?? 0);
        $inflowCents = $this->cents($data['inflow'] ?? 0);
        $outflowCents = $this->cents($data['outflow'] ?? 0);
        $closingCents = $this->cents($data['closing_balance'] ?? 0);
        $opening = $openingCents / 100;
        $inflow = $inflowCents / 100;
        $outflow = $outflowCents / 100;
        $closing = $closingCents / 100;
        $remark = $this->nullableText($data['remark'] ?? null);

        if ($openingCents + $inflowCents - $outflowCents !== $closingCents) {
            throw ValidationException::withMessages([
                'closing_balance' => '期末余额必须等于期初余额 + 当日入账 - 当日出账。',
            ]);
        }

        $this->connection->transaction(function () use (
            $date,
            $accountShort,
            $opening,
            $inflow,
            $outflow,
            $closing,
            $remark,
        ): void {
            $account = $this->connection->table('fin_accounts')
                ->where('account_short', $accountShort)
                ->lockForUpdate()
                ->first();
            if ($account === null) {
                throw ValidationException::withMessages([
                    'account_short' => '账户简称不存在，请从账户总表中选择。',
                ]);
            }

            $before = $this->existingFlow($date, $accountShort);
            $values = [
                'opening_balance' => $opening,
                'inflow' => $inflow,
                'outflow' => $outflow,
                'closing_balance' => $closing,
                'remark' => $remark,
                'updated_by' => (string) (user()?->name ?? ''),
                'updated_at' => now(),
            ];
            $existing = $this->connection->table('fin_daily_flow_overrides')
                ->where('flow_date', $date)
                ->where('account_short', $accountShort)
                ->first();
            if ($existing === null) {
                $this->connection->table('fin_daily_flow_overrides')->insert($values + [
                    'flow_date' => $date,
                    'account_short' => $accountShort,
                    'created_at' => now(),
                ]);
            } else {
                $this->connection->table('fin_daily_flow_overrides')
                    ->where('id', $existing->id)
                    ->update($values);
            }

            $this->connection->table('fin_ledger_edit_events')->insert([
                'entity_type' => 'daily_flow',
                'entity_key' => $date . '|' . $accountShort,
                'changes' => json_encode([
                    'before' => $before,
                    'after' => [
                        'flow_date' => $date,
                        'account_short' => $accountShort,
                        'opening_balance' => $opening,
                        'inflow' => $inflow,
                        'outflow' => $outflow,
                        'closing_balance' => $closing,
                        'remark' => $remark,
                    ],
                ], JSON_UNESCAPED_UNICODE | JSON_THROW_ON_ERROR),
                'user_id' => user()?->id,
                'user_name' => (string) (user()?->name ?? ''),
                'created_at' => now(),
            ]);

            $this->calculator->recalculate();
        });

        return $this->existingFlow($date, $accountShort) ?? [];
    }

    /**
     * @return array<string,mixed>|null
     */
    public function reset(string $flowDate, string $accountShort): ?array
    {
        $date = $this->date($flowDate);
        $accountShort = $this->text($accountShort);

        $this->connection->transaction(function () use ($date, $accountShort): void {
            $before = $this->existingFlow($date, $accountShort);
            $deleted = $this->connection->table('fin_daily_flow_overrides')
                ->where('flow_date', $date)
                ->where('account_short', $accountShort)
                ->delete();
            if ($deleted > 0) {
                $this->connection->table('fin_ledger_edit_events')->insert([
                    'entity_type' => 'daily_flow_reset',
                    'entity_key' => $date . '|' . $accountShort,
                    'changes' => json_encode([
                        'before' => $before,
                        'after' => null,
                    ], JSON_UNESCAPED_UNICODE | JSON_THROW_ON_ERROR),
                    'user_id' => user()?->id,
                    'user_name' => (string) (user()?->name ?? ''),
                    'created_at' => now(),
                ]);
            }

            $this->calculator->recalculate();
        });

        return $this->existingFlow($date, $accountShort);
    }

    /** @return array<string,mixed>|null */
    public function existingFlow(string $date, string $accountShort): ?array
    {
        $row = $this->connection->table('fin_daily_flows')
            ->whereDate('flow_date', $date)
            ->where('account_short', $accountShort)
            ->first();
        if ($row === null) {
            return null;
        }

        return [
            'id' => (int) $row->id,
            'flow_date' => substr((string) $row->flow_date, 0, 10),
            'company_name' => $row->company_name,
            'account_short' => $row->account_short,
            'opening_balance' => round((float) $row->opening_balance, 2),
            'inflow' => round((float) $row->inflow, 2),
            'outflow' => round((float) $row->outflow, 2),
            'closing_balance' => round((float) $row->closing_balance, 2),
            'remark' => $row->remark,
            'manual_override' => (bool) ($row->manual_override ?? false),
            'updated_by' => $row->updated_by ?? null,
        ];
    }

    private function date(mixed $value): string
    {
        $text = trim((string) $value);
        $date = CarbonImmutable::createFromFormat('!Y-m-d', $text);
        if (! $date instanceof CarbonImmutable || $date->format('Y-m-d') !== $text) {
            throw ValidationException::withMessages([
                'flow_date' => '流水日期必须使用 YYYY-MM-DD 格式。',
            ]);
        }

        return $text;
    }

    private function cents(mixed $value): int
    {
        return (int) round((float) $value * 100);
    }

    private function text(mixed $value): string
    {
        return preg_replace('/\s+/u', ' ', trim((string) $value)) ?? trim((string) $value);
    }

    private function nullableText(mixed $value): ?string
    {
        $text = $this->text($value);

        return $text !== '' ? $text : null;
    }
}