// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Security.Claims;
using Amazon.Runtime;
using Microsoft.AspNetCore.Builder;
using System.Net;
using Microsoft.AspNetCore.Diagnostics;
using Microsoft.AspNetCore.Http;
using System.Text.Json;
using AWS.Deploy.CLI.ServerMode.Models;
using AWS.Deploy.Common;

namespace AWS.Deploy.CLI.ServerMode
{
    public static class ExtensionMethods
    {
        /// <summary>
        /// Create an AWSCredentials object from the key information set as claims on the current request's ClaimsPrincipal.
        /// </summary>
        /// <param name="user"></param>
        public static AWSCredentials? ToAWSCredentials(this ClaimsPrincipal user)
        {
            var awsAccessKeyId = user.Claims.FirstOrDefault(x => string.Equals(x.Type, AwsCredentialsAuthenticationHandler.ClaimAwsAccessKeyId))?.Value;
            var awsSecretKey = user.Claims.FirstOrDefault(x => string.Equals(x.Type, AwsCredentialsAuthenticationHandler.ClaimAwsSecretKey))?.Value;
            var awsSessionToken = user.Claims.FirstOrDefault(x => string.Equals(x.Type, AwsCredentialsAuthenticationHandler.ClaimAwsSessionToken))?.Value;

            if(string.IsNullOrEmpty(awsAccessKeyId) || string.IsNullOrEmpty(awsSecretKey))
            {
                return null;
            }

            if(!string.IsNullOrEmpty(awsSessionToken))
            {
                return new SessionAWSCredentials(awsAccessKeyId, awsSecretKey, awsSessionToken);
            }

            return new BasicAWSCredentials(awsAccessKeyId, awsSecretKey);
        }

        public static void ConfigureExceptionHandler(this IApplicationBuilder app)
        {
            app.UseExceptionHandler(error =>
            {
                error.Run(async context =>
                {
                    context.Response.StatusCode = (int) HttpStatusCode.InternalServerError;
                    context.Response.ContentType = "application/json";
                    var contextFeature = context.Features.Get<IExceptionHandlerFeature>();
                    if (contextFeature != null)
                    {
                        var exceptionString = "";
                        if (contextFeature.Error is DeployToolException deployToolException)
                        {
                            exceptionString = JsonSerializer.Serialize(
                                new DeployToolExceptionSummary(
                                    deployToolException.ErrorCode.ToString(),
                                    deployToolException.Message,
                                    deployToolException.ProcessExitCode));
                        }
                        else
                        {
                            exceptionString = JsonSerializer.Serialize(
                                new DeployToolExceptionSummary(
                                    DeployToolErrorCode.UnexpectedError.ToString(),
                                    contextFeature.Error?.Message ?? string.Empty));
                        }
                        await context.Response.WriteAsync(exceptionString);
                    }
                });
            });
        }
    }
}