import { Module } from '@nestjs/common';
import { CommandModule, DataService, CommandService } from '@mbc-cqrs-serverless/core';

@Module({
  imports: [
    CommandModule.register({
      tableName: 'todo',
    }),
  ],
})
export class TodoModule {}

import { Injectable } from '@nestjs/common';
import {
  CommandService,
  DataService,
  generateId,
  getUserContext,
  VERSION_FIRST,
  IInvoke,
} from '@mbc-cqrs-serverless/core';

@Injectable()
export class TodoService {
  constructor(
    private readonly commandService: CommandService,
    private readonly dataService: DataService,
  ) {}

  async create(dto: CreateTodoDto, opts: { invokeContext: IInvoke }) {
    const { tenantCode } = getUserContext(opts.invokeContext);
    const pk = `TODO#${tenantCode}`;
    const sk = `TODO#${Date.now()}`;

    const command = {
      pk,
      sk,
      id: generateId(pk, sk),
      tenantCode,
      code: sk,
      type: 'TODO',
      version: VERSION_FIRST,
      name: dto.name,
      attributes: dto.attributes,
    };

    return await this.commandService.publishAsync(command, opts);
  }

  async findOne(pk: string, sk: string) {
    return await this.dataService.getItem({ pk, sk });
  }
}

// VERSION_FIRST = 0 for new items
const command = { pk, sk, version: VERSION_FIRST, ... };
await commandService.publishAsync(command, opts);

// Updates require the current version
const updateCommand = { pk, sk, version: currentVersion, ... };
await commandService.publishPartialUpdateAsync(updateCommand, opts);

import {
  generateId,        // Generate unique ID from pk and sk
  getUserContext,    // Extract user info from Lambda context
  addSortKeyVersion, // Add version suffix to sort key
  removeSortKeyVersion, // Remove version suffix from sort key
  getTenantCode,     // Extract tenant code from partition key
} from '@mbc-cqrs-serverless/core';

import {
  VERSION_FIRST,   // Initial version (0)
  VERSION_LATEST,  // Marker for latest version (-1)
  VER_SEPARATOR,   // Version separator in sort key ('#')
} from '@mbc-cqrs-serverless/core';

import { Injectable } from '@nestjs/common';
import {
  IDataSyncHandler,
  DataSyncHandler,
  CommandModel,
} from '@mbc-cqrs-serverless/core';
import { PrismaService } from '../prisma/prisma.service';

@DataSyncHandler({ tableName: 'todo' })
@Injectable()
export class TodoDataSyncHandler implements IDataSyncHandler {
  type = 'rds';

  constructor(private readonly prisma: PrismaService) {}

  async up(cmd: CommandModel): Promise<void> {
    await this.prisma.todo.upsert({
      where: { pk_sk: { pk: cmd.pk, sk: cmd.sk } },
      create: { /* ... */ },
      update: { /* ... */ },
    });
  }

  async down(cmd: CommandModel): Promise<void> {
    // Optional: handle rollback
  }
}