using System;
using System.Threading.Tasks;
using TelegramBotBase.Base;

namespace TelegramBotBase.Controls.Inline
{
    /// <summary>
    /// A simple control for show and managing progress.
    /// </summary>
    public class ProgressBar : ControlBase
    {
        public enum EProgressStyle
        {
            standard = 0,
            squares = 1,
            circles = 2,
            lines = 3,
            squaredLines = 4,
            custom = 10
        }

        public EProgressStyle ProgressStyle
        {
            get => _mEStyle;
            set
            {
                _mEStyle = value;
                LoadStyle();
            }
        }

        private EProgressStyle _mEStyle = EProgressStyle.standard;


        public int Value
        {
            get => _mIValue;
            set
            {
                if (value > Max)
                {
                    return;
                }

                if (_mIValue != value)
                {
                    RenderNecessary = true;
                }
                _mIValue = value;
            }
        }

        private int _mIValue;

        public int Max
        {
            get => _mIMax;
            set
            {
                if (_mIMax != value)
                {
                    RenderNecessary = true;
                }
                _mIMax = value;
            }
        }

        private int _mIMax = 100;

        public int? MessageId { get; set; }

        private bool RenderNecessary { get; set; }

        public int Steps
        {
            get
            {
                return ProgressStyle switch
                {
                    EProgressStyle.standard => 1,
                    EProgressStyle.squares => 10,
                    EProgressStyle.circles => 10,
                    EProgressStyle.lines => 5,
                    EProgressStyle.squaredLines => 5,
                    _ => 1
                };
            }
        }

        /// <summary>
        /// Filled block (reached percentage)
        /// </summary>
        public string BlockChar
        {
            get; set;
        }

        /// <summary>
        /// Unfilled block (not reached yet)
        /// </summary>
        public string EmptyBlockChar
        {
            get; set;
        }

        /// <summary>
        /// String at the beginning of the progress bar
        /// </summary>
        public string StartChar
        {
            get; set;
        }

        /// <summary>
        /// String at the end of the progress bar
        /// </summary>
        public string EndChar
        {
            get; set;
        }

        public ProgressBar()
        {
            ProgressStyle = EProgressStyle.standard;

            Value = 0;
            Max = 100;

            RenderNecessary = true;
        }

        public ProgressBar(int value, int max, EProgressStyle style)
        {
            this.Value = value;
            this.Max = max;
            ProgressStyle = style;

            RenderNecessary = true;
        }

        public override async Task Cleanup()
        {
            if (MessageId == null || MessageId == -1)
                return;


            await Device.DeleteMessage(MessageId.Value);
        }

        public void LoadStyle()
        {
            StartChar = "";
            EndChar = "";

            switch (ProgressStyle)
            {
                case EProgressStyle.circles:

                    BlockChar = "⚫️ ";
                    EmptyBlockChar = "⚪️ ";

                    break;
                case EProgressStyle.squares:

                    BlockChar = "⬛️ ";
                    EmptyBlockChar = "⬜️ ";

                    break;
                case EProgressStyle.lines:

                    BlockChar = "█";
                    EmptyBlockChar = "▁";

                    break;
                case EProgressStyle.squaredLines:

                    BlockChar = "▇";
                    EmptyBlockChar = "—";

                    StartChar = "[";
                    EndChar = "]";

                    break;
                case EProgressStyle.standard:
                case EProgressStyle.custom:

                    BlockChar = "";
                    EmptyBlockChar = "";

                    break;
            }

        }

        public override async Task Render(MessageResult result)
        {
            if (!RenderNecessary)
            {
                return;
            }

            if (Device == null)
            {
                return;
            }

            var message = "";
            var blocks = 0;
            var maxBlocks = 0;

            switch (ProgressStyle)
            {
                case EProgressStyle.standard:

                    message = Value.ToString("0") + "%";

                    break;

                case EProgressStyle.squares:
                case EProgressStyle.circles:
                case EProgressStyle.lines:
                case EProgressStyle.squaredLines:
                case EProgressStyle.custom:

                    blocks = (int)Math.Floor((decimal)Value / Steps);

                    maxBlocks = (Max / Steps);

                    message += StartChar;

                    for (var i = 0; i < blocks; i++)
                    {
                        message += BlockChar;
                    }

                    for (var i = 0; i < (maxBlocks - blocks); i++)
                    {
                        message += EmptyBlockChar;
                    }

                    message += EndChar;

                    message += " " + Value.ToString("0") + "%";

                    break;

                default:

                    return;
            }

            if (MessageId == null)
            {
                var m = await Device.Send(message);

                MessageId = m.MessageId;
            }
            else
            {
                await Device.Edit(MessageId.Value, message);
            }

            RenderNecessary = false;
        }

    }
}