package main

import (
    "fmt"
    "log"
    "os"

    "github.com/aws/aws-sdk-go/aws"
    "github.com/aws/aws-sdk-go/aws/awserr"
    "github.com/aws/aws-lambda-go/lambda"
    "github.com/aws/aws-sdk-go/aws/session"
    cidp "github.com/aws/aws-sdk-go/service/cognitoidentityprovider"
    cidpif "github.com/aws/aws-sdk-go/service/cognitoidentityprovider/cognitoidentityprovideriface"
    util "github.com/sean/repo/internal/util"
)

type application struct {
    config configuration
}

type configuration struct {
    ClientPoolID string
    UserPoolID   string
    idp          cidpif.CognitoIdentityProviderAPI
}

func (app application) getUserPoolClientSecret() (string, error) {
    input := &cidp.DescribeUserPoolClientInput{
        UserPoolId: aws.String(app.config.UserPoolID),
        ClientId:   aws.String(app.config.ClientPoolID),
    }

    resp, err := app.config.idp.DescribeUserPoolClient(input)
    if err != nil {
        if aerr, ok := err.(awserr.Error); ok {
            log.Printf("[ERROR] %v", aerr.Error())
        } else {
            log.Printf("[ERROR] %v", err.Error())
        }
        return "", err
    }
    log.Println("[INFO] Obtained user pool client secret successfully")
    return *resp.UserPoolClient.ClientSecret, nil
}

func main() {
    config := configuration{
        ClientPoolID: os.Getenv("CLIENT_POOL_ID"),
        UserPoolID:   os.Getenv("USER_POOL_ID"),
        idp:          cidp.New(session.Must(session.NewSession())),
    }

    app := application{config: config}

    lambda.Start(app.handler) // handler() calls app.getUserPoolClientSecret
}