import * as cdk from 'aws-cdk-lib';
import { Construct } from 'constructs';
import * as lambda from 'aws-cdk-lib/aws-lambda';
import * as lambdaNodejs from 'aws-cdk-lib/aws-lambda-nodejs';
import * as s3 from 'aws-cdk-lib/aws-s3';
import * as dynamodb from 'aws-cdk-lib/aws-dynamodb';
import * as events from 'aws-cdk-lib/aws-events';
import * as targets from 'aws-cdk-lib/aws-events-targets';
import * as iam from 'aws-cdk-lib/aws-iam';
import * as path from 'path';

export interface WorkorderSyncProps {
  region: string;
  kbDocsBucket: s3.Bucket;
  knowledgeBaseId: string;
  dataSourceId: string;
}

export class WorkorderSyncConstruct extends Construct {
  public readonly syncLambda: lambdaNodejs.NodejsFunction;

  constructor(scope: Construct, id: string, props: WorkorderSyncProps) {
    super(scope, id);

    // Import existing DynamoDB tables by name (owned by workorder-ingest stack)
    const workOrdersTable = dynamodb.Table.fromTableName(
      this, 'WorkOrdersTable', 'WorkOrders',
    );
    const commentsTable = dynamodb.Table.fromTableName(
      this, 'WorkOrderCommentsTable', 'WorkOrderComments',
    );

    // Lambda — scans DynamoDB work orders + comments, uploads markdown to S3, triggers KB ingestion
    this.syncLambda = new lambdaNodejs.NodejsFunction(this, 'SyncLambda', {
      functionName: 'seahaven-workorder-sync',
      entry: path.join(__dirname, '../../lambda/workorder-sync/index.ts'),
      runtime: lambda.Runtime.NODEJS_22_X,
      memorySize: 512,
      timeout: cdk.Duration.minutes(5),
      environment: {
        WORK_ORDERS_TABLE: workOrdersTable.tableName,
        COMMENTS_TABLE: commentsTable.tableName,
        KB_BUCKET_NAME: props.kbDocsBucket.bucketName,
        KNOWLEDGE_BASE_ID: props.knowledgeBaseId,
        DATA_SOURCE_ID: props.dataSourceId,
        REGION: props.region,
      },
    });

    // Grant read access to both DynamoDB tables
    workOrdersTable.grantReadData(this.syncLambda);
    commentsTable.grantReadData(this.syncLambda);

    // Grant read/write to the KB docs bucket (read to list+delete old, write new)
    props.kbDocsBucket.grantReadWrite(this.syncLambda);

    // Allow Lambda to start a Bedrock KB ingestion job
    this.syncLambda.addToRolePolicy(
      new iam.PolicyStatement({
        actions: ['bedrock:StartIngestionJob'],
        resources: [
          `arn:aws:bedrock:${props.region}:*:knowledge-base/${props.knowledgeBaseId}`,
        ],
      }),
    );

    // EventBridge rule — fires daily at 02:00 UTC
    const dailyRule = new events.Rule(this, 'DailySyncRule', {
      ruleName: 'seahaven-workorder-daily-sync',
      description: 'Daily Work Orders → KB sync at 02:00 UTC',
      schedule: events.Schedule.cron({ minute: '0', hour: '2' }),
    });

    dailyRule.addTarget(new targets.LambdaFunction(this.syncLambda));
  }
}