// ------------------------------------------------------------------------
// Copyright 2021 The Dapr Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//     http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ------------------------------------------------------------------------

namespace ControllerSample.Controllers
{
    using System;
    using System.Threading.Tasks;
    using Dapr;
    using Dapr.Client;
    using Microsoft.AspNetCore.Mvc;
    using Microsoft.Extensions.Logging;

    /// <summary>
    /// Sample showing Dapr integration with controller.
    /// </summary>
    [ApiController]
    public class SampleController : ControllerBase
    {
        /// <summary>
        /// SampleController Constructor with logger injection
        /// </summary>
        /// <param name="logger"></param>
        public SampleController(ILogger<SampleController> logger)
        {
            this.logger = logger;
        }

        /// <summary>
        /// State store name.
        /// </summary>
        public const string StoreName = "statestore";
        private readonly ILogger<SampleController> logger;

        /// <summary>
        /// Gets the account information as specified by the id.
        /// </summary>
        /// <param name="account">Account information for the id from Dapr state store.</param>
        /// <returns>Account information.</returns>
        [HttpGet("{account}")]
        public ActionResult<Account> Get([FromState(StoreName)] StateEntry<Account> account)
        {
            if (account.Value is null)
            {
                return this.NotFound();
            }

            return account.Value;
        }

        /// <summary>
        /// Method for depositing to account as specified in transaction.
        /// </summary>
        /// <param name="transaction">Transaction info.</param>
        /// <param name="daprClient">State client to interact with Dapr runtime.</param>
        /// <returns>A <see cref="Task{TResult}"/> representing the result of the asynchronous operation.</returns>
        ///  "pubsub", the first parameter into the Topic attribute, is name of the default pub/sub configured by the Dapr CLI.
        [Topic("pubsub", "deposit")]
        [HttpPost("deposit")]
        public async Task<ActionResult<Account>> Deposit(Transaction transaction, [FromServices] DaprClient daprClient)
        {
            logger.LogDebug("Enter deposit");
            var state = await daprClient.GetStateEntryAsync<Account>(StoreName, transaction.Id);
            state.Value ??= new Account() { Id = transaction.Id, };
            state.Value.Balance += transaction.Amount;
            await state.SaveAsync();
            return state.Value;
        }

        /// <summary>
        /// Method for withdrawing from account as specified in transaction.
        /// </summary>
        /// <param name="transaction">Transaction info.</param>
        /// <param name="daprClient">State client to interact with Dapr runtime.</param>
        /// <returns>A <see cref="Task{TResult}"/> representing the result of the asynchronous operation.</returns>
        ///  "pubsub", the first parameter into the Topic attribute, is name of the default pub/sub configured by the Dapr CLI.
        [Topic("pubsub", "withdraw")]
        [HttpPost("withdraw")]
        public async Task<ActionResult<Account>> Withdraw(Transaction transaction, [FromServices] DaprClient daprClient)
        {
            logger.LogDebug("Enter withdraw");
            var state = await daprClient.GetStateEntryAsync<Account>(StoreName, transaction.Id);

            if (state.Value == null)
            {
                return this.NotFound();
            }

            state.Value.Balance -= transaction.Amount;
            await state.SaveAsync();
            return state.Value;
        }

        /// <summary>
        /// Method for withdrawing from account as specified in transaction.
        /// </summary>
        /// <param name="transaction">Transaction info.</param>
        /// <param name="daprClient">State client to interact with Dapr runtime.</param>
        /// <returns>A <see cref="Task{TResult}"/> representing the result of the asynchronous operation.</returns>
        ///  "pubsub", the first parameter into the Topic attribute, is name of the default pub/sub configured by the Dapr CLI.
        [Topic("pubsub", "withdraw", "event.type ==\"withdraw.v2\"", 1)]
        [HttpPost("withdraw.v2")]
        public async Task<ActionResult<Account>> WithdrawV2(TransactionV2 transaction, [FromServices] DaprClient daprClient)
        {
            logger.LogDebug("Enter withdraw.v2");
            if (transaction.Channel == "mobile" && transaction.Amount > 10000)
            {
                return this.Unauthorized("mobile transactions for large amounts are not permitted.");
            }

            var state = await daprClient.GetStateEntryAsync<Account>(StoreName, transaction.Id);

            if (state.Value == null)
            {
                return this.NotFound();
            }

            state.Value.Balance -= transaction.Amount;
            await state.SaveAsync();
            return state.Value;
        }

        /// <summary>
        /// Method for returning a BadRequest result which will cause Dapr sidecar to throw an RpcException
        [HttpPost("throwException")]
        public async Task<ActionResult<Account>> ThrowException(Transaction transaction, [FromServices] DaprClient daprClient)
        {
            Console.WriteLine("Enter ThrowException");
            var task = Task.Delay(10);
            await task;
            return BadRequest(new { statusCode = 400, message = "bad request" });
        }

        /// <summary>
        /// <para>
        /// Method which uses <see cref="CustomTopicAttribute" /> for binding this endpoint to a subscription.
        /// </para>
        /// <para>
        /// This endpoint will be bound to a subscription where the topic name is the value of the environment variable 'CUSTOM_TOPIC'
        /// and the pubsub name is the value of the environment variable 'CUSTOM_PUBSUB'.
        /// </para>
        /// </summary>
        [CustomTopic("%CUSTOM_PUBSUB%", "%CUSTOM_TOPIC%")]
        [HttpPost("exampleCustomTopic")]
        public ActionResult<Account> ExampleCustomTopic(Transaction transaction)
        {
            return Ok();
        }
    }
}