package info.globalcode.sql.dk;

 import java.sql.Types;

 import java.util.ArrayList;

 import java.util.Collections;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 /**

  *

  * @author Ing. František Kučera (frantovo.cz)

  */

 public class CLIParser {

 	public static final String TYPE_NAME_SEPARATOR = ":";

 	private final Map<String, Integer> types;

 	public CLIParser() {

 		Map<String, Integer> m = new HashMap<>();

 		m.put("int", Types.INTEGER);

 		m.put("string", Types.VARCHAR);

 		m.put("boolean", Types.BOOLEAN);

 		/**

 		 * TODO: more types

 		 */

 		types = Collections.unmodifiableMap(m);

 	}

 	public CLIOptions parseOptions(String[] args) {

 		CLIOptions options = new CLIOptions();

 		List<Integer> numberedTypes = new ArrayList<>();

 		Map<String, Integer> namedTypes = new HashMap<>();

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

 			String arg = args[i];

 			switch (arg) {

 				case Tokens.TYPES:

 					String typesString = fetchNext(args, ++i);

 					for (String oneType : typesString.split("\\s*,\\s*")) {

 						int sepatratorIndex = oneType.indexOf(TYPE_NAME_SEPARATOR);

 						if (sepatratorIndex == -1) {

 							numberedTypes.add(getType(oneType));

 						} else {

 							String namePart = oneType.substring(0, sepatratorIndex);

 							String typePart = oneType.substring(sepatratorIndex + TYPE_NAME_SEPARATOR.length(), oneType.length());

 							namedTypes.put(namePart, getType(typePart));

 						}

 					}

 					break;

 				case Tokens.NAME_PREFIX:

 					options.setNamePrefix(fetchNext(args, ++i));

 					break;

 				case Tokens.DB:

 					options.setDatabaseName(fetchNext(args, ++i));

 					break;

 				case Tokens.SQL:

 					options.setSql(fetchNext(args, ++i));

 					options.setCommandType(CLIOptions.COMMAND_TYPE.QUERY);

 					break;

 				case Tokens.SQL_UPDATE:

 				case Tokens.SQL_INSERT:

 					options.setSql(fetchNext(args, ++i));

 					options.setCommandType(CLIOptions.COMMAND_TYPE.UPDATE);

 					break;

 				case Tokens.BATCH:

 					options.setBatch(true);

 					break;

 				case Tokens.DATA: // --data is the last option

 					for (i++; i < args.length; i++) {

 						arg = args[i];

 						if (arg.startsWith(options.getNamePrefix())) { // Named parameters:

 							String paramName = arg.substring(options.getNamePrefix().length());

 							String paramValue = fetchNext(args, ++i);

 							options.addNamedParameter(new NamedParameter(paramName, paramValue, namedTypes.get(paramName)));

 						} else { // Numbered parameters:

 							Parameter parameter;

 							if (numberedTypes.isEmpty()) {

 								parameter = new Parameter(arg, null);

 							} else {

 								int paramIndex = options.getNumberedParameters().size();

 								int paramType;

 								try {

 									paramType = numberedTypes.get(paramIndex);

 								} catch (IndexOutOfBoundsException e) {

 									throw new IllegalArgumentException("Missing type for parameter #" + paramIndex, e);

 								} catch (NullPointerException e) {

 									throw new IllegalArgumentException("Invalid type definition for parameter #" + paramIndex, e);

 								}

 								parameter = new Parameter(arg, paramType);

 							}

 							options.addNumberedParameter(parameter);

 						}

 					}

 					break;

 				default:

 					throw new IllegalArgumentException("Unknown option: " + arg);

 			}

 		}

 		return options;

 	}

 	private String fetchNext(String[] args, int index) {

 		if (index < args.length) {

 			return args[index];

 		} else {

 			throw new IllegalArgumentException("Expecting value for option: " + args[index - 1]);

 		}

 	}

 	public static class Tokens {

 		public static final String DB = "--db";

 		public static final String SQL = "--sql";

 		public static final String SQL_UPDATE = "--sql-update";

 		public static final String SQL_INSERT = "--sql-insert";

 		public static final String BATCH = "--batch";

 		public static final String DATA = "--data";

 		public static final String NAME_PREFIX = "--name-prefix";

 		public static final String TYPES = "--types";

 		private Tokens() {

 		}

 	}

 	private int getType(String typeString) {

 		Integer type = types.get(typeString);

 		if (type == null) {

 			throw new IllegalArgumentException("Unsupported type: " + typeString);

 		} else {

 			return type;

 		}

 	}

 }