import os
import pathlib

from aws_cdk import aws_events, aws_events_targets, aws_lambda, aws_lambda_event_sources, aws_sqs
from constructs import Construct


class ScheduledMessages(Construct):
    def __init__(self, scope: Construct, construct_id: str, **kwargs) -> None:
        super().__init__(scope, construct_id)

        schedule_rule = aws_events.Rule(
            self,
            "Schedule",
            schedule=aws_events.Schedule.cron(minute="0", hour="12", month="*", week_day="*", year="*"),
        )
        queue = aws_sqs.Queue(self, "Queue")

        self.__create_dispatcher_lambda(trigger_rule=schedule_rule, send_queue=queue)

        self.__create_worker_lambda(consume_queue=queue)

    def __create_dispatcher_lambda(self, trigger_rule: aws_events.Rule, send_queue: aws_sqs.Queue):
        """
        ルールで起動して、SQSにアイテムを投げるLambdaを作成する
        """
        dispatcher_lambda = aws_lambda.Function(
            self,
            "DispatcherLambda",
            environment={"SQS_NAME": send_queue.queue_name},
            **self.__build_lambda_param("dispatcher.handler"),
        )
        send_queue.grant_send_messages(dispatcher_lambda)
        trigger_rule.add_target(aws_events_targets.LambdaFunction(dispatcher_lambda))

    def __create_worker_lambda(self, consume_queue: aws_sqs.Queue):
        """
        SQSをトリガーにしてメッセージを送信する想定のLambdaを作成する
        """
        powertools_layer = aws_lambda.LayerVersion.from_layer_version_arn(
            self,
            "lambda-powertools-layer",
            f"arn:aws:lambda:{os.getenv('CDK_DEFAULT_REGION')}:017000801446:layer:AWSLambdaPowertoolsPython:3",
        )
        worker_lambda = aws_lambda.Function(
            self, "WorkerLambda", layers=[powertools_layer], **self.__build_lambda_param("worker.handler")
        )
        worker_lambda.add_event_source(aws_lambda_event_sources.SqsEventSource(consume_queue))
        consume_queue.grant_consume_messages(worker_lambda)

    def __build_lambda_param(self, handler: str):
        """
        Lambdaの共有な設定
        """
        return dict(
            code=aws_lambda.Code.from_asset(str(pathlib.Path(__file__).resolve().parent.joinpath("runtime"))),
            runtime=aws_lambda.Runtime.PYTHON_3_9,
            handler=handler,
        )

import json
import os
from dataclasses import asdict, dataclass

import boto3

sqs = boto3.resource("sqs")
queue = sqs.get_queue_by_name(QueueName=os.getenv("SQS_NAME"))

MAX_NUMBER_OF_ENTRIES = 10  # １回のキューに送信できる最大数
NUMBER_OF_SAMPLE_ITEMS = 20  # 動作確認でキューにプッシュするアイテムの数


def handler(event, context):
    for entries in get_entries():
        queue.send_messages(Entries=entries)


def get_entries():
    """
    普通のユースケースだとDBから送信対象を取ってくる感じだけれども、
    ここでは適当なデータを作るだけ
    """

    @dataclass
    class SampleItem:
        """Queueに送信するサンプルデータ"""

        user_id: int
        message: str

        def convert_entry(self):
            """`send_messages`のエンティティのフォーマットに変形する"""
            return {"Id": f"{self.user_id}", "MessageBody": json.dumps(asdict(self))}

    items_to_send = [SampleItem(i, f"メッセージ_{i}") for i in range(NUMBER_OF_SAMPLE_ITEMS)]

    entries = []
    for item in items_to_send:
        entries.append(item.convert_entry())
        if len(entries) == MAX_NUMBER_OF_ENTRIES:
            yield entries
            entries.clear()

Entries=[
    {
        'Id': '1',
        'MessageBody': 'world'
    },
    {
        'Id': '2',
        'MessageBody': 'boto3',
        'MessageAttributes': {
            'Author': {
                'StringValue': 'Daniel',
                'DataType': 'String'
            }
        }
    }
]

import json

from aws_lambda_powertools.utilities.batch import sqs_batch_processor


def record_handler(record):
    print(f"メッセージを送るよ! :{json.dumps(record['body'])}")
    return


@sqs_batch_processor(record_handler=record_handler)
def handler(event, context):
    return