/*
     (C) Copyright IBM Corp. 2011
   
     THIS FILE IS PROVIDED UNDER THE TERMS OF THE ECLIPSE PUBLIC LICENSE
     ("AGREEMENT"). ANY USE, REPRODUCTION OR DISTRIBUTION OF THIS FILE
     CONSTITUTES RECIPIENTS ACCEPTANCE OF THE AGREEMENT.
   
     You can obtain a current copy of the Eclipse Public License from
     http://www.opensource.org/licenses/eclipse-1.0.php
  
    @author : Dave Blaschke, IBM, blaschke@us.ibm.com
   * 
   * Change History
   * Flag       Date        Prog         Description
   *------------------------------------------------------------------------------- 
   * 3397922    2011-08-30  blaschke-oss support OctetString 
   */
  
  package org.sentrysoftware.wbem.sblim.cimclient.internal.cim;
  
  /*-
   * ╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲
   * WBEM Java Client
   * ჻჻჻჻჻჻
   * Copyright (C) 2023 Sentry Software
   * ჻჻჻჻჻჻
   * This program is free software: you can redistribute it and/or modify
   * it under the terms of the GNU Lesser General Public License as
   * published by the Free Software Foundation, either version 3 of the
   * License, or (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Lesser Public License for more details.
   *
   * You should have received a copy of the GNU General Lesser Public
   * License along with this program.  If not, see
   * <http://www.gnu.org/licenses/lgpl-3.0.html>.
   * ╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱
   */
  
  import org.sentrysoftware.wbem.javax.cim.UnsignedInteger8;
  
  /**
   * This class represents a CIM octet string, or length-prefixed string, where
   * the length is four octets (32 bits) AND includes the four octets it occupies.
   * In other words, the length of the octet string is the number of characters in
   * the string plus four. There are three possible representations: <br>
   * <br>
   * 1) Byte array - This is an array of UnsignedInteger8 (unit8) objects. The
   * first four bytes contain the length, so the ASCII string "DEB" would be
   * represented as { 0x00, 0x00, 0x00, 0x07, 0x44, 0x45, 0x42 }<br>
   * <br>
   * 2) Hexadecimal string - This is a string of hexadecimal digits. The four
   * bytes after the initial "0x" contain the length, so the ASCII string "DEB"
   * would be represented as "0x00000007444542".<br>
   * <br>
   * 3) ASCII string<br>
   * <br>
   * One of these representations is passed into a constructor. The other
   * representations are created on demand when a get() method is invoked or when
   * the equals() method is invoked and the two octet strings have no
   * representations in common.
   */
  public class CIMOctetString {
  
  	private UnsignedInteger8 iBytes[];
  
  	private String iASCIIString;
  
  	private char iReplacementChar; // 0xFF indicates ASCII constructor used
  
  	private String iHexString;
  
  	private int iLength;
  
  	/**
  	 * Constructs a <code>CIMOctetString</code> from the given byte array.
  	 * 
  	 * @param pBytes
  	 *            Byte array representation of octet string.
  	 * @throws IllegalArgumentException
  	 */
  	public CIMOctetString(UnsignedInteger8 pBytes[]) throws IllegalArgumentException {
  		// Minimum (empty) byte array is { 0x00 0x00 0x00 0x04 }
  		if (pBytes == null || pBytes.length < 4) throw new IllegalArgumentException(
  				"Array of bytes must contain at least four bytes");
  
  		// Verify there are no null entries in byte array
  		for (int i = pBytes.length - 1; i >= 0; i--)
  			if (pBytes[i] == null) throw new IllegalArgumentException(
  					"Array of bytes must not contain any null bytes");
  
  		// Calculate length
  		this.iLength = pBytes[3].byteValue() + (pBytes[2].byteValue() * 0x100)
  				+ (pBytes[1].byteValue() * 0x10000) + (pBytes[0].byteValue() * 0x1000000);
  
  		// Verify calculated length matches actual length
 		if (this.iLength != pBytes.length) throw new IllegalArgumentException(
 				"Array of bytes contains invalid length: found " + this.iLength + ", expected "
 						+ pBytes.length);
 
 		// Save byte array in new object
 		this.iBytes = new UnsignedInteger8[this.iLength];
 		for (int i = this.iLength - 1; i >= 0; i--)
 			this.iBytes[i] = pBytes[i];
 	}
 
 	/**
 	 * Constructs a <code>CIMOctetString</code> from the given string.
 	 * 
 	 * @param pString
 	 *            String representation of octet string.
 	 * @param pIsHex
 	 *            <code>true</code> if string is hexadecimal string,
 	 *            <code>false</code> if string is ASCII string.
 	 * 
 	 * @throws IllegalArgumentException
 	 */
 	public CIMOctetString(String pString, boolean pIsHex) throws IllegalArgumentException {
 		if (pString == null) throw new IllegalArgumentException("String cannot be null");
 
 		if (pIsHex) {
 			// Minimum (empty) hexadecimal string is "0x00000004"
 			if (pString.length() < 10) throw new IllegalArgumentException(
 					"Hexadecimal string must contain \"0x\" and at least four pairs of hex digits");
 
 			// Verify hexadecimal string starts with "0x"
 			if (pString.charAt(0) != '0' || pString.charAt(1) != 'x') throw new IllegalArgumentException(
 					"Hexadecimal string must begin with \"0x\"");
 
 			// Calculate length
 			try {
 				this.iLength = Integer.parseInt(pString.substring(2, 10), 16);
 			} catch (NumberFormatException e) {
 				throw new IllegalArgumentException(
 						"Hexadecimal string length could not be parsed: " + e.toString());
 			}
 
 			// Verify calculated length matches actual length
 			if ((this.iLength * 2) + 2 != pString.length()) throw new IllegalArgumentException(
 					"Hexadecimal string contains invalid length: found " + this.iLength
 							+ ", expected " + ((pString.length() - 2 / 2)));
 
 			// Verify remainder of hexadecimal string contains only hexadecimal
 			// digits
 			for (int i = pString.length() - 1; i >= 10; i--) {
 				char ch = pString.charAt(i);
 				if (!((ch >= '0' && ch <= '9') || (ch >= 'a' && ch <= 'f') || (ch >= 'A' && ch <= 'F'))) throw new IllegalArgumentException(
 						"Hexadecimal string could not be parsed, invalid character \'" + ch
 								+ "\' at index " + i);
 			}
 
 			// Save hexadecimal string in new object
 			this.iHexString = new String(pString);
 		} else {
 			// Calculate length
 			this.iLength = pString.length() + 4;
 
 			// Save ASCII string in new object and indicate constructor used
 			this.iASCIIString = new String(pString);
 			this.iReplacementChar = 0xFF;
 		}
 	}
 
 	/**
 	 * Takes a CIM octet string and returns <code>true</code> if it is equal to
 	 * this CIM octet string. Otherwise, it returns <code>false</code>. Two
 	 * octet strings are considered equal if all of their common representations
 	 * are equal. If the octet strings have no representations in common, this
 	 * method will build the missing one, starting with byte array and then
 	 * hexadecmial string.
 	 * 
 	 * NOTE: The ASCII string representation is only considered if both octet
 	 * strings were constructed with an ASCII string.
 	 * 
 	 * @param pObj
 	 *            The object to be compared a CIM element.
 	 * @return <code>true</code> if the specified CIM octet string equals this
 	 *         CIM octet string, <code>false</code> otherwise.
 	 */
 	@Override
 	public synchronized boolean equals(Object pObj) {
 		// Verify parameter is CIMOctetString instance
 		if (!(pObj instanceof CIMOctetString)) return false;
 
 		CIMOctetString that = (CIMOctetString) pObj;
 		int numCompares = 0;
 
 		// Verify lengths are same
 		if (this.iLength != that.iLength) return false;
 
 		// Verify byte arrays match if both non-null
 		if (this.iBytes != null && that.iBytes != null) {
 			for (int i = this.iLength - 1; i >= 0; i--)
 				if (this.iBytes[i].byteValue() != that.iBytes[i].byteValue()) return false;
 			numCompares++;
 		}
 
 		// Verify hexadecimal strings match if both non-null
 		if (this.iHexString != null && that.iHexString != null) {
 			if (!this.iHexString.equalsIgnoreCase(that.iHexString)) return false;
 			numCompares++;
 		}
 
 		// Verify ASCII strings match if both non-null
 		if (this.iASCIIString != null && that.iASCIIString != null
 				&& this.iReplacementChar == that.iReplacementChar) {
 			if (!this.iASCIIString.equalsIgnoreCase(that.iASCIIString)) return false;
 			numCompares++;
 		}
 
 		// Octet strings equal if at least one representation equal
 		if (numCompares > 0) return true;
 
 		// At this point, the two CIMOctetString instances have no
 		// representations in common - time to make one
 
 		if (this.iBytes != null && that.iBytes == null) {
 			that.getBytes();
 			if (this.iBytes != null && that.iBytes != null) {
 				for (int i = this.iLength - 1; i >= 0; i--)
 					if (this.iBytes[i].byteValue() != that.iBytes[i].byteValue()) return false;
 				numCompares++;
 			}
 		}
 
 		// Octet strings equal if byte arrays equal
 		if (numCompares > 0) return true;
 
 		if (this.iBytes == null && that.iBytes != null) {
 			getBytes();
 			if (this.iBytes != null && that.iBytes != null) {
 				for (int i = this.iLength - 1; i >= 0; i--)
 					if (this.iBytes[i].byteValue() != that.iBytes[i].byteValue()) return false;
 				numCompares++;
 			}
 		}
 
 		// Octet strings equal if byte arrays equal
 		if (numCompares > 0) return true;
 
 		if (this.iHexString != null && that.iHexString == null) {
 			that.getHexString();
 			if (this.iHexString != null && that.iHexString != null) {
 				if (!this.iHexString.equalsIgnoreCase(that.iHexString)) return false;
 				numCompares++;
 			}
 		}
 
 		// Octet strings equal if byte arrays equal
 		if (numCompares > 0) return true;
 
 		if (this.iHexString == null && that.iHexString != null) {
 			getHexString();
 			if (this.iHexString != null && that.iHexString != null) {
 				if (!this.iHexString.equalsIgnoreCase(that.iHexString)) return false;
 				numCompares++;
 			}
 		}
 
 		// Octet strings equal if byte arrays equal
 		if (numCompares > 0) return true;
 
 		return false;
 	}
 
 	/**
 	 * Returns ASCII string representation of octet string with non-printable
 	 * characters replaced by <code>pReplacementChar</code>. If the ASCII string
 	 * has not yet been created, it is created from the byte array or
 	 * hexadecimal string.
 	 * 
 	 * @param pReplacementChar
 	 *            Replacement character for non-printable characters which must
 	 *            be between 0x20 and 0x7E, inclusive.
 	 * @return ASCII string representation of octet string.
 	 */
 	public synchronized String getASCIIString(char pReplacementChar) {
 		// If ASCII string constructor used, return original string
 		if (this.iASCIIString != null && this.iReplacementChar == 0xFF) return this.iASCIIString;
 
 		// Verify replacement character is printable
 		if (pReplacementChar <= 0x1F || pReplacementChar >= 0x7F) throw new IllegalArgumentException(
 				"Replacement character not printable");
 
 		// If we already did this once, return previous string
 		if (this.iASCIIString != null && this.iReplacementChar == pReplacementChar) return this.iASCIIString;
 
 		// Construct new ASCII string
 		StringBuilder str = new StringBuilder("");
 		if (this.iBytes != null) {
 			for (int i = 4; i < this.iBytes.length; i++) {
 				char ch = (char) this.iBytes[i].byteValue();
 				if (ch <= 0x1F || ch >= 0x7F) str.append(pReplacementChar);
 				else str.append(ch);
 			}
 		} else /* (this.iHexString != null) */{
 			for (int i = 10; i < this.iHexString.length(); i += 2) {
 				char ch = (char) Integer.parseInt(this.iHexString.substring(i, i + 2), 16);
 				if (ch <= 0x1F || ch >= 0x7F) str.append(pReplacementChar);
 				else str.append(ch);
 			}
 		}
 
 		// Save ASCII string in new object and indicate which replacement
 		// character used
 		this.iASCIIString = new String(str);
 		this.iReplacementChar = pReplacementChar;
 
 		return this.iASCIIString;
 	}
 
 	/**
 	 * Returns byte array representation of octet string. If the byte array has
 	 * not yet been created, it is created from the hexadecimal string or ASCII
 	 * string.
 	 * 
 	 * @return Byte array representation of octet string.
 	 */
 	public synchronized UnsignedInteger8[] getBytes() {
 		if (this.iBytes != null) return this.iBytes;
 
 		if (this.iHexString != null) {
 			convertHexStringToBytes();
 		} else /* if (this.iASCIIString != null) */{
 			convertASCIIStringToBytes();
 		}
 
 		return this.iBytes;
 	}
 
 	/**
 	 * Returns hexadecimal string representation of octet string. If the
 	 * hexadecimal string has not yet been created, it is created from the byte
 	 * array or ASCII string.
 	 * 
 	 * @return Hexadecimal string representation of octet string.
 	 */
 	public synchronized String getHexString() {
 		if (this.iHexString != null) return this.iHexString;
 
 		if (this.iBytes != null) {
 			convertBytesToHexString();
 		} else /* if (this.iASCIIString != null) */{
 			convertASCIIStringToHexString();
 		}
 
 		return this.iHexString;
 	}
 
 	/**
 	 * Returns hash code value for octet string.
 	 * 
 	 * @return Hash code value for octet string.
 	 */
 	@Override
 	public int hashCode() {
 		return toString().toLowerCase().hashCode();
 	}
 
 	/**
 	 * Returns length of octet string, where length is number of octets plus
 	 * four.
 	 * 
 	 * @return Length of octet string.
 	 */
 	public int length() {
 		return this.iLength;
 	}
 
 	/**
 	 * Returns string representation of octet string.
 	 * 
 	 * @return String representation of octet string.
 	 */
 	@Override
 	public String toString() {
 		return getHexString();
 	}
 
 	private void convertBytesToHexString() {
 		// Start with "0x"
 		StringBuilder str = new StringBuilder("0x");
 
 		// Append length
 		String len = Integer.toHexString(this.iLength);
 		for (int i = 8 - len.length(); i > 0; i--)
 			str.append('0');
 		str.append(len);
 
 		// Append string
 		for (int i = 4; i < this.iLength; i++) {
 			String octet = Integer.toHexString(this.iBytes[i].intValue());
 			if (octet.length() == 1) str.append('0');
 			str.append(octet);
 		}
 
 		// Save hexadecimal string in new object
 		this.iHexString = new String(str);
 
 		// debug("convertBytesToHexString: from {" + toBytesString() + "} to \""
 		// + this.iHexString + "\"");
 	}
 
 	private void convertHexStringToBytes() {
 		// Save byte array in new object
 		this.iBytes = new UnsignedInteger8[this.iLength];
 
 		// Convert each octet in hexadecimal string to byte
 		for (int idxByte = 0, idxStr = 2, len = this.iHexString.length(); idxStr < len; idxByte++, idxStr += 2) {
 			short s;
 			try {
 				s = Short.parseShort(this.iHexString.substring(idxStr, idxStr + 2), 16);
 			} catch (NumberFormatException e) {
 				throw new IllegalArgumentException("Hex string length could not be parsed: "
 						+ e.toString());
 			}
 			this.iBytes[idxByte] = new UnsignedInteger8(s);
 		}
 
 		// debug("convertHexStringToBytes: from \"" + this.iHexString +
 		// "\" to {" + toBytesString() + "}");
 	}
 
 	private void convertASCIIStringToBytes() {
 		// Save byte array in new object
 		this.iBytes = new UnsignedInteger8[this.iLength];
 
 		// Convert length
 		this.iBytes[0] = new UnsignedInteger8((short) ((this.iLength >> 24) & 0xFF));
 		this.iBytes[1] = new UnsignedInteger8((short) ((this.iLength >> 16) & 0xFF));
 		this.iBytes[2] = new UnsignedInteger8((short) ((this.iLength >> 8) & 0xFF));
 		this.iBytes[3] = new UnsignedInteger8((short) (this.iLength & 0xFF));
 
 		// Convert each character in ASCII string to byte
 		for (int idxStr = 0, idxByte = 4; idxStr < this.iASCIIString.length(); idxStr++, idxByte++)
 			this.iBytes[idxByte] = new UnsignedInteger8((short) (this.iASCIIString.charAt(idxStr)));
 
 		// debug("convertASCIIStringToBytes: from \"" + this.iASCIIString +
 		// "\" to {" + toBytesString() + "}");
 	}
 
 	private void convertASCIIStringToHexString() {
 		// Start with "0x"
 		StringBuilder str = new StringBuilder("0x");
 
 		// Append length
 		String len = Integer.toHexString(this.iLength);
 		for (int i = 8 - len.length(); i > 0; i--)
 			str.append('0');
 		str.append(len);
 
 		// Append string
 		for (int idxAsc = 0, idxHex = 10; idxAsc < this.iASCIIString.length(); idxAsc++, idxHex++) {
 			String octet = Integer.toHexString((this.iASCIIString.charAt(idxAsc)));
 			if (octet.length() == 1) str.append('0');
 			str.append(octet);
 		}
 
 		// Save hexadecimal string in new object
 		this.iHexString = new String(str);
 
 		// debug("convertASCIIStringToHexString: from \"" + this.iASCIIString +
 		// "\" to \"" + this.iHexString + "\"");
 	}
 
 	// private String toBytesString() {
 	// StringBuilder str = new StringBuilder();
 	//
 	// for (int i = 0; i < this.iLength; i++) {
 	// String octet = Integer.toHexString((this.iBytes[i].intValue()));
 	// if (i > 0) str.append(' ');
 	// if (octet.length() == 1) str.append('0');
 	// str.append(octet);
 	// }
 	// return new String(str);
 	// }
 
 	// private void debug(String str) {
 	// System.out.println(str);
 	// }
 }