/*

* Copyright (c) 2008 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:

*

* Parameter tokenizer is used to parse function parameters lists

*

*/

package com.nokia.tracebuilder.source;

import java.util.List;

/**

 * Parameter tokenizer is used to parse function parameters lists

 * 

 */

public class SourceParameterTokenizer {

	/**

	 * The source parser

	 */

	private SourceParser parser;

	/**

	 * The offset where to start the tokenizer

	 */

	private int offset;

	/**

	 * Slip next whitespace

	 */

	private boolean skipNextWhiteSpace;

	/**

	 * Constructor

	 * 

	 * @param parser

	 *            the source parser

	 * @param offset

	 *            offset to the start of parameter

	 */

	public SourceParameterTokenizer(SourceParser parser, int offset) {

		this.parser = parser;

		this.offset = offset;

	}

	/**

	 * Parses a list of parameters (a, b, c) and stores the values into the

	 * given list.

	 * 

	 * @param list

	 *            the list of parameters

	 * @param findSeparator

	 *            if true, the processing stops after ';' or '{' character. If

	 *            false, processing stops after ')' at end of parameters

	 * @return index at end of parameters

	 * @throws SourceParserException

	 *             if processing fails

	 */

	public int tokenize(List<String> list, boolean findSeparator)

			throws SourceParserException {

		TokenizerSearchData data = new TokenizerSearchData();

		data.itr = parser.createIterator(offset, SourceParser.SKIP_WHITE_SPACES

				| SourceParser.SKIP_COMMENTS);

		boolean finished = false;

		while (data.itr.hasNext() && !finished) {

			data.value = data.itr.next();

			if (!data.inQuotes && data.value == '\"') {

				data.inQuotes = true;

				data.hasData = true;

			} else if (data.inQuotes) {

				processInQuotesChar(data);

			} else if (data.complete) {

				processEndOfParametersChar(data);

			} else if (data.value == '(') {

				processOpeningBracket(data);

			} else if (data.value == ',' || data.value == ')') {

				processCommaOrClosingBracket(list, data);

			} else if (data.value == ';' || data.value == '{'

					|| data.value == '}') {

				throw new SourceParserException(

						SourceErrorCodes.UNEXPECTED_PARAMETER_SEPARATOR);

			} else {

				// Raises a flag that there is some data. processOpeningBracket

				// no longer interprets the next bracket as opening bracket

				if (data.openBracketCount > 0) {

					data.hasData = true;

				}

			}

			finished = ((data.complete && !findSeparator) || (data.endFound && findSeparator));

		}

		if (!data.complete) {

			throw new SourceParserException(

					SourceErrorCodes.UNEXPECTED_END_OF_FILE);

		}

		if (data.openBracketCount != 0) {

			throw new SourceParserException(SourceErrorCodes.BRACKET_MISMATCH);

		}

		return data.itr.currentIndex() + 1;

	}

	/**

	 * Parses list of parameters with types (int a, int b, int c) and stores the

	 * values into the given list.

	 * 

	 * @param list

	 *            the list of parameters

	 * @return index at end of parameters

	 * @throws SourceParserException

	 *             if processing fails

	 */

	public int tokenizeTyped(List<SourceParameter> list)

			throws SourceParserException {

		TokenizerSearchData data = new TokenizerSearchData();

		try {

			data.itr = parser

					.createIterator(offset, SourceParser.SKIP_WHITE_SPACES

							| SourceParser.SKIP_COMMENTS);

			data.sourceParameter = new SourceParameter();

			while (data.itr.hasNext() && !data.complete) {

				data.value = data.itr.next();

				// Check if there was array start or end character and then

				// space. It would mean that the parameter continues and more

				// should be parsed.

				if (skipNextWhiteSpace) {

					skipNextWhiteSpace = false;

					if (data.itr.hasSkipped()) {

						data.value = data.itr.next();

					}

				}

				if (data.value == '\"') {

					throw new SourceParserException(

							SourceErrorCodes.UNEXPECTED_QUOTE_CHARACTER);

				} else if (data.value == '(') {

					processOpeningBracket(data);

				} else if (data.value == ',' || data.value == ')') {

					processCommaOrClosingBracket(list, data);

				} else if (data.value == ';' || data.value == '{'

						|| data.value == '}') {

					throw new SourceParserException(

							SourceErrorCodes.UNEXPECTED_PARAMETER_SEPARATOR);

					// Array start or end character.

				} else if (data.value == '<' || data.value == '>') {

					skipNextWhiteSpace = true;

				} else if (data.itr.hasSkipped()) {

					processNameValueSeparator(data);

				}

			}

			if (!data.complete) {

				throw new SourceParserException(

						SourceErrorCodes.UNEXPECTED_END_OF_FILE);

			}

		} catch (SourceParserException e) {

			// Resets all source locations if parser fails

			for (int i = 0; i < list.size(); i++) {

				list.get(i).getSourceLocation().dereference();

			}

			throw e;

		}

		return data.itr.currentIndex() + 1;

	}

	/**

	 * Processes a separator character and updates the current SourceParameter

	 * object in the search data

	 * 

	 * @param data

	 *            the search data

	 * @throws SourceParserException

	 *             if processing fails

	 */

	private void processNameValueSeparator(TokenizerSearchData data)

			throws SourceParserException {

		// If the parameter is empty, the previous index will point

		// to index preceeding tagStartIndex

		int previous = data.itr.previousIndex();

		if (previous >= data.tagStartIndex) {

			int endIndex = previous + 1;

			if (data.sourceParameter.getType() == null) {

				processNameValueSeparatorNoType(data, endIndex);

			} else if (data.sourceParameter.getName() == null) {

				processNameValueSeparatorNoName(data, endIndex);

			}

			data.tagStartIndex = data.itr.currentIndex();

		}

	}

	/**

	 * Processes a name-value separator when there is no name

	 * 

	 * @param data

	 *            the search data

	 * @param endIndex

	 *            the end index of the parameters

	 * @throws SourceParserException

	 *             if processing fails

	 */

	private void processNameValueSeparatorNoName(TokenizerSearchData data,

			int endIndex) throws SourceParserException {

		String name = parser.getSource().get(data.tagStartIndex,

				endIndex - data.tagStartIndex);

		boolean startFound = false;

		int start = 0;

		int end = name.length();

		for (int i = 0; i < name.length(); i++) {

			char c = name.charAt(i);

			if (c == '&' || c == '*') {

				if (c == '&') {

					data.sourceParameter.setReference();

				} else {

					data.sourceParameter.addPointer();

				}

				if (!startFound) {

					start++;

				} else {

					end--;

				}

			} else {

				startFound = true;

			}

		}

		name = name.substring(start, end);

		if (name.length() > 0) {

			if (isParameterTypeQualifier(name)) {

				// Qualifiers between type and name are ignored

				// For example TInt const* aValue

			} else {

				data.sourceParameter.setName(name);

			}

		}

	}

	/**

	 * Processes a name-value separator when there is no value

	 * 

	 * @param data

	 *            the search data

	 * @param endIndex

	 *            the end index of the parameters

	 * @throws SourceParserException

	 *             if processing fails

	 */

	private void processNameValueSeparatorNoType(TokenizerSearchData data,

			int endIndex) throws SourceParserException {

		String type = parser.getSource().get(data.tagStartIndex,

				endIndex - data.tagStartIndex);

		if (isParameterTypeQualifier(type)) {

			data.sourceParameter.addQualifier(type);

		} else {

			for (int i = type.length() - 1; i >= 0; i--) {

				if (type.charAt(i) == '&') {

					data.sourceParameter.setReference();

					if (i == 0) {

						type = ""; //$NON-NLS-1$

					}

				} else if (type.charAt(i) == '*') {

					data.sourceParameter.addPointer();

					if (i == 0) {

						type = ""; //$NON-NLS-1$

					}

				} else {

					if (i != type.length() - 1) {

						type = type.substring(0, i + 1);

					}

					i = -1;

				}

			}

			if (type.length() > 0) {

				// Remove spaces

				type = type.replace(" ", ""); //$NON-NLS-1$ //$NON-NLS-2$

				data.sourceParameter.setType(type);

			}

		}

	}

	/**

	 * Checks if parameter type if a qualifier or not

	 * 

	 * @param type

	 *            the type to be checked

	 * @return true if qualifier, false if not

	 */

	private boolean isParameterTypeQualifier(String type) {

		boolean retval = false;

		for (String element : SourceConstants.PARAMETER_QUALIFIERS) {

			if (type.equals(element)) {

				retval = true;

			}

		}

		return retval;

	}

	/**

	 * Processes a parameter separator or closing bracket

	 * 

	 * @param list

	 *            the list of existing parameters

	 * @param data

	 *            the search data

	 * @throws SourceParserException

	 *             if invalid character is encountered

	 */

	@SuppressWarnings("unchecked")

	private void processCommaOrClosingBracket(List list,

			TokenizerSearchData data) throws SourceParserException {

		// This method is called from both tokenize functions. One uses

		// List<String> and other List<SourceParameter>

		// Thus this uses List and @SuppressWarnings

		if (data.openBracketCount == data.initialBracketCount) {

			if (data.sourceParameter != null) {

				// If processing typed parameter list, the name and type are

				// stored into a SourceParameter object, which is then added

				// to list

				processNameValueSeparator(data);

				if (data.sourceParameter.getType() != null) {

					SourceLocation location = new SourceLocation(parser,

							data.paramStartIndex, data.itr.currentIndex()

									- data.paramStartIndex);

					data.sourceParameter.setSourceLocation(location);

					list.add(data.sourceParameter);

					data.sourceParameter = new SourceParameter();

				}

			} else {

				// In this case the list contains strings.

				int previous = data.itr.previousIndex();

				if (previous >= data.tagStartIndex) {

					int endIndex = data.itr.previousIndex() + 1;

					list.add(parser.getSource().get(data.tagStartIndex,

							endIndex - data.tagStartIndex));

				} else {

					list.add(""); //$NON-NLS-1$

				}

			}

			if (data.value == ')') {

				data.complete = true;

				data.openBracketCount--;

			} else {

				data.tagStartIndex = data.itr.nextIndex();

				data.paramStartIndex = data.tagStartIndex;

			}

		} else if (data.openBracketCount > data.initialBracketCount) {

			if (data.value == ')') {

				data.openBracketCount--;

			}

		} else {

			if (data.value == ')') {

				throw new SourceParserException(

						SourceErrorCodes.BRACKET_MISMATCH);

			}

			throw new SourceParserException(

					SourceErrorCodes.UNEXPECTED_PARAMETER_SEPARATOR);

		}

	}

	/**

	 * Processes an opening bracket

	 * 

	 * @param data

	 *            the search data

	 */

	private void processOpeningBracket(TokenizerSearchData data) {

		data.openBracketCount++;

		if (!data.hasData) {

			// The number of initial '(' characters is stored. The

			// parameters are assumed to end when the corresponding ')'

			// character is encountered

			data.tagStartIndex = data.itr.nextIndex();

			data.paramStartIndex = data.tagStartIndex;

			data.initialBracketCount = data.openBracketCount;

		}

	}

	/**

	 * Process a character when in quotes

	 * 

	 * @param data

	 *            the search data

	 */

	private void processInQuotesChar(TokenizerSearchData data) {

		if (data.value == '\"' && data.previousValue != '\\') {

			data.inQuotes = false;

		}

		data.previousValue = data.value;

	}

	/**

	 * Processes a character found after the closing bracket

	 * 

	 * @param data

	 *            the data

	 * @throws SourceParserException

	 *             if invalid characters are found

	 */

	private void processEndOfParametersChar(TokenizerSearchData data)

			throws SourceParserException {

		if (data.value == ';' || data.value == '{') {

			data.endFound = true;

		} else if (data.value == ')') {

			data.openBracketCount--;

		} else if (!Character.isWhitespace(data.value)) {

			throw new SourceParserException(SourceErrorCodes.BRACKET_MISMATCH);

		}

	}

}