import * as cdk from "aws-cdk-lib";
import * as identitystore from "aws-cdk-lib/aws-identitystore";
import * as sso from "aws-cdk-lib/aws-sso";
import { Construct } from "constructs";

const IDENTITY_CENTER_INSTANCE_ARN =
  "arn:aws:sso:::instance/ssoins-722321f42ca610e4";
const IDENTITY_STORE_ID = "d-9067ec8e26";
const VIEW_ONLY_POLICY = "arn:aws:iam::aws:policy/job-function/ViewOnlyAccess";

export interface ViewAccessStackProps extends cdk.StackProps {
  managementAccountId: string;
  securityAccountId: string;
  externalDevAccountId: string;
  devAccountId: string;
  prodAccountId: string;
}

/**
 * Identity Center group and permission set for view-only access across
 * every organization account.
 *
 * ViewOnlyAccess lists and describes resources. It does not read S3
 * objects, secret values, DynamoDB items, or log contents. There is no
 * inline policy and no sts:AssumeRole on OrganizationAccountAccessRole.
 *
 * Group membership is outside this stack.
 */
export class ViewAccessStack extends cdk.Stack {
  constructor(scope: Construct, id: string, props: ViewAccessStackProps) {
    super(scope, id, props);

    const group = new identitystore.CfnGroup(this, "ViewGroup", {
      identityStoreId: IDENTITY_STORE_ID,
      displayName: "view",
      description:
        "View-only across all organization accounts. No data-plane reads.",
    });

    const permissionSet = new sso.CfnPermissionSet(this, "ViewPermissionSet", {
      instanceArn: IDENTITY_CENTER_INSTANCE_ARN,
      name: "View",
      description:
        "ViewOnlyAccess in every organization account. No assume-role.",
      sessionDuration: "PT8H",
      managedPolicies: [VIEW_ONLY_POLICY],
    });

    this.assignment(
      "ViewManagementAssignment",
      permissionSet,
      group,
      props.managementAccountId,
    );
    this.assignment(
      "ViewSecurityAssignment",
      permissionSet,
      group,
      props.securityAccountId,
    );
    this.assignment(
      "ViewExternalDevAssignment",
      permissionSet,
      group,
      props.externalDevAccountId,
    );
    this.assignment(
      "ViewDevAssignment",
      permissionSet,
      group,
      props.devAccountId,
    );
    this.assignment(
      "ViewProdAssignment",
      permissionSet,
      group,
      props.prodAccountId,
    );
  }

  private assignment(
    id: string,
    permissionSet: sso.CfnPermissionSet,
    group: identitystore.CfnGroup,
    targetId: string,
  ): void {
    new sso.CfnAssignment(this, id, {
      instanceArn: IDENTITY_CENTER_INSTANCE_ARN,
      permissionSetArn: permissionSet.attrPermissionSetArn,
      principalId: group.attrGroupId,
      principalType: "GROUP",
      targetId,
      targetType: "AWS_ACCOUNT",
    });
  }
}