<?php

namespace Modules\EcommerceFinance\Services;

use Closure;
use Illuminate\Database\ConnectionInterface;
use Illuminate\Support\Facades\DB;

class SupplierPayableOverrideStore
{
    public function key(string $dataset, array $row): string
    {
        if (isset($row['sourceId']) && $row['sourceId'] !== '') {
            return 'id:' . (string) ($row['recordType'] ?? '') . ':' . (string) $row['sourceId'];
        }
        if (isset($row['id']) && $row['id'] !== '') {
            return 'id:' . (string) $row['id'];
        }

        $immutable = $row;
        unset($immutable['_action_key'], $immutable['_overridden']);

        return 'hash:' . hash('sha256', json_encode($immutable, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES));
    }

    /** @param array<int,array<string,mixed>> $rows */
    public function decorate(string $dataset, array $rows, int $companyId): array
    {
        if ($rows === []) {
            return [];
        }

        $keys = [];
        foreach ($rows as $row) {
            $keys[] = $this->key($dataset, $row);
        }

        $overrides = $this->connection()->table('supplier_payable_overrides')
            ->where('company_id', $companyId)
            ->where('dataset', $dataset)
            ->whereIn('record_key', $keys)
            ->get()
            ->keyBy('record_key');

        foreach ($rows as $index => &$row) {
            $key = $keys[$index];
            $row['_action_key'] = $key;
            $override = $overrides->get($key);
            if ($override) {
                $values = json_decode((string) $override->values, true) ?: [];
                $row = array_merge($row, $values);
                $row['_overridden'] = true;
            } else {
                $row['_overridden'] = false;
            }
        }
        unset($row);

        return $rows;
    }

    /** @return array{created:int,updated:int} */
    public function save(string $dataset, string $recordKey, array $values, int $companyId, ?int $userId, string $source = 'manual'): array
    {
        $connection = $this->connection();
        $existing = $connection->table('supplier_payable_overrides')
            ->where(['company_id' => $companyId, 'dataset' => $dataset, 'record_key' => $recordKey])
            ->first();
        $before = $existing ? (json_decode((string) $existing->values, true) ?: []) : null;
        $now = now();

        $connection->transaction(function () use ($connection, $existing, $dataset, $recordKey, $values, $companyId, $userId, $now, $source, $before): void {
            $connection->table('supplier_payable_overrides')->updateOrInsert(
                ['company_id' => $companyId, 'dataset' => $dataset, 'record_key' => $recordKey],
                [
                    'values' => json_encode($values, JSON_UNESCAPED_UNICODE),
                    'updated_by' => $userId,
                    'created_by' => $existing->created_by ?? $userId,
                    'created_at' => $existing->created_at ?? $now,
                    'updated_at' => $now,
                ],
            );
            $connection->table('supplier_payable_override_events')->insert([
                'company_id' => $companyId,
                'dataset' => $dataset,
                'record_key' => $recordKey,
                'source' => $source,
                'before_values' => $before === null ? null : json_encode($before, JSON_UNESCAPED_UNICODE),
                'after_values' => json_encode($values, JSON_UNESCAPED_UNICODE),
                'user_id' => $userId,
                'created_at' => $now,
            ]);
        });

        return ['created' => $existing ? 0 : 1, 'updated' => $existing ? 1 : 0];
    }

    /**
     * 批量保存（大文件导入用）：按记录键 upsert，并批量写审计事件。
     *
     * @param  array<string,array<string,mixed>>  $records  记录键 => 字段值
     * @return array{created:int,updated:int}
     */
    public function saveBatch(string $dataset, array $records, int $companyId, ?int $userId, string $source = 'import'): array
    {
        if ($records === []) {
            return ['created' => 0, 'updated' => 0];
        }

        $connection = $this->connection();
        $now = now();
        $created = 0;
        $updated = 0;

        $connection->transaction(function () use ($connection, $dataset, $records, $companyId, $userId, $source, $now, &$created, &$updated): void {
            $existing = [];
            foreach (array_chunk(array_keys($records), 1000) as $keys) {
                foreach ($connection->table('supplier_payable_overrides')
                    ->where('company_id', $companyId)
                    ->where('dataset', $dataset)
                    ->whereIn('record_key', $keys)
                    ->get() as $row) {
                    $existing[(string) $row->record_key] = $row;
                }
            }

            $upserts = [];
            $events = [];
            foreach ($records as $key => $values) {
                $before = $existing[$key] ?? null;
                $before === null ? $created++ : $updated++;
                $encoded = $this->encodeValues($values);

                $upserts[] = [
                    'company_id' => $companyId,
                    'dataset' => $dataset,
                    'record_key' => $key,
                    'values' => $encoded,
                    'created_by' => $before->created_by ?? $userId,
                    'updated_by' => $userId,
                    'created_at' => $before->created_at ?? $now,
                    'updated_at' => $now,
                ];
                $events[] = [
                    'company_id' => $companyId,
                    'dataset' => $dataset,
                    'record_key' => $key,
                    'source' => $source,
                    'before_values' => $before === null ? null : (string) $before->values,
                    'after_values' => $encoded,
                    'user_id' => $userId,
                    'created_at' => $now,
                ];
            }

            foreach (array_chunk($upserts, 500) as $chunk) {
                $connection->table('supplier_payable_overrides')->upsert(
                    $chunk,
                    ['company_id', 'dataset', 'record_key'],
                    ['values', 'updated_by', 'updated_at'],
                );
            }

            foreach (array_chunk($events, 500) as $chunk) {
                $connection->table('supplier_payable_override_events')->insert($chunk);
            }
        });

        return ['created' => $created, 'updated' => $updated];
    }

    public function transaction(Closure $callback): mixed
    {
        return $this->connection()->transaction($callback);
    }

    /**
     * 整份替换某个数据集（厂家对账单：以最新一版为准），不写逐行审计事件。
     *
     * @param  array<string,array<string,mixed>>  $records
     */
    public function replaceAll(string $dataset, array $records, int $companyId, ?int $userId): int
    {
        $connection = $this->connection();
        $now = now();
        $rows = [];
        foreach ($records as $key => $values) {
            $rows[] = [
                'company_id' => $companyId,
                'dataset' => $dataset,
                'record_key' => (string) $key,
                'values' => $this->encodeValues($values),
                'created_by' => $userId,
                'updated_by' => $userId,
                'created_at' => $now,
                'updated_at' => $now,
            ];
        }

        $connection->transaction(function () use ($connection, $dataset, $companyId, $rows): void {
            $connection->table('supplier_payable_overrides')
                ->where('company_id', $companyId)
                ->where('dataset', $dataset)
                ->delete();

            foreach (array_chunk($rows, 500) as $chunk) {
                $connection->table('supplier_payable_overrides')->insert($chunk);
            }
        });

        return count($rows);
    }

    /** @return list<string> 某个前缀下已有的数据集名 */
    public function datasetsWithPrefix(string $prefix, int $companyId): array
    {
        return $this->connection()->table('supplier_payable_overrides')
            ->where('company_id', $companyId)
            ->where('dataset', 'like', addcslashes($prefix, '%_\\') . '%')
            ->distinct()
            ->orderBy('dataset')
            ->pluck('dataset')
            ->map(static fn (mixed $value): string => (string) $value)
            ->all();
    }

    /** 值编码为 JSON；脏字节（非法 UTF-8）用替代字符，避免整批写入失败。 */
    private function encodeValues(array $values): string
    {
        return (string) json_encode($values, JSON_UNESCAPED_UNICODE | JSON_INVALID_UTF8_SUBSTITUTE);
    }

    /**
     * 列出某个数据集已经保存的全部记录（「终版」目录的独立数据就是这些行）。
     *
     * @return array<int,array<string,mixed>>
     */
    public function listRows(string $dataset, int $companyId): array
    {
        return $this->connection()->table('supplier_payable_overrides')
            ->where('company_id', $companyId)
            ->where('dataset', $dataset)
            ->orderBy('id')
            ->get()
            ->map(static function (object $record): array {
                $values = json_decode((string) $record->values, true) ?: [];
                $values['_action_key'] = (string) $record->record_key;

                return $values;
            })
            ->all();
    }

    private function connection(): ConnectionInterface
    {
        return DB::connection(config('database.supplier_payable_maintenance_connection'));
    }
}