// ClassicalSharp copyright 2014-2016 UnknownShadow200 | Licensed under MIT
using System;

namespace ClassicalSharp {
	
	public class StringBuffer {
		
		public char[] value;
		public int Capacity;
		
		public StringBuffer(int capacity) {
			this.Capacity = capacity;
			value = new char[capacity];
		}
		
		public StringBuffer Append(int index, char c) {
			value[index] = c;
			return this;
		}
		
		public StringBuffer Append(int index, string s) {
			return Append(ref index, s);
		}
		
		public StringBuffer Append(ref int index, string s) {
			for (int i = 0; i < s.Length; i++)
				value[index++] = s[i];
			return this;
		}
		
		public StringBuffer AppendColourless(ref int index, string s) {
			for (int i = 0; i < s.Length; i++) {
				char token = s[i];
				if (token == '&')
					i++;// Skip over the following colour code.
				else
					value[index++] = token;
			}
			return this;
		}
		
		public StringBuffer Append(ref int index, char c) {
			value[index++] = c;
			return this;
		}
		
		static char[] numBuffer = new char[20];
		public StringBuffer AppendNum(ref int index, long num) {
			int numLen = MakeNum(num);
			for (int i = numLen - 1; i >= 0; i--)
				value[index++] = numBuffer[i];
			return this;
		}
		
		public StringBuffer AppendPaddedNum(ref int index, int minDigits, long num) {
			for (int i = 0; i < minDigits; i++)
				numBuffer[i] = '0';
			int numLen = Math.Max(minDigits, MakeNum(num));
			for (int i = numLen - 1; i >= 0; i--)
				value[index++] = numBuffer[i];
			return this;
		}
		
		int MakeNum(long num) {
			int len = 0;
			numBuffer[len++] = (char)('0' + (num % 10)); num /= 10;
			
			while (num > 0) {
				numBuffer[len++] = (char)('0' + (num % 10)); num /= 10;
			}
			return len;
		}
		
		public StringBuffer Clear() {
			for (int i = 0; i < Capacity; i++)
				value[i] = '\0';
			return this;
		}
		
		public void DeleteAt(int index) {
			for (int i = index; i < Capacity - 1; i++)
				value[i] = value[i + 1];
			value[Capacity - 1] = '\0';
		}
		
		public void InsertAt(int index, char c) {
			for (int i = Capacity - 1; i > index; i--)
				value[i] = value[i - 1];
			value[index] = c;
		}
		
		public void InsertAt(int index, string s) {
			for (int i = 0; i < s.Length; i++)
				InsertAt(index + i, s[i]);
		}
		
		public bool Empty {
			get {
				for (int i = 0; i < Capacity; i++) {
					if (value[i] != '\0') return false;
				}
				return true;
			}
		}
		
		public int Length {
			get {
				int len = Capacity;
				for (int i = Capacity - 1; i >= 0; i--) {
					if (value[i] != '\0') break;
					len--;
				}
				return len;
			}
		}
		
		public int TextLength {
			get {
				int len = Capacity;
				for (int i = Capacity - 1; i >= 0; i--) {
					if (value[i] != '\0' && value[i] != ' ') break;
					len--;
				}
				return len;
			}
		}
		
		public override string ToString() {
			return new String(value, 0, Length);
		}
	}
}