/*
 * Copyright (c) 2017 Samsung Electronics Co., Ltd
 *
 * Licensed under the Flora License, Version 1.1 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://floralicense.org/license/
 *
 * 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.
 */

using System;
using System.Runtime.CompilerServices;
using Xamarin.Forms;

namespace LibTVRefCommonPortable.Utils
{
    /// <summary>
    /// A debugging utility class.
    /// </summary>
    public sealed class DebuggingUtils
    {
        /// <summary>
        /// A debugging API interface
        /// </summary>
        private static IDebuggingAPIs ism;

        /// <summary>
        /// An instance of DebuggingUtils
        /// </summary>
        private static readonly DebuggingUtils instance = new DebuggingUtils();

        /// <summary>
        /// A method provides instance of DebuggingUtils. </summary>
        public static DebuggingUtils Instance
        {
            get { return instance; }
        }

        /// <summary>
        /// Default implementation of IDebuggingAPIs interface .
        /// This is required for the unit testing of the Calculator application.
        /// </summary>
        private class DefaultSM : IDebuggingAPIs
        {
            /// <summary>
            /// A method displays an error log.
            /// </summary>
            /// <param name="message"> An error message.</param>
            /// <param name="file"> A file name.</param>
            /// <param name="func"> A function name.</param>
            /// <param name="line"> A line number.</param>
            public void Dbg(string message, String file, String func, Int32 line)
            {
            }

            /// <summary>
            /// A method displays a dialog with a given message.
            /// </summary>
            /// <param name="message"> A debugging message.</param>
            /// <param name="file"> A file name.</param>
            /// <param name="func"> A function name.</param>
            /// <param name="line"> A line number.</param>
            public void Err(string message, String file, String func, Int32 line)
            {
            }

            /// <summary>
            /// A method displays a debugging log.
            /// </summary>
            /// <param name="message"> A debugging message.</param>
            public void Popup(string message)
            {
            }
        }

        /// <summary>
        /// DebuggingUtils constructor which set interface instance.
        /// </summary>
        private DebuggingUtils()
        {
            ism = new DefaultSM();

            try
            {
                if (DependencyService.Get<IDebuggingAPIs>() != null)
                {
                    ism = DependencyService.Get<IDebuggingAPIs>();
                }
            }
            catch (InvalidOperationException e)
            {
                Err(e.Message);
            }
        }

        /// <summary>
        /// A method displays a debugging message
        /// </summary>
        /// <param name="message"> A list of command line arguments.</param>
        /// <param name="file"> A file name.</param>
        /// <param name="func"> A function name.</param>
        /// <param name="line"> A line number.</param>
        public static void Dbg(string message, [CallerFilePath] System.String file = "", [CallerMemberName] System.String func = "", [CallerLineNumber] System.Int32 line = 0)
        {
            ism.Dbg(message, file, func, line);
        }

        /// <summary>
        /// A method displays an error message
        /// </summary>
        /// <param name="message"> A list of command line arguments.</param>
        /// <param name="file"> A file name.</param>
        /// <param name="func"> A function name.</param>
        /// <param name="line"> A line number.</param>
        public static void Err(string message, [CallerFilePath] System.String file = "", [CallerMemberName] System.String func = "", [CallerLineNumber] System.Int32 line = 0)
        {
            ism.Err(message, file, func, line);
        }

        /// <summary>
        /// A method displays a pop up  message
        /// </summary>
        /// <param name="message"> A list of command line arguments.</param>
        public static void Popup(string message)
        {
            ism.Popup(message);
        }
    }
}