import * as cdk from "aws-cdk-lib";
import * as s3 from "aws-cdk-lib/aws-s3";
import * as iam from "aws-cdk-lib/aws-iam";
import * as securityhub from "aws-cdk-lib/aws-securityhub";
import { Construct } from "constructs";
import { BedrockLoggingRegional } from "./bedrock-logging-regional";

/**
 * Regional security-baseline stack for secondary regions (INFRA-16, INFRA-91).
 *
 * The account baseline (lib/account-baseline-stack.ts) is us-east-1 only by
 * design. This stack extends a minimal detective/logging footprint into the
 * other regions where workloads or Bedrock traffic land, WITHOUT duplicating
 * the full us-east-1 stack.
 *
 * Composition is opt-in per region via props so one class serves both
 * secondary regions:
 *   - bedrockLogging  → INFRA-91 Bedrock invocation-logging destination + role
 *                       (us-west-2 + us-east-2; codifies live CLI state)
 *   - configRecorder  → INFRA-16 AWS Config recorder role + delivery bucket
 *                       (us-east-2; recorder/channel applied via CLI, see header)
 *   - securityHub     → INFRA-16 Security Hub + FSBP/CIS standards (us-east-2)
 *
 * GuardDuty and default-VPC flow logs already exist in us-east-2 (applied
 * out-of-band) and are intentionally NOT adopted here yet — importing live
 * resources of those L1 types risks a replace diff; they are tracked as a
 * follow-up so this reconciliation stays additive/non-destructive.
 */
export interface RegionalBaselineStackProps extends cdk.StackProps {
  /** INFRA-91: stand up Bedrock invocation-logging destination + delivery role. */
  readonly bedrockLogging?: boolean;
  /** INFRA-16: stand up AWS Config recorder role + delivery bucket. */
  readonly configRecorder?: boolean;
  /** INFRA-16: enable Security Hub with FSBP + CIS v3.0 standards. */
  readonly securityHub?: boolean;
}

export class RegionalBaselineStack extends cdk.Stack {
  constructor(scope: Construct, id: string, props: RegionalBaselineStackProps) {
    super(scope, id, props);

    if (props.bedrockLogging) {
      // INFRA-91 — codifies live us-west-2 / us-east-2 Bedrock logging.
      new BedrockLoggingRegional(this, "BedrockLogging");
    }

    if (props.configRecorder) {
      // INFRA-16 — AWS Config in us-east-2. Same pattern as the us-east-1
      // DetectiveControls construct: the role + delivery bucket live in IaC;
      // the recorder + delivery channel are applied via CLI post-deploy because
      // the L1 ConfigurationRecorder/DeliveryChannel pair deadlocks CFN (the
      // recorder will not reach CREATE_COMPLETE without a channel, and the
      // channel cannot be created until the recorder completes — observed in
      // us-east-1 2026-06-01). Commands are documented in the README.
      const configBucket = new s3.Bucket(this, "ConfigBucket", {
        bucketName: `seahaven-config-${this.region}-${this.account}`,
        encryption: s3.BucketEncryption.S3_MANAGED,
        blockPublicAccess: s3.BlockPublicAccess.BLOCK_ALL,
        enforceSSL: true,
        versioned: true,
        lifecycleRules: [
          {
            id: "expire-old-config",
            expiration: cdk.Duration.days(365),
            abortIncompleteMultipartUploadAfter: cdk.Duration.days(7),
          },
        ],
        removalPolicy: cdk.RemovalPolicy.RETAIN,
      });

      configBucket.addToResourcePolicy(
        new iam.PolicyStatement({
          sid: "AWSConfigBucketPermissionsCheck",
          effect: iam.Effect.ALLOW,
          principals: [new iam.ServicePrincipal("config.amazonaws.com")],
          actions: ["s3:GetBucketAcl", "s3:ListBucket"],
          resources: [configBucket.bucketArn],
          conditions: {
            StringEquals: { "aws:SourceAccount": this.account },
          },
        })
      );
      configBucket.addToResourcePolicy(
        new iam.PolicyStatement({
          sid: "AWSConfigBucketDelivery",
          effect: iam.Effect.ALLOW,
          principals: [new iam.ServicePrincipal("config.amazonaws.com")],
          actions: ["s3:PutObject"],
          resources: [
            configBucket.arnForObjects(`AWSLogs/${this.account}/Config/*`),
          ],
          conditions: {
            StringEquals: {
              "s3:x-amz-acl": "bucket-owner-full-control",
              "aws:SourceAccount": this.account,
            },
          },
        })
      );

      // Region-suffixed role name so it does not collide with the us-east-1
      // seahaven-config-recorder-role (IAM roles are global by name).
      const recorderRole = new iam.Role(this, "ConfigRecorderRole", {
        roleName: `seahaven-config-recorder-role-${this.region}`,
        assumedBy: new iam.ServicePrincipal("config.amazonaws.com"),
        managedPolicies: [
          iam.ManagedPolicy.fromAwsManagedPolicyName(
            "service-role/AWS_ConfigRole"
          ),
        ],
      });
      recorderRole.addToPolicy(
        new iam.PolicyStatement({
          sid: "ConfigDeliveryToBucket",
          effect: iam.Effect.ALLOW,
          actions: ["s3:PutObject"],
          resources: [
            configBucket.arnForObjects(`AWSLogs/${this.account}/Config/*`),
          ],
          conditions: {
            StringEquals: { "s3:x-amz-acl": "bucket-owner-full-control" },
          },
        })
      );
      recorderRole.addToPolicy(
        new iam.PolicyStatement({
          sid: "ConfigBucketAcl",
          effect: iam.Effect.ALLOW,
          actions: ["s3:GetBucketAcl"],
          resources: [configBucket.bucketArn],
        })
      );

      new cdk.CfnOutput(this, "ConfigRecorderRoleArn", {
        value: recorderRole.roleArn,
      });
      new cdk.CfnOutput(this, "ConfigBucketName", {
        value: configBucket.bucketName,
      });
    }

    if (props.securityHub) {
      // INFRA-16 — Security Hub (FSBP + CIS v3.0) in us-east-2. Mirrors the
      // us-east-1 DetectiveControls Security Hub block. Findings populate once
      // the Config recorder above is recording.
      const hub = new securityhub.CfnHub(this, "SecurityHub", {
        enableDefaultStandards: false,
        controlFindingGenerator: "SECURITY_CONTROL",
        autoEnableControls: true,
      });

      const fsbpArn = cdk.Arn.format(
        {
          service: "securityhub",
          region: this.region,
          account: "",
          resource: "standards",
          resourceName: "aws-foundational-security-best-practices/v/1.0.0",
        },
        this
      );
      const cisArn = cdk.Arn.format(
        {
          service: "securityhub",
          region: this.region,
          account: "",
          resource: "standards",
          resourceName: "cis-aws-foundations-benchmark/v/3.0.0",
        },
        this
      );

      const fsbp = new securityhub.CfnStandard(this, "StandardFSBP", {
        standardsArn: fsbpArn,
      });
      fsbp.node.addDependency(hub);

      const cis = new securityhub.CfnStandard(this, "StandardCIS", {
        standardsArn: cisArn,
      });
      cis.node.addDependency(hub);
    }

    cdk.Tags.of(this).add("Project", "account-baseline");
    cdk.Tags.of(this).add("Owner", "adam@seahavenind.com");
    cdk.Tags.of(this).add("Environment", "prod");
    cdk.Tags.of(this).add("ManagedBy", "cdk");
  }
}