import { createRequire } from 'module';
const require = createRequire(import.meta.url);
const { S3Client, HeadObjectCommand } = require('@aws-sdk/client-s3');
const { CodeDeployClient, CreateDeploymentCommand } = require('@aws-sdk/client-codedeploy');

// Initialize the S3 and CodeDeploy clients
const s3Client = new S3Client({ apiVersion: '2006-03-01' });
const codedeployClient = new CodeDeployClient();

export const handler = async(event, context) => {
    console.log('Received event:');
    console.log(JSON.stringify(event, null, '  '));

    // Get the object from the event
    const bucket = event.Records[0].s3.bucket.name;
    const key = event.Records[0].s3.object.key;
    let artifact_type = key.split('.').pop();
    artifact_type = artifact_type === 'gz' ? 'tgz' : ['zip', 'tar', 'tgz'].includes(artifact_type) ? artifact_type : 'tar';

    try {
        const data = await s3Client.send(new HeadObjectCommand({
            Bucket: bucket,
            Key: key
        }));
        
        await createDeployment(data);
    } catch (err) {
        console.error('Error', 'Error getting s3 object or creating deployment: ' + err);
        return;
    }

    async function createDeployment(s3ObjectData) {
         if (!s3ObjectData.Metadata['application-name'] || !s3ObjectData.Metadata['deploymentgroup-name']) {
            throw new Error('application-name and deploymentgroup-name object metadata must be set.');
         }

        const params = {
            applicationName: s3ObjectData.Metadata['application-name'],
            deploymentGroupName: s3ObjectData.Metadata['deploymentgroup-name'],
            description: 'Lambda invoked codedeploy deployment',
            ignoreApplicationStopFailures: false,
            revision: {
                revisionType: 'S3',
                s3Location: {
                    bucket: bucket,
                    bundleType: artifact_type,
                    key: key
                }
            }
        };

        const createDeploymentCommand = new CreateDeploymentCommand(params);
        const deploymentResponse = await codedeployClient.send(createDeploymentCommand);
        console.log(deploymentResponse);
        console.log('Finished executing lambda function');
    }
};