using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Tango.Console;
using Tango.Console.Network;
using Tango.Core;
using Tango.Core.DI;
using Tango.Integration.ExternalBridge;
using Tango.PPC.Common.ExternalBridge;
using Tango.Transport;

namespace Tango.PPC.Common.Console
{
    /// <summary>
    /// Represents the <see cref="IConsoleEngineService"/> default implementation 
    /// which listens to incoming console request by registering as a external bridge request handler.
    /// </summary>
    /// <seealso cref="Tango.PPC.Common.Console.IConsoleEngineService" />
    /// <seealso cref="Tango.Integration.ExternalBridge.IExternalBridgeRequestHandler" />
    [TangoCreateWhenRegistered]
    public class DefaultConsoleEngineService : ExtendedObject, IConsoleEngineService, IExternalBridgeRequestHandler
    {
        /// <summary>
        /// Gets or sets a value indicating whether this <see cref="IConsoleEngineService" /> is enabled.
        /// </summary>
        public bool Enabled { get; set; } = true;

        /// <summary>
        /// Initializes a new instance of the <see cref="DefaultConsoleEngineService"/> class.
        /// </summary>
        /// <param name="externalBridge">The external bridge service instance.</param>
        public DefaultConsoleEngineService(IPPCExternalBridgeService externalBridge)
        {
            externalBridge.RegisterRequestHandler(this);
        }

        /// <summary>
        /// Handles <see cref="GetCurrentDirectoryRequest"/> requests.
        /// </summary>
        /// <param name="request">The request.</param>
        /// <param name="token">The token.</param>
        /// <param name="transporter">The transporter.</param>
        [ExternalBridgeRequestHandlerMethod(typeof(GetCurrentDirectoryRequest), RequestHandlerLoggingMode.LogRequestName)]
        public async Task OnGetCurrentDirectoryRequest(GetCurrentDirectoryRequest request, String token, ITransporter transporter)
        {
            this.ThrowIfDisabled();

            await transporter.SendGenericResponse(new GetCurrentDirectoryResponse()
            {
                CurrentDirectory = Environment.CurrentDirectory,
                Suggestions = ConsoleExecutionEngine.GetSuggestions(Environment.CurrentDirectory)
            }, token);
        }

        /// <summary>
        /// Handles <see cref="ConsoleCommandRequest"/> requests.
        /// </summary>
        /// <param name="request">The request.</param>
        /// <param name="token">The token.</param>
        /// <param name="transporter">The transporter.</param>
        [ExternalBridgeRequestHandlerMethod(typeof(ConsoleCommandRequest), RequestHandlerLoggingMode.LogRequestNameAndContent)]
        public async Task OnConsoleCommandRequest(ConsoleCommandRequest request, String token, ITransporter transporter)
        {
            this.ThrowIfDisabled();

            LogManager.Log($"{nameof(ConsoleCommandRequest)} received with command '{request.Command}'. Executing...");

            ConsoleExecutionEngine engine = new ConsoleExecutionEngine();
            var result = await engine.Execute(request);

            LogManager.Log("Console command executed successfully.");

            await transporter.SendGenericResponse<ConsoleCommandResponse>(new ConsoleCommandResponse()
            {
                Output = result.Output,
                Suggestions = result.Suggestions,
                WorkingFolder = result.WorkingFolder
            }, token);
        }

        /// <summary>
        /// Called when any of the external bridge clients (receivers) has disconnected.
        /// </summary>
        /// <param name="receiver">The receiver.</param>
        public void OnReceiverDisconnected(ExternalBridgeReceiver receiver)
        {
            //Do nothing.
        }
    }
}