import * as cdk from "aws-cdk-lib";
import * as cognito from "aws-cdk-lib/aws-cognito";
import { Construct } from "constructs";
import { AppConfig } from "./utils/config-manager";

export interface CognitoStackProps extends cdk.NestedStackProps {
  config: AppConfig;
  callbackUrls?: string[];
}

export class CognitoStack extends cdk.NestedStack {
  public userPoolId: string;
  public userPoolClientId: string;
  public userPoolDomain: cognito.UserPoolDomain;

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

    this.createCognitoUserPool(props.config, props.callbackUrls);
  }

  private createCognitoUserPool(
    config: AppConfig,
    callbackUrls?: string[],
  ): void {
    // Use provided callback URLs or defaults
    const defaultCallbackUrls = [
      "http://localhost:3000",
      "https://localhost:3000",
    ];
    const finalCallbackUrls = callbackUrls || defaultCallbackUrls;

    const userPool = new cognito.UserPool(this, "UserPool", {
      userPoolName: `${config.stack_name_base}-user-pool`,
      selfSignUpEnabled: false,
      signInAliases: {
        email: true,
      },
      autoVerify: {
        email: true,
      },
      standardAttributes: {
        email: {
          required: true,
          mutable: false,
        },
      },
      passwordPolicy: {
        minLength: 8,
        requireLowercase: true,
        requireUppercase: true,
        requireDigits: true,
        requireSymbols: true,
      },
      accountRecovery: cognito.AccountRecovery.EMAIL_ONLY,
      removalPolicy: cdk.RemovalPolicy.DESTROY,
      userInvitation: {
        emailSubject: `Welcome to ${config.stack_name_base}!`,
        emailBody: `<p>Hello {username},</p>
<p>Welcome to ${config.stack_name_base}! Your username is <strong>{username}</strong> and your temporary password is: <strong>{####}</strong></p>
<p>Please use this temporary password to log in and set your permanent password.</p>
<p>The CloudFront URL to your application is stored as an output in the "${config.stack_name_base}" stack, and will be printed to your terminal once the deployment process completes.</p>
<p>Thanks,</p>
<p>Fullstack AgentCore Solution Template Team</p>`,
      },
    });

    const userPoolClient = new cognito.UserPoolClient(this, "UserPoolClient", {
      userPool: userPool,
      userPoolClientName: `${config.stack_name_base}-client`,
      generateSecret: false,
      authFlows: {
        userPassword: true,
        userSrp: true,
      },
      oAuth: {
        flows: {
          authorizationCodeGrant: true,
        },
        scopes: [
          cognito.OAuthScope.OPENID,
          cognito.OAuthScope.EMAIL,
          cognito.OAuthScope.PROFILE,
        ],
        // Support both localhost development and production URLs
        callbackUrls: finalCallbackUrls,
        logoutUrls: finalCallbackUrls,
      },
      preventUserExistenceErrors: true,
    });

    this.userPoolDomain = new cognito.UserPoolDomain(this, "UserPoolDomain", {
      userPool: userPool,
      cognitoDomain: {
        domainPrefix: `${config.stack_name_base.toLowerCase()}-${cdk.Aws.ACCOUNT_ID}-${
          cdk.Aws.REGION
        }`,
      },
      // Enable the newer managed login UI (v2) with the branding designer. Comment or remove this
      // if you'd like to use the old classic UI.
      managedLoginVersion: cognito.ManagedLoginVersion.NEWER_MANAGED_LOGIN,
    });

    // Create managed login branding with Cognito's default styles
    // This is required for the v2 managed login to display properly
    const managedLoginBranding = new cognito.CfnManagedLoginBranding(
      this,
      "ManagedLoginBranding",
      {
        userPoolId: userPool.userPoolId,
        clientId: userPoolClient.userPoolClientId,
        useCognitoProvidedValues: true,
      },
    );

    managedLoginBranding.node.addDependency(this.userPoolDomain);

    // Store the IDs for export
    this.userPoolId = userPool.userPoolId;
    this.userPoolClientId = userPoolClient.userPoolClientId;

    // Create admin user if email is provided in config
    if (config.admin_user_email) {
      new cognito.CfnUserPoolUser(this, "AdminUser", {
        userPoolId: userPool.userPoolId,
        username: config.admin_user_email,
        userAttributes: [
          {
            name: "email",
            value: config.admin_user_email,
          },
        ],
        desiredDeliveryMediums: ["EMAIL"],
      });

      // Output admin user creation status
      new cdk.CfnOutput(this, "AdminUserCreated", {
        description: "Admin user created and credentials emailed",
        value: `Admin user created: ${config.admin_user_email}`,
      });
    }
  }
}