using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace GeoSigma.SigmaDrawerStyle.Converter
{
    public abstract class DoubleConverter : BaseTypeConverter
    {
        protected virtual string FmtString { get; set; } = "{0}";
        public int DigitDecimal { get; set; } = -1;
        /// <summary>
        /// Initializes a new instance of the <see cref="DoubleConverter"/> class.
        /// </summary>
        public DoubleConverter()
            : base()
        {
        }
        /// <summary>
        /// Initializes a new instance of the <see cref="DoubleConverter"/> class.
        /// </summary>
        /// <param name="digitDecimal">小数位数</param>
        public DoubleConverter(int digitDecimal)
            : this()
        {
            this.DigitDecimal = digitDecimal;
            if (this.DigitDecimal >= 0)
            {
                FmtString = $"{{0:F{this.DigitDecimal}}}";
            }
        }

        public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
        {
            if (sourceType == typeof(string))
            {
                return true;
            }
            return base.CanConvertFrom(context, sourceType);
        }

        public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
        {
            if (value is string)
            {
                return Convert.ToDouble(value);
            }
            return base.ConvertFrom(context, culture, value);
        }

        public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
        {
            if (destinationType == typeof(string))
            {
                return true;
            }
            return base.CanConvertTo(context, destinationType);
        }

        public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
        {
            if (destinationType == typeof(string))
            {
                return string.Format(FmtString, value);
            }

            return base.ConvertTo(context, culture, value, destinationType);
        }
    }

    public class Double0Converter : DoubleConverter
    {
        protected override string FmtString { get; set; } = "{0:F0}";
    }

    public class Double1Converter : DoubleConverter
    {
        protected override string FmtString { get; set; } = "{0:F1}";
    }

    public class Double8Converter : DoubleConverter
    {
        protected override string FmtString { get; set; } = "{0:0.########}";
    }
}