franta-hg@54: /**
franta-hg@54:  * Alt2XML
franta-hg@54:  * Copyright © 2014 František Kučera (frantovo.cz)
franta-hg@54:  *
franta-hg@54:  * This program is free software: you can redistribute it and/or modify
franta-hg@54:  * it under the terms of the GNU General Public License as published by
franta-hg@54:  * the Free Software Foundation, either version 3 of the License, or
franta-hg@54:  * (at your option) any later version.
franta-hg@54:  *
franta-hg@54:  * This program is distributed in the hope that it will be useful,
franta-hg@54:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
franta-hg@54:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
franta-hg@54:  * GNU General Public License for more details.
franta-hg@54:  *
franta-hg@54:  * You should have received a copy of the GNU General Public License
franta-hg@54:  * along with this program. If not, see <http://www.gnu.org/licenses/>.
franta-hg@54:  */
franta-hg@54: package cz.frantovo.alt2xml.cli;
franta-hg@54: 
franta-hg@54: import java.io.File;
franta-hg@67: import java.util.Arrays;
franta-hg@67: import java.util.Collection;
franta-hg@54: 
franta-hg@54: /**
franta-hg@54:  * Converts command line arguments from String array to object.
franta-hg@54:  * Checks basic constraints (if only supported options are used and if they have correct number of
franta-hg@54:  * parameters)
franta-hg@54:  *
franta-hg@54:  * @author Ing. František Kučera (frantovo.cz)
franta-hg@54:  */
franta-hg@54: public class CLIParser {
franta-hg@54: 
franta-hg@55: 	public CLIOptions parseOptions(String[] args) throws CLIParserException {
franta-hg@54: 		CLIOptions options = new CLIOptions();
franta-hg@54: 
franta-hg@54: 		for (int i = 0; i < args.length; i++) {
franta-hg@54: 			String arg = args[i];
franta-hg@54: 
franta-hg@55: 			boolean matches = false;
franta-hg@55: 
franta-hg@54: 			for (Token t : Token.values()) {
franta-hg@54: 				if (t.matches(arg)) {
franta-hg@55: 					int parsedArgs = t.parse(args, i, options);
franta-hg@55: 					i = i + parsedArgs;
franta-hg@55: 					matches = true;
franta-hg@54: 				}
franta-hg@54: 			}
franta-hg@54: 
franta-hg@55: 			if (!matches) {
franta-hg@55: 				throw new CLIParserException("Unknown option: " + arg);
franta-hg@55: 			}
franta-hg@54: 		}
franta-hg@54: 
franta-hg@55: 		// Default output:
franta-hg@54: 		options.setOutputStream(System.out);
franta-hg@54: 
franta-hg@54: 		return options;
franta-hg@54: 	}
franta-hg@54: 
franta-hg@54: 	private static String fetchNext(String[] args, int index) throws CLIParserException {
franta-hg@54: 		if (index < args.length) {
franta-hg@54: 			return args[index];
franta-hg@54: 		} else {
franta-hg@54: 			throw new CLIParserException("Expecting value for option: " + args[index - 1]);
franta-hg@54: 		}
franta-hg@54: 	}
franta-hg@54: 
franta-hg@54: 	private static enum Token {
franta-hg@54: 
franta-hg@54: 		INPUT_FILE("--input-file") {
franta-hg@54: 					@Override
franta-hg@54: 					public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
franta-hg@54: 						int originalIndex = index;
franta-hg@54: 						options.setInputFile(new File(fetchNext(args, ++index)));
franta-hg@54: 						return index - originalIndex;
franta-hg@54: 					}
franta-hg@54: 				},
franta-hg@54: 		INPUT_STDIN("--input-stdin") {
franta-hg@54: 					@Override
franta-hg@54: 					public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
franta-hg@54: 						options.setInputStream(System.in);
franta-hg@54: 						return 0;
franta-hg@54: 					}
franta-hg@54: 				},
franta-hg@67: 		SYSTEM_ID("--system-id", "--input-url") {
franta-hg@54: 					@Override
franta-hg@54: 					public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
franta-hg@54: 						int originalIndex = index;
franta-hg@54: 						options.setSystemId(fetchNext(args, ++index));
franta-hg@54: 						return index - originalIndex;
franta-hg@54: 					}
franta-hg@54: 				},
franta-hg@54: 		READER_PROPERTY("--reader-property") {
franta-hg@54: 					@Override
franta-hg@54: 					public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
franta-hg@54: 						int originalIndex = index;
franta-hg@54: 						String name = fetchNext(args, ++index);
franta-hg@54: 						String value = fetchNext(args, ++index);
franta-hg@54: 						options.addReaderProperty(name, value);
franta-hg@54: 						return index - originalIndex;
franta-hg@54: 					}
franta-hg@54: 				},
franta-hg@98: 		READER_FEATURE("--reader-feature") {
franta-hg@98: 					@Override
franta-hg@98: 					public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
franta-hg@98: 						int originalIndex = index;
franta-hg@98: 						String name = fetchNext(args, ++index);
franta-hg@98: 						String value = fetchNext(args, ++index);
franta-hg@98: 						options.addReaderFeature(name, Boolean.valueOf(value));
franta-hg@98: 						return index - originalIndex;
franta-hg@98: 					}
franta-hg@98: 				},
franta-hg@54: 		ACTION("--action") {
franta-hg@54: 					@Override
franta-hg@54: 					public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
franta-hg@54: 						int originalIndex = index;
franta-hg@54: 						options.setAction(fetchNext(args, ++index));
franta-hg@54: 						return index - originalIndex;
franta-hg@54: 					}
franta-hg@54: 				},
franta-hg@54: 		ACTION_PROPERTY("--action-property") {
franta-hg@54: 					@Override
franta-hg@54: 					public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
franta-hg@54: 						int originalIndex = index;
franta-hg@54: 						String name = fetchNext(args, ++index);
franta-hg@54: 						String value = fetchNext(args, ++index);
franta-hg@54: 						options.addActionProperty(name, value);
franta-hg@54: 						return index - originalIndex;
franta-hg@54: 					}
franta-hg@54: 				},
franta-hg@54: 		ACTION_DATA("--") {
franta-hg@54: 					@Override
franta-hg@54: 					public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
franta-hg@54: 						int originalIndex = index;
franta-hg@54: 						for (index++; index < args.length; index++) {
franta-hg@54: 							options.addActionData(args[index]);
franta-hg@54: 						}
franta-hg@54: 						return index - originalIndex;
franta-hg@54: 					}
franta-hg@54: 				};
franta-hg@54: 
franta-hg@67: 		private final Collection<String> options;
franta-hg@54: 
franta-hg@67: 		private Token(String... options) {
franta-hg@67: 			this.options = Arrays.asList(options);
franta-hg@54: 		}
franta-hg@54: 
franta-hg@54: 		/**
franta-hg@54: 		 * @param option e.g. „--input-file“
franta-hg@54: 		 * @return whether option is this token
franta-hg@54: 		 */
franta-hg@54: 		public boolean matches(String option) {
franta-hg@67: 			return options.contains(option);
franta-hg@54: 		}
franta-hg@54: 
franta-hg@54: 		/**
franta-hg@54: 		 * Parse String arguments and fill values into the options object.
franta-hg@54: 		 *
franta-hg@54: 		 * @param args CLI arguments
franta-hg@54: 		 * @param index index of the option matched by this token, like „--input-file“
franta-hg@54: 		 * @param options object to be filled
franta-hg@54: 		 * @return number of parsed arguments – if option has no arguments (just boolean flag),
franta-hg@54: 		 * return 0, otherwise return positive integer: number of eaten arguments.
franta-hg@54: 		 * @throws CLIParserException
franta-hg@54: 		 */
franta-hg@54: 		public abstract int parse(String[] args, int index, CLIOptions options) throws CLIParserException;
franta-hg@54: 	}
franta-hg@54: }