using System;
using System.Linq;
using Cosmos.IL2CPU.Plugs;

namespace Cosmos.IL2CPU.X86.Plugs.CustomImplementations.MS.System {
	[Plug(Target = typeof(String), IsMicrosoftdotNETOnly = true)]
	[PlugField(FieldId = "$$Storage$$", FieldType = typeof(char[]))]
	[PlugField(FieldId = "System.Char System.String.m_firstChar", IsExternalValue = true)]
	public static class StringImpl {
		//[PlugMethod(Signature = "System_Void__System_String__ctor_System_Char____System_Int32__System_Int32_")]
		public static unsafe void Ctor(String aThis, [FieldAccess(Name = "$$Storage$$")]ref Char[] aStorage, Char[] aChars, int aStartIndex, int aLength,
			[FieldAccess(Name = "System.Int32 System.String.m_stringLength")] ref int aStringLength,
			[FieldAccess(Name = "System.Int32 System.String.m_arrayLength")] ref int aArrayLength,
			[FieldAccess(Name = "System.Char System.String.m_firstChar")] ref char* aFirstChar) {
			Char[] newChars = new Char[aLength];
			Array.Copy(aChars, aStartIndex, newChars, 0, aLength);
			aStorage = newChars;
			aStringLength = newChars.Length;
			aArrayLength = newChars.Length;
			fixed (char* xFirstChar = &aStorage[0]) {
				aFirstChar = xFirstChar;
			}
		}

		//[PlugMethod(Signature = "System_Void__System_String__ctor_System_Char___")]
		public static unsafe void Ctor(String aThis, [FieldAccess(Name = "$$Storage$$")] ref Char[] aStorage, Char[] aChars,
			[FieldAccess(Name = "System.Int32 System.String.m_stringLength")]ref int aStringLength,
			[FieldAccess(Name = "System.Int32 System.String.m_arrayLength")] ref int aArrayLength,
			[FieldAccess(Name = "System.Char System.String.m_firstChar")] ref char* aFirstChar) {
			aStorage = aChars;
			aStringLength = aChars.Length;
			aArrayLength = aChars.Length;
			fixed(char* xFirstChar = &aStorage[0]){
				aFirstChar = xFirstChar;
			}
		}

        [PlugMethod(Signature="System_Int32__System_String_get_Length__")]
		public static unsafe int get_Length(int* aThis, [FieldAccess(Name = "System.Int32 System.String.m_stringLength")]ref int aLength) {
			return aLength;
		}

		public static unsafe char get_Chars(uint* aThis, [FieldAccess(Name = "System.Char System.String.m_firstChar")]ref char* aStorage, int aIndex) {
			return aStorage[aIndex];
		}

        public static char[] ToCharArray(string aThis, [FieldAccess(Name = "$$Storage$$")] ref char[] aChars)
        {
            return aChars;
        }

		public static string FastAllocateString(int length) {
			return new String(new char[length]);
		}

		//public static unsafe string GetStringForStringBuilder(string value, int startIndex, int length, int capacity) {
		//    string str = FastAllocateString(capacity);
		//    if (value.Length == 0x0) {
		//        str.SetLength(0x0);
		//        return str;
		//    }
		//    fixed (char* chRef = &str.m_firstChar) {
		//        fixed (char* chRef2 = &value.m_firstChar) {
		//            wstrcpy(chRef, chRef2 + startIndex, length);
		//        }
		//    }
		//    str.SetLength(length);
		//    return str;
		//    return null;
		//}

		public static unsafe void wstrcpy(char* dmem, char* smem, int charCount) {
			for (int i = 0; i < charCount; i++) {
				dmem[i] = smem[i];
			}
		}
	}

  //StringImpl2 plugs StringImpl which is also a plug????
	//[Plug(Target = typeof(Cosmos.IL2CPU.CustomImplementation.System.StringImpl))]
	public static class StringImpl2 {
        //System_Int32__System_String_get_Length__
        [PlugMethod(Enabled=false)]
        public static unsafe uint GetStorage(uint* aStringPtr, [FieldAccess(Name = "$$Storage$$")]ref uint aStorage) {
			return aStorage;
		}

        [PlugMethod(Signature = "System_Char____Cosmos_IL2CPU_CustomImplementation_System_GetStorageArray_System_String__")]
        public static char[] GetStorageArray(string aThis, [FieldAccess(Name = "$$Storage$$")]ref char[] aStorage)
        {
            return aStorage;
        }

        [PlugMethod(Enabled = false)]
		public static void FakeMethod() {
			//char[] xThis = null;
			//CustomImplementation.System.StringImpl.Ctor(null, ref xThis, null);
		}
	}
}